Range-extending vehicle engine auxiliary shutdown method, generator controller and vehicle

Abstract

The invention relates to an extended-range vehicle engine auxiliary shutdown method, a generator controller and an automobile, and the method comprises the following steps: responding to a shutdown instruction sent by a domain controller, and enabling a generator to enter a shutdown mode; in this mode, the generator controller first reduces the rotational speed. And when the rotating speed of the generator is reduced to the first preset rotating speed, the generator controller generates a mapping relation between the engine crankshaft position and the generator rotating position. And then, the generator controller accurately controls the generator to rotate according to the resolver position of the generator at the current moment and the mapping relation, so that the generator drives the engine to stop at the preset stop position. According to the method, the effect of improving the NVH performance in the shutdown process and the restart process is achieved.

Description

Technical Field

[0001] This invention relates to the field of range-extended hybrid electric vehicles, specifically to a method for assisting engine shutdown in a range-extended vehicle, a generator controller, and the vehicle itself. Background Technology

[0002] To further reduce fuel consumption, range-extended hybrid electric vehicles (REEVs) typically employ high-compression, Miller-cycle gasoline engines. To reduce vibration and noise while transmitting torque, a torque limiter is usually used to connect the engine and generator. During engine shutdown, the rapid change in cylinder pressure causes large fluctuations in engine speed, noticeable vibration, and significant knocking of the torque limiter. When restarting the engine after shutdown, if the piston is near its bottom dead center, the effective compression ratio is at its maximum during startup, causing a sudden change in cylinder pressure near the top dead center. This rapid increase in cylinder pressure leads to oscillation, resulting in significant cylinder block vibration and poor overall vehicle NVH (Noise, Vibration, Harshness) experience. Therefore, controlling the piston's stopping position during shutdown can improve NVH performance during startup. Based on this, engine shutdown process control in REEVs has a significant impact on overall vehicle performance. Summary of the Invention

[0003] One objective of this invention is to provide an engine-assisted shutdown method for a range-extended vehicle to improve NVH performance during shutdown and restart; another objective is to provide a generator controller; and a third objective is to provide a vehicle.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A method for assisted engine shutdown in a range-extended vehicle includes:

[0006] In response to a shutdown command sent by the domain controller, the generator is controlled to enter shutdown mode;

[0007] The shutdown mode includes: controlling the generator to reduce its speed, and when the generator speed is reduced to a first preset speed, generating a mapping relationship between the crankshaft position of the engine and the resolver position of the generator; and controlling the generator to rotate according to the resolver position of the generator at the current moment and the mapping relationship, so that the generator drives the engine to complete the shutdown at the preset shutdown position.

[0008] In one example, controlling the generator to rotate based on the generator's current resolver position and the mapping relationship, so that the generator drives the engine to stop at a preset stopping position, includes:

[0009] Based on the mapping relationship, the current resolver position of the generator, and at least one preset shutdown position of the engine, the target shutdown position of the generator is determined;

[0010] Based on the resolver position of the generator and the target shutdown position, the generator is controlled to rotate so that the generator drives the engine to stop at the preset shutdown position.

[0011] In one example, determining the target shutdown position of the generator based on the mapping relationship, the resolver position of the generator at the current moment, and at least one preset shutdown position of the engine includes:

[0012] According to the mapping relationship, at least one preset stop position of the engine is converted into at least one mapped stop position of the generator;

[0013] Based on the resolver position of the generator at the current moment, a target shutdown position is selected from at least one of the mapped shutdown positions.

[0014] In one example, selecting a target shutdown position from at least one of the mapped shutdown positions based on the resolver position of the generator at the current moment includes:

[0015] If the difference between the current resolver position of the generator and the nearest mapped shutdown position is less than or equal to a first threshold, then the next mapped shutdown position after the nearest mapped shutdown position is determined as the target shutdown position.

[0016] If the difference between the current resolver position of the generator and the nearest mapped shutdown position is greater than a first threshold, then the nearest mapped shutdown position is determined as the target shutdown position.

[0017] In one example, controlling the generator to rotate based on the resolver position and the target stopping position, so that the generator drives the engine to stop at a preset stopping position, includes:

[0018] When the difference between the resolver position and the target stop position of the generator reaches a second threshold, after a first preset time, the generator is de-torqueed so that the torque of the generator drops to 0 according to a preset torque smoothing curve; wherein the second threshold is less than the first threshold.

[0019] In one example, controlling the generator to reduce its speed includes:

[0020] The engine speed sequence is generated based on the generator's current speed and a preset speed decrease slope;

[0021] The generator is controlled to adjust its speed according to the speed sequence in order to reduce the speed of the generator.

[0022] In one example, the method further includes:

[0023] After generating the mapping relationship between the crankshaft position of the engine and the resolver position of the generator, the crankshaft position of the engine and the resolver position of the generator are continuously collected.

[0024] The mapping relationship is corrected based on the crankshaft position of the engine and the resolver position of the generator.

[0025] In one example, the method further includes:

[0026] In response to a shutdown command, the generator is switched to speed control mode;

[0027] When the speed of the generator decreases to the first preset speed, the generator is switched to angle control mode;

[0028] When the difference between the resolver position and the target stop position of the generator reaches a second threshold, the generator is switched to torque control mode.

[0029] In one example, the method further includes:

[0030] In response to an exit command sent by the domain controller, the generator is controlled to exit the shutdown mode;

[0031] The exit from the shutdown mode includes: controlling the generator to delay for a second preset time before ending the shutdown;

[0032] The exit command is generated when the generator speed is less than a second preset speed.

[0033] A generator controller includes: a memory and a processor;

[0034] The memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory, causing the processor to perform the above-described method.

[0035] An automobile includes a vehicle body, a domain controller, a torque limiter, an engine, a generator, and a generator controller; the generator and the engine are coaxially connected via the torque limiter; the generator controller is communicatively connected to the domain controller.

