CN212400925U

CN212400925U - Energy management system of extended-range hybrid power engineering machinery

Info

Publication number: CN212400925U
Application number: CN202021527871.6U
Authority: CN
Inventors: 易琅琳
Original assignee: Sichuan Dinghong Zhidian Equipment Technology Co ltd
Current assignee: Sichuan Dinghong Zhidian Equipment Technology Co ltd
Priority date: 2020-07-29
Filing date: 2020-07-29
Publication date: 2021-01-26
Anticipated expiration: 2030-07-29

Abstract

The embodiment of the application discloses an extended-range hybrid power engineering machinery energy management system, wherein a central controller in the system is used for respectively controlling the operation of a range extender, an energy management unit, a lithium battery system and a load; the range extender supplies power to the load according to the preset power, and in the power supply process, when the preset power is larger than the power required by the load, the range extender supplies power to the load and charges the lithium battery system; when the preset power of the range extender is smaller than the power required by the load, the lithium battery system and the range extender simultaneously supply power to the load; the energy management unit is used for controlling the on-off of circuits between the range extender, the load and the lithium battery system. According to the embodiment of the application, the range extender supplies power to the load according to the preset power, and most of the power output by the range extender is directly supplied to the load, so that energy conversion consumption in the charging and discharging processes of the energy storage system is avoided, and the energy efficiency of the range extender is greatly improved.

Description

Energy management system of extended-range hybrid power engineering machinery

Technical Field

The application relates to the technical field of engineering machinery, in particular to an extended range type hybrid engineering machinery energy management system.

Background

Engineering machinery is an important component of the equipment industry, and is necessary mechanical equipment for comprehensive mechanical construction engineering required by earth and stone construction engineering, pavement construction and maintenance, mobile hoisting, loading and unloading operation and various building engineering.

The traditional engineering machinery adopts a single energy driving mode, for example, a diesel internal combustion engine is adopted to drive the engineering machinery to work, or a novel pure electric driving mode is adopted to provide working energy for the engineering machinery. However, the diesel internal combustion engine has large consumption of energy, certain pollution to the environment and high cost; and the pure electric driving mode is not ideal for the engineering machinery needing to work for a long time because the power battery needs to be charged by frequently stopping working, and the endurance time and the endurance mileage are not ideal.

Based on the development of the technology, the extended-range hybrid engineering machinery comes up with the operation, and on the basis of pure electric drive, an internal combustion engine is additionally arranged to charge a power battery or directly drive a motor to increase the endurance mileage of the engineering machinery, so that the problem of short endurance mileage of the pure electric drive is solved. However, most of the conventional range-extended hybrid construction machines are powered by a power battery, and in a power battery power supply scheme, the output energy of a range extender is consumed and supplied to a load through the conversion of the power battery, so that the energy efficiency of the range extender is low.

SUMMERY OF THE UTILITY MODEL

The application provides an energy management system for a range-extended hybrid engineering machine, which aims to solve the problem that in the power battery power supply scheme of the range-extended hybrid engineering machine in the prior art, the output energy of a range extender is consumed to supply a load through the conversion of a power battery, the energy efficiency of the range extender is low, and the working energy efficiency of the range extender of the engineering machine is improved.

The application provides a hybrid engineering machinery energy management system of increase form, including central controller, increase journey ware, energy management unit and lithium battery system, energy management unit is used for connecting the load, load and central controller communication connection, wherein:

the central controller is used for respectively controlling the operation of the range extender, the energy management unit, the lithium battery system and the load;

the range extender supplies power to the load according to the preset power, and in the power supply process, when the preset power is larger than the power required by the load, the range extender supplies power to the load and charges the lithium battery system;

when the preset power is smaller than the power required by the load, the lithium battery system and the range extender simultaneously supply power to the load;

the energy management unit is used for controlling the on-off state of circuits between the range extender, the load and the lithium battery system when the range extender supplies power to the load and the lithium battery system charges or when the lithium battery system and the range extender supply power to the load, so as to complete power supply.

