CN117485572A

CN117485572A - Controlling a hybrid electric or all-electric powertrain and propulsion system

Info

Publication number: CN117485572A
Application number: CN202310937965.2A
Authority: CN
Inventors: 格里高利·L·德特韦勒; 斯特凡诺·埃托雷; 托马斯·威廉·布朗
Original assignee: GE Avio SRL; General Electric Co
Current assignee: GE Avio SRL; General Electric Co
Priority date: 2022-07-29
Filing date: 2023-07-28
Publication date: 2024-02-02

Abstract

A hybrid electric or all-electric powertrain may include a power control unit electrically coupled to an energy storage system. The power control unit may determine the power level command based at least in part on the power level request of the powertrain and the power level UCL and/or the power level LCL. The power level UCL and/or the power level LCL may be based at least in part on an aggregate front power level request that represents a requested power level of one or more front face powertrains electrically coupled to the energy storage system. The power level command may be limited by the power level UCL and/or the power level LCL. The power level UCL may be set equal to the available discharge power capacity or the allocated discharge power capacity. The power level LCL may be set equal to the available storage power capacity or the allocated storage power capacity.

Description

Controlling a hybrid electric or all-electric powertrain and propulsion system

Priority information

The present application claims priority from italian patent application No. 102022000016215 filed on 7/29 of 2022.

Technical Field

The present disclosure relates generally to systems and methods for controlling hybrid electric or all-electric powertrains and propulsion systems of vehicles (e.g., aircraft).

Background

Aircraft and other vehicles may utilize hybrid or all-electric propulsion systems that include multiple hybrid or all-electric powertrains. Hybrid or all-electric propulsion systems may provide improved fuel efficiency and reduced emissions, as well as reduced operating costs. Accordingly, it would be welcomed in the art to provide improved hybrid electric and all-electric powertrain and propulsion systems, and improved systems and methods of controlling such powertrain and propulsion systems.

Drawings

A full and enabling disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

FIG. 1 shows a schematic cross-sectional view of an exemplary aircraft including a hybrid electric propulsion system;

FIG. 2A schematically depicts an exemplary hybrid electric propulsion system including a plurality of hybrid electric powertrains;

FIG. 2B schematically depicts another example hybrid electric powertrain;

FIG. 2C schematically depicts yet another exemplary hybrid electric powertrain;

FIG. 2D schematically depicts yet another exemplary hybrid electric powertrain;

FIG. 2E schematically depicts an exemplary all-electric powertrain;

3A-3D schematically depict exemplary operating conditions of an exemplary hybrid electric or all-electric propulsion system;

FIG. 4 schematically depicts features of an exemplary power control module for a hybrid electric or all-electric powertrain;

FIG. 5A schematically depicts an exemplary control limit module, which may be included in a power control module of a hybrid electric or all-electric powertrain, for example;

FIG. 5B schematically depicts another example control limit module that may be included in a power control module of a hybrid electric or all-electric powertrain, for example;

FIG. 6 schematically depicts an exemplary control command module that may be included in a power control module of a hybrid electric or all-electric powertrain, for example;

FIG. 7A shows a graph depicting an exemplary power discharge coefficient as a function of state of charge, for example, that may be utilized by the control limit module to determine the power level UCL;

FIG. 7B shows a graph depicting an exemplary charging coefficient as a function of state of charge, for example, that may be utilized by the control limit module to determine the power level LCL;

8A-8E illustrate a flowchart depicting an exemplary method of controlling a hybrid or all-electric propulsion system or powertrain; and

FIG. 9 schematically depicts an example control system that may be used to control a hybrid electric or all-electric propulsion system.

Detailed Description

Reference will now be made in detail to embodiments of the disclosure, one or more examples of which are illustrated in the drawings. The embodiments shown in the figures and described in the specification are provided by way of example and not to limit the disclosure.

The present disclosure uses numerical and letter designations to refer to features in the drawings. Like or similar reference numerals have been used in the drawings and description to refer to like or similar parts of the disclosure. Letter designations (e.g., "a," "b," etc.) following the numerical designation refer to sequential instances of elements identified by the numerical designation, respectively, and in other instances refer to the same or similar elements identified by the numerical designation without such letter designation.

The word "exemplary" is used herein to mean "serving as an example, instance, or illustration. Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. In addition, all embodiments described herein are to be considered exemplary unless explicitly stated otherwise.

The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

In the context of, for example, "at least one of A, B or C," the term "at least one" refers to a alone, B alone, C alone, or any combination of A, B and C.

As used herein, the terms "first," "second," and "third" may be used interchangeably to distinguish one component from another and are not intended to represent the location or importance of the respective components.

The term "nominal speed" as used herein with respect to a powertrain or propulsion system, or with respect to an internal combustion engine (e.g., a gas turbine engine), or with respect to an electric machine, refers to the maximum rotational speed that may be achieved during normal operation. For example, the rated speed may be achieved during maximum load operation, such as during take-off or climb operations.

The term "cruise speed" as used herein with respect to a powertrain or propulsion system, or with respect to an internal combustion engine (e.g., a gas turbine engine), or with respect to an electric machine, refers to its operation at a relatively high rotational speed for a period of time. For example, cruise speeds achieved at the aircraft level after climbing to a specified altitude. In some embodiments, the cruise speed may be 50% to 90% of the rated speed, for example 70% to 80% of the rated speed. In some embodiments, cruise speed may be achieved at 80% of full throttle, such as 50% to 90% of full throttle, such as 70% to 80% of full throttle.

The term "nominal operating speed" as used herein with respect to a powertrain or propulsion system, or with respect to an internal combustion engine (e.g., a gas turbine engine), or with respect to an electric machine, refers to operation at rotational speeds greater than idle and less than nominal speed. For example, the nominal operating speed may include an operating speed that is at least 10% greater than idle and at least 10% less than nominal. As an example, the nominal operating speed may include operating at a cruising speed.

The term "high power operating speed" as used herein with respect to a powertrain or propulsion system, or with respect to an internal combustion engine (e.g., a gas turbine engine), or with respect to an electric machine, refers to operating at a rotational speed of at least 90% of the rated speed of the engine.

The term "low power operating speed" as used herein with respect to a powertrain or propulsion system, or with respect to an internal combustion engine (e.g., a gas turbine engine), or with respect to an electric machine, refers to operating at idle speeds or speeds less than 10% greater than idle.

The terms "coupled," "fixed," "attached to," and the like, refer to a direct coupling, fixed or attachment, as well as an indirect coupling, fixed or attachment via one or more intermediate elements or features, unless otherwise specified herein.

The term "electrically coupled" as used herein with respect to a plurality of elements refers to elements configured to transmit electrical power therebetween through actuation of one or more intermediate elements or features, and/or including through an electrical switch or other power management element or feature.

The present disclosure generally provides hybrid electric and all-electric propulsion systems and powertrains, and systems and methods for controlling such propulsion systems and powertrains. The propulsion system of the present disclosure may include a plurality of powertrains each including one or more electric motors and a power control unit. The corresponding powertrain may include one or more electric machines that convert electric power into mechanical power, for example, to rotate one or more propellers. Additionally, or in the alternative, one or more electric machines may generate electric power that may be supplied to an energy storage system and/or to another powertrain included in the propulsion system. For a hybrid electric propulsion system or powertrain, the respective powertrain may include an internal combustion engine, such as a gas turbine engine. The internal combustion engine may generate mechanical power that may be used to rotate one or more propellers and/or generate electrical power via one or more electric machines. The respective power assemblies may be electrically coupled to each other and/or to the energy storage system, for example, via a power distribution bus. The respective powertrains may utilize the energy storage system as a shared resource, including as an electrical power supply, e.g., for rotating one or more propellers in the powertrain and/or for storing electrical power generated by the powertrain. Additionally, or in the alternative, the respective powertrains may each supply electrical power to another powertrain included in the propulsion system and/or may receive electrical power from such another powertrain.

One or more of the respective powertrains may include a power control unit that, for example, independently controls at least a portion of the operation of the respective powertrains, independent of the monitoring system and independent of communication between the respective power control units and/or the electronic controller. The power control unit of the corresponding powertrain may include an electronic controller and one or more power management devices that operate in accordance with control commands from the electronic controller. The power control unit may include one or more control modules configured to determine a power level command for the powertrain and provide the power level command to the power management device. One or more control modules may allow the power control unit and/or electronic controller to independently control various operations of the powertrain, including, for example, based on constraint limits of the overall propulsion system that may vary from time to time.

One or more control modules of the respective power control units may determine a power level command based at least in part on the power level request of the corresponding powertrain. The power level command may be limited by an upper power level control limit (power level UCL) and/or a lower power level control limit (power level LCL). The power level UCL and/or the power level LCL may be determined based on an aggregate front side power level request that represents a sum of one or more front side (flop) power level requests. The one or more front side power level requests each represent a power level request to another powertrain in the propulsion system. By limiting the power level commands of the respective powertrains by the power level UCL and/or the power level LCL determined based on the aggregate front power level request, the respective powertrains may be independently controlled according to the constraint limits of the overall propulsion system, independent of the monitoring system and independent of communication between the respective power control units and/or electronic controllers. For example, when the power level request of the powertrain is between the power level UCL and the power level LCL, a power level command corresponding to the power level request may be provided to the powertrain, e.g., to one or more power management devices. Additionally, or in the alternative, the power level command may be set to correspond to the power level UCL when the power level request of the powertrain is greater than the power level UCL determined based on the aggregate front power level request; and/or when the power level request of the powertrain is less than the power level LCL determined based on the aggregate front power level request, the power level command may be set to correspond to the power level LCL. In this way, the power level command of the corresponding powertrain may remain within the constraints of the overall propulsion system.

The power level UCL may be determined based at least in part on the greater of the available discharge power capacity and the allocated discharge power capacity. The available discharge power capacity may include or represent a difference resulting from subtracting (i) the aggregate front power level request from (ii) a power discharge threshold that includes or represents a threshold level for discharging from the energy storage system. The allocation of discharge power capacity may include or represent an allocation of a power discharge threshold to the powertrain. By determining the power level UCL based at least in part on the greater of the available discharge power capacity and the allocated discharge power capacity, it may be ensured that the powertrain is able to obtain its respective allocated power discharge threshold while also being able to obtain more than the allocated power discharge threshold when the aggregate front power level request is such that the available portion of the power discharge threshold is greater than the allocated discharge power capacity, e.g., because the aggregate front power level request is less than the allocation of power discharge thresholds to those front powertrains, and/or because one or more of the front powertrains are generating electrical power and/or supplying electrical power to the propulsion system.

The power level LCL may be determined based at least in part on the lesser of the available storage power capacity and the allocated storage power capacity. The available storage power capacity may include or represent a difference resulting from subtracting (i) the aggregate front power level request from (ii) a charging threshold that includes or represents a threshold level for supplying electrical power to the energy storage system. Allocating storage power capacity may include or represent allocation of a charging threshold to the powertrain. By determining the power level UCL based at least in part on the lesser of the available storage power capacity and the allocated discharge power capacity, it may be ensured that the powertrain is able to obtain its respective allocated charge threshold while also being able to obtain more charge threshold than allocated when the aggregate front power level request is such that the available portion of charge threshold is greater than the allocated storage power capacity, e.g., because the aggregate front power level request is less than the allocation of charge thresholds to those front powertrains, and/or because one or more of the front powertrains are consuming electrical power from the propulsion system.

In some embodiments, the powertrain may receive, at a given time, a corresponding allocated electrical power from the energy storage system that exceeds a power discharge threshold, for example, by utilizing an unused portion of the power discharge threshold that would otherwise be allocated to a front powertrain in the propulsion system. Additionally, or in the alternative, the powertrain may receive electrical power from the power distribution bus that exceeds a power discharge threshold of the energy storage system at a given time, for example, by utilizing electrical power supplied to the power distribution bus by one or more front side powertrains.

In some embodiments, the powertrain may provide the energy storage system with a corresponding allocation of electrical power exceeding a charge threshold at a given time, for example, by utilizing an unused portion of the charge threshold that would otherwise be allocated to a front powertrain in the propulsion system. Additionally, or in the alternative, in some embodiments, the powertrain may supply electrical power to the power distribution bus that exceeds a charge threshold of the energy storage system at a given time, for example, by providing electrical power to the power distribution bus that is available to one or more front side powertrains.

By determining the power level UCL and the power level LCL in accordance with the present disclosure, a power level request that is close to zero will inherently take precedence over a power level request that is close to and/or exceeds the corresponding power level UCL or power level LCL. In this way, the power level commands to the respective powertrains inherently balance, at least in part, the load between the respective powertrains. For example, by determining the power level UCL of the respective powertrain based on the greater of the available discharge power capacity and the allocated discharge power capacity, a powertrain having a power level request closer to zero will receive a corresponding power level command having an inherent priority that is higher than the front power level request of a front powertrain that approaches or exceeds the power level UCL. Additionally, or in the alternative, by determining the power level LCL of the respective powertrain based on the lesser of the available storage power capacity and the allocated storage power capacity, a powertrain having a power level request closer to zero will receive a corresponding power level command having an inherent priority that is higher than the front power level request of a front powertrain that is closer to or exceeds the power level LCL.

The present disclosure may provide more efficient energy utilization in a hybrid or all-electric propulsion system, including, for example, more efficient allocation of power discharge capacity and/or charge capacity in a corresponding powertrain in the propulsion system. More efficient energy utilization may be translated into improved operating range and/or fuel efficiency of an aircraft or other vehicle powered by the propulsion system. Additionally, or in the alternative, the present disclosure may provide improvements in a lower emissions and/or lower operating costs.

The present disclosure may provide improved scalability for hybrid electric or all-electric propulsion systems that include a large number of powertrains. For example, the presently disclosed system and method of controlling a propulsion system or powertrain may be used to control a corresponding powertrain in a propulsion system that includes any desired number of front face powertrains. Additionally, or in the alternative, the front side powertrains may be added or subtracted, and/or transitioned from online to offline (e.g., from an operating state to a non-operating state), without the need to change the presently disclosed systems and methods to accommodate different numbers of front side powertrains.

Exemplary embodiments of the present disclosure will now be described in more detail. Referring to fig. 1, embodiments of the presently disclosed hybrid electric propulsion system may be incorporated into any desired vehicle, such as an aircraft 100. Additionally, or alternatively, the system and/or method of controlling a hybrid electric propulsion system may be incorporated into any such desired vehicle, including aircraft 100. The aircraft 100 depicted in fig. 1 may be any type of aircraft including a multiple engine hybrid electric propulsion system, including any fixed wing aircraft, such as a turbojet or turboprop, or any rotorcraft including a multiple engine hybrid electric propulsion system, such as a helicopter. For example, the aircraft 100 may be a multi-engine Liu Deji aircraft, a multi-engine offshore class aircraft, or the like.

As shown, the aircraft 100 includes a hybrid electric propulsion system 200. The hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202. The exemplary hybrid electric propulsion system 200 may include any number of hybrid electric powertrains 202. In the embodiment shown in FIG. 1, the hybrid electric propulsion system 200 includes two hybrid electric powertrains 202. In further embodiments, the hybrid electric propulsion system 200 may include n hybrid electric powertrains 202. For example, the hybrid electric propulsion system 200 may include n hybrid electric powertrains 202, where the number n is 2 to 20, such as 2 to 6, such as 6 to 12, or such as 12 to 18. Respective ones of the plurality of hybrid electric powertrains 202 may include an internal combustion engine 204 and an electric machine 206. As shown in FIG. 1, a respective hybrid electric powertrain of the plurality of hybrid electric powertrains 202 may have a wing-mounted configuration. Additionally, or in the alternative, one or more hybrid electric powertrains 202 may be mounted at any other suitable location on the aircraft 100.