[0036] The beneficial effects of this invention are:

[0037] This invention ensures that the effective compression ratio of the cylinder that reaches the top dead center of the compression stroke first is minimized and cylinder pressure oscillation is minimized by controlling all cylinders of the engine to be on the same horizontal plane when the engine is stopped. This improves the NVH performance during the shutdown process and when the engine is restarted. Attached Figure Description

[0038] Figure 1This is a schematic diagram of the engine shutdown system provided by the present invention;

[0039] Figure 2 A schematic flowchart illustrating the range-extended vehicle engine assisted shutdown method provided by the present invention;

[0040] Figure 3 A schematic diagram illustrating the mapping relationship between the crankshaft position of the engine and the resolver position of the generator, provided for the present invention;

[0041] Figure 4 A schematic diagram showing the position of the engine crankshaft within the cylinder, provided by the present invention;

[0042] Figure 5 A schematic flowchart illustrating the range-extended vehicle engine assisted shutdown method provided by the present invention;

[0043] Figure 6 This is a schematic diagram of the structure of the range-extended vehicle engine auxiliary shutdown device provided by the present invention;

[0044] Figure 7 This is a schematic diagram of the generator controller provided by the present invention.

[0045] Figure Labels

[0046] 101-Domain Controller; 102-Generator Controller; 103-Generator; 104-Resolver Sensor; 105-Torque Limiter; 106-Crankshaft Sensor; 107-Engine; 108-Engine Controller; 301-First Position; 302-Second Position; 303-Crankshaft; 304-Third Position; 305-Fourth Position; 600-Range Extender Vehicle Engine Auxiliary Shutdown Device; 601-Shutdown Module; 602-Exit Module; 701-Processor; 702-Memory; 703-Communication Components; 704-Bus. Detailed Implementation

[0047] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0048] The purpose of this invention is to provide a systematic control method for engine shutdown systems to improve noise, vibration, and harshness (NVH) performance during shutdown and restart. To achieve this objective, this invention proposes a control method for an engine shutdown system applied to the assisted shutdown process of a range-extended vehicle engine.

[0049] The engine shutdown system of this invention can be as follows: Figure 1 As shown. Figure 1 As shown, the engine shutdown system includes a domain controller 101, a generator controller 102, a generator 103, a resolver sensor 104, a torque limiter 105, a crankshaft sensor 106, an engine 107, and an engine controller 108.

[0050] The engine shutdown system includes an engine 107 and a generator 103. The generator 103 and engine 107 are actuators. The generator 103 and engine 107 are coaxially connected via a torque limiter 105.

[0051] In one implementation, to reduce fuel consumption, the engine 107 used in this embodiment of the invention is a high compression ratio Miller cycle gasoline engine.

[0052] In one implementation, engine 107 can be a four-cylinder engine.

[0053] The crankshaft sensor 106 is used to detect the crankshaft position in the engine 107. The resolver sensor 104 is used to detect the resolver position of the generator 103.

[0054] The engine 107 can be controlled by the engine controller 108. Specifically, the engine controller 108 can be an Engine Management System (EMS). As the controller of the engine 107, the engine controller 108 is responsible for controlling the normal operation of the engine 107 and sending the crankshaft position to the CAN bus in real time. This crankshaft position is an integer from 1 to 60.

[0055] The generator can be controlled by the generator controller 102. Specifically, the generator controller 102 can be a single power electronic unit (SPEU). As the controller of the generator 103, the generator controller 102 is responsible for controlling the normal operation of the generator 103 and sending the generator speed to the CAN bus in real time.

[0056] The engine shutdown system may also include a domain controller 101. This domain controller 101 can be a power control unit (PCU). The domain controller 101 can act as a host computer for the generator controller 102 and the engine controller 108, sending start-up, shutdown, and operation commands to them. The domain controller 101, generator controller 102, and engine controller 108 are connected via a CAN bus.

[0057] In one implementation, when a shutdown is required, the domain controller 101 sends an auxiliary shutdown status command to the generator controller 102 and the engine controller 108. Upon receiving the command, the engine controller 108 cuts off the fuel supply to the engine 107. The generator controller 102 first controls the speed of the generator 103 and gradually and steadily reduces it. When the speed of the generator 103 decreases to the first target speed, the generator controller 102 needs to map or learn the crankshaft position sent in real time by the engine controller 108 onto the resolver position of the generator 103. Then, the generator controller 102 precisely controls the rotation position of the generator 103 based on the resolver position until the crankshaft of the engine 107 stops at the preset shutdown position.

[0058] When the engine 107 is stopped, the crankshaft of each cylinder of the engine 107 is controlled to stop at the preset stop position. This ensures that when the engine 107 is started again, all cylinders are on the same horizontal plane. This ensures that the effective compression ratio of the cylinder that reaches the top dead center of the compression is the smallest and the cylinder pressure oscillation is the smallest when the engine is started again. This solves the problem of poor NVH experience caused by cylinder pressure oscillation during hot engine start-up.

[0059] In one implementation, there are two preset shutdown positions within one revolution of the engine 107 crankshaft. Therefore, there are also two target shutdown positions for the generator 103 within one revolution.

[0060] The technical solution of the present invention and how the technical solution of the present invention solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of the present invention will now be described with reference to the accompanying drawings.

[0061] Figure 2 This is a flowchart illustrating the range-extended vehicle engine assisted shutdown method provided by the present invention. Figure 1 Based on the engine shutdown system shown, as Figure 2 As shown, applied to a generator controller, the method includes:

[0062] S201. In response to a shutdown command sent by the domain controller, control the generator to enter shutdown mode.

[0063] For example, the domain controller can send a shutdown command to the generator controller when it detects that the vehicle needs to be shut down. In response to the shutdown command, the generator controller can immediately start the corresponding program to control the generator to enter shutdown mode.

[0064] In one implementation, the shutdown command is a specific signal issued by the domain controller to instruct the generator to stop running and enter a shutdown state.

[0065] In one implementation, the generator controller and the domain controller are connected via cables. For example, data transmission can be performed using communication protocols such as Controller Area Network (CAN) bus.

[0066] In one implementation, the generator controller and the domain controller are connected wirelessly. For example, wireless communication networks such as Bluetooth and Wi-Fi can be used.

[0067] In one example, after the generator controller puts the generator into shutdown mode, the generator controller can perform the following steps:

[0068] S2011. Control the generator to reduce its speed, and when the generator speed is reduced to the first preset speed, generate a mapping relationship between the crankshaft position of the engine and the resolver position of the generator.

[0069] For example, the generator controller sends a control signal to the generator to reduce its speed. The generator gradually reduces its rotational speed according to this control signal. Simultaneously, the generator controller can also acquire the generator's resolver signal in real time via a resolver sensor and determine the generator's speed based on this resolver signal, thus achieving continuous monitoring of the generator's speed.