In one possible implementation manner of the present application, the lithium battery system is further configured to recover feedback energy generated by the load when the engineering machine is braked or decelerated.

In one possible implementation manner of the present application, when the electric quantity of the lithium battery system reaches a first preset electric quantity, the lithium battery system is configured to supply power to the load alone.

In one possible implementation manner of the present application, the lithium battery system is further configured to provide starting electric energy for the range extender when the range extender is started.

In this application a possible implementation, the system still includes super capacitor system and one-way device that switches on, and central controller still is used for controlling super capacitor system and one-way device that switches on respectively, and super capacitor system is connected with the energy management unit electricity, and super capacitor system is connected with lithium battery system electricity through one-way device that switches on, and the one-way direction that switches on the device is the direction from super capacitor system to lithium battery system, wherein:

when the preset power is larger than the power required by the load, the energy management unit simultaneously conducts a circuit between the range extender and the super capacitor and a circuit between the range extender and the load, so that the range extender supplies power to the load and simultaneously charges the super capacitor system, and after the electric quantity of the super capacitor system reaches a second preset electric quantity, the super capacitor system supplies the electric quantity which is more than the second preset electric quantity to the lithium battery system through the one-way conduction device;

when the preset power is smaller than the power required by the load, the energy management unit simultaneously conducts a circuit between the super capacitor system and the load and a circuit between the range extender and the load, so that the range extender and the super capacitor system simultaneously supply power to the load.

In one possible implementation manner of the present application, the system further includes a bidirectional voltage converter in communication connection with the central controller, the bidirectional voltage converter is electrically connected with the super capacitor system and the energy management unit respectively, wherein:

the bidirectional voltage converter is used for reducing the input voltage of the super capacitor system and boosting the output voltage of the super capacitor system.

In a possible implementation manner of the present application, the system further includes a charging device in communication connection with the central controller, the charging device is electrically connected to the lithium battery system, and when the lithium battery system is idle, the charging device is used for charging the lithium battery system.

In this application, increase journey ware includes the engine, generator and two-way AC/DC converter, the engine is connected with the generator machinery, the generator is connected with two-way AC/DC converter electricity, the engine is used for producing kinetic energy, the generator is used for converting the kinetic energy that the engine produced into the alternating current, or convert the alternating current into kinetic energy and drive the engine start, two-way AC/DC converter is used for converting the alternating current into direct current output and supplies power for load and lithium battery system, or convert the direct current of lithium battery system output into alternating current input, drive the engine start generator.

In the application, supply power for the load through making the range extender according to predetermineeing the power, when the required power of load is the same with the power of predetermineeing of range extender, the range extender independently supplies power for the load, energy conversion consumption among the energy storage system charge-discharge process has been avoided, the efficiency of range extender has been improved, when the load operating mode is unstable, when needing higher operating power, supply required power for the load through lithium battery system, when the required power of load is less than the preset power of range extender, provide lithium battery system with unnecessary power and charge, can make the range extender work in energy-efficient district steadily all the time, the work efficiency of range extender has been improved greatly.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an embodiment of an energy management system of an extended range hybrid construction machine according to an embodiment of the present disclosure;

FIG. 2 is a schematic structural diagram of another embodiment of an energy management system of an extended range hybrid construction machine provided in an embodiment of the present application;

fig. 3 is a schematic structural diagram of another embodiment of an energy management system of an extended range hybrid construction machine provided in an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be considered as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, the word "exemplary" is used to mean "serving as an example, instance, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is presented to enable any person skilled in the art to make and use the application. In the following description, details are set forth for the purpose of explanation. It will be apparent to one of ordinary skill in the art that the present application may be practiced without these specific details. In other instances, well-known structures and processes are not set forth in detail in order to avoid obscuring the description of the present application with unnecessary detail. Thus, the present application is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

The embodiment of the present application provides an energy management system for an extended range hybrid construction machine, which is described in detail below.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an embodiment of an extended range hybrid construction machine energy management system according to an embodiment of the present disclosure, where the extended range hybrid construction machine energy management system may include: the energy management system comprises a central controller 100, a range extender 200, an energy management unit 300 and a lithium battery system 400, wherein the energy management unit 300 is electrically connected with a load 500, and the load 500 is in communication connection with the central controller 100. .

