Zero-fuel idling control method and system for range extender

Abstract

The invention discloses a range extender zero fuel idle speed control method and system. The method comprises the steps that a power battery SOC value, a power generation request state and a mechanical accessory work request state are obtained; if the SOC value of the power battery is not lower than the first electric quantity value, no power generation request exists and at least one mechanical accessory working request exists, a pure electric dragging mode is entered, the engine is controlled to stop oil injection, the target torque is zero, the generator drags the engine to rotate at the first target rotating speed not lower than the engine idle speed, and the corresponding mechanical accessory is driven to operate; therefore, pure electric driving of mechanical accessories is achieved under the condition that independent electric accessories are not additionally arranged. Wherein the first electric quantity value is the minimum electric quantity value meeting the requirement of entering a pure electric drag rotation mode; the first target rotating speed is a rotating speed value meeting the working requirement of the corresponding mechanical accessory.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of range extender control, and relates to a range extender zero-fuel idle control method and system. BACKGROUND

[0002] An extended-range electric vehicle (EREV) charges a power battery or directly supplies power through a vehicle-mounted range extender (a combination of an engine and a generator) to extend the cruising range. Normal operation of the vehicle also needs to rely on accessories such as an air conditioner compressor, an air pump, a steering pump, and an engine cooling fan. The driving mode of these accessories is closely coupled with the working mode of the range extender, directly affecting the energy consumption, cost, and safety of the whole vehicle.

[0003] For energy management of the range extender and the accessories, there are various technical solutions, such as integrating and driving the accessories through hardware or using independent electric accessories. However, these related technical solutions all have different degrees of deficiencies, especially in the high energy state (such as an SOC value of 90-100%), the engine cannot be stopped to provide a power source for the accessories, and there is a lack of systematic solutions for zero-fuel consumption of the accessories, low-cost response to high-SOC braking safety, and optimization of various idle-related working conditions. SUMMARY

[0004] Purpose: In view of at least one of the above technical problems, the application provides a range extender zero-fuel idle control method and system, which eliminates fuel consumption for driving mechanical accessories in a high SOC state of the vehicle without increasing or changing hardware (such as not adding electric accessories, clutches, or integrated transmission structures).

[0005] Technical solution: To solve the above technical problems, the technical solution adopted by the application is as follows: In a first aspect, a range extender zero-fuel idle control method is provided, comprising: obtaining a power battery SOC value, a power generation request state, and a mechanical accessory working request state; If the power battery SOC value is not lower than a first energy value, there is no power generation request, and at least one mechanical accessory working request, a pure electric drag mode is entered, the engine is controlled to stop fuel injection and the target torque is zero, the generator drags the engine to rotate at a first target speed not lower than the engine idle speed, and drives the corresponding mechanical accessory to operate, thereby realizing pure electric driving of the mechanical accessory without adding independent electric accessories; wherein the first energy value is the minimum energy value that meets the entering of the pure electric drag mode; and the first target speed is a speed value that meets the working demand of the corresponding mechanical accessory.

[0006] In some embodiments, the range extender zero-fuel idle control method further comprises idle power consumption mode control: If the vehicle is in a coasting or braking state, the SOC value of the power battery is not lower than the second charge value, there is no power generation request, and the vehicle drive motor is performing energy recovery, it enters the pure electric towing mode, controls the engine to stop injecting fuel and the target torque is zero, and the generator drives the engine to rotate at a second target speed not lower than the engine idle speed, wherein the second charge value is greater than or equal to the first charge value. Furthermore, if at least one mechanical accessory requests operation, the second target rotational speed is the rotational speed value that satisfies the operation requirements of the corresponding mechanical accessory.

[0007] In some embodiments, the range extender zero-fuel idle speed control method further includes start-up process optimization control: When the engine starts, if the SOC value of the power battery is not lower than the third charge value, it first enters the pure electric towing mode, controls the generator to drive the engine to rotate at the third target speed, which is not lower than the engine idle speed. After the engine reaches the fourth target speed, the engine injects fuel and ignites. The third electrical quantity value is the minimum electrical quantity value that can satisfy the generator to drive the engine to rotate at the third target speed.

