EP4619630A1

EP4619630A1 - Electrically powered compressors for improved engine operability and serviceability

Info

Publication number: EP4619630A1
Application number: EP23892297.5A
Authority: EP
Inventors: Stephen Edward RODRIGUEZ; Scott Allen Rittenhouse; Brian S. BOWER
Original assignee: Cummins Inc
Current assignee: Cummins Inc
Priority date: 2022-11-16
Filing date: 2023-10-26
Publication date: 2025-09-24
Also published as: WO2024107533A1; CN120187944A

Abstract

A system includes an internal combustion engine including an intake and an exhaust. The intake includes an electric compressor. An electronic control system is configured to control the electric compressor in order to, for example, perform diagnostics, provide thermal management of the engine and/or aftertreatment system, and/or improve performance of a turbocharger compressor.

Description

ELECTRICALLY POWERED COMPRESSORS FOR IMPROVED ENGINE OPERABILITY AND SERVICEABILITY

CROSS-REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to, and the benefit of the filing date of, U.S. Provisional App. Ser. No. 63/383,960 filed on November 16, 2022, which is incorporated herein by reference.

TECHNICAL FIELD

[0002] The present application relates generally to internal combustion engine systems, and more particularly, but not exclusively, to electrically powered compressors for improved operation and serviceability of internal combustion engines and related components.

BACKGROUND

[0003] Internal combustion engines may utilize a compressor in the intake in order to compress the intake flow to the cylinders of the engine. For example, the compressor of a turbocharger or supercharger is used to improve engine efficiency by increasing the density of the intake flow to allow more power per engine cycle. The compressor typically draws in ambient air and compresses it before it enters into the intake manifold at increased pressure. Some systems utilize a compressor that is powered electrically. However, existing approaches suffer from a number of disadvantages, shortcomings, and unmet needs. There remains a significant need for the unique apparatuses, methods, systems, and techniques disclosed herein.

DISCLOSURE OF EXAMPLE EMBODIMENTS

[0004] For the purposes of clearly, concisely, and exactly describing example embodiments of the present disclosure, the manner, and process of making and using the same, and to enable the practice, making and use of the same, reference will now be made to certain example embodiments, including those illustrated in the figures, and specific language will be used to describe the same. It shall nevertheless be understood that no limitation of the scope of the invention is thereby created, and that the invention includes and protects such alterations, modifications, and further applications of the example embodiments as would occur to one skilled in the art.

SUMMARY OF THE DISCLOSURE

[0005] A number of embodiments relate to internal combustion engines that operate with an electric compressor. As used herein, an electric compressor is a compressor that includes an electrically powered motor so that the electric compressor can be operated independently of the exhaust flow produced by the engine. The electric compressor can powered solely by electric power, or by electric power and/or by exhaust flow via a shaft-connected turbine in the exhaust system. The electric compressor can be a stand-alone compressor in the intake system of the internal combustion engine, an electric compressor that is upstream of a turbocharger compressor, an electric compressor that is downstream of a turbocharger compressor, and/or an electrically assisted turbocharger compressor.

[0006] One embodiment of the present disclosure is a system and method for servicing and/or diagnosing the internal combustion engine with the electric compressor. Another embodiment is a system and method for improving performance and/or durability of a turbocharger compressor by utilizing the electric compressor. Another embodiment is a system and method for increasing a temperature of an aftertreatment system of the internal combustion engine by utilizing the electric compressor. Another embodiment is a system and method for thermally managing the intake air flow to the internal combustion engine by utilizing the electric compressor. A further embodiment is a system and method of controlling the intake air flow to the internal combustion engine to assist in engine braking or thermally managing the exhaust output from the internal combustion engine by utilizing the electric compressor. [0007] This summary is provided to introduce a selection of concepts that are further described below in the illustrative embodiments. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. l is a schematic block diagram of an internal combustion engine system with an internal combustion engine and an electric compressor.