Referring to fig. 1, the central controller 100, the range extender 200, the energy management unit 300, the lithium battery system 400 and the load 500 may be communicatively connected by any Communication method, including but not limited to a Serial Communication (Serial Communication) method, a Wireless Communication (Wireless Communication) method, and the like. The central controller 100 may implement data transmission and control with the range extender 200, the energy management unit 300, the lithium battery system 400, and the load 500 through the above-mentioned communication manner.

In this application embodiment, extend journey ware 200 can be including the engine, generator and the two-way alternating current-direct current converter that connect gradually, wherein, the engine is connected with generator machinery, the generator is connected with two-way alternating current-direct current converter electricity, the engine is used for producing kinetic energy, the generator is used for converting the kinetic energy that the engine produced into the alternating current, two-way alternating current-direct current converter is used for converting this alternating current into direct current output, be used for supplying power for lithium battery system 400 and load 500, also can be used for converting the direct current of lithium battery system 400 output into alternating current input, drive the engine.

In the embodiment of the present application, the engine may be a gasoline engine, a diesel engine, a Compressed Natural Gas (CNG) engine, a Liquefied Natural Gas (LNG) engine, and other common engines on the market at present, the generator may be different types of generators such as a synchronous generator, an asynchronous generator, a single-phase generator, and a three-phase generator, and the bidirectional ac/dc converter may be any type of Rectifier/Inverter (Inverter) that is currently available, and is not limited herein specifically.

The energy management Unit 300 in the embodiment of the present application may be a Power Distribution Unit (PDU) or other devices for realizing Power Distribution, and the lithium battery system in the embodiment of the present application may be replaced by a lead-acid battery system, a nickel-metal hydride battery system, or other battery systems.

The load 500 in the embodiment of the present application may be a motor, a compressor, a heater, or other devices that need to consume energy or generate feedback energy. The feedback energy specifically refers to electric energy which can be recovered and stored, and the electric energy can be converted from related mechanical energy such as potential energy and kinetic energy.

It can be understood by those skilled in the art that the schematic structural diagram shown in fig. 1 is only one structural diagram of the present application, and does not limit the present application, and other application scenarios may further include more energy storage systems than those shown in fig. 1, for example, only 1 lithium battery system is shown in fig. 1, and it can be understood that the extended range hybrid engineering machine energy management system may further include 2 or more other energy storage systems communicatively connected to the central controller 100 and electrically connected to the energy management unit 300, which is not limited herein.

It should be noted that the schematic structural diagram of the extended range hybrid construction machine energy management system shown in fig. 1 is only an example, and the extended range hybrid construction machine energy management system and the structure described in the embodiment of the present application are for more clearly illustrating the technical solutions of the embodiment of the present application, and do not constitute a limitation to the technical solutions provided in the embodiment of the present application.

First, an embodiment of the present application provides an extended range hybrid construction machine energy management system, as shown in fig. 1, the system includes a central controller 100, a range extender 200, an energy management unit 300, and a lithium battery system 400, the energy management unit 300 is used for connecting a load 500, where:

the central controller 100 is in communication connection with the range extender 200, the energy management unit 300, the lithium battery system 400 and the load 500, respectively, and is configured to control operations of the range extender 200, the energy management unit 300, the lithium battery system 400 and the load 500, respectively.

In the embodiment of the present application, the central controller 100 is respectively in communication with the range extender 200, the energy management unit 300, the lithium battery system 400 and the load 500, receives feedback information of the range extender 200, the energy management unit 300, the lithium battery system 400 and the load 500, and simultaneously sends a control instruction to the range extender 200, the energy management unit 300, the lithium battery system 400 and the load 500 to instruct operations of the range extender 200, the energy management unit 300, the lithium battery system 400 and the load 500. It should be noted that the central controller 100 may be a device having a control function, or may be composed of different controllers, for example, one controller may be respectively configured for the range extender 200, the energy management unit 300, the lithium battery system 400, and the load 500 to control the range extender 200, the energy management unit 300, the lithium battery system 400, and the load 500, and the central controller 100 of this embodiment further has functions of fault judgment, distribution policy adjustment, real-time monitoring, and the like, and specific functions of the central controller 100 may be selectively adjusted according to actual application scenarios.