[0008] In some embodiments, the range extender zero-fuel idle speed control method further includes control for rapidly establishing oil pressure after engine start: After the engine starts, if the SOC value of the power battery is not lower than the fourth charge value, it enters the pure electric towing mode and controls the generator to drive the engine to rotate at the fourth target speed, which is not lower than the engine idle speed, so as to achieve rapid establishment of oil pressure. The fourth electrical quantity value is the minimum electrical quantity value that can satisfy the generator to drive the engine to rotate at the fourth target speed.

[0009] In some embodiments, the range extender zero-fuel idling control method further includes delayed shutdown control before shutdown: After the engine completes its power generation task, if the engine cooling system or engine after-treatment system needs to continue working, and the SOC value of the power battery is not lower than the fifth charge value, it enters the pure electric traction mode, controls the engine to stop injecting fuel and the target torque is zero, and the generator drives the engine to rotate at the first target speed and drives the corresponding mechanical accessories to operate, achieving delayed operation with zero fuel consumption.

[0010] In some embodiments, the range extender zero-fuel idling control method further includes control for exiting the pure electric traction mode: In pure electric towing mode, if the SOC value of the power battery drops to no more than the sixth charge value, and / or there is a power generation request, the system exits the pure electric towing mode, controls the engine to resume normal fuel injection operation, and the generator switches to power generation mode. The sixth energy value is the maximum energy value required to exit the pure electric towing mode.

[0011] In some embodiments, the range extender zero-fuel idling control method allows for an adjustable target speed of the generator in pure electric tractor mode, and the generator speed is not located in the engine idling resonance zone.

[0012] In some embodiments, the mechanical accessory includes at least one of an air conditioning compressor, an air pump, a steering pump, a low-voltage generator, and an engine cooling fan.

[0013] In some embodiments, the generator is an ISG motor.

[0014] Secondly, a range extender control unit is provided, including a processor and a storage medium; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps according to the method.

[0015] Thirdly, a zero-fuel idling control system for a range extender is provided, including the aforementioned range extender control unit.

[0016] Fourthly, a range-extended electric vehicle is provided, equipped with the range extender control unit or the range extender zero-fuel idle speed control system.

[0017] Compared with the prior art, the beneficial effects achieved by this application are as follows: Fuel saving and emission reduction across the entire range: Completely eliminates fuel consumption and emissions under various traditional fuel-consuming operating conditions such as mechanical accessory drive, start-up, pressure building, and delayed shutdown under high SOC (SOC value ≥ 70%).

[0018] Ultimate cost-effectiveness: By implementing a pure software control strategy to achieve hardware multifunctionality, the electric accessory system achieves zero-fuel drive effect without the need for additional hardware costs, while retaining low-cost mechanical accessories.

[0019] Enhanced driving safety: Provides a zero-fuel active energy consumption method to effectively ensure braking safety under high SOC conditions.

[0020] Improved noise and vibration performance: Electronically adjustable target speed allows the system to actively avoid the engine idling resonance zone, improving quietness and smoothness.

[0021] Enhanced user experience: It achieves zero-fuel air conditioning supply, providing a more economical and quieter pure electric vehicle experience. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of a zero-fuel idling control system for a range extender according to an embodiment of this application. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use.

[0025] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to explain the relative positional relationship and movement between components in a specific orientation. If the specific orientation changes, the directional indication will also change accordingly. These terms are used only for the convenience of describing this application and for simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0026] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0027] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0028] None of the relevant technologies can systematically solve the series of problems related to zero-fuel drive accessories, zero-fuel safe power consumption, and zero-fuel operation under multiple operating conditions through a single, unified control method without significant changes or additions to the hardware. This leads to a dilemma: either sacrifice energy efficiency and comfort (using mechanical accessories) or sacrifice cost and simplicity (using electric accessories). The root cause lies in the failure to fully utilize the powerful electric drive unit—the existing generator—in the hybrid system, and to reconstruct the drive mode of the accessories through innovative control strategies, thereby breaking this "either / or" predicament.

[0029] Given the shortcomings of related technologies, this application aims to solve the following technical problems: 1. Eliminate fuel consumption caused by driving accessories under high SOC conditions without adding or changing hardware (such as without adding electric accessories, clutches or integrated transmission structures).