The internal combustion engine 204 may be a gas turbine engine, such as a turbojet engine, a turbofan engine, a turboprop engine, a propeller fan engine, or a turboshaft engine. In some embodiments, the internal combustion engine 204 may be a counter-flow turboprop gas turbine engine. For example, the aircraft 100 may be a fixed-wing aircraft including a plurality of hybrid electric powertrains 202, the plurality of hybrid electric powertrains 202 each including an internal combustion engine 204 configured as a counter-flow turboprop gas turbine engine. In some embodiments, the internal combustion engine 204 may be a turboshaft gas turbine engine. For example, the aircraft 100 may be a rotorcraft including a plurality of hybrid electric powertrains 202, the plurality of hybrid electric powertrains 202 each including an internal combustion engine 204 configured as a turboshaft gas turbine engine. The electric machine 206 may be or include an electric motor and/or a generator. The internal combustion engine 204 and the motor 206 may provide torque to one or more propellers 208. One or more propellers 208 may be rotated under torque provided by the internal combustion engine 204 and/or the electric motor 206, providing propulsion thrust to power the aircraft 100.

The motor 206 may include any suitable induction motor, reluctance motor, and/or Permanent Magnet (PM) motor. In some embodiments, the hybrid electric powertrain 202 may include an electric machine 206 configured as a motor/generator. Additionally, or in the alternative, the hybrid electric powertrain 202 may include a plurality of electric machines 206, such as a first electric machine 206 configured as an electric motor and a second electric machine 206 configured as a generator. For example, the exemplary motor 206 may be or include an Induction Motor (IM), a Switched Reluctance Motor (SRM), a Wound Rotor Synchronous Motor (WRSM), a Permanent Magnet Synchronous Motor (PMSM), a slotless PMSM, a PM assisted synchronous reluctance motor (PM assisted SynRM), a brushless DC (BLDC) motor, a Brushless Doubly Fed Reluctance Motor (BDFRM), and the like.

The exemplary hybrid electric powertrain 202 may provide a total propulsion power of from 0.5 Megawatts (MW) to 60MW, such as from 0.5MW to 3.0MW, such as from 2.0MW to 5.0MW, such as from 5.0MW to 25.0MW, such as from 25MW to 60MW. The total propulsion power output of the hybrid electric powertrain 202 may be distributed between the internal combustion engines 204 in the electric machines 206 in any desired proportion ranging from 0% to 100%, including, for example, during different operating periods, such as during different phases of flight, in different proportions. The exemplary motor 206 included in the hybrid electric powertrain 202 may provide an electrical power output of from 50 kilowatts (kW) to 30MW, such as from 50kW to 500kW, such as from 500kW to 1MW, such as from 1MW to 5MW, such as from 5MW to 12MW, such as from 12MW to 20MW, or such as from 20MW to 30MW.

As shown in fig. 1, one or more of the impellers 208 may be or include an impeller assembly. Additionally, or in the alternative, one or more of the impellers 208 may comprise ducted or ductless fan assemblies. For example, the gas turbine engine may be a propeller fan (sometimes referred to as an open rotor engine or an ultra-high bypass turbofan) that may include one or more propellers 208 configured as ductless fan assemblies. As another example, a gas turbine engine configured as a turbofan may include one or more propellers 208 configured as a ducted fan assembly.

The hybrid electric propulsion system 200 may include an energy storage system 210. The energy storage system may be a shared resource of multiple hybrid electric powertrains 202. The energy storage system 210 may include one or more energy storage units, such as one or more batteries, and the like. The energy storage system 210 may supply electrical power to and/or receive and store electrical power from respective ones of the plurality of hybrid electric powertrains 202. In some embodiments, the hybrid electric propulsion system 200 may include a power distribution bus 212, the power distribution bus 212 being configured to supply power to and/or receive and store power from respective ones of the plurality of hybrid electric powertrains 202. The power distribution bus 212 may distribute power at a suitable voltage for operation of the hybrid electric powertrain 202 and the energy storage system 210. The power distribution bus 212 may distribute power in the form of Direct Current (DC) using any suitable power distribution scheme, including, for example, one or more power distribution loops, branches, pass filters, relays, switches, converters (e.g., DC/DC converters), devices operable to control the flow of current, and the like.

The energy storage system 210 may include any one or more devices configured for energy storage and/or generation. For example, energy storage system 210 may include an electrochemical energy storage system, an electrical energy storage system, and/or a mechanical energy storage system. Additionally, or in the alternative, the energy storage system 210 may include an electrochemical power generation system, such as a fuel cell or other suitable electrochemical cell, and/or a photovoltaic power generation system, such as a solar cell array. Exemplary electrochemical energy storage systems include batteries, such as lithium ion batteries, nickel metal hydride batteries, lead acid batteries, nickel zinc batteries, nickel cadmium batteries, and the like. Exemplary electrical energy storage systems include capacitors, supercapacitors (e.g., electrostatic double layer capacitors, electrochemical pseudocapacitors, hybrid capacitors, etc.), and the like. Exemplary mechanical energy storage systems include flywheel energy storage systems, compressed air energy storage systems, regenerative braking systems, and the like. Exemplary fuel cells include solid oxide fuel cells, molten carbonate fuel cells, proton exchange membrane fuel cells, solid acid fuel cells, alkaline fuel cells, phosphoric acid fuel cells, hydrogen oxygen fuel cells, and the like. In some embodiments, an electrochemical power generation system (e.g., a fuel cell) may be combined with an electrochemical or electrical energy storage system. For example, the fuel cell may charge an electrochemical or electrical energy storage system and/or provide electrical power to the plurality of hybrid electric powertrain 202. Additionally, or in the alternative, such electrochemical or electrical energy storage systems may receive and store electrical energy provided by a plurality of hybrid electric powertrains 202.

Respective ones of the plurality of hybrid electric powertrains 202 may include a power control unit 214. The hybrid electric propulsion system 200 may include a plurality of power control units 214 electrically coupled to the power distribution bus 212. The respective power control unit 214 may include one or more power management devices 216 and an electronic controller 218. The one or more power management devices may include one or more inverters, converters, rectifiers, devices operable to control current flow, and the like. For example, one or more power management devices may be used to regulate and/or convert electrical power (e.g., from AC to DC or vice versa). In some embodiments, one or more power management devices 216 may include one or more inverters. The one or more inverters may convert DC power provided by the power distribution bus 212 to AC power for use by the respective hybrid electric powertrain 202 and/or motor 206. Additionally, or in the alternative, one or more power management devices 216 may include one or more rectifiers. One or more inverters may convert AC power generated by the respective hybrid electric powertrain 202 and/or motor 206 to DC power distributed over the power distribution bus 212. AC power used by the respective hybrid electric powertrain 202 and/or electric machine 206.

In some embodiments, one or more power management devices 216 may be bi-directional. For example, the one or more power management devices 216 may include a synchronous converter, such as a synchronous buck converter. As another example, the one or more power management devices 216 may include a bi-directional interleaved converter. In yet another embodiment, the one or more power management devices 216 may include one or more autotransformer rectifier units, for example, to convert AC power to DC power. Additionally, or in the alternative, the one or more power management devices 216 may include one or more matrix converters, such as one or more indirect matrix converters and/or one or more direct matrix converters. One or more matrix converters may have inherent bi-directional power flow capability.

The one or more power management devices 216, such as one or more inverters, converters, and/or rectifiers, may include semiconductors suitable for high frequency, high voltage, high temperature, high power density, and high efficiency applications, such as silicon carbide and/or gallium nitride. For example, the one or more power management devices 216 may be Metal Oxide Semiconductor Field Effect Transistors (MOSFETs), metal semiconductor field effect transistors (MESFETs), insulated Gate Bipolar Transistors (IGBTs), high Electron Mobility Transistors (HEMTs), or the like. Exemplary power management device 216 may have a nominal efficiency of at least 98%, such as at least 99%. Additionally, or in the alternative, the exemplary power management device 216 may have a power density of from 1kW/kg to 30kW/kg, such as from 5kW/kg to 15kW/kg, such as from 15kW/kg to 20kW/kg, or such as from 20kW/kg to 300kW/kg. Additionally, or in the alternative, exemplary power management device 216 may have a power delivery capability of from 200kW to 3MW, such as from 500kW to 2MW, or such as from 1MW to 3MW. In some embodiments, the power control unit 214 may include a cooling system, such as a cryogenically cooled system.

The electronic controller 218 of the respective power control unit 214 may be incorporated into the power control unit 214 or in conjunction with the power control unit 214, or the electronic controller 218 may be provided as a separate component communicatively coupled to the power control unit 214. In some embodiments, the electronic controller 218 and the one or more power management devices 216 may be provided as a common unit configured to perform one or more operations of the power control unit 214. Additionally, or in the alternative, one or more power management devices 216 may be entirely contained within power control unit 214, or one or more of power management devices 216 may be located separately from power control unit 214, but electrically and/or communicatively coupled with power control unit 214.

The electronic controller 218 may be configured as or incorporated into an Engine Control Unit (ECU), an Electronic Engine Controller (EEC), an all digital engine control (FADEC) system, or the like. The respective power control units 214 and/or electronic controllers 218 thereof may be configured as distributed control systems, such as distributed control systems dedicated to the respective hybrid electric powertrain 202. The respective power control units 214 and/or their electronic controllers 218 may operate independently of each other, e.g., without a supervisory control system and without providing communication between the respective power control units 214 and/or electronic controllers 218. The respective power control unit 214 and/or electronic controller 218 thereof may control at least a portion of the hybrid electric powertrain 202, such as the electric machine 206, the internal combustion engine 204, and/or the one or more propellers 208. Additionally, or in the alternative, the respective power control unit 214 and/or its electronic controller 218 may control one or more power management devices 216. For example, the power control unit 214 may be operable to control electrical power provided by the electric machine 206 and/or the energy storage system 210, such as electrical power from the electric machine 206 and/or the energy storage system 210 to the propeller 208 and/or electrical power provided by the electric machine 206 to the energy storage system 210.

In some embodiments, the electronic controller 218 may control various further operations of the hybrid electric powertrain 202 (e.g., in addition to operation of the electric machine 206 and/or the one or more power management devices 216), such as operation of the internal combustion engine 204 and/or operation of the propeller 208. The electronic controller 218 may control a torque output of the hybrid electric powertrain 202 (e.g., a torque output of the internal combustion engine 204 and/or the electric machine 206), such as a torque output to the propeller 208, for example, by controlling a fuel flow to the internal combustion engine 204 and/or a power output of the electric machine 206. Additionally, or in the alternative, the electronic controller 218 may control the speed and/or thrust of the propeller 208, for example, by controlling the fuel flow to the internal combustion engine 204 and/or the power output of the electric motor 206.

The hybrid electric propulsion system 200 may include one or more input devices 220. The respective power control unit 214 may receive control inputs from the respective input device 220. The input device 220 may include any suitable device for providing control input to the respective power control unit 214, including manual and/or automatic devices. For example, the input device 220 may include one or more thrust levers, power levers, and the like. Additionally, or in the alternative, the input device 220 may include an automatic throttle system, such as an automatic throttle, an automatic thrust, or the like. One or more input devices 220 may be actuated by the pilot, co-pilot, and/or autopilot system to provide power input commands to respective ones of the plurality of hybrid electric powertrains 202. The one or more input devices 220 may be located in the cockpit of the aircraft 100 or elsewhere on the aircraft 100. In some embodiments, one or more input devices 220, such as an automatic throttle system, may be actuated by the pilot, co-pilot, and/or autopilot system to provide power input commands to respective ones of the plurality of hybrid electric powertrains 202 by specifying desired flight characteristics, e.g., in addition to or as an alternative to manually providing power input commands. In some embodiments, the automatic throttle system may include a speed mode and/or a thrust mode. In speed mode, the automatic throttle system may provide a power input command configured to achieve a specified target speed, such as a specified target airspeed. The corresponding power control unit 214 may maintain an appropriate stall margin and/or an appropriate overspeed margin. For example, if the specified target speed is slower than the stall speed, or faster than the maximum speed, the automatic throttle system may provide a power input command configured to maintain the speed near the specified target speed within a range that includes an appropriate stall margin and/or an appropriate overspeed margin. In the thrust mode, the automatic throttle system may provide a power input command configured to maintain a thrust level corresponding to the respective flight phase. Exemplary phases of flight may include idling, takeoff, climbing, cruising, descent, landing, taxiing, and the like. The automatic throttle system may provide a power input command configured to maintain a constant thrust during a respective flight phase, for example, until a transition to the flight phase. For example, during takeoff, the automatic throttle system may provide a power input command corresponding to a takeoff power level, e.g., until the takeoff phase transitions to the climb phase. During the climb phase, the automatic throttle system may provide power input commands corresponding to the climb power level, e.g., until the climb phase transitions to the cruise phase, and so on. The transition to the respective flight phase may be actuated manually and/or automatically by the pilot, co-pilot and/or autopilot system, as the case may be.

Referring now to fig. 2A-2D, an exemplary hybrid electric propulsion system 200 is further described. In some embodiments, the hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202 configured as shown in fig. 2. Additionally, or in the alternative, the hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202 configured as shown in fig. 2B, 2C and/or 2D. Additionally, or in the alternative, in some embodiments, the presently disclosed subject matter may be implemented in an all-electric propulsion system. For example, fig. 2E illustrates an exemplary all-electric propulsion system and/or powertrain.

The hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202, such as (n) hybrid electric powertrains 202. For example, fig. 2A shows a hybrid electric propulsion system 200 that includes a first hybrid electric powertrain 202A and a second hybrid electric powertrain 202b. The corresponding hybrid electric powertrain 202 may be configured as described with reference to fig. 1 and/or as further described herein.

The respective hybrid electric powertrain 202 may be electrically coupled to a power distribution bus 212. One or more energy storage systems 210 may be electrically coupled to a power distribution bus 212. The one or more energy storage systems 210 may be shared resources for a plurality of hybrid electric powertrains 202. The one or more energy storage systems 210 may provide electrical power to at least some of the plurality of hybrid electric powertrains 202. Additionally, or in the alternative, a respective hybrid electric powertrain of the plurality of hybrid electric powertrains 202 may receive electrical power from the at least one energy storage system 210 and/or provide electrical power to the at least one energy storage system 210 (e.g., the energy storage system 210 configured as a shared resource of at least some of the plurality of hybrid electric powertrains 202).

The respective hybrid electric powertrain of the plurality of hybrid electric powertrains 202 can have any desired powertrain configuration. For example, exemplary powertrain configurations for the hybrid electric powertrain 202 include series, parallel, or series-parallel. In general, the term "series" or "series configuration," when used with reference to a hybrid electric powertrain 202, refers to a hybrid electric powertrain 202 having one mechanical power source configured to drive a propeller 208. The mechanical power source for the series configuration may be an internal combustion engine 204 or an electric motor 206. In general, the term "parallel" or "parallel configuration," when used in reference to a configuration of the hybrid electric powertrain 202, refers to the hybrid electric powertrain 202 configured such that both the internal combustion engine 204 and the electric machine 206 may simultaneously or individually provide mechanical power to the propeller 208 at a given time. In general, the term "series-parallel" or "series-parallel configuration," when used with reference to a configuration of the hybrid electric powertrain 202, refers to a hybrid electric powertrain 202 that includes both a series configuration and a parallel configuration incorporated into the hybrid electric powertrain 202.

The series-parallel configuration may sometimes be referred to as a "power split configuration" because the series-parallel configuration typically includes one or more transmission assemblies configured to allow input power and/or output power to be split among multiple resources. Depending on the power split provided by one or more transmission components, the hybrid electric powertrain 202 may operate in a series configuration or a parallel configuration at a given time. With the power split configuration including input split, the hybrid electric powertrain 202 may provide mechanical power to the propeller 208 from both the internal combustion engine 204 and the electric machine 206 at a given time, either simultaneously or separately. With a power distribution configuration including output distribution, the hybrid electric powertrain 202 may distribute mechanical power input to the transmission components between the propeller 208 and the electric power generated by the electric machine 206 at a given time, either simultaneously or separately. The hybrid electric powertrain 202, which includes both input split and output split, is sometimes referred to as a "compound split" or "compound power split configuration.