The range extender 200 supplies power to the load 500 according to the preset power, and in the power supply process, when the preset power is larger than the power required by the load 500, the range extender 200 supplies power to the load 500 and charges the lithium battery system 400.

In the embodiment of the present application, the preset power of the range extender 200 is set in the efficient energy-saving region of the range extender 200, so that the range extender 200 stably outputs with the lowest energy consumption and the highest efficiency to provide the working electric energy for the load 500, when the preset power of the range extender 200 is the same as the power required by the load 500, the range extender 200 independently supplies power to the load 500, and because the working environment of the engineering machinery is complex, the power required by the load 500 is not at a constant value, when the preset power output by the range extender 200 is greater than the power required by the load 500, the range extender 200 supplies the excess power, that is, the power not required by the load 500, to the lithium battery system 400, and charges the lithium battery system 400.

When the preset power of the range extender 200 is smaller than the power required by the load 500, the lithium battery system 400 and the range extender 200 simultaneously supply power to the load 500.

As above, in the embodiment of the present application, the preset power of the range extender 200 is set in the efficient energy-saving region of the range extender 200, so that the range extender 200 stably outputs with the lowest energy consumption and the highest efficiency to provide the working electric energy for the load 500, and since the working environment of the engineering machinery is complex, the power required by the load 500 is not at a constant value, when the preset power output by the range extender 200 is smaller than the power required by the load 500, the lithium battery system 400 supplies the load 500 with insufficient power while the range extender 200 supplies power to the load 500, so as to ensure the normal operation of the load 500.

The energy management unit 300 is configured to control the on-off state of the circuit between the range extender 200, the load 500, and the lithium battery system 400 in the process of supplying power to the load 500 by the range extender 200 at the same time or in the process of supplying power to the load 500 by the lithium battery system 400 and the range extender 200 at the same time, so as to complete power supply.

In the embodiment of the present application, the energy management unit 300 includes a first switch K1 and a second switch K2, the range extender 200 is connected with the load 500 through a first switch K1, the lithium battery system 400 is connected with the load 500 through a second switch K2, the range extender 200 is connected with the lithium battery system 400 through a first switch K1 and a second switch K2, the energy management unit 300 controls the on-off state of the circuit between the range extender 200, the load 500 and the lithium battery system 400, specifically:

when the preset power of the range extender 200 is exactly equal to the power required by the load 500, the first switch K1 of the energy management unit 300 is closed, the circuit between the range extender 200 and the load 500 is conducted, and the second switch K2 opens the circuit between the lithium battery system 400 and the load 500, so that the range extender 200 independently supplies power to the load 500; when the working condition of the load 500 changes and the preset power of the range extender 200 is greater than the power required by the load 500, the second switch K2 of the energy management unit is closed, and a circuit between the range extender 200 and the lithium battery system 400 is switched on through the first switch K1 and the second switch K2, so that the range extender 200 supplies power to the load 500 and outputs redundant power to the lithium battery system 400 to charge the lithium battery system 400; when the working condition of the load 500 changes and the preset power of the range extender 200 is smaller than the power required by the load 500, the second switch K2 of the energy management unit is also closed, and a circuit between the lithium battery system 400 and the load 500 is conducted, so that the lithium battery system 400 supplies power to the load 500 while the range extender 200 supplies power to the load 500, and the power insufficient by the load 500 is supplemented.