[0030] 2. To provide a zero-fuel active energy consumption method to solve the problem of auxiliary braking failure caused by limited energy recovery under high SOC, and to ensure driving safety.

[0031] 3. Avoid resonance problems that may be caused by the fixed idle point of traditional engines, and improve the vehicle's NVH (noise, vibration and harshness) performance.

[0032] 4. Provides a unified control method that flexibly covers various operating conditions that require the range extender to "idle" or "consume power," such as the start-up process, idle pressure build-up after start-up, high SOC without shutdown, pure electric air conditioning, and delayed shutdown before shutdown.

[0033] Example 1: This application provides a zero-fuel idling speed control method for a range extender, comprising: Obtain the SOC value of the power battery, the power generation request status, and the mechanical accessory work request status; If the SOC value of the power battery is not lower than a first charge value (e.g., 70%), there is no power generation request, and at least one mechanical accessory has a working request, the system enters a pure electric towing mode. The engine stops injecting fuel and the target torque is zero. The generator drives the engine to rotate at a first target speed N1, which is not lower than the engine idle speed, and drives the corresponding mechanical accessory to operate. This achieves pure electric drive of the mechanical accessory without adding an independent electric accessory. The first charge value is the minimum charge value required to enter the pure electric towing mode. The first target speed N1 is the speed value required to meet the working requirements of the corresponding mechanical accessory.

[0034] In some embodiments, the range extender zero-fuel idling control method further includes idling power consumption mode control: If the vehicle is coasting or braking, the SOC value of the power battery is not lower than the second charge value (e.g., 70-85%), there is no power generation request, and the vehicle's drive motor is performing energy recovery, it enters the pure electric towing mode. The engine stops injecting fuel and the target torque is zero. The generator drives the engine to rotate at a second target speed N2, which is not lower than the engine's idle speed. The second charge value is greater than or equal to the first charge value. It should be noted that even if there is no mechanical accessory working request at this time, the generator will still drive the engine to idle, actively consuming electrical energy to free up capacity for continuous energy recovery and ensure effective auxiliary braking. Furthermore, if at least one mechanical accessory requests operation, the second target rotational speed N2 is the rotational speed value that satisfies the operation requirements of the corresponding mechanical accessory.

[0035] In some embodiments, the range extender zero-fuel idling control method further includes start-up process optimization control: When the engine starts, if the SOC value of the power battery is not lower than the third charge value (e.g., 10%), it first enters the pure electric towing mode, controls the generator to drive the engine to rotate at the third target speed N3, which is not lower than the engine idle speed. After the engine reaches the fourth target speed, the engine injects fuel and ignites. The third electrical quantity value is the minimum electrical quantity required to allow the generator to drive the engine at the third target speed N3. Optimizing the startup process as described above improves startup smoothness.

[0036] In some embodiments, the range extender zero-fuel idling control method further includes control for rapidly establishing oil pressure after engine start: After the engine starts, if the SOC value of the power battery is not lower than the fourth charge value (e.g., 10%), it enters the pure electric towing mode and controls the generator to drive the engine to rotate at the fourth target speed N4, which is not lower than the engine idle speed, so as to achieve rapid establishment of oil pressure. The fourth electrical quantity value is the minimum electrical quantity value that can satisfy the generator to drive the engine to rotate at the fourth target speed N4.

[0037] In some embodiments, the range extender zero-fuel idling control method further includes delayed shutdown control before shutdown: After the engine completes its power generation task, if the engine cooling system or engine after-treatment system needs to continue working, and the SOC value of the power battery is not lower than the fifth charge value (e.g., 10%), it enters the pure electric traction mode, controls the engine to stop injecting fuel and the target torque to be zero, and the generator drives the engine to rotate at the first target speed N1 and drives the corresponding mechanical accessories to operate, achieving delayed operation with zero fuel consumption.

[0038] In some embodiments, the range extender zero-fuel idling control method further includes a control for exiting the pure electric tractor mode: In pure electric towing mode, if the SOC value of the power battery drops to no more than the sixth charge value (e.g., 30%), and / or there is a power generation request, the system exits the pure electric towing mode, controls the engine to resume normal fuel injection operation, and the generator switches to power generation mode. The sixth energy value is the maximum energy value required to exit the pure electric towing mode.