Regardless of the particular powertrain configuration, the hybrid electric powertrain 202 may utilize an internal combustion engine 204, such as a gas turbine engine, to generate power for propulsion provided by one or more propellers 208 and/or to power an electric motor 206, which electric motor 206 in turn generates power for propulsion provided by one or more propellers 208. The motor 206 may be provided as a single unit or as multiple units. For example, the first electric machine 206 may be or include a generator and the second electric machine 206 may be or include an electric motor. Additionally, or in the alternative, the hybrid electric powertrain 202 may include a plurality of electric machines 206, such as a plurality of generators and/or a plurality of motors. The electrical power generated by the motor 206 may be converted into mechanical power for rotating the one or more propellers 208. Additionally, or in the alternative, electrical power generated by the electric machine 206 may be provided to the energy storage system 210. Additionally, or in the alternative, the energy storage system 210 may supply electrical power to the electric machine 206, and the electric machine 206 may convert the electrical power into mechanical power for rotating the one or more propellers 208. The distribution and use of power by the plurality of hybrid electric powertrains 202 may depend, at least in part, on one or more operating conditions of the hybrid electric propulsion system 200 and/or the respective hybrid electric powertrains 202, and/or on a flight phase of the aircraft 100 powered by the hybrid electric propulsion system 200.

The series configuration may include an electric motor 206 drivingly coupled to one or more propellers 208, and an internal combustion engine 204 drivingly coupled to the electric motor 206. The internal combustion engine 204 may drive the motor 206, generating electrical power, and the electrical power generated by the motor 206 may be used to drive one or more propellers 208. For example, the electric machine 206 may include an electric generator configured to generate electric power and/or one or more electric motors configured to drive one or more propellers 208. Additionally, or in the alternative, electrical power generated by the electric machine 206 may be provided to the energy storage system 210. In some embodiments, the series configuration may include a distributed electric powertrain. The distributed electromotive assembly may include an electric machine 206 configured as a generator powered by the internal combustion engine 204, and a plurality of electric machines 206 configured as electric motors that receive electric power from the generator and drive respective propellers 208.

The parallel configuration may include an internal combustion engine 204 and an electric motor 206 that are respectively drivingly coupled to one or more propellers 208. One or more of the propellers 208 may be powered at a given time by the internal combustion engine 204, the motor 206, or both the internal combustion engine 204 and the motor 206. One or more of the propellers 208 may be powered simultaneously and/or separately by the internal combustion engine 204 and/or the electric motor 206 at a given time. Additionally, or in the alternative, the internal combustion engine 204 may drive one or more propellers 208 and/or the motor 206, for example, simultaneously and/or separately. The parallel configuration may include a single axis configuration or a dual axis configuration. The single-shaft configuration may include a drive shaft drivingly coupled to the internal combustion engine 204 and the motor 206, the motor 206 drivingly coupled to the propeller 208, and a transmission disposed between the internal combustion engine 204 and the motor 206. The dual shaft configuration may include a first drive shaft drivingly coupled to the internal combustion engine 204 and a second drive shaft drivingly coupled to the motor 206. The dual shaft arrangement includes a transmission configured to transfer power from the first drive shaft and/or the second drive shaft to the propeller 208.

Referring now to FIG. 2A, a hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202 configured as shown. In some embodiments, the hybrid electric powertrain 202 shown in fig. 2A may represent a parallel configuration. Additionally, or in the alternative, the hybrid electric powertrain 202 shown in fig. 2A may represent a power split configuration. As shown, the hybrid electric powertrain 202 may include an internal combustion engine 204 and an electric machine 206 mechanically coupled to a transmission assembly 222, respectively.

The internal combustion engine 204 may be mechanically coupled to the transmission assembly 222 by an engine shaft 224. The motor 206 may be mechanically coupled to the drive assembly 222 via a mechanical shaft 226. The transmission assembly 222 may transfer mechanical power from the internal combustion engine 204 and/or the electric machine 206 to the one or more propellers 208. The propeller 208 may be mechanically coupled to the transmission assembly 222 by a propeller shaft 228. The transmission assembly 222 may include a gear arrangement adapted to provide a desired rotational speed of the propeller 208. Additionally, or in the alternative, the hybrid electric powertrain 202 may include a propeller gearbox 230 configured to provide a desired rotational speed of the propeller 208. For example, a propeller gearbox 230 may be disposed between the transmission assembly and the propeller 208.

The internal combustion engine 204 may be a turbine engine. For example, the internal combustion engine 204 may include one or more compressor sections 232, a combustion section 234, and one or more turbine sections 236 in serial flow relationship. One or more compressor sections 232 may draw in and compress air supplied to a combustion section 234. The pressurized air may be mixed with fuel in the combustion section 234 and the air and fuel mixture may be combusted, producing combustion products that flow into one or more turbine sections 236. The flow of combustion products through the one or more turbine sections 236 may generate torque that rotates one or more spools of the turbine engine. The one or more compressor sections 232 may be coupled to one or more spools of the turbine engine such that the one or more turbine sections 236 may rotate the one or more compressor sections 232 by rotation of the combustion products flowing therethrough to compress air flowing therethrough. The mechanical energy from the rotation of the one or more turbine sections 236 may be used to power the one or more propellers 208 and/or to generate electrical power by an electric motor 206 (e.g., by a transmission assembly 222) mechanically coupled to the internal combustion engine 204.

The hybrid electric powertrain 202 may include one or more electric machines 206. In some embodiments, as shown in FIG. 2A, the hybrid electric powertrain 202 may include an electric machine 206 configured as a motor/generator. Additionally, or in the alternative, the hybrid electric powertrain 202 having a parallel configuration may include a first electric machine 206 configured as an electric motor and a second electric machine 206 configured as a generator. The electric machine 206, configured as a motor/generator or as a motor, may receive electric power from the energy storage system 210. Additionally, or in the alternative, the electric motor 206 configured as a motor/generator or as a generator may generate electric power, for example, under mechanical power provided by the internal combustion engine 204 and/or the propeller 208 (e.g., through the transmission assembly 222). The electrical power generated by the motor 206 may be converted to mechanical power to power the propeller 208. Additionally, or in the alternative, electrical power generated by the electric machine 206 may be provided to the energy storage system 210.

As shown in fig. 2A, the supply of electrical power for and/or from the hybrid electric powertrain 202 will be controlled by a power control unit 214 electrically coupled to the power distribution bus 212. The power control unit 214 may control the supply of electrical power from the power distribution bus 212 and/or the energy storage system 210 to the electric machine 206 included in the hybrid electric powertrain 202, such as from the power distribution bus 212 and/or the energy storage system 210 to the electric machine 206 configured as an electric motor or as an electric motor/generator. Additionally, or in the alternative, the power control unit 214 may control the supply of electrical power from the electric machine 206 to the power distribution bus 212 and/or the energy storage system 210, such as the supply of electrical power from the electric machine 206 to the electric machine 06 configured as a generator or as a motor/generator. The power control unit 214 may include one or more power management devices 216, and an electronic controller 218, which electronic controller 218 is provided as an integrated component of the power control unit 214 or as a separate unit communicatively coupled to the one or more power management devices 216.

The hybrid electric powertrain 202 may include a fuel supply system 238 configured to supply fuel to the internal combustion engine 204. The fuel supply system 238 may include one or more fuel valves, distribution headers, fuel nozzles, and the like. The fuel supply system 238 may be controlled by the electronic controller 218.

As shown in fig. 2A, the hybrid electric propulsion system 200 includes an input device 220, the input device 220 configured to provide a power level request to a respective one of the power control units 214 associated with the corresponding hybrid electric powertrain 202. For example, the first hybrid electric powertrain 202a may include a first power control unit 214a and the second hybrid electric powertrain 202b may include a second power control unit 214. The first power control unit 214a may include a first one or more power management devices 216a and a first electronic controller 218a. The first electronic controller 218a may receive a power level request from the input device 220. The first electronic controller 218a may provide power level commands to the first one or more power management devices 216 a. The first one or more power management devices 216a may control the supply of electrical power to the first hybrid electric powertrain 202a and/or from the first hybrid electric powertrain 202a based at least in part on a power level command from the first electronic controller 218a.

The second power control unit 214b may include a second one or more power management devices 216b and a second electronic controller 218b. The second electronic controller 218b may receive a power level request from the input device 220. The second electronic controller 218b may provide power level commands to the second one or more power management devices 216 b. The second one or more power management devices 216b may control the supply of electrical power to the second hybrid electric powertrain 202b and/or from the second hybrid electric powertrain 202b based at least in part on power level commands from the second electronic controller 218b.

Referring now to FIG. 2B, another exemplary hybrid electric propulsion system is shown. In some embodiments, the hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202 configured as shown in fig. 2B. In some embodiments, the hybrid electric powertrain 202 shown in fig. 2B may represent a series configuration. Additionally, or in the alternative, the hybrid electric powertrain 202 shown in fig. 2B may represent a power split configuration. As shown, the hybrid electric powertrain 202 may include an internal combustion engine 204 (e.g., configured as a gas turbine engine) and an electric machine 206 configured in series, the internal combustion engine 204 mechanically coupled to the electric machine 206 via a transmission assembly 222, the electric machine 206 mechanically coupled to one or more propellers 208. Additionally, or in the alternative, the hybrid electric powertrain 202 may include an electric motor 206 and an internal combustion engine 204 configured in series, the electric motor 206 being mechanically coupled to the internal combustion engine 204 by a transmission assembly 222, and the internal combustion engine 204 being mechanically coupled to one or more propellers 208. The internal combustion engine 204 may be mechanically coupled to the transmission assembly 222 by an engine shaft 224. The drive assembly 222 may be mechanically coupled to the motor 206 by a machine shaft 226. The one or more propellers 208 may be mechanically coupled to the hybrid electric powertrain 202 (e.g., to the electric machine 206 or the internal combustion engine 204) by a propeller shaft 228.

The hybrid electric powertrain 202 having a series configuration may include one or more electric machines 206. For example, as shown in FIG. 2B, the electric machine 206 may be or include a motor/generator. Additionally, or in the alternative, the hybrid electric powertrain 202 having a series configuration may include a first electric machine 206 configured as an electric motor and a second electric machine 206 configured as a generator. The electric machine 206, configured as a motor/generator or motor, may receive electrical power from the energy storage system 210. Additionally, or in the alternative, the electric machine 206, configured as a motor/generator or generator, may generate electric power, for example, under mechanical power provided by the internal combustion engine 204 and/or the propeller 208 (e.g., through the transmission assembly 222). The electrical power generated by the motor 206 may be converted to mechanical power to power the propeller 208. Additionally, or in the alternative, electrical power generated by the electric machine 206 may be provided to the energy storage system 210.

Referring now to FIG. 2C, another exemplary hybrid electric propulsion system is shown. In some embodiments, the hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202 configured as shown in fig. 2C. In some embodiments, the hybrid electric powertrain 202 shown in fig. 2C may represent a series-parallel configuration. Additionally, or in the alternative, the hybrid electric powertrain 202 shown in fig. 2C may represent a power split configuration. As shown, in a series-parallel configuration, the hybrid electric powertrain 202 may include an internal combustion engine 204 (e.g., configured as a gas turbine engine) mechanically coupled to a transmission assembly 222, for example, via an engine shaft 224, and one or more electric machines 206 mechanically coupled to the transmission assembly 222, for example, via a corresponding one or more machine shafts 226. In some embodiments, the hybrid electric powertrain 202 having a series-parallel configuration may include a generator 240 and an electric motor 242. The generator 240 and the motor 242 may be provided as separate motors 206 or as a combined motor 206. The generator 240 may be mechanically coupled to the transmission assembly 222 by a generator shaft 244. The motor 242 may be mechanically coupled to the transmission assembly 222 by a motor shaft 246. The one or more propellers 208 may be mechanically coupled to the hybrid electric powertrain 202, such as to the transmission component 222, by a propeller shaft 228.

As shown in FIG. 2C, the internal combustion engine 204 may provide mechanical power to one or more propellers 208 and/or a generator 240 via a transmission assembly 222. Mechanical power from the internal combustion engine 204 may be provided to one or more of the propellers 208 and the generator 240 at a given time, either simultaneously or separately. The generator 240 may generate electrical power from mechanical power provided from, for example, the internal combustion engine 204 and/or the transmission assembly 222. The electrical power generated by generator 240 is supplied to power distribution bus 212 and/or energy storage system 210, for example, in accordance with a power level command from power control unit 214. Additionally, or in the alternative, electrical power generated by generator 240 may be provided to motor 242.

One or more of the propellers 208 may receive mechanical power from the internal combustion engine 204 and/or from the electric motor 242, for example, via a transmission assembly 222. At a given time, mechanical power may be provided to one or more of the propellers 208 by the internal combustion engine 204 and the electric motor 242, either simultaneously or separately. The motor 242 may convert electrical power into mechanical power. The electrical power may be provided by the energy storage system 210 and/or the power distribution bus 212, for example, in accordance with power level commands from the power control unit 214. Additionally, or in the alternative, mechanical power generated by the motor 242 may be provided to the generator 240.

Referring now to FIG. 2D, another exemplary hybrid electric propulsion system is shown. In some embodiments, the hybrid electric propulsion system 200 may include a plurality of hybrid electric powertrains 202 configured as shown in fig. 2D. In some embodiments, the hybrid electric powertrain 202 shown in fig. 2D may represent a series configuration including a distributed propulsion configuration. Additionally, or in the alternative, the hybrid electric powertrain 202 shown in fig. 2C may represent a power split configuration. As shown, in a series and/or distributed propulsion configuration, the hybrid electric powertrain 202 may include an internal combustion engine 204 (e.g., configured as a gas turbine engine) mechanically coupled to an electric machine 206 (e.g., configured as a generator or motor/generator). The internal combustion engine 204 may be mechanically coupled to the electric machine 206 by an engine shaft 224 and/or a machine shaft 226. The hybrid electric powertrain 202 shown in fig. 2D may include a transmission assembly 222 (not shown, see, e.g., fig. 2B) disposed between the internal combustion engine 204 and the electric machine 206.

As shown in fig. 2D, the hybrid electric powertrain 202 may distribute electric power generated by the electric machine 206 to a distributed propulsion system 248 including a plurality of propellers 208, e.g., according to a power level command from the power control unit 214. Additionally, or in the alternative, electrical power generated by the electric machine 206 may be supplied to the power distribution bus 212 and/or the energy storage system 210, for example, in accordance with a power level command from the power control unit 214. At a given time, electrical power may be supplied to the distributed propulsion system 248, and/or to the power distribution bus 212 and/or the energy storage system 210, either simultaneously or separately. At a given time, electrical power may be supplied to the distributed propulsion system 248 from the electric machine 206 and/or the power distribution bus 212 and/or the energy storage system 210 simultaneously or individually. Electrical power may be supplied to the distributed propulsion system 248 in accordance with power level commands from the power control unit 214.

The distributed propulsion system 248 may include a plurality of propeller power units 250. Respective ones of the plurality of propeller power units 250 may include the motor 206, the power control unit 214, and the propeller 208. The motor 206 included as part of the propeller power unit 250 may sometimes be referred to as a propeller machine 252. The power control unit 214 that is part of the propeller power unit 250 may sometimes be referred to as a propeller power control unit 254. The propeller machine 252 may be mechanically coupled to the propeller 208, for example, by a propeller shaft 228. The propeller power unit 250 may include a propeller gearbox 230 configured to provide a desired rotational speed of the propeller 208. For example, a propeller gearbox 230 may be disposed between the propeller machine 252 and the propeller 208.

The respective propeller power control units 254 may be electrically coupled to a propeller power distribution bus 256, which propeller power distribution bus 256 is configured to supply power to and/or receive power from respective ones of the plurality of propeller power units 250. The electrical power may be supplied to the propeller power distribution bus 256 by the power control unit 214. The propeller power distribution bus 256 may receive electrical power from the electric machine 206 and/or the energy storage system 210 and/or the power distribution bus 212, for example, according to power level commands from the power control unit 214.