[0070] When the generator controller detects that the generator speed has dropped to the first preset speed, it can obtain the crankshaft position of the engine and the resolver position of the generator at this time, and establish a mapping relationship between the two.

[0071] In one implementation, the first preset speed is a relatively low speed. For example, the first preset speed can be a value around 100 rpm, such as 110 rpm, 100 rpm, or 90 rpm. When the generator speed decreases to this first preset speed, it indicates that the generator controller can perform subsequent shutdown operations, thereby ensuring shutdown at the target shutdown position.

[0072] In one implementation, the generator controller can start acquiring the crankshaft position of the engine and the resolver position of the generator when the difference between the engine speed and the first preset engine speed is less than a preset difference, thereby generating a mapping relationship.

[0073] In one implementation, the crankshaft position of the engine reflects the movement position of the engine pistons. For example, as... Figure 4 As shown, the crankshaft 303 rotates counterclockwise within the cylinder of the engine. The second position 302 and the fourth position 305 are preset stop positions. The second position 302 and the fourth position 305 represent the horizontal positions of the crankshaft within the cylinder. The first position 301 and the third position 304 represent the vertical positions of the crankshaft within the cylinder.

[0074] In one implementation, the resolver position of the generator can accurately reflect the rotation angle of the generator rotor.

[0075] In one implementation, the mapping relationship refers to a correspondence between the crankshaft position of the engine and the resolver position of the generator. Based on this mapping relationship, the position information of the other can be deduced when the position information of one is known. For example, this mapping relationship can be as follows: Figure 3 As shown.

[0076] in, Figure 3 The position above is the rotation position. Figure 3 Below this is the crankshaft position. The crankshaft position value is between 1 and 60. The corresponding resolver positions are 6 0-360 degrees.

[0077] S2012. Based on the resolver position and mapping relationship of the generator at the current moment, control the generator to rotate so that the generator drives the engine to stop at the preset stop position.

[0078] For example, the generator controller can obtain the resolver position of the generator in real time. At the same time, the generator controller can call the pre-generated mapping relationship between the engine crankshaft position and the generator resolver position to complete the conversion between the generator's resolver position at the current moment and the engine's preset shutdown position, thereby enabling the engine to stop at the preset shutdown position during the gradual shutdown process of the generator.

[0079] In one implementation, the preset stopping position is a specific position that the engine is expected to reach when it stops. For example, such as... Figure 4 As shown, the preset stopping positions can be the second position 302 and the fourth position 305. These two positions ensure that the stopping positions of each cylinder of the engine are on the same horizontal plane.

[0080] Optionally, these two positions can correspond to teeth 29 and 59, respectively. Specifically, the second position 302 can correspond to tooth 29, and the fourth position 305 can correspond to tooth 59. Since the crankshaft positions of the engine are recorded as teeth 1-60, teeth 29 and 59 can be the positions corresponding to the teeth with these two serial numbers when sorted according to a preset method. Figure 4In the positions shown, teeth 29 and 59 correspond to the horizontal position.

[0081] Optionally, when the numerical marking method of each tooth of the crankshaft is different, the tooth numbers corresponding to the two positions 302 and 305 will also be different.

[0082] In one implementation, the generator controller can directly calculate, through open-loop control and a mapping relationship, the angle and direction of rotation required by the generator to move the engine from its current resolver position to its preset stop position. Then, the generator controller can issue fixed control commands to the generator, driving it to rotate so that the generator can stop the engine at the preset stop position.

[0083] Optionally, during this process, the generator controller may not provide real-time feedback on the actual position information of the engine or generator, but may rely solely on pre-calculated parameters for control.

[0084] In another implementation, the generator controller can achieve generator shutdown control through closed-loop control. The generator controller reads the resolver position of the generator in real time. The generator controller can compare the resolver position with the expected position. If there is a deviation between the resolver position and the expected position, the generator controller adjusts the control commands in a timely manner until the engine accurately reaches the preset shutdown position.

[0085] In this example, by responding to the shutdown command sent by the domain controller, the generator speed is controlled to decrease. When the speed decreases to a first preset speed, a mapping relationship between the engine crankshaft position and the generator resolver position is generated. Then, based on the current resolver position and the mapping relationship, the generator is controlled to rotate, so that the generator drives the engine to stop at the preset position. This achieves the effect of controlling the engine to stop at the target position, thereby avoiding vehicle vibration, improving vehicle NVH performance, and enhancing the user experience.

[0086] In one example, step S2012 above, the specific process of controlling the generator to rotate until it stops, may include:

[0087] S20121. Determine the target shutdown position of the generator based on the mapping relationship, the resolver position of the generator at the current moment, and at least one preset shutdown position of the engine.

[0088] For example, the generator controller can match the generator's current resolver position with at least one preset shutdown position of the engine based on the mapping relationship between the engine crankshaft position and the generator resolver position generated in step S2011 above, thereby determining a preset shutdown position that meets the requirements. Furthermore, the generator controller can determine the target shutdown position in the generator corresponding to the preset shutdown position of the engine based on this mapping relationship.

[0089] In one implementation, the generator controller can first map the current resolver position to the engine based on the mapping relationship, then match the mapped resolver position with at least one preset shutdown position to determine the preset shutdown position that meets the requirements, and then determine the corresponding target shutdown position in the generator.

[0090] In another implementation, the generator controller can first map at least one preset stop position to the engine according to the mapping relationship, then match the mapped preset stop position with the current resolver position to determine the qualified mapped preset stop position, and use the mapped preset stop position as the target stop position.

[0091] In one implementation, the resolver position of the generator at the current moment can be the resolver position obtained by the generator controller after the generator controller completes the generation of the mapping relationship.

[0092] In one implementation, the preset stopping position that meets the requirements can be a preset stopping position whose distance from the current resolver position is greater than a stopping distance. This stopping distance can be the minimum distance the resolver needs to move from 100 rpm to 0 rpm. For example, this stopping distance can be 5 teeth. Optionally, since the crankshaft position is denoted as teeth 1-60, 5 teeth represents 30 degrees.

[0093] S20122. Based on the resolver position of the generator and the target shutdown position, control the generator to rotate so that the generator drives the engine to complete the shutdown at the preset shutdown position.