In the embodiment of the application, the range extender 200 supplies power to the load 500 according to the preset power, when the power required by the load 500 is the same as the preset power of the range extender 200, the range extender 200 independently supplies power to the load 500, energy conversion consumption in the charging and discharging process of the energy storage system is avoided, the energy efficiency of the range extender 200 is improved, when the working condition of the load 500 is unstable and higher working power is required, the required power is supplemented to the load 500 through the lithium battery system 400, when the power required by the load 500 is smaller than the preset power of the range extender 200, the redundant power is supplied to the lithium battery system 400 for charging, the range extender 200 can always work in a high-efficiency energy-saving area, and the working energy efficiency of the range extender 200 is greatly improved.

In some embodiments of the present application, the lithium battery system 400 is also used to recover the feedback energy generated by the load 500 when the engineering machine is braked or decelerated.

In the embodiment of the present application, in the process that the range extender 200 supplies power to the load 500, when the engineering machinery brakes or decelerates, the load 500 generates a back electromotive force, so as to generate feedback energy, the feedback energy of the load 500 is recovered to the lithium battery system 400 through the second switch K2, and at this time, the power output by the range extender 200 is also supplied to the lithium battery system 400 through the first switch K1 and the second switch K2.

In some embodiments of the present application, the lithium battery system 400 is configured to separately supply power to the load 500 when the power of the lithium battery system 400 reaches a first preset power.

In this embodiment, the first preset electric quantity of the lithium battery system 400 is set to be a full electric quantity, that is, the electric quantity percentage is 100%, when the electric quantity percentage of the lithium battery system 400 reaches 100%, that is, when the lithium battery system is fully charged, the first switch K1 of the energy management unit 300 disconnects the circuit between the range extender 200 and the load 500, so that the range extender 200 stops supplying power to the load 500, or the range extender 200 stops supplying power to the load 500, and at this time, the lithium battery system 400 independently supplies working electric energy to the load 500 through the closed second switch K2. When the power of the lithium battery system 400 is reduced to a preset minimum power, for example, 10%, the range extender 200 is restarted to supply power to the load 500 through the first switch K1, and the process is repeated. It should be noted that the first preset electric quantity and the preset minimum electric quantity of the lithium battery system 400 may be set according to the performance or the application scenario of the lithium battery system, which is provided in this embodiment as an example only, and the specific numerical value is not limited here.

In some embodiments of the present application, the lithium battery system 400 is further configured to provide starting power for the range extender 200 when the range extender 200 is started, so that the range extender 200 can quickly reach the energy-efficient region to operate.

In the embodiment of the application, when the range extender 200 is started, the first switch K1 and the second switch K2 of the energy management unit 300 are closed, the lithium battery system 400 supplies power to the generator through the bidirectional ac/dc converter, so that the generator serves as a starting motor to drive the engine to reach a required rotating speed in a short time, and the range extender 200 starts to supply power to the load 500 at a high energy consumption stage when the range extender 200 is started, thereby saving energy.

In some embodiments of the present application, the energy management system of the extended-range hybrid engineering machinery further includes a charging device 900 in communication connection with the central controller 100, the charging device 900 is electrically connected to the lithium battery system 400, the charging device 900 in this embodiment may be an external commercial power charging pile, a mobile charging device, or another energy storage device, the charging device 900 may alternately charge the lithium battery system 400 with the extended-range device 200, or independently charge the lithium battery system 400, or charge the lithium battery system 400 when the extended-range device 200 fails, or when the lithium battery system 400 is idle.

As shown in fig. 2, in some embodiments of the present application, the energy management system of the extended range hybrid construction machine further includes a super capacitor system 600 and a unidirectional conducting device 700, the central controller 100 is further configured to control the super capacitor system 600 and the unidirectional conducting device 700 respectively, the super capacitor system 600 is electrically connected to the energy management unit 300, the super capacitor system 600 is electrically connected to the lithium battery system 400 through the unidirectional conducting device 700, and a unidirectional conducting direction of the unidirectional conducting device 700 is a direction from the super capacitor system 600 to the lithium battery system 400, where:

when the preset power of the range extender 200 is greater than the power required by the load 500, the energy management unit 300 simultaneously conducts the circuit between the range extender 200 and the supercapacitor 600 and the circuit between the range extender 200 and the load 500, so that the range extender 200 simultaneously supplies power to the load 500 and the supercapacitor system 600, and when the electric quantity of the supercapacitor system 600 reaches a second preset electric quantity, the supercapacitor system 600 supplies the electric quantity greater than the second preset electric quantity to the lithium battery system 400 through the one-way conduction device 700 for charging;

when the preset power is smaller than the power required by the load 500, the energy management unit 300 simultaneously turns on the circuit between the super capacitor system 600 and the load 500 and the circuit between the range extender 200 and the load 500, so that the range extender 200 and the super capacitor system 600 simultaneously supply power to the load 500.

In this embodiment, the energy management unit 300 further includes a third switch K3, the super capacitor system 600 is electrically connected to the load 500 through the third switch K3, and when the preset power of the range extender 200 is greater than the power required by the load 500 during the process of supplying power to the load 500 by the range extender 200, the third switch K3 of the energy management unit 300 is closed, so as to open the circuit between the super capacitor system 600 and the range extender 200, and the extra electric energy is stored in the super capacitor system 600 through the third switch K3. The second preset electric quantity of the super capacitor system 600 is set to be full electric quantity, that is, the electric quantity percentage is 100%, and when the electric quantity percentage of the super capacitor system 600 reaches 100%, the excessive electric quantity is supplied to the lithium battery system 400 through the one-way conduction device 700 to charge the lithium battery system 400.

When the preset power of the range extender 200 is smaller than the power required by the load 500, the third switch K3 of the energy management unit 300 is also closed, the circuit between the super capacitor system 600 and the load 500 is turned on, so that the load 500 is simultaneously supplied with the range extender 200 and the super capacitor system 600, and if the sum of the powers provided by the super capacitor system 600 and the range extender 200 is still smaller than the power required by the load 500, the second switch K2 of the energy management unit 300 is closed, the circuit between the lithium battery system 400 and the load 500 is turned on, so that the lithium battery system 400, the super capacitor system 600 and the range extender 200 simultaneously supply power to the load 500.

It should be noted that the second preset amount of power in this embodiment may be set according to the voltage difference of the unidirectional conducting device 700. The setting may also be performed according to the performance or application scenario of the super capacitor system, which is provided in this embodiment as an example only, and the specific value is not limited here. The unidirectional conducting device 700 in this embodiment may be a unidirectional voltage (DC-DC) converter, a high-power diode, or a unidirectional Current transmission device capable of realizing Current boosting/voltage reduction. Due to the existence of the unidirectional flux device 700, the electric energy can only flow from the super capacitor system 600 to the lithium battery system 400, and cannot flow in the reverse direction.

Because the cycle number of a life cycle of the lithium battery is limited, and the cycle number of the super capacitor can reach 100 ten thousand, the super capacitor has the advantages of high power and long cycle life, the super capacitor system 600 can replace the peak clipping and valley filling functions of the lithium battery system 400, the lithium battery system 400 is prevented from being charged and discharged frequently, the service life of the lithium battery system 400 is prolonged, and the super capacitor has better low-temperature performance than the lithium battery and can provide enough power when being started at low temperature. The super capacitor system 600 in this embodiment may be obtained by connecting a plurality of super capacitor units in series and in parallel, or may be another high power energy storage system, such as a flywheel energy storage system, and the like, and other schemes that are the same as or similar to the principle of this embodiment also belong to the protection scope of this application, for example, the scheme of this embodiment may also be implemented by reasonably setting the parameters of the range extender 200, the super capacitor system 600, and the lithium battery system 400.

In this embodiment, the super capacitor system 600 is further configured to recover the feedback energy generated by the load 500 during braking or deceleration of the engineering machine, and similarly, when the electric quantity of the super capacitor system 600 reaches the second preset electric quantity, the excess feedback energy is also supplied to the lithium battery system 400 through the one-way conduction device 700 to charge the lithium battery system 400.