The respective propeller power control unit 254 may include one or more power management devices 216 and an electronic controller 218, each configured substantially as described herein with respect to the power control unit 214. The one or more power management devices 216 that are part of the propeller power control unit 254 may sometimes be referred to as propeller power management devices. The electronic controller 218 that is part of the propeller power control unit 254 may sometimes be referred to as a propeller electronic controller. For example, the respective propeller power units 250 may receive electrical power from the propeller power distribution bus 256 in accordance with a power level command from the propeller electronic controller of the propeller power control unit 254. The respective propeller machines 252 may convert electrical power into mechanical power for rotating the respective propellers 208. Additionally, or in the alternative, the respective propeller machines 252 may generate electrical power from mechanical input from rotation of the respective propellers 208. The propeller power control units 254 corresponding to the respective propeller machines 252 may supply the electrical power generated by the propeller machines 252 to a propeller power distribution bus 256.

Referring now to FIG. 2E, an exemplary all-electric powertrain 260 is shown. The all-electric powertrain 260 shown in fig. 2E may be configured substantially as described with respect to the hybrid electric powertrain 202 described with respect to fig. 2D, except that the all-electric powertrain 260 does not include the internal combustion engine 204. As shown, the full electric powertrain 260 may receive all of its power from the energy storage system 210 and/or the power distribution bus 212. In some embodiments, a plurality of all-electric power assemblies 260 configured as shown in fig. 2E may be electrically coupled to the power distribution bus 212. Such a plurality of all-electric powertrain 260 may define an all-electric propulsion system 262. Additionally, or in the alternative, the all-electric powertrain 260, such as shown in fig. 2E, may itself define an all-electric propulsion system 262, e.g., without requiring an additional all-electric powertrain 260 electrically coupled to the power distribution bus 212.

Referring now to fig. 3A-3D, exemplary operating states of the hybrid electric propulsion system 200 or the all-electric propulsion system 262 are further described. Fig. 3A-3D generally illustrate, by way of example, the hybrid electric propulsion system 200 shown in fig. 2A. The operating states described with reference to fig. 3A-3D may be represented by any propulsion system according to the present disclosure, including the hybrid electric propulsion system 200 and/or the all-electric propulsion system 262 disclosed herein. The following description relates to a hybrid electric propulsion system 200 and may be similarly applied to an all-electric propulsion system.

The hybrid electric propulsion system 200 or the all-electric propulsion system 262 may operate from time to time according to one or more operating conditions. Exemplary operating states may include the electric power consumption operating states described with reference to fig. 3A; the power generation operation state described with reference to fig. 3B; the partial power transfer operating state described with reference to fig. 3C; and full power transmission as described with reference to fig. 3D. The hybrid electric propulsion system 200 or the all-electric propulsion system 262 may exhibit any one or more of such operating states, for example, when operating at any one or more of a nominal speed, a cruising speed, a nominal operating speed, a high power operating speed, and/or a low power operating speed.

Referring to fig. 3A, in some embodiments, the hybrid electric propulsion system 200 may exhibit an operational state including an electric power consuming operational state. As shown in FIG. 3A, the electric power consumption operating state includes net electric power consumption from the energy storage system 210, such as by a respective one of the plurality of hybrid electric powertrains 202. The net electrical power consumption from the energy storage system 210 is illustrated in fig. 3A by shaded arrows leading from the energy storage system 210 to respective ones of the plurality of hybrid electric powertrain 202, showing the net electrical power flow from the energy storage system 210 to the plurality of hybrid electric powertrain 202.

In some embodiments, during operating conditions including an electric power consuming operating condition, at least a portion of the power output to the propeller 208 of the respective hybrid electric powertrain 202 may be provided by the corresponding electric machine 206. For example, a first portion of the power output to the propeller 208 may be provided by the corresponding internal combustion engine 204 and a second portion of the power output to the propeller 208 may be provided by the corresponding electric motor 206. In some embodiments, all power output to the propeller may be provided by the corresponding motor 206 during the electric power consuming operational state. In some embodiments, the electric power consuming operational state may include operating the respective hybrid electric powertrain 202 at a nominal speed. For example, the internal combustion engine 204 and/or the electric machine 206 may operate at or near a rated speed. For example, the electric power consumption operational state may correspond to the aircraft 100 performing a takeoff or climb maneuver. In some embodiments, the respective hybrid electric powertrain 202 may draw a relatively large amount of electrical power from the energy storage system 210, such as up to a threshold level of electrical power. The respective power control unit 214 may limit the supplied electrical power from the energy storage system 210 to a threshold level. The threshold level may correspond to a power discharge capacity of the energy storage system 210, for example, when the energy storage system 10 is operating normally and/or includes an operating margin selected to avoid damage to the energy storage system 210. For example, the respective power control units 214 may limit the supply of electrical power to the corresponding electric motors 206 based at least in part on a threshold level corresponding to the power discharge capacity of the energy storage system 210. Such limitations may occur, for example, during electrical power consuming operational states.

Referring to fig. 3B, in some embodiments, the hybrid electric propulsion system 200 may exhibit an operating state that includes a power generation operating state. As shown in FIG. 3B, the power generation operating state includes net power generation by the plurality of hybrid electric powertrains 202, for example, supplied to the energy storage system 210. The net electrical power consumption of the plurality of hybrid electric powertrain 202 is illustrated in fig. 3B by shaded arrows leading from respective ones of the plurality of hybrid electric powertrain 202 to the energy storage system 210, showing the net electrical power flow from the plurality of hybrid electric powertrain 202 to the energy storage system 210.

In some embodiments, during operating conditions including a power generating operating condition, one or more electric machines 206 corresponding to respective hybrid electric powertrain 202 may generate electric power to be provided to energy storage system 210. In some embodiments, the power generating operating state may include operating the respective motor 206 at or near a rated speed. For example, the respective motor 206 may generate electrical power up to a threshold level. Additionally, or alternatively, the power generation operating state may include supplying electrical power up to a threshold level to the energy storage system 210. The respective power control unit 214 may limit the supply electrical power to the energy storage system 210 to a threshold level. The threshold level may correspond to a power receiving capability (e.g., a charging capability and/or a consuming capability) of the energy storage system 210, for example, when the energy storage system 10 is operating normally and/or includes an operating margin selected to avoid damage to the energy storage system 210. For example, the respective power control units 214 may limit the electrical power generated by the corresponding electric motors 206 based at least in part on a threshold level corresponding to the power receiving capability of the energy storage system 210. For example, such limitations may occur during power generation operating conditions.

Referring to fig. 3C, in some embodiments, the hybrid electric propulsion system 200 may exhibit an operating state that includes a partial power transfer operating state. As shown in fig. 3C, the partial power transfer operating state includes transferring a portion of the power generated by the one or more transfer hybrid electric powertrains 202 to one or more receiving hybrid electric powertrains 202 of the hybrid electric propulsion system 200. For example, as shown in fig. 3C, during a partial power transfer operating state, the first hybrid electric powertrain 202a may receive electric power generated by the second hybrid electric powertrain 202b, such as by the second internal combustion engine 204 b. A first portion of the power generated by the second hybrid electric powertrain 202b may be used to rotate the second propeller 208b and a second portion of the power generated by the second hybrid electric powertrain 202b may be transmitted to the first hybrid electric powertrain 202. The partial power transfer from the second hybrid electric powertrain 202b is shown in fig. 3C by the hatched arrow leading from the second hybrid electric powertrain 202b to the first hybrid electric powertrain 202a, showing the net electric power flow from the second hybrid electric powertrain 202b to the first hybrid electric powertrain 202 a.

In some embodiments, during operating conditions including partial power transfer operating conditions, at least one electric machine 206 corresponding to a respective hybrid electric powertrain 202 may generate electric power, and at least one other electric machine 206 corresponding to a respective at least one other hybrid electric powertrain 202 may consume electric power, e.g., to provide mechanical power for rotating a corresponding one or more propellers 208. All or a portion of the electrical power generated by at least one motor 206 may be supplied to at least one other motor 206. In some embodiments, a portion of the electrical power generated by the at least one electric machine 206 may be supplied to the energy storage system 210. Additionally, or in the alternative, the electrical power generated by at least one motor 206 may constitute all or a portion of the electrical power consumed by at least one other motor 206. In some embodiments, a portion of the electrical power consumed by at least one other electric machine 206 may be supplied by the energy storage system 210.

Referring to fig. 3D, in some embodiments, the hybrid electric propulsion system 200 may exhibit an operating state that includes a full power transfer operating state. As shown in fig. 3D, the full power transfer operating state includes the full transfer of power generated by the one or more transmitting hybrid electric powertrains 202 to the one or more receiving hybrid electric powertrains 202 of the hybrid electric propulsion system 200. For example, as shown in fig. 3D, during a full power transfer operating state, the first hybrid electric powertrain 202a may transfer all of the power generated by the first hybrid electric powertrain 202a as electric power to the second hybrid electric powertrain 202b. The full power transfer may include any desired power level of the corresponding transfer hybrid electric powertrain 202, such as a portion of a maximum power generation capacity and/or a maximum power generation capacity of the transfer hybrid electric powertrain 202. In some embodiments, no more than a negligible amount (e.g., none) of the power generated by the first hybrid electric powertrain 202a may be transferred to the first propeller 208a during the full power transfer operating state. Additionally, or in the alternative, rotation of the first propeller 208a may facilitate power generation of the first hybrid electric powertrain 202 a. In fig. 3D, full power transfer to the second hybrid electric powertrain 202b is shown by the hatched arrow leading from the first hybrid electric powertrain 202a to the second hybrid electric powertrain 202b, illustrating the net electric power flow from the first hybrid electric powertrain 202a to the second hybrid electric powertrain 202b.

The respective power control units 214 may limit the electrical power generated by the corresponding electric machines 206 to a threshold level, e.g., corresponding to a power receiving capacity (e.g., a charging capacity and/or a consuming capacity) of the energy storage system 210. Such limitations may occur, for example, during partial power transfer operating states and/or full power transfer operating conditions. In this manner, the respective power control unit 214 may protect the energy storage system 210 from damage that may otherwise occur due to excessive supply of electrical power to the energy storage system 210, for example, in the event of an increase in the amount of power generation and/or a decrease in the electrical power consumption of one of the electric machines 206. Additionally, or in the alternative, the respective power control units 214 may limit the electrical power consumption of the corresponding electric machines 206 to a threshold level, e.g., corresponding to the power discharge capacity of the energy storage system 210. Such limitations may occur, for example, during partial power transfer operating states and/or full power transfer operating conditions. In this manner, the respective power control unit 214 may protect the energy storage system 210 from damage that may otherwise occur due to excessive supply of electrical power to the energy storage system 210, for example, in the event of an increase in the amount of power generation and/or a decrease in the electrical power consumption of one of the electric machines 206.

Referring now to fig. 4, an exemplary power control module 400 is described. The power control module 400 may be used to control the respective hybrid electric powertrain 202 and/or the respective all-electric powertrain 260. The following description relates to a hybrid electric propulsion system 200 and may be similarly applied to an all-electric propulsion system. The power control module 400 may be incorporated into the power control unit 214 and/or used by the power control unit 214, such as the electronic controller 218 of the power control unit 214. The plurality of power control units 214, e.g., electronic controllers 218 thereof, corresponding to respective ones of the plurality of hybrid electric powertrains 202 may each include a power control module 400 configured in accordance with the present disclosure.

For example, with further reference to fig. 2A, a first power control unit 214a corresponding to the first hybrid electric powertrain 202A may include a first electronic controller 218a, the first electronic controller 218a including a first power control module 400. The first power control unit 214a and/or the first electronic controller 218a may utilize the first power control module 400 to provide the power level command 402 to, for example, the first one or more power management devices 216a and/or the first one or more controllable components 404a associated therewith. Additionally, or in the alternative, the first power control unit 214a and/or the first electronic controller 218a may utilize the first power control module 400 to provide the power level command 402 to one or more other controllable components 404a associated with the first hybrid electric powertrain 202a (such as one or more controllable components 404a associated with the first fuel supply system 238a and/or one or more controllable components 404a associated with the first internal combustion engine 204a and/or the first electric machine 206 a).

The second power control unit 214b corresponding to the second hybrid electric powertrain 202b may include a second electronic controller 218b, the second electronic control unit 218b including a second power control module 400. The second power control unit 214b and/or the second electronic controller 218b may utilize the second power control module 400 to provide the power level command 402 to, for example, the second one or more power management devices 216b and/or the second one or more controllable components 404b associated therewith. Additionally, or in the alternative, the second power control unit 214b and/or the second electronic controller 218b may utilize the second power control module 400 to provide the power level command 402 to one or more other controllable components 404b associated with the second hybrid electric powertrain 202b (such as one or more controllable components 404b associated with the second fuel supply system 238b and/or one or more controllable components 404b associated with the second internal combustion engine 204b and/or the second electric machine 206 b).

As shown in fig. 4, in some embodiments, the power control module 400 may include one or more control limit modules 500. Additionally, or in the alternative, the power control module 400 may include one or more control command modules 600. The control limit module 500 may determine an upper power level control limit 502 (power level UCL) and/or a lower power level control limit 504 (power level LCL) for a respective one of the plurality of hybrid electric powertrains 202. In some embodiments, the control restriction module 500 and/or the power control module 400 may include a capacity allocation module 501. The capacity allocation module 501 may define a portion of the control restriction module 500, or the capacity allocation module 501 may be provided as a separate module. The capacity allocation module 501 may allocate capacity limits 503 of the shared system, which may be controlled by the power control module 400, to the corresponding hybrid electric powertrain 202. In some embodiments, the capacity allocation module 501 may allocate a capacity limit 503 corresponding to the power level of the hybrid electric powertrain 202. Additionally, or in the alternative, the capacity allocation module 501 may allocate the capacity limit 503 to a thrust level, a torque level, and/or one or more other parameters of the hybrid electric powertrain 202. In some embodiments, the capacity limit 503 may be determined for corresponding parameters of the hybrid electric powertrain 202 by way of an upper control limit and/or a lower control limit.

The control limit module 500 may include an upper control limit sub-module 506 and/or a lower control limit sub-module 508. The upper control limit submodule 506 and the lower control limit submodule 508 may be provided as a combined control limit module 500 and/or as separate submodules 506/508. The upper control limit submodule 506 may be configured to determine the capacity limit 503 with respect to an upper limit capacity of a corresponding parameter of the hybrid electric powertrain 202. For example, the upper control limit submodule 506 may determine the power level UCL 502. The power level UCL 502 may represent an upper limit of the power level command 402 determined by the control command module 600 for the power control unit 214 corresponding to the respective hybrid electric powertrain 202. Additionally, or in the alternative, upper control limit submodule 506 may determine an upper control limit for one or more other parameters associated with hybrid electric powertrain 202, such as an upper control limit for a thrust level and/or an upper control limit for a torque level. The upper control limit for the thrust level and/or the upper control limit for the torque level may represent an upper limit for a corresponding control command determined by the control command module 600 for such thrust level or torque level corresponding to the respective hybrid electric powertrain 202.

The lower control limit submodule 508 may be configured to allocate a capacity limit 503 to a lower capacity of a corresponding parameter of the hybrid electric powertrain 202. For example, the lower control limit submodule 508 may determine the power level LCL 504. The power level LCL 504 may represent a lower limit of the power level command 402 determined by the control command module 600 for the power control unit 214 corresponding to the respective hybrid electric powertrain 202. Additionally, or in the alternative, the lower control limit submodule 508 may determine a lower control limit for one or more other parameters associated with the hybrid electric powertrain 202, such as a lower control limit for a thrust level and/or a lower control limit for a torque level. The lower control limit for the thrust level and/or the lower control limit for the torque level may represent a lower limit of a corresponding control command determined by the control command module 600 for such thrust level or torque level corresponding to the respective hybrid electric powertrain 202.

The power control module 400, including the control command module 600, may determine the power level command 402 provided by the power control unit 214 corresponding to the respective hybrid electric powertrain 202 based at least in part on a comparison of the power level request 406 to the power level UCL 502 and/or the power level LCL 504. The power control module 400, including the control command module 600, may determine control commands corresponding to torque level requests and/or thrust level requests corresponding to the respective hybrid electric powertrain 202, for example, based at least in part on the comparison with the respective upper and/or lower control limits.