[0094] For example, after determining the target shutdown position, the generator controller can acquire the resolver position of the generator in real time. The generator controller can compare the target shutdown position with the real-time acquired resolver position, calculate the angle difference between the two, and then generate control commands for the generator to control the generator to rotate, so that the resolver position of the generator continuously approaches the target shutdown position. When the resolver position of the generator reaches the target shutdown position, the crankshaft of the engine, which is coaxial with the generator, rotates to the preset shutdown position corresponding to the target shutdown position.

[0095] In this example, by determining the target shutdown position in the generator based on the mapping relationship and controlling the generator rotation accordingly, the engine is precisely shut down. This improves the accuracy of engine shutdown position control, thereby avoiding vehicle vibration, improving vehicle NVH performance, and enhancing the user experience.

[0096] In one example, in step S20121 above, the generator controller determines the target shutdown position of the generator, and the specific process includes:

[0097] S201211. Based on the mapping relationship, at least one preset stop position of the engine is converted into at least one mapped stop position of the generator.

[0098] For example, the generator controller can obtain at least one preset stop position of the engine from the engine controller. For instance, such as... Figure 4 As shown, the preset shutdown position may include two positions: a second position 302 and a fourth position 305. The generator controller can, based on the mapping relationship between the engine crankshaft position and the generator resolver position, convert the engine crankshaft position corresponding to each preset engine shutdown position into the resolver position that the generator rotor needs to reach, thereby obtaining at least one mapped shutdown position for the generator.

[0099] In one implementation, the mapped stop position of the generator is determined based on the preset stop position of the engine and the mapping relationship. When the crankshaft stops at the preset stop position, the resolver is in the corresponding position in the generator.

[0100] In one implementation, the generator controller can substitute the preset shutdown position of the engine into the mathematical formula based on the pre-established mapping relationship, and directly calculate the corresponding generator resolver position, i.e., the mapped shutdown position of the generator, through mathematical operations.

[0101] For example, regarding such Figure 4 The formula for calculating the corresponding mapped stopping position for the two preset stopping positions shown can be:

[0102] (1)

[0103] (2)

[0104] In formula (1), This indicates the mapped stop position corresponding to the 29th tooth position. This indicates the spin position at the current moment. According to Calculated. This indicates the position of the engine crankshaft with 29 teeth. This indicates the crankshaft position at the current moment. These are preset coefficients. Indicates the current moment.

[0105] In formula (2), This indicates the mapped stop position corresponding to tooth position 59. According to Calculated. This indicates the position of the engine crankshaft with tooth 59.

[0106] In another implementation, the generator controller can create a table mapping the engine crankshaft position to the generator resolver position and store it in the controller's storage unit. When a conversion is needed, the controller searches the table based on the engine's preset stop position to find the corresponding generator resolver position, i.e., the generator's mapped stop position.

[0107] S201212. Based on the resolver position of the generator at the current moment, select the target shutdown position from at least one mapped shutdown position.

[0108] For example, after the generator controller obtains the resolver position at the current moment in real time, it can sort the mapped stop positions according to the distance between each mapped stop position and the resolver position at the current moment.

[0109] The controller can select one of the mapped stopping positions as the target stopping position based on the distance between each mapped stopping position and the current resolver position.

[0110] In one implementation, the controller can select the mapped stop position closest to the resolver position as the target stop position.

[0111] In one implementation, the controller may also take into account the stopping distance and select the mapped stopping position that is greater than the stopping distance and is closest to the resolver position as the target stopping position.

[0112] Optionally, the stopping distance can be 5 teeth.

[0113] In this example, by converting the engine's preset shutdown position into the generator's mapped shutdown position based on the mapping relationship, and by combining the generator's resolver position with the selection of the target shutdown position from the mapped shutdown positions, the optimal shutdown position of the generator is accurately determined, thereby improving the generator's shutdown efficiency.

[0114] In one example, the specific process of selecting a target parking location from at least one mapped parking location in step S201212 above includes:

[0115] S2012121. If the difference between the resolver position of the generator at the current moment and the nearest mapped shutdown position is less than or equal to a first threshold, then the next mapped shutdown position of the nearest mapped shutdown position is determined as the target shutdown position. If the difference between the resolver position of the generator at the current moment and the nearest mapped shutdown position is greater than the first threshold, then the nearest mapped shutdown position is determined as the target shutdown position.

[0116] For example, the generator controller continuously acquires resolver position data of the generator at the current moment via a resolver sensor. The generator controller can determine the nearest mapped stop position to the generator's current resolver position from at least one mapped stop position. The generator controller can calculate the difference between the current resolver position and the nearest mapped stop position.

[0117] If the difference is less than or equal to a preset first threshold, it indicates that the generator's current resolver position is very close to the nearest mapped stop position. In this case, according to the preset control strategy, it is impossible to stop the generator's resolver at that nearest mapped stop position. Therefore, the generator controller can obtain the next mapped stop position from that nearest mapped stop position and use that next mapped stop position as the target stop position.

[0118] Otherwise, if the difference is greater than a preset first threshold, it indicates that the current resolver position of the generator is some distance from the nearest mapped shutdown position. In this case, according to the preset control strategy, the generator can be stopped at the nearest mapped shutdown position. Therefore, the generator controller can use this nearest mapped shutdown position as the target shutdown position.

[0119] In one implementation, the nearest mapped stopping position is the mapped stopping position with the smallest distance from the current resolver position. For example, such as... Figure 4 As shown, the nearest preset stop position corresponding to the crankshaft 303 at the current moment is the second position 302. Correspondingly, the target stop position is the resolver position corresponding to the second position 302.

[0120] In one implementation, the next mapped stop position after the nearest mapped stop position is the mapped stop position with the second smallest distance from the current resolver position. For example, as... Figure 4 As shown, when the nearest preset stop position is the second position 302, the next preset stop position is the fourth position 305.

[0121] In one implementation, the first threshold is a preset value. Typically, this first threshold is determined based on the distance the generator travels from 100 rpm to 0 rpm at 100 rpm. For example, the first threshold could be 5 teeth. Or, for example, the first threshold could be 30 degrees.

[0122] In this example, the target shutdown position is determined by comparing the difference between the generator's current resolver position and the nearest mapped shutdown position with a first threshold. This method achieves accurate determination of the generator's target shutdown position, improves the generator's shutdown accuracy, and thus enhances the vehicle's NVH performance.