[0009] FIG. 2 is a schematic block diagram of another embodiment internal combustion engine system with an internal combustion engine and an electric compressor.

[0010] FIG. 3 is a schematic block diagram of another embodiment internal combustion engine system with an internal combustion engine and an electric compressor.

[0011] FIG. 4 is a schematic block diagram of another embodiment internal combustion engine system with an internal combustion engine and an electric compressor.

[0012] FIG. 5 is a flow diagram of one embodiment of a method for utilizing an electric compressor according to the present disclosure.

[0013] FIG. 6 is a flow diagram of another embodiment of a method for utilizing an electric compressor according to the present disclosure.

[0014] FIG. 7 is a flow diagram of another embodiment of a method for utilizing an electric compressor according to the present disclosure.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

[0015] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, any alterations and further modifications in the illustrated embodiments, and any further applications of the principles of the invention as illustrated therein as would normally occur to one skilled in the art to which the invention relates are contemplated herein.

[0016] With the systems and methods such as those shown in FIGs. 1-7, control strategies for an internal combustion engine system 10 that includes an internal combustion engine 12 and an electric compressor 100, 100’ that may be implemented to improve engine serviceability, compressor performance and durability, engine performance, and/or thermal management of the aftertreatment components and/or the engine. In an embodiment, the electric compressor 100, 100’ can be employed for diagnostics while the internal combustion engine 12 is shut down, and/or to improve engine performance during engine 12 operation such as by providing throttling and/or boosting of intake flow.

[0017] Certain embodiments include a turbocharger compressor in addition to an electric compressor 100, 100’. The turbocharger compressor life span and/or durability can be improved through modulation of electric compressor 100, 100’ to avoid or minimize violation of the mechanical limits of the turbocharger compressor, such as may occur due to low and high cycle fatigue, low pressure differential conditions, compressor surge, compressor outlet temperature conditions, and rotor speed conditions.

[0018] In another embodiment, electric compressor 100, 100’ is controlled to increase a temperature of an aftertreatment system, to thermally manage the intake air flow to the internal combustion engine 12, and/or to thermally managing the exhaust output from the internal combustion engine 12. In another embodiment, electric compressor 100, 100’ is controlled so the intake air flow to the internal combustion engine 12 assists in engine braking.

[0019] With reference to FIG. 1, an internal combustion engine system 10 includes internal combustion engine 12 and electric compressor 100 illustrated in schematic form. Internal combustion engine 12 receives fuel from a fuel source (not shown) and is operable to combust the fuel in one or more cylinders 14 of engine 12. Any type of fuel is contemplated for system 10, including diesel fuel, gasoline, gaseous fuel, hydrogen fuel, and dual fuel arrangements. Internal combustion engine system 10 may provide output power to propel a vehicle and/or to provide output power in a stationary application, such as a generator or equipment.

[0020] Engine 12 is connected with an intake 16 for providing an intake flow to cylinders 14 of engine 12 and an exhaust 18 for output of exhaust gases in an exhaust flow. In the illustrated embodiment, the engine 12 is shown with four cylinders 14, but any number and arrangement of cylinders 14 is contemplated, and system 10 is not limited to the number and arrangement shown in FIG. 1. Each cylinder 14 includes a piston slidably disposed in a combustion chamber, at least one intake valve to admit intake flow, and at least one exhaust valve to release exhaust gases produced from combustion.

[0021] Cylinder(s) 14 are connected to the intake 16 to receive the intake flow. Cylinder(s) 14 are connected to exhaust 18 that receives exhaust flow from cylinder(s) 14. Exhaust 18 can be connected to intake 16 with a high pressure exhaust gas recirculation (EGR) system 20 and/or a low pressure EGR system (not shown.) EGR system 20 may include an EGR valve 21 and/or an EGR cooler (not shown) with an EGR cooler bypass. Exhaust 18 may also include a turbine 32 of a turbocharger 30, such as shown in FIGs. 2-3.