The control restriction module 500 may determine the power level UCL 502 and/or the power level LCL 504 based at least in part on the aggregate front power level request 408. Additionally, or in the alternative, the capacity allocation module 501 may determine a control limit, such as an upper control limit and/or a lower control limit, based at least in part on the aggregate front power level request 408. The aggregate front power level request 408 may include or represent a sum of one or more power level requests 406 corresponding to one or more other hybrid electric powertrains 202 electrically coupled to the energy storage system 210 and/or otherwise included in the hybrid electric propulsion system 200. One or more other hybrid electric powertrains 202 electrically coupled to the energy storage system 210 and/or otherwise included in the hybrid electric propulsion system 200 may sometimes be referred to as front hybrid electric powertrains 202, respectively, when referring to the respective hybrid electric powertrains 202 and/or one or more features thereof. For example, when referring to the first hybrid electric powertrain 202a and/or one or more features thereof (e.g., when referring to the first power control unit 214a, the first power control module 400a, and/or one or more features thereof), the second hybrid electric powertrain 202b may sometimes be referred to as a front hybrid electric powertrain 202. Additionally, or in the alternative, the first hybrid electric powertrain 202a may sometimes be referred to as a front hybrid electric powertrain 202 when the second hybrid electric powertrain 202b and/or one or more features thereof are referred to (e.g., when the second power control unit 214b, the second power control module 400b, and/or one or more features thereof are referred to). In this manner, it will be understood that the term front face herein refers to one or more subassemblies corresponding to the subassemblies.

One or more power level requests 406 corresponding to one or more front side hybrid electric powertrains 202 (i.e., one or more other hybrid electric powertrains 202 included in the hybrid electric propulsion system 200) may sometimes be referred to as front side power level requests 409, respectively. The front side power level request 409 may include or represent a requested power level for one or more front side hybrid electric powertrain 202 electrically coupled to the energy storage system 210 and/or otherwise included in the hybrid electric propulsion system 200.

For example, when referring to the first hybrid electric powertrain 202a and/or one or more features thereof, the power level request 406 of the second hybrid electric powertrain 202b may sometimes be referred to as a first front power level request 409a. The first aggregate front power level request 408a may include or represent a first front power level request 409a for electrically coupling to the energy storage system 210 and/or otherwise including one or more first front hybrid electric powertrains 202 in the hybrid electric propulsion system 200. The first front power level request 409a may be used by the first control limit module 500a to determine the first power level UCL 502a and/or the first power level LCL 504a of the first hybrid electric powertrain 202 a. Additionally, or in the alternative, when the second hybrid electric powertrain 202b and/or one or more features thereof are involved, the power level request 406 of the first hybrid electric powertrain 202a may sometimes be referred to as a second front power level request 409b. The second aggregate front power level request 408b may include or represent a second front power level request 409b for electrically coupling to the energy storage system 210 and/or otherwise including one or more second front hybrid electric powertrains 202 in the hybrid electric propulsion system 200. The second front power level request 409b may be used by the second control limit module 500b to determine the second power level UCL 502b and/or the second power level LCL 504b of the second hybrid electric powertrain 202 b. As shown, the respective control limit module 500 may determine the power level UCL 502 and/or the power level LCL 504 corresponding to the respective hybrid electric powertrain 202 based at least in part on (n) front power level requests 409 corresponding to respective ones of the hybrid electric powertrains 202 (i.e., other one or more hybrid electric powertrains 202 included in the hybrid electric propulsion system 200). Aggregate front power level request 408 may include a sum of (n) front power level requests 409.

In some embodiments, the first control restriction module 500a may determine the first power level UCL 502a and/or the first power level LCL 504a based at least in part on the first aggregate front power level request 408 a. The first aggregate front power level request 408a may include a first front power level request 409a (i.e., a second power level request 406b corresponding to the second power control unit 214b of the second hybrid electric powertrain 202b included in the hybrid electric propulsion system 200). The first aggregate front power level request 408a may include a sum of first (n) first front power level requests 409a. The sum of the first (n) first front power level requests 409a may include the first front power level request 409a. The first power level request 406a is not a front power level request 409 for the first control limit module 500a, and as such, the sum of the first (n) first front power level requests 409a does not include the first power level request 406a.

In some embodiments, the second control restriction module 500b may determine the second power level UCL 502b and/or the second power level LCL 504b based at least in part on the second aggregate front power level request 408 b. The second aggregate front power level request 408b may include a second front power level request 409b (i.e., a first power level request 406a corresponding to the first power control unit 214a of the first hybrid electric powertrain 202a included in the hybrid electric propulsion system 200). The second aggregate front power level request 408b may include a sum of the second (n) second front power level requests 409b. The sum of the second (n) second front power level requests 409b may include the second front power level request 409b. The second power level request 406b is not a front power level request 409 for the second control limit module 500b, and thus, the sum of the second (n) second front power level requests 409b does not include the second power level request 406b.

Still referring to fig. 4, the control command module 600 corresponding to the respective power control unit 214 may determine the power level command 402 based at least in part on the plurality of power level requests 406 corresponding to the hybrid electric powertrain 202 corresponding to the respective power control unit 214. The power level command 402 may additionally be determined based at least in part on the power level UCL502 and/or the power level LCL 504. The control command module 600 may determine the power level command 402 based at least in part on the plurality of power level requests 406, and the control limit module 500 may determine the power level UCL502 and the power level LCL 504 based on the aggregate front power level request 408 (e.g., based on one or more front power level requests 409).

For example, with further reference to fig. 2A, the first power control unit 214a corresponding to the first hybrid electric powertrain 202A may include a first control command module 600a configured to determine the first power level command 402A, and the second power control unit 214b corresponding to the second hybrid electric powertrain 202b may include a second control command module 600b configured to determine the second power level command 402b. The first control command module 600a may determine the first power level command 402a based at least in part on a first power level request 406a corresponding to a first power control unit 214a of a first hybrid electric powertrain 202a included in the hybrid electric propulsion system 200. In addition to the first power level request 406a, the first control command module 600a may determine the first power level command 402a based at least in part on the first power level UCL502 a and/or the second power level LCL 504 a. The second control command module 600b may determine the second power level command 402b based at least in part on a second power level request 406b corresponding to a second power control unit 214b of a second hybrid electric powertrain 202b included in the hybrid electric propulsion system 200. In addition to the second power level request 406b, the second control command module 600b may determine the second power level command 402b based at least in part on the second power level UCL502 b and/or the second power level LCL 504 b.

The power level request 406 may be generated by the input device 220, such as a thrust lever, a power lever, an automatic throttle system, or the like. The input device 220 may provide a power level request 406 corresponding to one or more of the respective hybrid electric powertrains 202. The electronic controller 218 and/or the power control unit 214 corresponding to the respective hybrid electric powertrain 202 may receive the power level request 406, for example, from the input device 220. For example, in some embodiments, the input device 220 may provide a power level request 406 corresponding to a respective hybrid powertrain of the plurality of hybrid powertrains 202. Additionally, or in the alternative, in some embodiments, a first input device 220a corresponding to the first hybrid electric powertrain 202a may provide a first power level request 406a, for example, to the first power control module 400 a. The second input device 220b corresponding to the second hybrid electric powertrain 202b may, for example, provide a second power level request 406b to the second power control module 400 b. Hybrid propulsion system 200 may include one or more input devices 220 including, for example, one or more input devices configured to provide power level requests 406 corresponding to respective ones of (n) plurality of hybrid electric powertrains 202.

Referring now to fig. 5A and 5B, an exemplary control limit module 500 and capacity allocation module 501 are further described. The control limit module 500 and/or the capacity allocation module 501 shown in fig. 5A and/or 5B may be included in a respective one of the plurality of power control modules 400 that corresponds to one of the plurality of hybrid electric powertrain 202 and/or the all-electric powertrain 260, respectively. For example, a first power control module 400a corresponding to a first hybrid electric powertrain 202a may include a first control limit module 500a and/or a first capacity allocation module 501a, and a second power control module 400b corresponding to a second hybrid electric powertrain 202b may include a second control limit module 500b and/or a second capacity allocation module 501b. The first control limit module 500a and/or the second control limit module 500B may be configured as shown in fig. 5A and/or 5B, for example. Additionally, or in the alternative, the first capacity allocation module 501a and/or the second capacity allocation module 501B may be configured as shown in fig. 5A and/or 5B, for example.

Referring to FIG. 5A, an exemplary control limit module 500 is depicted that includes a capacity allocation module 501. As shown, the capacity allocation module 501 may determine the capacity limit 503 based at least in part on the aggregate front power level request 408. The capacity limit 503 may include an upper and/or lower control limit, such as a power level UCL 502 and/or a power level LCL504. The capacity allocation module 501 may include a capacity level operator 505 that determines a capacity limit 503 based on available capacity 507 or allocated capacity 509. The available capacity 507 may be determined based at least in part on the aggregate front power level 408. The allocation capacity 509 may be determined based at least in part on the allocation factor 511. The allocation factor 511 may represent a factor used to determine an allocation of the total capacity of the shared system of the respective hybrid powertrain 202. The allocation of the total capacity of the shared system may be determined proportionally or disproportionately based on the number of hybrid electric powertrain 202 in the hybrid electric propulsion system 200. For example, at least some of the respective control limit modules 500 corresponding to the respective hybrid electric powertrain 202 may have equal split factors 511. Additionally, or in the alternative, at least some of the respective control limit modules 500 corresponding to the respective hybrid electric powertrain 202 may have respectively different split factors 511. In some embodiments, the partitioning factor 511 may be determined based at least in part on the inverse (multiplicative inverse) of the total number of hybrid electric powertrains 202 electrically coupled to the energy storage system 210.

In some embodiments, the capacity level operator 505 may select between the available capacity 507 and the allocated capacity 509. In some embodiments, the control limit operator 505 may determine the capacity limit 503 based at least in part on the greater of the available capacity 507 and the allocated capacity 509. The capacity limit 503 determined based on the larger of the available capacity 507 and the allocated capacity 509 may be an upper control limit. Additionally, or in the alternative, in some embodiments, the control limit operator 505 may determine the capacity limit 503 based at least in part on the smaller of the available capacity 507 and the allocated capacity 509. The capacity limit 503 determined based on the smaller of the available capacity 507 and the allocated capacity 509 may be a lower control limit.

Referring to fig. 5B, control limit module 500 may include an upper control limit sub-module 506 and a lower control limit sub-module 508 such that control limit module 500 may determine power level UCL502 and/or power level LCL 504. The upper control limit submodule 506 and/or the lower control limit submodule 508 may each include a capacity allocation module 501. In some embodiments, the upper control limit submodule 506 and the lower control limit submodule 508 may be provided as separate modules, for example, in a separate control limit module 500. Alternatively, as shown, the control limit module 500 may include an upper control limit sub-module 506 configured to determine the power level UCL502 and a lower control limit sub-module 508 configured to determine the power level LCL 504.

In some embodiments, the control limit module 500 may set the power level UCL 502 to a value equal to the available discharge power capacity 510. Additionally, or in the alternative, the control limit module 500 may set the power level UCL 502 to a value equal to the allocated discharge power capacity 512. In some embodiments, the control restriction module 500 may determine the power level UCL 502 based at least in part on a greater value between the available discharge power capacity 510 and the allocated discharge power capacity 512. The larger value between the available discharge power capacity 510 and the allocated discharge power capacity 512 may be determined by an upper limit comparator operator 514 configured to determine the larger value between the two. If the corresponding values are equal, the upper limit comparator operator 514 may default to the available discharge power capacity 510 or the allocated discharge power capacity 512.

The available discharge power capacity 510 may include or define an amount of electrical power available for discharge after subtracting the aggregate front power level request 408 from the power discharge threshold 518. The aggregate front power level request 408 may include a total (e.g., sum) of one or more front power level requests 409 (fig. 4) that respectively correspond to the front hybrid electric powertrain 202. In other words, the available discharge power capacity 510 may include or define a difference resulting from subtracting one or more front side power level requests 409 from the power discharge threshold 518. The power discharge threshold 518 may include or define a threshold level for discharging electrical power from the energy storage system 210. The threshold level may correspond to a power discharge capability of the energy storage system 210, for example, when the energy storage system 210 is operating normally and/or includes an operating margin selected to avoid damage to the energy storage system 210. The resulting difference of subtracting the aggregate front power level request 408 from the power discharge threshold 518 may be determined by an available discharge capacity comparator operator 520 configured to determine such a difference and/or perform such a subtraction operation. If the corresponding values are equal, the available discharge capacity comparator operator 520 may default to aggregate the front power level request 408 or the power discharge threshold 518.

The distributed discharge power capacity 512 may include or define an allocation of total power discharge capacity of the energy storage systems 210 allocated to the respective hybrid electric powertrain 202. The total power discharge capacity of the energy storage system 210 may be defined by a power discharge threshold 518. The allocated discharge power capacity 512 may be determined based at least in part on an allocation of the power discharge threshold 518 to the corresponding hybrid electric powertrain 202. In some embodiments, the allocated discharge power capacity 512 may be determined based at least in part on a product of the allocation factor 511 and the power discharge threshold 518. The allocation of the total power discharge capacity of the energy storage systems 210 of the respective hybrid electric powertrain 202 may be determined proportionally or disproportionately based on the number of hybrid electric powertrain 202 in the hybrid electric propulsion system 200. For example, at least some of the respective control limit modules 500 corresponding to the respective hybrid electric powertrain 202 may have equal split factors 511 such that the respective control limit modules 500 may determine equal split discharge power capacities 512. Additionally, or in the alternative, at least some of the respective control limit modules 500 corresponding to the respective hybrid electric powertrain 202 may have respectively different distribution factors 511 such that the respective control limit modules 500 may determine respectively different distributed discharge power capacities 512. In some embodiments, the split factor 511 may be determined based at least in part on the inverse of the total number of hybrid electric powertrains 202 electrically coupled to the energy storage system 210. The allocation of the total power discharge capacity of the energy storage system 210 of the respective hybrid powertrain 202 may be determined by an allocation discharge operator 524 configured to reduce the power discharge threshold 518 by an allocation factor 511. For example, the allocation discharge operator 524 may multiply the power discharge threshold 518 by an allocation factor 511.

In some embodiments, the available discharge power capacity 510 and/or the allocated discharge power capacity 512 may be reduced by losses on the hybrid electric propulsion system 200 associated with discharging from the energy storage system 210 and/or transmitting power to the respective hybrid electric powertrain 202. Such losses may include and/or be attributable to electrical power transfer on the hybrid electric powertrain 202, effects of parasitic elements (e.g., resistance, capacitance, and inductance), skin effects, resistive heating, magnetic losses due to eddy currents, hysteresis, dielectric losses, corona discharge, and other effects. In some embodiments, for example, the power discharge loss 526 may be added to the aggregate front power level request 408 by an adder 528. Additionally, or in the alternative, the power discharge threshold 518 may be reduced by a discharge loss factor 530, such as by a multiplier 532.

Still referring to fig. 5B, the control restriction module 500 may determine the power level LCL 504. In some embodiments, the control restriction module 500 may set the power level LCL 504 to a value equal to the available storage power capacity 534. Additionally, or in the alternative, control restriction module 500 may set power level LCL 504 to a value equal to allocated storage power capacity 536. In some embodiments, control restriction module 500 may determine power level LCL 504 based at least in part on a smaller value between available storage power capacity 534 and allocated storage power capacity 536. The smaller value between the available storage power capacity 534 and the allocated storage power capacity 536 may be determined by a lower limit comparator operator 538 configured to determine the smaller value between the two. If the corresponding values are equal, the lower limit comparator operator 538 may default to the available storage power capacity 534 or the allocated storage power capacity 536.