When the electric quantity of the lithium battery system 400 reaches the first preset electric quantity, that is, the lithium battery system 400 is fully charged, the first switch K1 of the energy management unit 300 disconnects the circuit between the range extender 200 and the load 500, or the range extender 200 stops operating, the third switch K3 disconnects the circuit between the super capacitor system 600 and the load 500, so that the range extender 200 and the super capacitor system 600 stop supplying power to the load 500, at this time, the second switch K2 of the energy management unit 300 is closed, the circuit between the lithium battery system 400 and the load 500 is conducted, and the lithium battery system 400 independently supplies working electric energy to the load 500.

In the embodiment of the application, when the range extender 200 fails, the first switch K1 of the energy management unit 300 is opened, the second switch K2 and the third switch K3 are closed, and the power supply system composed of the lithium battery system 400 and the super capacitor system 600 reasonably distributes electric quantity to provide working electric energy for the load 500 according to the power required by the load 500.

In the embodiment of the present application, in the process that the lithium battery system 400 independently supplies power to the load 500, when the engineering machine brakes or decelerates, the load 500 generates a back electromotive force, so as to generate feedback energy, and the feedback energy of the load 500 is recycled to the lithium battery system 400 through the second switch K2.

In the embodiment of the application, if the lithium battery system 400 and the super capacitor system 600 have a fault, the second switch K2 and the third switch K3 of the energy management unit 300 are opened, the first switch K1 is closed, and a circuit between the range extender 200 and the load 600 is conducted, so that the range extender 200 independently supplies power to the load 600; if the lithium battery system 400 has a fault, the second switch K2 of the energy management unit 300 is opened, the first switch K1 and the third switch K3 are closed, and a circuit between the range extender 200 and the load 600 and a circuit between the super capacitor system 600 and the load 500 are conducted, so that the range extender 200 and the super capacitor system 600 supply power to the load 600; if the super capacitor system 600 fails, the third switch K3 of the energy management unit 300 is opened, the first switch K1 and the second switch K2 are closed, and a circuit between the range extender 200 and the load 600 and a circuit between the lithium battery system 400 and the load 500 are conducted, so that the range extender 200 and the lithium battery system 400 supply power to the load 600.

As shown in fig. 3, in some embodiments of the present application, the extended range hybrid construction machine energy management system further includes a bidirectional voltage converter 800 communicatively connected to the central controller 100, the bidirectional voltage converter 800 being connected to the super capacitor system 400 and the energy management unit 300, respectively, wherein:

the bidirectional voltage converter 800 is used for stepping down the input voltage of the super capacitor system 800 and stepping up the output voltage of the super capacitor system 600.

In the embodiment of the present application, the super capacitor system 600 is formed by connecting a plurality of super capacitor units in series and in parallel, and the bidirectional voltage converter 800 may implement bidirectional BUCK-BOOST conversion, which may be a BUCK-BOOST circuit or a bidirectional BUCK-BOOST converter having a BOOST (BOOST)/BUCK (BUCK) circuit topology. In this embodiment, the unidirectional conducting device 700 may be a unidirectional voltage converter with a unidirectional boosting function, or may be a unidirectional Boosting (BOOST) circuit, and BOOSTs the voltage input from the super capacitor system 800 to the lithium battery system 400. The third switch K3 of the energy management unit 300 is electrically connected to the super capacitor system 600 through the bi-directional voltage converter 800, since the bi-directional voltage converter 800 can step down the voltage input to the super capacitor system 600 by the energy management unit 300, and the voltage output to the energy management unit 300 by the super capacitor system 600 is stepped up, the voltage of the super capacitor system 600 can be reduced, and the voltage of the whole extended range type hybrid power engineering machinery energy management system can be satisfied, the number of the super capacitors connected in series and parallel can be reduced, since the super capacitors are expensive, the cost of the super capacitor system 600 can be reduced, and the cost of the whole extended range type hybrid power engineering machinery energy management system can be further reduced.