[0022] Intake 16 includes one or more inlet supply conduits 22 extending from electric compressor 100 to an intake manifold connected to cylinders 14, which distributes the intake flow to cylinder(s) 14 of engine 12. Intake 16 may include an intake throttle 38 in certain embodiments. In other embodiments, electric compressor 100 is controlled in a manner that allows intake throttle 38 to be eliminated, such as shown in FIGs. 3-4. Exhaust 18 includes an exhaust conduit 24 extending from an exhaust manifold to an aftertreatment system 26. A controllable exhaust valve 28 or other suitable exhaust flow control device can be provided in exhaust conduit 24.

[0023] Aftertreatment system 26 can be connected downstream of exhaust valve 28. The aftertreatment system 26 may include, for example, three way catalysts (TWC), oxidation devices (DOC), particulate removing devices (DPF, CDPF), constituent absorbers or reducers (SCR, AMOX, LNT), reductant systems, and other components if desired.

[0024] In certain embodiments, a turbocharger 30 is provided in addition to an electric compressor 100, as shown in FIGs. 2-3. Turbocharger 30 includes turbine 32 in exhaust 18, and a turbocharger compressor 34 in intake 16. Compressor 34 is connected to turbine 32 with a shaft 36 so that turbocharger compressor 34 is driven by exhaust flow. FIGs. 2-3 illustrate a single stage turbocharger system, but multi-stage turbochargers are not precluded.

[0025] Electric compressor 100 can be a stand-alone electric compressor, such as shown in FIGs. 1-3, that includes a compressor wheel 102 in a housing, and the compressor wheel 102 is powered by an electric motor 104. In FIG. 1, electric compressor 100 is the sole device operable to compress intake flow. In FIG. 2, electric compressor 100 is located upstream of turbocharger compressor 34 and is operable to provide a compressed intake flow to turbocharger compressor 34. In FIG. 3, electric compressor 100 is located downstream of turbocharger compressor 34 and is operable to receive a compressed intake flow from turbocharger compressor 34 when turbocharger compressor 34 is operating.

[0026] In other embodiments, electric compressor 100 is an electrically assisted turbocharger compressor, such as shown by electric compressor 100’ in FIG. 4. Electric motor 104 is selectively engaged to shaft 36 of turbocharger 30’ in order to assist or boost the operation of turbocharger compressor 34 and to rotate turbocharger compressor 34 independently of any exhaust flow. In an embodiment, electric motor 104 of electric compressor 100’ can be selectively engaged to shaft 36 with a connection 106, such as a clutch or any other suitable selectively engageable connection. In either embodiment, electric motor 104 can be powered from an electrical system (not shown) of the internal combustion engine system 10.

[0027] Turbocharger 30, 30’ may be any suitable turbocharger known in the art, including variable geometry turbine turbochargers and/or wastegated turbochargers. For example, a wastegate provides a controllable bypass around turbine 32. Turbocharger compressor 34 may also or alternatively include a bypass.

[0028] In operation of internal combustion engine system 10, fresh air is supplied to electric compressor 100, 100’. The fresh air flow can be fdtered, unfiltered, and/or conditioned in any known manner, either before or after mixing with EGR flow when provided. The intake flow is pressurized with electric compressor 100 and/or compressor 34 and then provided to cylinders 14.

[0029] In any embodiment, the electric compressor 100, 100’ is controlled by an electronic control system (ECS) 120 to control the operational status of electric compressor 100, 100’. Electric motor 104 responds to control commands from ECS 120 to selectively start and stop electric compressor 100, 100’ to drive compressor wheel 102 and/or turbo shaft 36 to provide a compression boost to the intake flow to engine 12 and/or to selectively pressurize selected parts of internal combustion engine system 10, such as for service or diagnostics.