[0123] In one example, in step S20122 above, the process of the generator controller controlling the generator to stop after the generator speed decreases to a first preset speed may include:

[0124] S201221. When the difference between the generator's resolver position and the target shutdown position reaches a second threshold, after a first preset time delay, the generator is de-torqueed so that the generator's torque drops to 0 according to a preset torque smoothing curve. The second threshold is less than the first threshold.

[0125] For example, the generator controller monitors the resolver position of the generator in real time and compares it with a determined target shutdown position, calculating the difference between the two. When the difference reaches a preset second threshold, the generator controller can control the generator to de-torque after a first preset time delay.

[0126] During the torque reduction process, the generator controller can make the generator gradually reduce the torque to 0 according to the preset torque smoothing curve, thereby realizing the generator to reduce torque smoothly and orderly.

[0127] In one implementation, the second threshold is a pre-set value used to determine whether the generator's resolver position at the current moment is close to the target shutdown position. If the difference is less than or equal to the second threshold, it indicates that the generator's resolver position is close to the target shutdown position. Otherwise, it indicates that the generator's resolver position is far from the target shutdown position.

[0128] For example, the second threshold can be 2 teeth. For example, the second threshold can be 12 degrees, 10 degrees, etc.

[0129] In one implementation, when the resolver position of the generator approaches the target shutdown position, the generator controller can move the remaining distance by withdrawing the torque, thereby further ensuring that the generator can stop at the target shutdown position.

[0130] In one implementation, the first preset time is a preset waiting duration. For example, the first preset duration can be 0.1 seconds.

[0131] Optionally, within the first preset duration, the generator controller can control the generator based on the previous torque.

[0132] Optionally, the generator controller can switch the control mode of the generator within the first preset time period.

[0133] Optionally, during the first preset duration, the generator controller can release the generator state so that the generator can better adjust the torque at subsequent times.

[0134] In one implementation, torque cancellation means canceling the generator's output torque, so that the generator no longer provides power to the outside world.

[0135] In one implementation, the preset torque smoothing curve is a pre-defined curve. This curve describes the change in generator torque over time. Controlling torque decrease according to this curve can make the generator torque change more smoothly and reduce engine vibration.

[0136] In one implementation, a timer module is integrated within the generator controller. When the difference between the generator's resolver position and the target stop position reaches a second threshold, the generator controller starts the timer and sets the timing period to a first preset time. The timer begins counting, and when the first preset time is reached, the timer generates an interrupt signal to notify the generator controller to perform subsequent torque removal operations.

[0137] In one implementation, the generator controller implements a counter via software programming. When the difference reaches a second threshold, the counter starts counting at a certain clock frequency. When the count value reaches a value corresponding to a first preset time, the generator controller determines that the delay time has ended and performs a torque cancellation operation.

[0138] In one implementation, the generator controller can pre-discrete the torque smoothing curve into a series of correspondences between torque values ​​and time points, and store these correspondences in the generator controller's memory to form a table. During torque reduction, the generator controller looks up the corresponding torque value from the table based on the current time and outputs it as the target torque to the generator's control unit, thereby controlling the generator's torque to decrease according to the preset curve.

[0139] In one implementation, the generator controller can calculate the torque value corresponding to the current time in real time during the torque release process, based on a preset mathematical expression of the torque smoothing curve.

[0140] In this example, when the difference between the generator's resolver position and the target shutdown position reaches a second threshold, the generator is de-torqued according to a preset torque smoothing curve, thus achieving a smooth shutdown of the generator.

[0141] In one example, the method of controlling the generator to reduce its speed in step S2011 above may include:

[0142] S20111. Generate the engine speed sequence based on the generator's current speed and the preset speed drop slope.

[0143] For example, after determining that the generator needs to reduce its speed, the generator controller can obtain a preset speed reduction slope stored internally. The generator can then generate a sequence of engine speeds based on this speed reduction slope and the generator controller's current speed.

[0144] In one implementation, the generator's rotational speed at the current moment is the generator rotor speed. The unit is usually revolutions per minute (r / min), which intuitively reflects the generator's current operating status.

[0145] In one implementation, the preset speed drop slope is a pre-set parameter. It represents the rate of decrease in generator speed per unit time, and the unit can be revolutions per minute per second (r / min / s). This speed drop slope determines how quickly the generator drops from its current speed to the target speed, and has a significant impact on the smoothness and efficiency of the engine shutdown process.

[0146] Optionally, the preset speed drop slope can be a value, and the generator controller can generate a subsequent speed sequence based on this speed drop slope. This speed sequence can include multiple speeds in time sequence.

[0147] Optionally, the preset speed decrease slope can be a sequence. The generator controller can then generate a subsequent speed sequence based on this speed decrease slope sequence. This speed sequence can include multiple speeds in a time sequence.

[0148] In one implementation, the engine speed sequence is a curve with time on the horizontal axis and speed on the vertical axis. It describes the change in engine speed over time as the engine decreases from its current speed according to a preset speed decrease slope to the target speed.

[0149] In one implementation, the preset speed reduction slope can be a large slope, thereby achieving a rapid decrease in speed. For example, it is possible to reduce the speed from 5000 rpm to 100 rpm within 10 seconds.

[0150] S20112. Control the generator to adjust its speed according to the speed sequence in order to reduce the generator speed.

[0151] For example, after the generator controller generates the engine speed sequence, it generates control commands based on the speed at each moment and sends the control commands to the generator so that the generator adjusts its speed accordingly.

[0152] In this example, by generating a speed sequence based on the current speed of the generator and the first preset speed reduction slope, and controlling the generator to adjust its speed according to the speed sequence, the generator can quickly and smoothly reduce its speed.

[0153] In one example, the crankshaft position signal sent by the engine controller to the CAN bus in real time has a 10ms message period. At higher engine speeds, the tooth signal may jump. At very low speeds, the original crankshaft position waveform has uneven intervals, which can easily be misidentified as a missing tooth position, causing the tooth signal to reset to 1 before reaching 60 teeth, resulting in inaccurate tooth signals. Therefore, when mapping the crankshaft position uploaded by the engine controller to the resolver position of the generator controller around 100 rpm, multiple corrections can be performed to minimize position deviations introduced by system delays.

[0154] Following step S201212 above, the process of correcting the mapping relationship includes:

[0155] S201213. After generating the mapping relationship between the crankshaft position of the engine and the resolver position of the generator, continuously collect the crankshaft position of the engine and the resolver position of the generator.