[0039] It should be noted that, for the power batteries of the same type of vehicle, in some embodiments, the second charge value (e.g., 70~85%) ≥ the first charge value (e.g., 70%) > the sixth charge value (e.g., 30%) > the third charge value (e.g., 10%) = the fourth charge value (e.g., 10%) = the fifth charge value (e.g., 10%).

[0040] In some embodiments, the mechanical accessories include at least one of an air conditioning compressor, an air pump, a steering pump, a low-voltage generator (such as a 24V low-voltage generator), and an engine cooling fan.

[0041] In some embodiments, in the range extender zero-fuel idling control method, in pure electric tractor mode, the target speed of the generator is adjustable and not located in the engine idling resonance zone. The target speed can be set outside the known engine idling resonance zone, thereby improving NVH performance.

[0042] In this embodiment, the generator is an ISG motor. The ISG motor is an intelligent starter generator integrated into the crankshaft end of the engine, which can realize pure electric drive, energy recovery, and power assistance.

[0043] Example 2: This application provides a range extender control unit, including a processor and a storage medium; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps according to the method.

[0044] Example 3: As Figure 1 As shown, this application provides a range extender zero-fuel idling control system, including the range extender control unit (i.e., range extender control unit RCU) described in Embodiment 2. The range extender control unit includes a processor and a storage medium; the storage medium is used to store instructions; the processor is used to operate according to the instructions to execute the steps of the following range extender zero-fuel idling control method. In some embodiments, such as Figure 1As shown, the range extender zero-fuel idling control system also includes an engine, a generator, an engine controller (ECU), a generator controller (GCU), a vehicle controller (VCU), mechanical accessories, and energy storage components. The vehicle control unit (VCU) is responsible for top-level decision-making and mode requests. The range extender control unit (RCU), as the core actuator, manages the operating status of the range extender (engine and generator), receives commands from the VCU, and coordinates with the ECU and GCU to execute corresponding responses. In this embodiment, the engine controller (ECU) receives commands from the RCU to control the engine's operating status; the generator controller (GCU) receives commands from the RCU to control the generator's operating status.

[0045] Energy flow: The electrical energy of the energy storage element is converted from AC to DC by the generator controller GCU and flows to the generator. The generator acts as a motor and outputs torque Tm, which on the one hand overcomes the frictional resistance of the engine, and on the other hand drives the mechanical accessories to work.

[0046] Control signals: The vehicle control unit (VCU) sends mode, status, and power request commands to the range extender control unit (RCU); in pure electric towing mode, the range extender control unit (RCU) sends a command to the engine control unit (ECU) to "stop fuel injection, target torque is 0"; the range extender control unit (RCU) sends a command to the generator controller (GCU) to "control mode, target speed".

[0047] In some embodiments, the range extender zero-fuel idling control system further includes an electric energy management system (EMS) for monitoring the state of charge (SOC) value of the power battery.

[0048] The range extender zero-fuel idling control system provided in this application (1) reuses the mechanical accessory system as a quasi-electric accessory system through innovative control strategies. The drive source of the accessory is defined by the software program, realizing the multi-functionality of the hardware platform and fundamentally avoiding the cost of adding electric accessories. (2) The target speed is adjustable to avoid resonance. The range extender control unit RCU / vehicle control unit VCU can set the target speed outside the known engine idling resonance zone, thereby improving NVH performance. (3) "Mode reuse". The pure electric towing mode is reused for "idling power consumption" and various extended operating conditions, and the safety and energy consumption problems under high SOC are solved with a single control strategy.

[0049] Example 4: This application provides a range-extended electric vehicle, which is equipped with the range extender control unit or the range extender zero-fuel idling control system.

[0050] The range-extended electric vehicles include not only passenger cars and commercial range-extended electric vehicles, but also plug-in hybrid electric vehicles (PHEVs) and non-road mobile machinery such as engineering machinery based on the range-extended principle.

[0051] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0052] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0053] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0054] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0055] The above description is only a preferred embodiment of this application. It should be noted that those skilled in the art should understand that various changes and improvements may be made to this application without departing from the principles and spirit. These improvements should also be considered within the scope of protection of this application and are not limited to the above embodiments.