[0030] Referring further to FIG. 1, internal combustion engine 12 includes one or more engine sensors 122 operably connected to ECS 120 to provide signals indicative of one or more of the engine operating parameters (speed, pressure, temperature, combustion parameters, crankshaft position, etc.). In addition, intake 16 may include one or more intake sensors 124 and exhaust 18 may include one or more exhaust sensors 126 to provide signals indicative of one or more intake parameters (pressure, temperature, flow rate, etc.) and one or more exhaust parameters (pressure, temperature, flow rate, etc.) ECS 120 preferably includes one or more programmable microprocessors or microcontrollers of a solid-state, integrated circuit type, and one or more non-transitory memory media configured to store instructions executable by the one or more microprocessors or microcontrollers.

[0031] ECS 120 is configured to implement and/or output control commands to control operation of the electric motor 104 either directly or to a controller of electric motor 104, such as discussed below with reference to FIGs. 5-7. The control commands can be, for example, on-off commands to start/stop electric motor 104, speed commands to control the compressor speed, and/or commands to selectively engage and disengage the connection 106 between electric motor 104 and shaft 36. It shall be appreciated that FIG. 1 depicts control relationships between the foregoing components conceptually and that various communications hardware and protocols may be utilized to implement, such as one or more controller area networks (CAN) or other communications components.

[0032] The ECS 120 can be implemented in any of a number of ways that combine or distribute the control function across one or more control units in various manners. The ECS 120 may execute operating logic that defines various control, management, and/or regulation functions. This operating logic may be in the form of dedicated hardware, such as a hardwired state machine, analog calculating machine, programming instructions, and/or a different form as would occur to those skilled in the art. The ECS 120 may be provided as a single component or a collection of operatively coupled components; and may be comprised of digital circuitry, analog circuitry, or a hybrid combination of both of these types. When of a multi-component form, the ECS 120 may have one or more components remotely located relative to the others in a distributed arrangement. The ECS 120 can include multiple processing units arranged to operate independently, in a pipeline processing arrangement, in a parallel processing arrangement, or the like. It shall be further appreciated that the ECS 120 and/or any of its constituent components may include one or more signal conditioners, modulators, demodulators, Arithmetic Logic Units (ALUs), Central Processing Units (CPUs), limiters, oscillators, control clocks, amplifiers, signal conditioners, filters, format converters, communication ports, clamps, delay devices, memory devices, Analog to Digital (A/D) converters, Digital to Analog (D/A) converters, and/or different circuitry or components as would occur to those skilled in the art to perform the desired communications.

[0033] Referring to FIG. 5, a method 500 is shown for servicing and or diagnosing one of more components of internal combustion engine system 10 using electric compressor 100, 100’. Method 500 includes an operation 502 to operate the electric compressor 100, 100’ without running or operating internal combustion engine 12. Method 500 includes an operation 504 to determine one or more pressure and/or flow conditions of internal combustion engine system 10 associated with the operation of electric compressor 100, 100’. Method 500 includes an operation 506 to diagnose one or more faults based on the one or more pressure and/or flow conditions created by operation of the electric compressor 100, 100’.

[0034] In an embodiment, method 500 is performed at a repair/maintenance facility for system 10, such as in a service bay, or to perform a self-diagnostic, while internal combustion engine 12 is disabled or not running. The method 500 can be performed in whole or in part with ECS 120 and/or a service computer (not shown) associated with the repair facility, vehicle owner, or fleet manager. At least a portion of the service computer may be integrated within the ECS 120, or may be external to internal combustion engine system 10 (e.g., a component of a vehicle diagnostic system at a maintenance/repair shop) and accessible by ECS 120 via a datalink (not shown).