The available storage power capacity 534 may include or define a difference resulting from subtracting the aggregate front power level request 408 from the charge threshold 540. In other words, the available storage power capacity 534 may include or define an amount of electrical power capacity available for storage after subtracting one or more front side power level requests 409 from the charge threshold 540. The charge threshold 540 may include or define a threshold level for supplying electrical power to the energy storage system 210. The threshold level may correspond to a charging capability of the energy storage system 210, for example, when the energy storage system 210 is operating normally and/or includes an operating margin selected to avoid damage to the energy storage system 210. The difference resulting from subtracting the aggregate front power level request 408 from the charge threshold 540 or subtracting the aggregate front power level request 408 from the charge threshold 540 may be determined by an available storage capacity comparator operator 542 configured to determine such a difference and/or perform such a subtraction operation. If the corresponding values are equal, the available storage capacity comparator operator 542 may default to the aggregate front power level request 408 or the charge threshold 540.

The allocated storage power capacity 536 may include or define an allocation of the total charge capacity of the energy storage system 210 allocated to the respective hybrid electric powertrain 202. The total charge capacity of the energy storage system 210 may be defined by a charge threshold 540. The allocated storage power capacity 536 may be determined based at least in part on the allocation of the charge threshold 540 to the corresponding hybrid electric powertrain 202. In some embodiments, allocated storage power capacity 536 may be determined based at least in part on the product of allocation factor 511 and charge threshold 540. The allocation of the total charge capacity of the energy storage system 210 of the respective hybrid electric powertrain 202 may be determined proportionally or disproportionately based on the number of hybrid electric powertrains 202 in the hybrid electric propulsion system 200. For example, at least some of the respective control limit modules 500 corresponding to the respective hybrid electric powertrain 202 may have equal split factors 511 such that the respective control limit modules 500 may determine equal split storage power capacities 536. Additionally, or in the alternative, at least some of the respective control limit modules 500 corresponding to the respective hybrid electric powertrain 202 may have respective different distribution coefficients 511 such that the respective control limit modules 500 may determine respective different distributed storage power capacities 536.

The allocation of the total charge capacity of the energy storage systems 210 of the respective hybrid electric powertrain 202 may be determined by an allocation storage operator 544 configured to reduce the charge threshold 540 by an allocation factor 511. For example, allocation store operator 544 may multiply charge threshold 540 by allocation factor 511. In some embodiments, the split factor 511 may provide the same value for determining the split storage power capacity 536 and the split discharge power capacity 512 of the respective hybrid electric powertrain 202. Additionally, or in the alternative, the split factors 511 may each provide a different value for determining the split storage power capacity 536 and the split discharge power capacity 512 of the corresponding hybrid electric powertrain 202. In some embodiments, the available storage power capacity 534 and/or the distributed discharge power capacity 512 may be reduced by losses on the hybrid electric propulsion system 200 associated with supplying electric power to the energy storage system 210 and/or transmitting power from the respective hybrid electric powertrain 202 and/or increased by gains thereon. In some embodiments, the charge threshold 540 may be increased by the discharge loss factor 530, for example by the division operator 546.

Referring now to FIG. 6, an exemplary control command module 600 is further described. The control command module 600 shown in fig. 6 may be included in a respective one of the plurality of power control modules 400 corresponding to one of the plurality of hybrid electric powertrains 202 and/or the full electric powertrains 260, respectively. For example, a first power control module 400a corresponding to a first hybrid powertrain 202a may include a first control command module 600a and a second power control module 400b corresponding to a second hybrid powertrain 202b may include a second control command module 600b. The first control command module 600a and/or the second control command module 600b may be configured as shown in fig. 6, for example.

The control command module 600 may determine a power level command 402 between a power level UCL 502 and a power level LCL 504. When the power level request 406 is between the power level UCL 502 and the power level LCL 504, the control command module 600 may set the power level command 402 equal to the power level request 406. Additionally, or in the alternative, when the power level request 406 is greater than the power level UCL 502, the control command module 600 may set the power level command 402 equal to the power level UCL 402. Additionally, or in the alternative, when the power level request 406 is less than the power level LCL 504, the control command module 600 may set the power level command 402 equal to the power level LCL 404.

In some embodiments, control command module 600 may determine whether power level request 406 is greater than power level UCL 502, for example, by comparing power level request 406 to power level UCL 402. The comparison may be performed by the power level request upper limit comparator 602. The power level request upper limit comparator 602 may determine whether the power level request 406 is greater than the power level UCL 502. Additionally, or in the alternative, in some embodiments, control command module 600 may determine whether power level request 406 is less than power level LCL 404, for example, by comparing power level request with power level LCL 504. The comparison may be performed by the power level request lower limit comparator 604. The power level request lower limit comparator 604 may determine whether the power level request 406 is less than the power level LCL 504.

As shown in fig. 6, when the power level request 406 has a value between the power level UCL 502 and the power level LCL 504, the control command module 600 may determine the power level command 402 corresponding to (e.g., equal to) the power level request 406. Additionally, or in the alternative, when the power level request 406 has a value greater than the power level UCL 502, the control command module 600 may determine the power level command 402 corresponding to (e.g., equal to) the power level UCL 502. Additionally, or in the alternative, when the power level request 406 has a value less than the power level LCL 504, the control command module 600 may determine the power level command 402 corresponding to (e.g., equal to) the power level LCL 504.

For example, as shown in fig. 6, when the power level request upper limit comparator 602 determines that the power level request 406 is greater than the power level UCL 502, the control command module 600 may determine the power level command 402 corresponding to (e.g., equal to) the power level UCL 502, as shown in block 606. Additionally, or in the alternative, when the power level request lower limit comparator 604 determines that the power level request 406 is less than the power level LCL504, the control command module 600 may determine a power level command 402 corresponding to (e.g., equal to) the power level LCL504, as shown in block 608. Additionally, or in the alternative, when the power level request 406 is neither greater than the power level UCL 502 nor less than the power level LCL504, the control command module 600 may determine a power level command 402 corresponding to (e.g., equal to) the power level request 406, as shown in block 610. The power control module 400 (fig. 4) may output the power level command 402 determined by the control command module 600. For example, the power control module 400 (fig. 4) may output the power level command 402 to one or more controllable components 404.

In some embodiments, control command module 600 may perform the comparison of power level request 406 with power level UCL 502, such as by power level request upper limit comparator 602, and the comparison of power level request 406 with power level LCL504, such as by power level request lower limit comparator 604, simultaneously or sequentially. The sequential comparison of the power level request 406 with the power level UCL 502 and the comparison of the power level request 406 with the power level LCL504 may be performed in any order. For example, as shown in fig. 6, control command module 600 may compare power level request 406 to power level UCL 502, and when power level request 406 is not greater than power level UCL 502, control command module 600 may continue to compare power level request 406 to power level LCL 504.

Referring now to fig. 7A and 7B, in some embodiments, power discharge threshold 518 may be determined based at least in part on power discharge coefficient 700, as shown in fig. 7A, and/or charge threshold 540 may be determined based at least in part on charge coefficient 702, as shown in fig. 7B.

Fig. 7A shows a power discharge coefficient curve 704 that provides a power discharge coefficient 700 as a function of a state of charge 706 of the energy storage system 210. The power discharge threshold 518 may reflect an adjustment based on the power discharge coefficient 700, such as determined based on the power discharge coefficient curve 704 shown in fig. 7A. As shown, the power discharge coefficient 700 may have a maximum value when the state of charge 706 is above a state of charge upper threshold (e.g., a state of charge corresponding to a maximum power discharge coefficient, "d_max"). When state of charge 706 is below a state of charge threshold (e.g., a state of charge corresponding to a minimum power discharge coefficient, "D Min"), power discharge coefficient 700 may have a minimum value. The power discharge coefficient 700 may have a value between a minimum value and a maximum value when the state of charge is between the state of charge lower threshold (D Min) and the state of charge upper threshold (D Max). The power discharge coefficient 700 may be determined based at least in part on the power discharge coefficient curve 704, e.g., based at least in part on a slope of the power discharge coefficient curve 704.

In some embodiments, as shown, the power discharge coefficient 700 may have a value of 1.0 when the state of charge 706 is above the upper state of charge threshold (d_max). Additionally, or in the alternative, the power discharge coefficient 700 may have a value of 0.0 when the state of charge 706 is below the state of charge threshold (D Min). Additionally, or in the alternative, the power discharge coefficient 700 may have a value between 0.0 and 1.0 when the state of charge 706 is between the state of charge lower threshold (D Min) and the state of charge upper threshold (D Max). The power discharge threshold 518 may be determined based at least in part on the nominal power discharge threshold multiplied by the power discharge coefficient 700.

Fig. 7B shows a charge coefficient curve 708 that provides the charge coefficient 702 as a function of the state of charge 706 of the energy storage system 210. The charge threshold 540 may reflect an adjustment based on the charge coefficient 702, such as determined based on the charge coefficient curve 708 shown in fig. 7B. As shown, when state of charge 706 is below a state of charge threshold (e.g., a state of charge "c_min" corresponding to a minimum charge coefficient (e.g., a maximum negative charge coefficient)), charge coefficient 702 may have a minimum value (e.g., a maximum negative value). When state of charge 706 is above a state of charge upper threshold (e.g., a state of charge, "c_max" corresponding to a maximum charge coefficient (e.g., a minimum negative charge coefficient), charge coefficient 702 may have a maximum value (e.g., a minimum negative value). The charge coefficient 702 may have a value between a minimum value and a maximum value when the state of charge is between the state of charge lower threshold (c_min) and the state of charge upper threshold (c_max). The charging coefficient 702 may be determined based at least in part on the charging coefficient curve 708, for example based at least in part on the slope of the charging coefficient curve 706.

In some embodiments, as shown, the charge coefficient 702 may have a value of-1.0 when the state of charge 706 is below a state of charge lower threshold (C min). Additionally, or in the alternative, the charge coefficient 702 may have a value of 0.0 when the state of charge 706 is above the upper state of charge threshold (c_max). Additionally, or in the alternative, the charge coefficient 702 may have a value between-1.0 and 0.0 when the state of charge 706 is between the state of charge lower threshold (c_min) and the state of charge upper threshold (c_max). The charge threshold 540 may be determined based at least in part on multiplying the nominal charge threshold by the charge coefficient 702.

Referring now to fig. 8A-8D, an exemplary method is described with reference to flowchart 800. As shown, the exemplary method may include controlling the hybrid electric propulsion system 200, the all-electric propulsion system 262, the hybrid electric powertrain 202, and/or the all-electric powertrain 260. As shown in FIG. 8A, an exemplary method may include, at block 802 of flowchart 800, determining a power level UCL of a hybrid electric powertrain electrically coupled to an energy storage system. The power level UCL may correspond to the difference between the aggregate front power level request and the power discharge threshold. At block 804, an exemplary method may include determining a power level LCL of the hybrid electric powertrain. The power level LCL may correspond to a difference between the aggregate frontal power level request and the charge threshold. At block 806, the example method may include determining a power level command for the hybrid electric powertrain. The power level command may be determined based at least in part on the power level UCL and/or the power level LCL.

In some embodiments, the exemplary method may include, at block 808 of flowchart 800, providing a power level command to one or more power management devices. The one or more power management devices may define at least a portion of a power control unit for the hybrid electric powertrain. Additionally, or in the alternative, at block 810, the example method may include receiving, at an electronic controller, a power level request for a hybrid electric powertrain. The electronic controller may be incorporated into and/or communicatively coupled with a power control unit for the hybrid electric powertrain. Additionally, or in the alternative, at block 810, the example method may include receiving, at the electronic controller, an aggregate front power level request and/or a requested power level for one or more front hybrid electric powertrains.

Referring to fig. 8B, in some embodiments, determining the power level UCL at block 802 (fig. 8A) may include determining an available discharge power capacity at block 814. The available discharge power capacity may include a difference resulting from subtracting (i) the aggregate front power level request from (ii) the power discharge threshold. The aggregate front side power level request may include a requested power level of one or more front side hybrid electric powertrains electrically coupled to the energy storage system. The power discharge threshold may include a threshold level for discharging from the energy storage system. Additionally, or in the alternative, determining the power level UCL at block 802 (fig. 8A) may include determining an allocated discharge power capacity at block 816. Distributing the discharge power capacity may include distributing a power discharge threshold of the hybrid electric powertrain. Additionally, or in the alternative, determining the power level UCL at block 802 (fig. 8A) may include setting the power level UCL equal to (i) the available discharge power capacity or (ii) the allocated discharge power capacity at block 818. For example, the power level UCL may be set to the greater of (i) the available discharge power capacity and (ii) the allocated discharge power capacity.

Referring to fig. 8C, in some embodiments, determining a lower power level control limit at block 804 (fig. 8A) may include determining an available storage power capacity at block 820. The available storage power capacity may include a difference resulting from subtracting (i) the aggregate front power level request from (ii) the charge threshold. The charge threshold may include a threshold level for supplying electrical power to the energy storage system. Additionally, or in the alternative, determining the power level LCL at block 804 (fig. 8A) may include determining an allocated storage power capacity at block 822. Allocating storage power capacity may include allocating a charge threshold for the hybrid electric powertrain. Additionally, or in the alternative, determining the power level LCL at block 804 (fig. 8A) may include setting the power level LCL equal to the lesser of (i) the available storage power capacity and (ii) the allocated storage power capacity at block 824.

Referring to fig. 8D, in some embodiments, determining the power level command for the hybrid electric powertrain at block 806 (fig. 8A) may include, at block 826, limiting the power level command by the power level UCL and/or the power level LCL. In some embodiments, limiting the power level command by the power level UCL and/or the power level LCL may include, at block 828, setting the power level command equal to the power level request when the power level request is between the power level UCL and the power level LCL. Additionally, or in the alternative, limiting the power level command by the power level UCL may include, at block 830, setting the power level command equal to the power level UCL when the power level request of the hybrid electric powertrain is greater than the power level UCL. Additionally, or in the alternative, limiting the power level command by the power level LCL may include, at block 832, setting the power level command equal to the power level LCL when the power level request is less than the power level LCL.

Referring to fig. 8E, in some embodiments, the exemplary method may include, as shown at block 834 of flowchart 800, generating electrical power using the hybrid electric powertrain and/or converting the electrical power to mechanical power based at least in part on the power level command. Additionally, or in the alternative, the exemplary method may include, at block 836, generating mechanical power using the hybrid electric powertrain based at least in part on the power level command, and providing the mechanical power to the one or more propellers. Additionally, or in the alternative, the exemplary method may include, at block 838, providing electrical power from the hybrid electric powertrain to the energy storage system based at least in part on the power level command. Additionally, or in the alternative, the exemplary method may include, at block 840, receiving electrical power from the energy storage system at the hybrid electric powertrain based at least in part on the power level command. Additionally, or in the alternative, the example method may include, at block 842, receiving electrical power from the front hybrid electric powertrain based at least in part on the first power level command.

Referring now to FIG. 9, an exemplary control system 900 is described. In accordance with the present disclosure, the control system 900 may perform any desired control operations. For example, the control system 900 may perform exemplary methods, such as the exemplary methods described with reference to the flowchart 800 shown in fig. 8A-8D. As shown in fig. 9, the exemplary control system 900 may include one or more electronic controllers 218. The respective electronic controllers 218 may monitor and/or control various operations of the respective hybrid electric powertrain 202 and/or the all-electric powertrain 260 as described herein, such as various operations of the respective power control unit 214 and/or the power management device 216 thereof, various operations of the respective fuel supply system 238.

The electronic controller 218 may include one or more computing devices 902 configured to perform specified control operations. The one or more computing devices 902 may include one or more control modules 904 configured to cause the electronic controller 218 to perform one or more control operations, e.g., based at least in part on one or more models, look-up tables, or the like. The one or more control modules 904 may include a power control module 400, a control restriction module 500, and/or a control command module 600.

The one or more computing devices 902 may include one or more processors 906 and one or more memory devices 908. The one or more processors 906 may include any suitable processing device, such as a microprocessor, microcontroller, integrated circuit, logic device, and/or other suitable processing device. The one or more memory devices 908 may include one or more computer-readable media including, but not limited to, non-transitory computer-readable media, RAM, ROM, hard disk drives, flash memory drives, and/or other memory devices 908. The one or more control modules 904 can be implemented at least in part by one or more processors 906 and/or one or more memory devices 908.