[0156] For example, after generating the mapping relationship between the engine crankshaft position and the generator resolver position, the generator controller can continue to obtain the generator resolver position through the resolver sensor. Also, the generator controller can continue to obtain the engine crankshaft position from the crankshaft sensor through the engine controller.

[0157] In one implementation, the generator controller triggers a data acquisition operation at fixed time intervals, simultaneously reading data from the engine crankshaft position sensor and the generator resolver sensor. For example, this time interval can be 10 milliseconds.

[0158] S201214. Correct the mapping relationship based on the crankshaft position of the engine and the resolver position of the generator.

[0159] For example, after acquiring the engine crankshaft position and generator resolver position each time, the generator controller can recalculate the mapping relationship based on the engine crankshaft position and generator resolver position to correct the mapping relationship.

[0160] In one implementation, the generator controller can determine whether the acquired engine crankshaft position and generator resolver position conform to an existing mapping relationship. If they do, the generator controller can acquire the next data. Otherwise, if they do not conform to the mapping relationship, the generator controller can correct the mapping relationship.

[0161] In one implementation, by modifying the mapping relationship, it can be made to more accurately reflect the actual relationship between the engine crankshaft position and the generator resolver position, thereby improving the control accuracy and stability of the system.

[0162] In one implementation, the generator controller can use the least squares method to correct this mapping relationship. The generator controller can use the actual acquired engine crankshaft position and generator resolver position data pairs as sample points, and use the principle of least squares to fit a more accurate function. This function is the mapping relationship.

[0163] In one implementation, the generator controller can use a neural network to correct this mapping relationship. The generator controller can construct a neural network model, taking the engine crankshaft position as input and the generator resolver position as output. The generator controller can train the neural network using actually acquired data, adjusting parameters such as the neural network's weights and biases to make the neural network's output closer to the actual generator resolver position.

[0164] In one implementation, the generator controller can use an incremental method to correct the mapping relationship. When a deviation is detected between the actual data and the mapping relationship, the generator controller can, instead of directly refitting the entire mapping relationship, fine-tune the key parameters in the mapping relationship based on the magnitude and direction of the deviation.

[0165] For example, if the generator resolver position is found to be larger than the value predicted by the mapping relationship, the correlation coefficient in the mapping relationship is reduced by a certain proportion.

[0166] In this example, by continuously acquiring the engine crankshaft position and generator resolver position, and correcting the mapping relationship between the engine crankshaft position and generator resolver position based on the acquired engine crankshaft position and generator resolver position, the accuracy of the engine and generator position correlation is improved, thereby improving control accuracy.

[0167] In one example, based on the above embodiments, the generator controller can also control the generator using different control modes at different times. These control modes can include at least three types: speed control mode, angle control mode, and torque control mode. The process of the generator controller switching between control modes can include:

[0168] S2013. In response to the shutdown command, switch the generator to speed control mode.

[0169] For example, when the generator controller receives a shutdown command from the domain controller, it enters shutdown mode. Once in shutdown mode, the generator controller needs to quickly reduce the generator speed. At this time, the generator controller can initiate the generator's internal control logic switching process, switching to speed control mode.

[0170] In one implementation, the speed control mode is a control mode for the generator. In this speed control mode, the generator controller can precisely control the generator speed.

[0171] In one implementation, the generator controller has a dedicated mode-switching hardware circuit. When a shutdown command is received, the hardware circuit automatically disconnects the control channel corresponding to the current operating mode and simultaneously connects the control channel for the speed control mode, achieving rapid hardware-level mode switching.

[0172] In one implementation, the generator controller can switch modes by setting a mode switching flag and related control logic in the software program. When a shutdown command is detected, the generator controller can modify the mode flag and, based on the new flag, call the speed control mode algorithm and parameters to achieve software switching of the generator control mode.

[0173] S2014. When the generator speed drops to the first preset speed, switch the generator to angle control mode.

[0174] For example, when the generator speed drops to a first preset speed, the generator is close to stopping. At this point, if the speed control mode is continued, there is a problem that the generator's stopping position cannot be accurately controlled. Therefore, the generator controller can restart the mode switching process and switch to angle control mode when it detects that the generator speed has dropped to the first preset speed.

[0175] In one implementation, under angle control mode, the generator controller can more precisely control the rotation angle of the generator based on the angle information of the resolver position measured by the generator resolver sensor, so that the generator can accurately stop at the target position.

[0176] In one implementation, the generator controller can be configured with a speed threshold detection module in its software. This module can compare the actual generator speed with a first preset speed in real time. When the actual speed is less than or equal to the first preset speed, the generator controller can trigger a mode switching signal. The generator controller can then switch the generator to angle control mode.

[0177] S2015. When the difference between the generator resolver position and the target stop position reaches the second threshold, switch the generator to torque control mode.

[0178] For example, when the generator is operating in angle control mode, the generator controller can acquire the generator's resolver position in real time. The generator controller can calculate the difference between the generator's resolver position and a pre-set target stopping position in real time. When this difference is less than or equal to a second threshold, the generator controller determines that the generator is close to the target stopping position. At this time, in order to ensure that the generator can stop at the target stopping position, the generator controller can switch the operating mode to torque control mode.

[0179] In one implementation, in torque control mode, the generator controller precisely controls the generator's output torque by adjusting the generator's electromagnetic torque or mechanical load, so that the generator can stop smoothly in a predetermined manner, avoiding shocks and vibrations caused by sudden stopping.

[0180] In one implementation, the generator controller calculates the difference between the generator's resolver position and the target stop position in real time during each control cycle and compares it with a second threshold. When the difference is less than or equal to the second threshold, a switch to the torque control mode is immediately triggered. For example, this control cycle can be 10 ms.

[0181] In this example, by switching the generator's operating mode under different conditions, a smooth and precise shutdown of the generator is achieved.

[0182] In one example, to minimize the vibration caused by the impact of residual exhaust gas on cylinder pressure, the domain controller, while receiving the generator speed signal on the CAN bus in real time, will, after a second preset time delay, stop sending the auxiliary shutdown status signal when it detects that the generator speed is lower than a second preset speed. Simultaneously, the generator controller can exit the shutdown mode and shut down the high-voltage power supply to the generator based on the exit command sent by the domain controller.

[0183] In one implementation, the auxiliary shutdown status signal can be continuously sent by the generator controller to the domain controller after the generator controller enters the shutdown mode.