[0035] Any of the electric compressor arrangements of FIGs. 1-4 can be utilized to pressure internal combustion engine system 10 in order to diagnose and locate faults associated with the loss of the boost pressure provided by electric compressor 100, 100’. In an embodiment, electric compressor 100, 100’ replaces or augments the pressurization of one or more parts of internal combustion engine system 10 with shop air, such as is typically used in leak down or bubble tests. The fault detection for the components pressurized by electric compressor 100, 100’ can then be detected using one or more known methods. [0036] In an embodiment method 500, the electric compressor 100, 100’ is used in conjunction with feedback control to identify a fault condition of internal combustion engine system 10. For example, in an embodiment the pressure condition associated with operation 504 is a target pressure condition downstream of the electric compressor 100, 100’. The target pressure condition is known based on a correlation of the pressure condition with the speed of the electric compressor 100, 100’. ECS 120 and/or service computer is configured to compare the target pressure condition to a measured pressure condition downstream of the electric compressor 100, 100’ . One or more fault conditions can then be diagnosed based on a comparison of the target pressure condition with the measured pressure condition.

[0037] In an embodiment, the target pressure condition is a boost pressure condition in the intake 16. Other embodiments contemplate using flow conditions or other pressure conditions, such as a pressure and/or flow condition in one or more cylinders 14, a pressure and/or flow condition in exhaust 18, and/or a pressure and/or flow condition in EGR system 20, for example. [0038] In another embodiment of method 500, the pressure condition is a target boost pressure to be produced by the electric compressor 100. 100’. ECS 120 and/or service computer is configured to control an output of the electric compressor 100, 100’ in response to the target boost pressure. ECS 120 is further configured to compare the output of the electric compressor 100, 100’ to an expected output for the compressor 100, 100’ based on the target boost pressure that is produced. ECS 120 and/or service computer is further configured to diagnose the one or more fault conditions based on a comparison of the expected output for the electric compressor 100, 100’ and an actual output for the electric compressor 100, 100’. For example, the ECS 120 can compare an expected duty cycle or wheel speed of electric compressor 100, 100’ to produce the target boost pressure to the actual duty cycle or wheel speed required to produce the target boost pressure.

[0039] In an embodiment, ECS 120 and/or the service computer is configured to actuate one of more actuators to isolate the intake 16, the exhaust 18, EGR system 20, and/or the one or more cylinders 14 to diagnose the location of the one or more fault conditions. The one or more actuators include an intake throttle 38, an exhaust valve 28, and/or an exhaust gas recirculation valve 21. The one or more fault conditions can indicate, for example, a plumbing leak, faulty pressure sensor, a leaky valve, or excessive blow-by leakage. [0040] Referring to FIG. 6, another embodiment method 600 is illustrated. Method 600 includes an operation 602 to operate internal combustion engine 12 with a turbocharger 30, 30’. Method 600 includes an operation 602 to determine a target condition associated with turbocharger 30. 30’. Method 600 includes an operation 604 to operate the electric compressor 100, 100’ in response to the target condition associated with turbocharger 30, 30’.

[0041] In an embodiment, method 600 includes modulating the assistance level provided by electric compressor 100, 100’ to compressor 34 in order to avoid areas where mechanical limits of the compressor 34 may be violated. In an embodiment, method 600 includes modulating electric compressor 100, 100’ to avoid operational limits for electric compressor 100, 100’ without the presence of an additional turbocharger compressor 34. In the embodiments of FIGs. 2-3, method 600 includes balancing the work between electric compressor 100 and turbocharger compressor 34 to avoid or limit encroachment upon operational limits. Various operational limits are contemplated, such as those associated with compressor side oil leakage due to low pressure differential across the compressor 34, 100; compressor outlet temperature; compressor surge margin; and high and low cycle fatigue.

[0042] In the embodiments of FIGs. 2-3, method 600 included controlling the electric compressor 100 to provide boosting and/or throttling of the intake air flow to manipulate the operating conditions of the turbocharger compressor 34 to avoid oil leaks due to low pressure differentials and increase the lifespan of the turbocharger compressor 34. In the embodiments of FIGs. 2-4, under low and high engine load conditions, method 600 includes modulating the electric compressor 100, 100’ to assist turbocharger compressor 34 to avoid low and high cycle fatigue of the turbocharger compressor 34. In an embodiment of FIG. 2, method 600 includes controlling the electric compressor 100 to manipulate/control the inlet density of turbocharger compressor 34 in order to compensate for variations in altitude and air filter loading to improve robustness of emissions or assist in thermal management.