Claims

1. A method for controlling zero-fuel idling speed in a range extender, characterized in that, include: Obtain the SOC value of the power battery, the power generation request status, and the mechanical accessory work request status; If the SOC value of the power battery is not lower than the first charge value, there is no power generation request, and at least one mechanical accessory has a working request, the system enters the pure electric towing mode. The engine stops injecting fuel and the target torque is zero. The generator drives the engine to rotate at a first target speed not lower than the engine idle speed, and drives the corresponding mechanical accessory to operate. This achieves pure electric drive of the mechanical accessory without adding an independent electric accessory. The first charge value is the minimum charge value required to enter the pure electric towing mode. The first target speed is the speed value required to meet the working requirements of the corresponding mechanical accessory.

2. The zero-fuel idling speed control method for a range extender according to claim 1, characterized in that, It also includes idle power consumption mode control: If the vehicle is in a coasting or braking state, the SOC value of the power battery is not lower than the second charge value, there is no power generation request, and the vehicle drive motor is performing energy recovery, it enters the pure electric towing mode, controls the engine to stop injecting fuel and the target torque is zero, and the generator drives the engine to rotate at a second target speed not lower than the engine idle speed, wherein the second charge value is greater than or equal to the first charge value. Furthermore, if at least one mechanical accessory requests operation, the second target rotational speed is the rotational speed value that satisfies the operation requirements of the corresponding mechanical accessory.

3. The zero-fuel idling speed control method for a range extender according to claim 1, characterized in that, It also includes startup process optimization control: When the engine starts, if the SOC value of the power battery is not lower than the third charge value, it first enters the pure electric towing mode, controls the generator to drive the engine to rotate at the third target speed, which is not lower than the engine idle speed. After the engine reaches the fourth target speed, the engine injects fuel and ignites. The third electrical quantity value is the minimum electrical quantity value that can satisfy the generator to drive the engine to rotate at the third target speed.

4. The zero-fuel idling speed control method for a range extender according to claim 1, characterized in that, This also includes control for quickly establishing oil pressure after engine start-up: After the engine starts, if the SOC value of the power battery is not lower than the fourth charge value, it enters the pure electric towing mode and controls the generator to drive the engine to rotate at the fourth target speed, which is not lower than the engine idle speed, so as to achieve rapid establishment of oil pressure. The fourth electrical quantity value is the minimum electrical quantity value that can satisfy the generator to drive the engine to rotate at the fourth target speed.

5. The zero-fuel idling speed control method for a range extender according to claim 1, characterized in that, It also includes delayed shutdown control before shutdown: After the engine completes its power generation task, if the engine cooling system or engine after-treatment system needs to continue working, and the SOC value of the power battery is not lower than the fifth charge value, it enters the pure electric traction mode, controls the engine to stop injecting fuel and the target torque is zero, and the generator drives the engine to rotate at the first target speed and drives the corresponding mechanical accessories to operate, achieving delayed operation with zero fuel consumption.

6. The zero-fuel idling speed control method for a range extender according to claim 1, characterized in that, It also includes exit control for pure electric towing mode: In pure electric towing mode, if the SOC value of the power battery drops to no more than the sixth charge value, and / or there is a power generation request, the system exits the pure electric towing mode, controls the engine to resume normal fuel injection operation, and the generator switches to power generation mode. The sixth energy value is the maximum energy value required to exit the pure electric towing mode.

7. The zero-fuel idling speed control method for a range extender according to any one of claims 1-6, characterized in that, In pure electric traction mode, the target speed of the generator is adjustable and is not located in the engine idling resonance zone.

8. The zero-fuel idling speed control method for a range extender according to claim 1, characterized in that, The mechanical accessories include at least one of the following: air conditioning compressor, air pump, steering pump, low-voltage generator, and engine cooling fan.

9. The zero-fuel idling speed control method for a range extender according to claim 1, characterized in that, The generator is an ISG motor.

10. A range extender control unit, characterized in that, Including processor and storage media; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to any one of claims 1 to 9.

11. A zero-fuel idling control system for a range extender, characterized in that, Includes the range extender control unit as described in claim 10.

12. A range-extended electric vehicle, characterized in that, It is equipped with the range extender control unit as described in claim 10 or the range extender zero-fuel idling control system as described in claim 11.

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