It should be noted that, in the embodiment of the present application, the manner of controlling the on/off of the circuit through each switch of the energy management unit 300 is only one manner of implementing the present application, and other manners of controlling the circuit according to the same or similar principle that can implement the on/off of the circuit are also applicable to the embodiment of the present application. In addition, it should be understood by those skilled in the art that, in order to implement the embodiment of the present application, the amount of power of the lithium battery system 400 is sufficient to supply power to the load 500 together with the range extender 200, and specifically, the range extender 200 charges the lithium battery system 400 with a larger amount of power than the amount of power released by the lithium battery system 400 or charges the lithium battery system 400 through the charging device 900 when the amount of power of the lithium battery system 400 is insufficient, so as to ensure that the system operates normally.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and parts that are not described in detail in a certain embodiment may refer to the above detailed descriptions of other embodiments, and are not described herein again.

In a specific implementation, each unit or structure may be implemented as an independent entity, or may be combined arbitrarily to be implemented as one or several entities, and the specific implementation of each unit or structure may refer to the foregoing embodiments, which are not described herein again.

The above detailed description is provided for an energy management system of an extended range hybrid construction machine provided in the embodiments of the present application, and specific examples are applied herein to explain the principles and implementations of the present application, and the description of the above embodiments is only used to help understanding the present application; meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. An energy management system of a range-extended hybrid power engineering machine is characterized by comprising a central controller, a range extender, an energy management unit and a lithium battery system, wherein the energy management unit is used for connecting a load, and the load is in communication connection with the central controller, wherein:

the range extender supplies power to the load according to preset power, and in the power supply process, when the preset power is larger than the power required by the load, the range extender supplies power to the load and charges the lithium battery system;

the energy management unit is used for the increase journey ware does the load power supply is simultaneously for the in-process that lithium battery system charges, perhaps is in lithium battery system with the increase journey ware is simultaneously for the in-process of load power supply, control the increase journey ware the load with the break-make state of the circuit between two liang of lithium battery system to accomplish the power supply.

2. The system of claim 1, wherein the lithium battery system is further configured to recover regenerative energy from the load during braking or deceleration of the work machine.

3. The system of claim 1, wherein the lithium battery system is configured to individually power the load when the battery capacity of the lithium battery system reaches a first predetermined capacity.

4. The system of claim 1, wherein the lithium battery system is further configured to provide starting power to the range extender when the range extender is started.

5. The system of claim 1, further comprising a super capacitor system and a unidirectional conducting device, wherein the central controller is further configured to control the super capacitor system and the unidirectional conducting device, respectively, the super capacitor system is electrically connected to the energy management unit, the super capacitor system is electrically connected to the lithium battery system through the unidirectional conducting device, and a unidirectional conducting direction of the unidirectional conducting device is a direction from the super capacitor system to the lithium battery system, wherein:

when the preset power is larger than the power required by the load, the energy management unit simultaneously conducts a circuit between the range extender and the super capacitor and a circuit between the range extender and the load, so that the range extender supplies power to the load and simultaneously charges the super capacitor system, and after the electric quantity of the super capacitor system reaches a second preset electric quantity, the super capacitor system supplies the electric quantity which is more than the second preset electric quantity to the lithium battery system through the one-way conduction device for charging;

6. The system of claim 5, further comprising a bi-directional voltage converter communicatively coupled to the central controller, the bi-directional voltage converter being electrically coupled to the supercapacitor system and the energy management unit, respectively, wherein:

7. The system of claim 1, further comprising a charging device communicatively coupled to the central controller, the charging device being electrically coupled to the lithium battery system, the charging device being configured to charge the lithium battery system when the lithium battery system is idle.

8. The system of claim 1, wherein the range extender comprises an engine, a generator and a bidirectional ac/dc converter, the engine is mechanically connected to the generator, the generator is electrically connected to the bidirectional ac/dc converter, the engine is configured to generate kinetic energy, the generator is configured to convert the kinetic energy generated by the engine into ac power or ac power to drive the engine to start, the bidirectional ac/dc converter is configured to convert the ac power into dc power to supply power to the load and the lithium battery system, or convert the dc power output by the lithium battery system into ac power to drive the engine to start the generator.