[0043] Referring to FIG. 7, another embodiment method 700 is illustrated. Method 700 includes an operation 702 to determine a thermal management condition associated with internal combustion engine system 10. Method 700 includes further an operation 704 to operate the electric compressor 100, 100’ in response to the thermal management condition.

[0044] The thermal management condition can be, for example, any condition in which an increase in the intake air temperature to cylinders 14 and/or exhaust gas temperature is desired from a current temperature. In one instance, one or more operating conditions of system 10 are adjusted so as to achieve one or more target conditions of the intake air and/or exhaust gas in response to the thermal management condition. In some examples, the target condition of the intake air and/or exhaust gas enables effective or more efficient combustion in cylinders 14 and/or operation of the one or more aftertreatment system 26 such that a minimum desired or target operating temperature is obtained and/or maintained.

[0045] In an embodiment of method 700, the electric compressor 100, 100’ is operated in response to the thermal management condition to increase an electrical load on the internal combustion engine 12 to increase a thermal output from the internal combustion engine 12. In an embodiment of method 700, electric compressor 100, 100’ is operated to reduce an intake flow to the internal combustion engine 12 in response to the thermal management condition, In an embodiment of method 700, the electric compressor 100, 100’ is operated to circulate heated intake air to one or more cylinders 14 of the internal combustion engine 12 before starting the internal combustion engine 12 in response to the thermal management condition.

[0046] In an embodiment of method 700, electric compressor 100, 100’ may be utilized to assist in thermal management or engine braking by adding an additional load to the electrical system associated with internal combustion engine 12, thereby increasing crankshaft work. In an embodiment of method 700, electric compressor 100, 100’ is modulated to augment air flow control to increase or decrease the intake air flow to assist in engine braking and/or thermal management.

[0047] In an embodiment of method 700, electric compressor 100, 100’ is used to circulate air that is warmed by an auxiliary heater through EGR system 20 to warm the aftertreatment system 26 before starting the engine 12. The EGR valve 21 can be opened to allow the warmed air to be blown through EGR system 20 by the electric compressor 100, 100’ . In an embodiment of method 700, electric compressor 100, 100’ is controlled to circulate intake air warmed by a grid heater and into one or more cylinders 14 of internal combustion engine 12 while the intake valves are open and internal combustion engine 12 is not operating, such as for a cold start assist before the engine is started.

[0048] Various aspects of the present disclosure are contemplated. In one aspect of the present disclosure, an internal combustion engine system is provided. The system includes an internal combustion engine with an intake system and an exhaust system. The internal combustion engine also includes at least one cylinder for receiving an intake flow for combustion to produce an exhaust flow. The system also includes an electric compressor, and a controller configured to control operation of the electric compressor.

[0049] According to one aspect, an internal combustion engine system is provided that includes an internal combustion engine including an intake and an exhaust. The internal combustion engine includes at least one cylinder for receiving an intake flow from the intake for combustion to produce an exhaust flow to the exhaust. The system includes an electric compressor in the intake configured to compress the intake flow during operation, and a controller configured to operate the electric compressor to compress gas in the intake to diagnose one or more conditions of the internal combustion engine based on a pressure condition of the internal combustion engine produced by the electric compressor. The one or more conditions include a blow-by condition, a leak condition, a pressure sensor fault condition, and a valve condition.

[0050] In an embodiment, the pressure condition is a target pressure condition downstream of the electric compressor based on a speed of the electric compressor. The controller is configured to compare the target pressure condition to a measured pressure condition downstream of the electric compressor, and diagnose the one or more conditions based on a comparison of the target pressure condition to the measured pressure condition. In a further embodiment, the target pressure condition is a boost pressure condition in the intake.

[0051] In an embodiment, the pressure condition is a target boost pressure from the electric compressor. The controller is configured to control an output of the electric compressor in response to the target boost pressure, compare the output of the electric compressor to an expected output for the electric compressor based on the target boost pressure, and diagnose the one or more conditions based on a comparison of the expected output for the compressor and an actual output for the electric compressor.