[0184] This process may include:

[0185] S202. In response to the exit command sent by the domain controller, control the generator to exit the shutdown mode. The exit command is generated when the generator speed is less than a second preset speed.

[0186] For example, when the generator controller receives an exit command from the domain controller, it can immediately trigger an internally preset exit shutdown mode process.

[0187] In one implementation, the generator controller first verifies the validity of the exit command. After confirming that the command is correct, it begins to control the generator to gradually exit the shutdown mode according to the predetermined logic and parameters.

[0188] In one implementation, the exit command is a specific signal generated by the domain controller and sent to the generator controller. This signal carries a command to exit the shutdown mode of the generator. This signal is typically transmitted in the form of an electrical signal or a digital communication protocol.

[0189] In one implementation, exiting the shutdown mode means that the generator exits the stopped state. Afterwards, the generator controller can generate electricity normally or perform other tasks.

[0190] In one implementation, the generator controller has a dedicated interrupt handling circuit. When it receives an exit command from the domain controller, it generates a hardware interrupt signal. The controller immediately suspends the currently executing task and executes the interrupt service routine, controlling the generator to exit the shutdown mode according to a preset process.

[0191] In one implementation, the generator controller periodically polls the interface communicating with the domain controller via a software program to check for new instructions. When an exit instruction is detected, the software program calls the corresponding exit shutdown mode handling function according to the instruction content, gradually completing the generator's state transition.

[0192] In one implementation, the domain controller can acquire the generator speed uploaded by the generator controller in real time. The domain controller can generate an exit command when it detects that the generator speed is less than or equal to a second preset speed.

[0193] In one implementation, the second preset speed is a pre-set speed threshold. This second preset speed setting takes into account the generator's safe operating range and the stability of the shutdown process, ensuring that the operation to exit the shutdown mode is triggered at the appropriate time.

[0194] For example, the second preset speed can be 10 rpm.

[0195] In one example, the specific execution process of the generator controller exiting the shutdown mode may include:

[0196] S2021. After delaying the generator by a second preset time, the shutdown ends.

[0197] For example, when the generator controller receives the exit command, the generator controller can perform the operation to end the shutdown after a second preset time delay, so that the generator completely exits the shutdown mode.

[0198] In one implementation, the second preset time is a time value preset based on factors such as the mechanical characteristics of the generator, the system response time, and safety requirements. For example, the second preset time can be 0.5s.

[0199] In one implementation, the setting of the second preset time can ensure that after the exit command is issued, the generator has enough time to adjust and stabilize its internal state, thus avoiding system instability or damage caused by sudden shutdown.

[0200] In one implementation, ending the shutdown means that the generator has exited the shutdown state, thereby shutting down the high-voltage power supply.

[0201] In one implementation, the generator controller integrates a high-precision timer module. Upon receiving an exit command, the controller configures the timer's timing and operating mode via software and starts the timer. When the timer reaches a second preset time, an interrupt signal is generated, and the controller responds to the interrupt by executing the shutdown operation.

[0202] In one implementation, the generator controller can utilize an external, independent clock source device, such as a high-precision crystal oscillator or clock chip, to provide a timing reference. The controller reads the timing information from the external clock source and combines it with a software algorithm to implement a second preset time delay. When the set time is reached, the generator is shut down.

[0203] In this example, by obtaining the exit command generated by the domain controller when the generator speed is less than or equal to the second preset speed, and controlling the generator to end the shutdown after a second preset time delay, the generator can safely and smoothly exit the shutdown mode.

[0204] Based on the above embodiments, in execution Figure 2 Prior to the illustrated embodiment, the following steps may also be included:

[0205] The domain controller can continuously send shutdown commands to the CAN bus when the engine needs to be stopped, based on the vehicle's operating conditions. These shutdown commands instruct the generator to perform auxiliary shutdown operations.

[0206] The engine controller transmits the crankshaft position in real time via the CAN bus. Upon receiving a stop command from the domain controller, the engine controller can immediately control the engine to perform actions such as cutting off fuel supply.

[0207] Upon receiving a shutdown command, the generator controller can immediately switch its operating mode to shutdown mode, entering auxiliary shutdown status. Furthermore, the generator controller can continuously transmit generator speed and shutdown status information to the CAN bus.

[0208] Figure 5 This is a flowchart illustrating the range-extended vehicle engine assisted shutdown method provided by the present invention. Figures 1 to 4 Based on the illustrated embodiment, during a single shutdown assistance operation, the vehicle's execution process, based on the domain controller, engine controller, and generator controller, may include:

[0209] S501, the domain controller starts and continuously sends shutdown commands to the CAN bus.

[0210] S502: The engine controller sends crankshaft position signals to the CAN bus in real time and immediately performs actions such as cutting off fuel upon receiving a stop command. Similarly, the generator controller sends generator speed signals to the CAN bus in real time and switches to stop mode upon receiving a stop command.

[0211] S503. In speed control mode, the generator controller takes the generator speed as the control target and quickly lowers the generator speed to the first preset speed according to the preset speed reduction slope.

[0212] S504. When the generator speed is near the first preset speed, the generator controller maps the real-time received crankshaft position to the resolver position and collects and corrects it multiple times.

[0213] S505: The generator controller enters angle control mode, using the resolver position as the control target to control the generator to rotate continuously. It receives the current resolver position in real time, calculates the difference between the current position and the target stopping position, and performs closed-loop control of the generator.

[0214] S506, The generator controller determines the target shutdown location for this shutdown.

[0215] For example, each revolution of the engine may include two preset stopping positions. These two preset stopping positions may correspond to tooth 29 and tooth 59, respectively. The generator controller can determine the corresponding mapping target position on the generator based on these two preset stopping positions.

[0216] If, upon entering angle control mode, the generator resolver position differs from the nearest mapped target position within a first threshold, then the target shutdown position for this shutdown is set as the next mapped shutdown position. If the generator resolver position differs from the nearest mapped target position beyond the first threshold, then the target shutdown position for this shutdown is set as the nearest mapped shutdown position.

[0217] S507: The generator controller continuously controls the generator rotation using angle control. When the resolver position differs from the target stop position by less than a second threshold, it enters torque control mode after a first delay and quickly reduces the torque to 0 according to a preset torque smoothing curve.

[0218] The S508 domain controller receives the generator speed signal from the CAN bus in real time. When the generator speed is detected to be lower than a second preset speed, the transmission of shutdown status information is stopped after a second delay.