As used herein, the terms "processor" and "computer" and related terms, such as "processing device" and "computing device," are not limited to integrated circuits referred to in the art as computers, but broadly refer to microcontrollers, microcomputers, programmable Logic Controllers (PLCs), application specific integrated circuits, and other programmable circuits, and these terms are used interchangeably herein. Memory device 908 may include, but is not limited to, non-transitory computer-readable media such as Random Access Memory (RAM), and computer-readable non-volatile media such as hard drives, flash memory, and other memory devices. Alternatively, a floppy disk, a compact disk read-only memory (CD-ROM), a magneto-optical disk (MOD), and/or a Digital Versatile Disk (DVD) may also be used.

As used herein, the term "non-transitory computer-readable medium" is intended to represent any tangible computer-based device, implemented in any method or technology, for short-term and long-term storage of information, such as computer-readable instructions, data structures, program modules and sub-modules, or other data in any device. The methods described herein may be encoded as executable instructions embodied in a tangible, non-transitory computer-readable medium, including but not limited to storage devices and/or memory devices. Such instructions, when executed by a processor, cause the processor to perform at least a portion of the methods described herein. Furthermore, as used herein, the term "non-transitory computer readable medium" includes all tangible computer readable media, including but not limited to non-transitory computer storage devices, including but not limited to volatile and non-volatile media, and removable and non-removable media, such as firmware, physical and virtual memory, CD-ROMs, DVDs, and any other digital source, such as a network or the internet, and yet to be developed digital means, the only exception being a transient propagated signal.

The one or more memory devices 908 may store information accessible to the one or more processors 906, including computer-executable instructions 910 that may be executed by the one or more processors 906. The instructions 910 may include any set of instructions that, when executed by the one or more processors 906, cause the one or more processors 9060 to perform operations including control operations. The one or more memory devices 908 may store data 912 accessible by the one or more processors 906, such as data associated with the hybrid electric propulsion system 200, the corresponding hybrid electric powertrain 202, the one or more control modules 904, and/or the electronic controller 218 associated therewith. The data 912 may include current or real-time data 912, past data 912, or a combination thereof. The data 912 may be stored in a database 914. The data 912 may also include other data sets, parameters, outputs, information associated with the hybrid electric propulsion system 200, the respective hybrid electric powertrain 202, the one or more control modules 904, and/or the electronic controller 218 associated therewith.

The one or more computing devices 902 may also include a communication interface 916 configured to communicate with various nodes on the communication network 918 via a wired or wireless communication line 920. Communication interface 916 may include any suitable components for interfacing with one or more networks, including, for example, a transmitter, a receiver, a port, a controller, an antenna, and/or other suitable components. The communication network 918 may include, for example, a Local Area Network (LAN), a Wide Area Network (WAN), a SATCOM network, a VHF network, an HF network, a Wi-Fi network, a WiMAX network, a gateway connection network, and/or any other suitable communication network 918 for sending messages to the computing device 902 and/or sending information from the computing device 902 via a communication line 920. The communication lines 920 of the communication network 918 may include a data bus or a combination of wired and/or wireless communication links.

The one or more electronic controllers 218 may be communicatively coupled with one or more components of the hybrid electric propulsion system 200 and/or the corresponding hybrid electric powertrain 202 that the one or more electronic controllers 218 may communicate with via a communication network 918. For example, the electronic controller 218 may be communicatively coupled with the corresponding power control unit 214 and/or its respective power management device 216. Additionally, or in the alternative, the electronic controller 218 may be communicatively coupled with a corresponding input device 220. Additionally, or in the alternative, the electronic controller 218 may be communicatively coupled with a corresponding fuel supply system 238, such as with one or more fuel valves or other controllable components.

The control system 900 may include a management system 922 that is located locally or remotely with respect to the hybrid electric propulsion system 200 and/or with respect to the aircraft 100 powered by the hybrid electric propulsion system 200. The management system 922 may include a server 924 and/or a data warehouse 926. For example, at least a portion of the data 912 may be stored in the data warehouse 926, and the server 924 may send the data 912 from the data warehouse 926 to the one or more electronic controllers 218, and/or receive the data 912 from the one or more electronic controllers 218, and store the received data 912 in the data warehouse 926 for further purposes. The servers 924 and/or data warehouse 926 may be implemented as part of one or more electronic controllers 218 and/or as part of the management system 922. The control system 900 may also include a user interface 928 configured to allow a user to interact with various features of the control system 900, for example, through the communication interface 916. The communication interface 916 may allow the one or more computing devices 902 to communicate with various nodes associated with the aircraft 100, the hybrid electric propulsion system 200, the management system 922, and/or the user interface 928.

Further aspects are provided by the subject matter of the following clauses:

a power control unit for a hybrid electric or all-electric propulsion system of an aircraft, the power control unit comprising: a power control unit electrically coupling the electric machine to the energy storage system; wherein the power control unit comprises an electronic controller comprising a non-transitory computer-readable medium comprising computer-executable instructions, wherein the computer-executable instructions, when executed by a processor associated with the electronic control unit, cause the power control unit to perform a method comprising: determining an upper power level control limit (power level UCL) of the power control unit, wherein the power level UCL corresponds to a difference between an aggregate front power level request and a power discharge threshold; and determining a power level command for the power control unit, the power level command determined based at least in part on the power level UCL, wherein determining the power level command for the power control unit includes limiting the power level command by the power level UCL.

The power control unit of any preceding clause, wherein determining the power level UCL comprises: determining an available discharge power capacity comprising a difference resulting from subtracting (i) the aggregate front side power level request from (ii) the power discharge threshold, the aggregate front side power level request comprising a requested power level of one or more front side hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level of discharge from the energy storage system; and setting the power level UCL equal to the available discharge power capacity.

A power control unit according to any preceding clause, wherein the power control unit comprises one or more power management devices.

The power control unit of any preceding clause, wherein the one or more power management devices comprise at least one of: an inverter, a converter, a rectifier, a synchronous converter, a synchronous buck converter, a bi-directional interleaved converter, an autotransformer rectifier, or a matrix converter.

A hybrid electric or all-electric powertrain for an aircraft, the powertrain comprising: a motor; an energy storage system; and a power control unit electrically coupling the electric machine to the energy storage system; wherein the power control unit comprises an electronic controller comprising a non-transitory computer-readable medium including computer-executable instructions, wherein the computer-executable instructions, when executed by a processor associated with the electronic controller, cause the power control unit to perform a method comprising: determining an upper power level control limit (power level UCL) of the power control unit, wherein the power level UCL corresponds to a difference between an aggregate front power level request and a power discharge threshold; and determining a power level command for the power control unit, the power level command determined based at least in part on the power level UCL, wherein determining the power level command for the power control unit includes limiting the power level command by the power level UCL.

The hybrid electric or all-electric powertrain of any preceding clause, wherein determining the power level UCL comprises: determining an available discharge power capacity comprising a difference resulting from subtracting (i) the aggregate front side power level request from (ii) the power discharge threshold, the aggregate front side power level request comprising a requested power level of one or more front side hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level of discharge from the energy storage system; and setting the power level UCL equal to the available discharge power capacity.

The hybrid electric or all-electric powertrain of any preceding clause, wherein the hybrid electric powertrain comprises a series configuration, a parallel configuration, or a series-parallel configuration.

The hybrid electric or all-electric powertrain of any preceding clause, comprising: an internal combustion engine.

The hybrid electric or all-electric powertrain of any preceding clause, wherein the internal combustion engine comprises a gas turbine engine.

The hybrid electric or all-electric powertrain of any preceding clause, comprising: one or more propellers configured to receive mechanical power from the internal combustion engine and the electric machine, either alone or simultaneously.

The hybrid or all-electric powertrain of any preceding clause, wherein the hybrid electric powertrain, the one or more front side hybrid electric powertrains, and the energy storage system are electrically coupled to a power distribution bus.

The hybrid electric or all-electric powertrain of any preceding clause, wherein the power control unit comprises one or more power management devices comprising at least one of: an inverter, a converter, a rectifier, a synchronous converter, a synchronous buck converter, a bi-directional interleaved converter, an autotransformer rectifier, or a matrix converter.

The hybrid electric or all-electric powertrain of any preceding clause, wherein the requested power level of the one or more front-side hybrid electric powertrains is provided by an input device comprising at least one of: a thrust lever, a power lever, or an automatic throttle system.

The hybrid electric or all-electric powertrain of any preceding clause, wherein the hybrid electric powertrain comprises the power control unit of any preceding clause.

A hybrid electric or all-electric propulsion system for an aircraft, the hybrid electric or all-electric propulsion system comprising: a first hybrid electric powertrain; a second hybrid electric powertrain; and an energy storage system electrically coupled to the first and second hybrid electric powertrains; wherein the first hybrid electric powertrain comprises: a first electric machine and a first power control unit electrically coupling the first electric machine to the energy storage system; wherein the first power control unit comprises a first electronic controller comprising a first non-transitory computer-readable medium comprising first computer-executable instructions that, when executed by a first processor associated with the first electronic controller, cause the first power control unit to perform a first method of controlling the first hybrid electric or all-electric propulsion system.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the first method comprises: determining a first power level UCL of the first hybrid electric powertrain electrically coupled to an energy storage system; and determining a first power level command for the first hybrid electric powertrain, the first power level command determined based at least in part on the first power level UCL.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the first method comprises: determining a first power level LCL of the first hybrid electric powertrain, and determining the first power level command of the first hybrid electric powertrain based at least in part on the first power level LCL.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein the first power level UCL corresponds to a difference between a first aggregate front power level request and a power discharge threshold.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level command of the first hybrid-electric powertrain comprises limiting the first power level command by the first power level UCL.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level UCL comprises: a first available discharge power capacity is determined at least in part by subtracting (i) a first aggregate front side power level request from (ii) a power discharge threshold, the first aggregate front side power level request comprising a first requested power level of one or more first front side hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level of discharge from the energy storage system.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level UCL comprises: a first allocated discharge power capacity is determined, the first allocated discharge power capacity comprising a first allocation of the power discharge threshold for the first hybrid electric powertrain.

The hybrid-electric or all-electric propulsion system of any preceding clause, the first power level UCL being set equal to the greater of (i) the available discharge power capacity and (ii) the first distributed discharge power capacity.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein the first power level LCL corresponds to a difference between the first aggregate front power level request and a charge threshold.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level command of the first hybrid-electric powertrain comprises limiting the first power level command by the first power level LCL.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level LCL comprises: a first available storage power capacity is determined at least in part by subtracting (i) a first aggregate front power level request from (ii) the charge threshold, the charge threshold comprising a threshold level for supplying electrical power to the energy storage system.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level LCL comprises: a first allocated storage power capacity is determined, the first allocated storage power capacity comprising a first allocation of the charge threshold for the first hybrid electric powertrain.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level LCL comprises: the first power level LCL is set to the lesser of (i) an available storage power capacity and (ii) a first allocated storage power capacity.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the first power level command of the first hybrid-electric powertrain comprises limiting the first power level command by the first power level UCL and the first power level LCL.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the second hybrid electric powertrain comprises: a second electric machine and a second power control unit electrically coupling the second electric machine to the energy storage system;

the hybrid electric or all-electric propulsion system of any preceding clause, wherein the second power control unit comprises a second electronic controller comprising a second non-transitory computer-readable medium comprising second computer-executable instructions that, when executed by a second processor associated with the second electronic controller, cause the second power control unit to perform a second method of controlling the second hybrid electric or all-electric propulsion system;

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the second method comprises: determining a second power level UCL of a second hybrid electric powertrain electrically coupled to the energy storage system; and determining a second power level command for a second hybrid electric powertrain, the second power level command determined based at least in part on the second power level UCL.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the second method comprises: a second power level LCL of a second hybrid electric powertrain is determined, and the second power level command of the second hybrid electric powertrain is determined based at least in part on the second power level LCL.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein the second power level UCL corresponds to a difference between a second aggregate front power level request and a power discharge threshold.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the second power level command of the second hybrid-electric powertrain comprises limiting the second power level command by the second power level UCL.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the second power level UCL comprises: a second available discharge power capacity is determined at least in part by subtracting (i) a second aggregate front side power level request from (ii) a power discharge threshold, the second aggregate front side power level request comprising a second requested power level of one or more second front side hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level for discharging from the energy storage system.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the second power level UCL comprises: a second allocated discharge power capacity is determined, the second allocated discharge power capacity including a second allocation of a power discharge threshold for a second hybrid electric powertrain.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the second method comprises: the second power level UCL is set to the greater of (i) the available discharge power capacity and (ii) the second allocated discharge power capacity.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein the second power level LCL corresponds to a difference between a second aggregate front power level request and a charge threshold.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the second power level command of the second hybrid-electric powertrain comprises limiting the second power level command by the second power level LCL.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the second power level LCL comprises: a second available storage power capacity is determined at least in part by subtracting (i) a second aggregate front power level request from (ii) a charging threshold, the charging threshold comprising a threshold level for supplying electrical power to the energy storage system.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the second power level LCL comprises: a second allocated storage power capacity is determined, the second allocated storage power capacity comprising a second allocation of a charge threshold for a second hybrid electric powertrain.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the second method comprises: the second power level LCL is set to the smaller of (i) the available storage power capacity and (ii) the second allocated storage power capacity.

The hybrid-electric or all-electric propulsion system of any preceding clause, wherein determining the second power level command for the second hybrid-electric powertrain includes limiting the second power level command by the second power level UCL and the second power level LCL.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the first hybrid electric powertrain comprises: the first internal combustion engine, and/or wherein the second hybrid electric powertrain comprises: a second internal combustion engine.

The hybrid electric or all-electric propulsion system of any preceding clause, wherein the hybrid electric or all-electric propulsion system comprises the hybrid electric powertrain of any preceding clause.

A method of controlling a hybrid electric or all-electric powertrain of an aircraft, the method comprising: determining a capacity level of a hybrid electric powertrain electrically coupled to an energy storage system; and determining a control command for the hybrid electric powertrain, the control command determined based at least in part on the capacity level; wherein the capacity level is determined based at least in part on a selection between available capacity and allocated capacity; and wherein determining the control command for the hybrid electric powertrain includes limiting the control command by a capacity level.

The method of any preceding claim, wherein the available capacity is determined based at least in part on an aggregate front power level request.

The method of any preceding clause, wherein the allocation capacity is determined based at least in part on an allocation factor.

The method of any preceding claim, wherein the allocation capacity is determined based at least in part on a product of an allocation factor and a power discharge threshold or a charge threshold.

A method of controlling a hybrid electric or all-electric powertrain of an aircraft, the method comprising: determining an upper power level control limit (power level UCL) of a hybrid electric powertrain electrically coupled to an energy storage system; and determining a power level command for the hybrid electric powertrain, the power level command determined based at least in part on the power level UCL; wherein the power level UCL corresponds to a difference between an aggregate front power level request and a power discharge threshold; and wherein determining the power level command for the hybrid electric powertrain includes limiting the power level command by the power level UCL.

The method of any preceding clause, wherein determining the power level UCL comprises: determining an available discharge power capacity comprising a difference resulting from subtracting (i) an aggregate front power level request from (ii) a power discharge threshold, the aggregate front power level request comprising a requested power level of one or more front hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level of discharge from the energy storage system; and setting the power level UCL equal to the available discharge power capacity.

The method of any preceding clause, wherein limiting the power level command by the power level UCL comprises: the power level command is set equal to the power level UCL when the power level request of the hybrid electric powertrain is greater than the power level UCL.

The method of any preceding clause, wherein limiting the power level command by the power level UCL comprises: the power level command is set equal to the power level request when the power level request is between the power level UCL and a power level LCL, and the power level command is set equal to the power level LCL when the power level request is less than the power level LCL.

The method of any preceding clause, comprising: a request for a power level of a hybrid electric powertrain is received at an electronic controller that is incorporated into and/or communicatively coupled with a power control unit of the hybrid electric powertrain.

The method of any preceding clause, comprising: the aggregate front side power level request and/or the requested power levels of the one or more front side hybrid electric powertrains are received at the electronic controller.