[0052] In an embodiment, the controller is configured to actuate one of more actuators to isolate the intake, the exhaust, or the one or more cylinders to diagnose the one or more conditions. In a further embodiment, the one or more actuators include an intake throttle, an exhaust valve, and an exhaust gas recirculation valve.

[0053] In an embodiment, the controller is configured to operate the electric compressor to diagnose the one or more conditions while the internal combustion engine is disabled from starting. [0054] According to another aspect of the present disclosure, a method for operating an internal combustion engine including an intake that includes a turbocharger compressor and an electric compressor is provided. The method includes determining a target condition associated with the turbocharger compressor during operation of the internal combustion engine; and operating the electric compressor in response to the target condition of the turbocharger compressor.

[0055] In an embodiment of the method, the target condition is a pressure differential across the turbocharger compressor, and the electric compressor is operated to increase the pressure differential across the turbocharger compressor.

[0056] In an embodiment of the method, the target condition is an outlet temperature of the turbocharger compressor, and the electric compressor is operated to increase the outlet temperature.

[0057] In an embodiment of the method, the target condition is a surge margin of the turbocharger compressor, and the electric compressor is operated to increase the surge margin. [0058] In an embodiment of the method, the target condition is a rotor speed of the turbocharger compressor, and the electric compressor is operated to reduce the rotor speed to avoid cycle fatigue.

[0059] In an embodiment of the method, the target condition is an intake air density at an inlet of the turbocharger compressor, and the electric compressor is operated upstream of the turbocharger compressor to increase the intake air density at the inlet.

[0060] In an embodiment of the method, the electric compressor is upstream of the turbocharger compressor. In another embodiment of the method, the electric compressor is downstream of the turbocharger compressor.

[0061] According to another aspect of the present disclosure, a method for operating an internal combustion engine including an intake that includes an electric compressor and an exhaust the includes an aftertreatment system is provided. The method includes determining a thermal management condition associated with at least one of the engine and the aftertreatment system and operating the electric compressor in response to the thermal management condition.

Operating the electric compressor in response to the thermal management condition includes one or more of: increasing an electrical load on the internal combustion engine using the electric compressor to increase a thermal output from the internal combustion engine; reducing an intake flow to the internal combustion engine using the electric compressor; and circulating heated intake air to one or more cylinders of the internal combustion engine using the electric compressor before starting the internal combustion engine.

[0062] In an embodiment of the method, reducing the intake flow includes throttling the intake flow with the electric compressor. In a further embodiment, the electric compressor is downstream of a turbocharger compressor in the intake.

[0063] In an embodiment of the method, operating the electric compressor in response to the thermal management condition includes operating the electric compressor to circulate air warmed by a heater to the aftertreatment system.

[0064] In an embodiment of the method, operating the electric compressor in response to the thermal management condition includes operating the electric compressor to circulate air warmed by a heater to one or more cylinders of the internal combustion engine.

[0065] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only certain exemplary embodiments have been shown and described and that all changes and modifications that come within the spirit of the inventions are desired to be protected.

[0066] It should be understood that while the use of words such as preferable, preferably, preferred or more preferred utilized in the description above indicate that the feature so described may be more desirable, it nonetheless may not be necessary and embodiments lacking the same may be contemplated as within the scope of the invention, the scope being defined by the claims that follow. In reading the claims, it is intended that when words such as “a,” “an,” “at least one,” or “at least one portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. When the language “at least a portion” and/or “a portion” is used the item can include a portion and/or the entire item unless specifically stated to the contrary.

Claims

What is claimed is:

1. An internal combustion engine system, the system comprising: an internal combustion engine including an intake and an exhaust, the internal combustion engine including at least one cylinder for receiving an intake flow from the intake for combustion to produce an exhaust flow to the exhaust; an electric compressor in the intake configured to compress the intake flow during operation; and a controller configured to operate the electric compressor to compress gas in the intake to diagnose one or more conditions of the internal combustion engine based on a pressure condition of the internal combustion engine produced by the electric compressor, wherein the one or more conditions include a blow-by condition, a leak condition, a pressure sensor fault condition, and a valve condition.

2. The system according to claim 1, wherein the pressure condition is a target pressure condition downstream of the electric compressor based on a speed of the electric compressor, and the controller is configured to: compare the target pressure condition to a measured pressure condition downstream of the electric compressor; and diagnose the one or more conditions based on a comparison of the target pressure condition to the measured pressure condition.

3. The system according to claim 2, wherein the target pressure condition is a boost pressure condition in the intake.

4. The system of claim 1, wherein the pressure condition is a target boost pressure from the electric compressor, and the controller is configured to: control an output of the electric compressor in response to the target boost pressure; compare the output of the electric compressor to an expected output for the electric compressor based on the target boost pressure; and diagnose the one or more conditions based on a comparison of the expected output for the compressor and an actual output for the electric compressor.

5. The system according to claim 1, wherein the controller is configured to actuate one of more actuators to isolate the intake, the exhaust, or the one or more cylinders to diagnose the one or more conditions.

6. The system according to claim 5, wherein the one or more actuators include an intake throttle, an exhaust valve, and an exhaust gas recirculation valve.

7. The system according to claim 1, wherein the controller is configured to operate the electric compressor to diagnose the one or more conditions while the internal combustion engine is disabled from starting.

8. A method for operating an internal combustion engine including an intake that includes a turbocharger compressor and an electric compressor, the method comprising: determining a target condition associated with the turbocharger compressor during operation of the internal combustion engine; and operating the electric compressor in response to the target condition of the turbocharger compressor.

9. The method of claim 8, wherein the target condition is a pressure differential across the turbocharger compressor, and the electric compressor is operated to increase the pressure differential across the turbocharger compressor.

10. The method of claim 8, wherein the target condition is an outlet temperature of the turbocharger compressor, and the electric compressor is operated to increase the outlet temperature.

11. The method of claim 8, wherein the target condition is a surge margin of the turbocharger compressor, and the electric compressor is operated to increase the surge margin.

12. The method of claim 8, wherein the target condition is a rotor speed of the turbocharger compressor, and the electric compressor is operated to reduce the rotor speed to avoid cycle fatigue.

13. The method of claim 8, wherein the target condition is an intake air density at an inlet of the turbocharger compressor, and the electric compressor is operated upstream of the turbocharger compressor to increase the intake air density at the inlet.

14. The method of claim 8, wherein the electric compressor is upstream of the turbocharger compressor.

15. The method of claim 8, wherein the electric compressor is downstream of the turbocharger compressor.

16. A method for operating an internal combustion engine including an intake that includes an electric compressor and an exhaust the includes an aftertreatment system, the method comprising: determining a thermal management condition associated with at least one of the engine and the aftertreatment system; operating the electric compressor in response to the thermal management condition, wherein operating the electric compressor in response to the thermal management condition includes one or more of: increasing an electrical load on the internal combustion engine using the electric compressor to increase a thermal output from the internal combustion engine; reducing an intake flow to the internal combustion engine using the electric compressor; and circulating heated intake air to one or more cylinders of the internal combustion engine using the electric compressor before starting the internal combustion engine.

17. The method of claim 16, wherein reducing the intake flow includes throttling the intake flow with the electric compressor.

18. The method of claim 17, wherein the electric compressor is downstream of a turbocharger compressor in the intake.

19. The method of claim 16, wherein operating the electric compressor in response to the thermal management condition includes operating the electric compressor to circulate air warmed by a heater to the aftertreatment system.

20. The method of claim 16, wherein operating the electric compressor in response to the thermal management condition includes operating the electric compressor to circulate air warmed by a heater to one or more cylinders of the internal combustion engine.