The method of any preceding clause, comprising: the power level command is provided to one or more power management devices that define at least a portion of the power control unit of the hybrid electric powertrain.

The method of any preceding clause, wherein determining the power level UCL comprises: determining an allocated discharge power capacity, the allocated discharge power capacity comprising an allocation of the power discharge threshold for the hybrid electric powertrain; wherein setting the power level UCL equal to the available discharge power capacity comprises: setting the power level UCL equal to (i) the available discharge power capacity or (ii) the allocated discharge power capacity.

The method of any preceding clause, comprising: the power level UCL is set equal to (i) the available discharge power capacity or (ii) the allocated discharge power capacity using a capacity level operator.

The method of any preceding clause, wherein determining the power level UCL comprises: determining an available discharge power capacity, the available discharge power capacity comprising an allocation of the power discharge threshold to the hybrid electric powertrain; wherein setting the power level UCL equal to the available discharge power capacity comprises: the power level UCL is set equal to the greater of (i) the available discharge power capacity and (ii) the allocated discharge power capacity.

The method of any preceding claim, wherein the assigning of the power discharge threshold to the hybrid electric powertrain comprises applying an assignment factor to a power discharge threshold.

The method of any preceding claim, wherein the allocation of the power discharge threshold to the hybrid electric powertrain comprises a product of (i) an allocation factor and (ii) a power discharge threshold.

The method of any preceding claim, wherein the split factor comprises an inverse of a total number of the one or more front face hybrid electric powertrains.

The method of any preceding clause, comprising: determining a lower power level control limit (power level LCL) of the hybrid electric powertrain, wherein determining the power level LCL includes: determining an available storage power capacity comprising a difference resulting from subtracting (i) the aggregate front power level request from (ii) a charging threshold comprising a threshold level for supplying electrical power to the energy storage system, and setting the power level LCL equal to the available storage power capacity; wherein determining the power level command for the hybrid electric powertrain includes limiting the power level command by the power level LCL.

The method of any preceding clause, wherein determining the upper power level control limit comprises: determining an allocated storage power capacity, the allocated storage power capacity comprising an allocation of the charge threshold for the hybrid electric powertrain; wherein setting the power level LCL equal to the available storage power capacity comprises: setting the power level LCL equal to (i) the available storage power capacity or (ii) the allocated storage power capacity.

The method of any preceding clause, comprising: the power level LCL is set equal to (i) the available storage power capacity or (ii) the allocated storage power capacity using a capacity level operator.

The method of any preceding clause, wherein determining the upper power level control limit comprises: determining an allocated storage power capacity, the allocated storage power capacity comprising an allocation of the charge threshold for the hybrid electric powertrain; wherein setting the power level LCL equal to the available storage power capacity comprises: the power level LCL is set equal to the smaller of (i) the available storage power capacity and (ii) the allocated storage power capacity.

The method of any preceding claim, wherein the allocation of the charge threshold to a hybrid electric powertrain comprises a product of (i) an allocation factor and (ii) a charge threshold.

The method of any preceding clause, comprising: determining a power level LCL of the hybrid electric powertrain, wherein determining the power level LCL comprises: determining an available storage power capacity comprising a difference resulting from subtracting (i) an aggregate front power level request from (ii) a charging threshold comprising a threshold level for supplying electrical power to the energy storage system, and setting the power level LCL equal to the available storage power capacity; wherein determining the power level command for the hybrid electric powertrain includes limiting the power level command by the power level LCL.

The method of any preceding claim, wherein the allocation of the charge threshold to the hybrid electric powertrain comprises a product of (i) an allocation factor and (ii) a charge threshold.

A method of controlling a hybrid electric or all-electric propulsion system of an aircraft, the method comprising: determining a first power level UCL and a first power level LCL of a first hybrid electric powertrain, the first hybrid electric powertrain electrically coupled to an energy storage system; and determining a first power level command for the first hybrid electric powertrain, the first power level command determined based at least in part on the first power level UCL and the first power level LCL; wherein determining the first power level UCL comprises: determining a first available discharge power capacity at least in part by subtracting (i) a first aggregate front side power level request from (ii) a power discharge threshold, the first aggregate front side power level request comprising a first requested power level of one or more first front side hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level for discharging from the energy storage system, and setting a first power level UCL equal to the available discharge power capacity; wherein determining the first power level LCL comprises: determining a first available storage power capacity at least in part by subtracting (i) the first aggregate front power level request from (ii) the charge threshold, the charge threshold comprising a threshold level for supplying electrical power to the energy storage system, and setting a first power level LCL equal to the available storage power capacity; wherein determining the first power level command for the first hybrid electric powertrain includes limiting the first power level command by the first power level UCL and the first power level LCL.

The method of any preceding clause, wherein: determining the first power level UCL includes: determining a first allocated discharge power capacity, the first allocated discharge capacity including a first allocation of a power discharge threshold for the first hybrid electric powertrain, and setting the first power level UCL equal to the available discharge power capacity includes: setting the first power level UCL equal to the greater of (i) the available discharge power capacity and (ii) the first allocated discharge power capacity; and/or determining the first power level LCL comprises: determining a first allocated storage power capacity comprising a first allocation of the charge threshold for the first hybrid electric powertrain, and setting a first power level LCL equal to a first available storage power capacity comprises: the first power level LCL is set equal to the smaller of (i) the available storage power capacity and (ii) the first allocated storage power capacity.

The method of any preceding clause, comprising: determining a second power level UCL and a second power level LCL of a second hybrid electric powertrain electrically coupled to the energy storage system; and determining a second power level command for the second hybrid electric powertrain, the second power level command determined based at least in part on the second power level UCL and the second power level LCL; wherein determining the second power level UCL comprises: determining a second available discharge power capacity at least in part by subtracting (i) a second aggregate front side power level request from (ii) a power discharge threshold, the second aggregate front side power level request comprising a second requested power level of one or more second front side hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level for discharging from the energy storage system, and setting a second power level UCL equal to the available discharge power capacity; wherein determining the second power level LCL comprises: determining a second available storage power capacity at least in part by subtracting (i) a second aggregate front power level request from (ii) a charging threshold, the charging threshold comprising a threshold level for supplying electrical power to the energy storage system, and setting the second power level LCL equal to the available storage power capacity; wherein determining the second power level command for the second hybrid electric powertrain includes limiting the second power level command by the second power level UCL and the second power level LCL.

The method of any preceding clause, wherein: determining the second power level UCL includes: determining a second split discharge power capacity comprising a second split to a power discharge threshold of a second hybrid electric powertrain, and setting the second power level UCL equal to the available discharge power capacity comprises: setting the first power level UCI equal to the greater of (i) the available discharge power capacity and (ii) the second allocated discharge power capacity; and/or determining the second power level LCL comprises: determining a second allocated storage power capacity that includes a second allocation of a charge threshold for a second hybrid electric powertrain, and setting a second power level LCL equal to a second available storage power capacity includes: the second power level LCL is set equal to the smaller of (i) the available storage power capacity and (ii) the second allocated storage power capacity.

The method of any preceding clause, wherein: the one or more first front side hybrid electric powertrain includes a second hybrid electric powertrain, and wherein the first requested power level is for the second hybrid electric powertrain; and/or the one or more second front side hybrid electric powertrains includes the first hybrid electric powertrain, and wherein the second requested power level is for the first hybrid electric powertrain.

The method of any preceding clause, wherein: limiting the first power level command by the first power level UCL and the first power level LCL includes: setting a first power level command equal to a first power level requirement of the first hybrid electric powertrain when the first power level request is between the first power level UCL and the first power level LCL; and/or limiting the second power level command by the second power level UCL and the second power level LCL includes: the second power level command is set equal to the second power level request of the second hybrid electric powertrain when the second power level request is between the second power level UCL and the second power level LCL.

The method of any preceding clause, wherein: limiting the first power level command by the first power level UCL and the first power level LCL includes: setting the first power level command equal to the first power level UCL when the first power level request is greater than the first power level UCL, and setting the first power level command equal to the first power level LCL when the first power level request is less than the first power level LCL; and/or limiting the second power level command by the second power level UCL and the second power level LCL includes: the second power level command is set equal to the second power level UCL when the second power level request is greater than the second power level UCL, and the second power level command is set equal to the second power level LCL when the second power level request is less than the second power level LCL.

The method of any preceding clause, comprising: receiving at a first electronic controller (i) a first power level request for a first hybrid electric powertrain, and (ii) a first aggregate front power level request and/or a first requested power level for one or more first front hybrid electric powertrains, the first electronic controller being incorporated into a first power control unit for the first hybrid electric powertrains and/or communicatively coupled with the first power control device; and/or receiving at a second electronic controller (i) a second power level request for a second hybrid electric powertrain, and (ii) a second aggregate front power level request and/or a second requested power level for one or more second front hybrid electric powertrains, the second electronic controller being incorporated into and/or communicatively coupled with a second power control unit for the second hybrid electric powertrains.

The method of any preceding clause, comprising: providing a first power level command to one or more first power management devices defining at least a portion of a first power control unit for a first hybrid electric powertrain; and/or providing a second power level command to one or more second power management devices defining at least a portion of a second power control unit for a second hybrid electric powertrain.

The method of any preceding clause, wherein the method comprises: generating electrical power and/or converting electrical power to mechanical power with the first hybrid electric powertrain based at least in part on the first power level command to the one or more first power management devices; and/or generating electrical power and/or converting electrical power to mechanical power with the second hybrid electric powertrain based at least in part on the second power level command to the one or more second power management devices.

The method of any preceding clause, wherein the method comprises: generating mechanical power with the first hybrid electric powertrain and providing the mechanical power to the one or more first propellers based at least in part on a first power level command to the one or more first power management devices; and/or generating mechanical power with the second hybrid electric powertrain based at least in part on the second power level command to the one or more second power management devices and providing the mechanical power to one or more second propellers.

The method of any preceding clause, wherein the method comprises: providing electrical power from the first hybrid electric powertrain to the energy storage system based at least in part on a first power level command to the one or more first power management devices; and/or providing electrical power from the second hybrid electric powertrain to the energy storage system based at least in part on a second power level command to the one or more second power management devices.

The method of any preceding clause, wherein the method comprises: receiving electrical power from the energy storage system at the first hybrid electric powertrain based at least in part on a first power level command to the one or more first power management devices; and/or receiving electrical power from the energy storage system at the second hybrid electric powertrain based at least in part on a second power level command to the one or more second power management devices.

The method of any preceding clause, wherein the method comprises: receiving electrical power from the second hybrid electric powertrain at the first hybrid electric powertrain based at least in part on the first power level command to the one or more first power management devices; and/or receiving electrical power from the first hybrid electric powertrain at the second hybrid electric powertrain based at least in part on a second power level command to the one or more second power management devices.

The method of any preceding clause, wherein: the first hybrid electric powertrain includes: a first internal combustion engine, a first electric machine, one or more first propellers, and the first power control unit, wherein the one or more first propellers are mechanically coupled with the first electric machine and/or the first internal combustion engine, wherein the first power control unit is electrically coupled with the first electric machine; and/or the second hybrid electric powertrain comprises: a second internal combustion engine, a second electric machine, one or more first propellers, and a second power control unit, wherein the one or more second propellers are mechanically coupled to the second electric machine and/or the second internal combustion engine, wherein the second power control unit is electrically coupled to the second electric machine.

A method of controlling a hybrid electric or all-electric propulsion system according to any preceding clause, wherein the method comprises the method of controlling a hybrid electric powertrain in any preceding clause.

The method of any preceding clause, wherein the method is performed using the hybrid or all-electric propulsion system and/or hybrid electric powertrain of any preceding clause.

A non-transitory computer-readable medium comprising computer-executable instructions that, when executed by a processor associated with an electronic controller for a hybrid electric or all-electric powertrain of an aircraft, cause the electronic controller to perform a method comprising: determining an upper power level control limit (power level UCL) of a hybrid electric powertrain electrically coupled to an energy storage system; and determining a power level command for the hybrid electric powertrain, the power level command determined based at least in part on the power level UCL; wherein the power level UCL corresponds to a difference between an aggregate front power level request and a power discharge threshold; and wherein determining the power level command for the hybrid electric powertrain includes limiting the power level command by the power level UCL.

A non-transitory computer-readable medium comprising computer-executable instructions that, when executed by a processor associated with an electronic controller for a hybrid electric powertrain of an aircraft, cause the electronic controller to perform the method of any preceding clause.

This written description uses examples to describe the presently disclosed subject matter, including the best mode, and to enable any person skilled in the art to practice such subject matter, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the presently disclosed subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. The scope of the claims includes such other examples that include structural elements that do not differ from or are not substantially different from the literal language of the claims.

Claims

1. A hybrid electric or all-electric powertrain for an aircraft, the powertrain comprising:

a motor;

an energy storage system; and

a power control unit electrically coupling the electric machine to the energy storage system;

Wherein the power control unit comprises an electronic controller comprising a non-transitory computer-readable medium including computer-executable instructions, wherein the computer-executable instructions, when executed by a processor associated with the electronic controller, cause the power control unit to perform a method comprising:

determining an upper power level control limit (power level UCL) of the power control unit, wherein the power level UCL corresponds to a difference between an aggregate front power level request and a power discharge threshold; and

determining a power level command for the power control unit, the power level command determined based at least in part on the power level UCL, wherein determining the power level command for the power control unit includes limiting the power level command by the power level UCL.

2. The hybrid electric or all-electric powertrain of claim 1, wherein determining the power level UCL comprises:

determining an available discharge power capacity comprising a difference resulting from subtracting (i) the aggregate front side power level request from (ii) the power discharge threshold, the aggregate front side power level request comprising a requested power level of one or more front side hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level of discharge from the energy storage system; and

The power level UCL is set equal to the available discharge power capacity.

3. The hybrid or all-electric powertrain of claim 2, wherein the hybrid electric powertrain, the one or more front side hybrid electric powertrains, and the energy storage system are electrically coupled to a power distribution bus.

4. The hybrid or all-electric powertrain of claim 2, wherein the requested power level of the one or more front-side hybrid electric powertrains is provided by an input device comprising at least one of: a thrust lever, a power lever, or an automatic throttle system.

5. The hybrid electric or all-electric powertrain of claim 1, wherein the hybrid electric powertrain comprises a series configuration, a parallel configuration, or a series-parallel configuration.

6. The hybrid electric or all-electric powertrain of claim 1, comprising:

an internal combustion engine; and

one or more propellers configured to receive mechanical power from the internal combustion engine and the electric machine, either alone or simultaneously.

7. The hybrid electric or all-electric powertrain of claim 1, wherein the power control unit comprises one or more power management devices comprising at least one of: an inverter, a converter, a rectifier, a synchronous converter, a synchronous buck converter, a bi-directional interleaved converter, an autotransformer rectifier, or a matrix converter.

8. A method of controlling a hybrid electric or all-electric powertrain of an aircraft, the method comprising:

determining an upper power level control limit (power level UCL) of a hybrid electric powertrain electrically coupled to an energy storage system; and

determining a power level command for the hybrid electric powertrain, the power level command determined based at least in part on the power level UCL;

wherein the power level UCL corresponds to a difference between an aggregate front power level request and a power discharge threshold; and is also provided with

Wherein determining the power level command for the hybrid electric powertrain includes limiting the power level command by the power level UCL.

9. The method of claim 8, wherein limiting the power level command by the power level UCL comprises at least one of:

Setting the power level command equal to the power level UCL when the power level request of the hybrid electric powertrain is greater than the power level UCL; or (b)

The power level command is set equal to the power level request when the power level request is between the power level UCL and a lower power level control limit (power level LCL), and the power level command is set equal to the power level LCL when the power level request is less than the power level LCL.

10. The method of claim 8, wherein determining the power level UCL comprises:

determining an available discharge power capacity comprising a difference resulting from subtracting (i) an aggregate front power level request from (ii) a power discharge threshold, the aggregate front power level request comprising a requested power level of one or more front hybrid electric powertrains electrically coupled to the energy storage system, and the power discharge threshold comprising a threshold level of discharge from the energy storage system; and

the power level UCL is set equal to the available discharge power capacity.