[0219] S509. The generator controller exits the shutdown state according to the domain controller's exit command and simultaneously shuts off the generator's high-voltage power supply.

[0220] In this example, the domain controller controls the generator controller and engine controller, thereby enabling the execution of the domain controller's stop and exit commands. This improves the accuracy of the generator's stop position and enhances the vehicle's NVH performance.

[0221] Figure 6 This is a schematic diagram of the structure of the range extender vehicle engine auxiliary shutdown device provided by the present invention, as shown below. Figure 6 As shown, the range extender vehicle engine auxiliary shutdown device 600 provided in this embodiment, applied to the generator controller, includes:

[0222] The shutdown module 601 is used to respond to a shutdown command sent by the domain controller and control the generator to enter a shutdown mode. The shutdown mode includes: controlling the generator to reduce its speed, and when the generator speed decreases to a first preset speed, generating a mapping relationship between the engine crankshaft position and the generator resolver position. Based on the generator's current resolver position and the mapping relationship, the module controls the generator to rotate, so that the generator drives the engine to complete the shutdown at a preset shutdown position.

[0223] In one example, the shutdown module 601 is used for:

[0224] The target shutdown position of the generator is determined based on the mapping relationship, the current resolver position of the generator, and at least one preset shutdown position of the engine.

[0225] Based on the resolver position of the generator and the target shutdown position, the generator is controlled to rotate so that the generator drives the engine to complete the shutdown at the preset shutdown position.

[0226] In one example, the shutdown module 601 is used for:

[0227] Based on the mapping relationship, at least one preset stop position of the engine is converted into at least one mapped stop position of the generator.

[0228] Based on the generator's resolver position at the current moment, select the target shutdown position from at least one mapped shutdown position.

[0229] In one example, the shutdown module 601 is used for:

[0230] If the difference between the generator's current resolver position and the nearest mapped shutdown position is less than or equal to the first threshold, then the next mapped shutdown position of the nearest mapped shutdown position is determined as the target shutdown position.

[0231] If the difference between the generator's current resolver position and the nearest mapped shutdown position is greater than a first threshold, then the nearest mapped shutdown position is determined as the target shutdown position.

[0232] In one example, the shutdown module 601 is used for:

[0233] When the difference between the generator's resolver position and the target shutdown position reaches a second threshold, after a first preset time delay, the generator is de-torqueed so that the generator's torque drops to 0 according to a preset torque smoothing curve; wherein the second threshold is less than the first threshold.

[0234] In one example, the shutdown module 601 is used for:

[0235] The engine speed sequence is generated based on the generator's current speed and a preset speed drop slope.

[0236] The generator is controlled to adjust its speed according to a speed sequence in order to reduce the generator speed.

[0237] In one example, the shutdown module 601 is used for:

[0238] After generating the mapping relationship between the crankshaft position of the engine and the resolver position of the generator, the crankshaft position of the engine and the resolver position of the generator are continuously collected.

[0239] The mapping relationship is corrected based on the crankshaft position of the engine and the resolver position of the generator.

[0240] In one example, the shutdown module 601 is used for:

[0241] In response to a shutdown command, the generator is switched to speed control mode.

[0242] When the generator speed drops to the first preset speed, switch the generator to angle control mode.

[0243] When the difference between the generator's resolver position and the target stop position reaches the second threshold, the generator is switched to torque control mode.

[0244] In one example, exit module 602 is used for:

[0245] In response to the exit command sent by the domain controller, the generator is controlled to exit the shutdown mode.

[0246] Exiting the shutdown mode includes: controlling the generator to delay for a second preset time before ending the shutdown.

[0247] The exit command is generated when the generator speed is less than the second preset speed.

[0248] The range extender vehicle engine auxiliary shutdown device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0249] Figure 7 This is a schematic diagram of the generator controller provided by the present invention. Figure 7 As shown, the generator controller 102 provided in this embodiment includes at least one processor 701 and a memory 702. Optionally, the generator controller 102 further includes a communication component 703. The processor 701, memory 702, and communication component 703 are connected via a bus 704.

[0250] In a specific implementation, at least one processor 701 executes computer execution instructions stored in memory 702, causing at least one processor 701 to perform the above-described method.

[0251] The specific implementation process of processor 701 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0252] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0253] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0254] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0255] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0256] The present invention also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0257] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory, electrically erasable programmable read-only memory, erasable programmable read-only memory, programmable read-only memory, read-only memory, magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0258] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an application-specific integrated circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0259] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0260] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0261] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0262] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0263] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0264] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. A method for assisted engine shutdown in a range-extended vehicle, characterized in that, The method, applied to a generator controller, includes: In response to a shutdown command sent by the domain controller, the generator is controlled to enter shutdown mode; The shutdown mode includes: controlling the generator to reduce its speed, and when the generator speed is reduced to a first preset speed, generating a mapping relationship between the crankshaft position of the engine and the resolver position of the generator; and controlling the generator to rotate according to the resolver position of the generator at the current moment and the mapping relationship, so that the generator drives the engine to complete the shutdown at the preset shutdown position.

2. The method according to claim 1, characterized in that, The step of controlling the generator to rotate based on the generator's current resolver position and the mapping relationship, so that the generator drives the engine to stop at a preset stopping position, includes: Based on the mapping relationship, the current resolver position of the generator, and at least one preset shutdown position of the engine, the target shutdown position of the generator is determined; Based on the resolver position of the generator and the target shutdown position, the generator is controlled to rotate so that the generator drives the engine to stop at the preset shutdown position.

3. The method according to claim 2, characterized in that, Determining the target shutdown position of the generator based on the mapping relationship, the resolver position of the generator at the current moment, and at least one preset shutdown position of the engine includes: According to the mapping relationship, at least one preset stop position of the engine is converted into at least one mapped stop position of the generator; Based on the resolver position of the generator at the current moment, a target shutdown position is selected from at least one of the mapped shutdown positions.

4. The method according to claim 3, characterized in that, The step of selecting a target shutdown position from at least one of the mapped shutdown positions based on the resolver position of the generator at the current moment includes: If the difference between the current resolver position of the generator and the nearest mapped shutdown position is less than or equal to a first threshold, then the next mapped shutdown position after the nearest mapped shutdown position is determined as the target shutdown position. If the difference between the current resolver position of the generator and the nearest mapped shutdown position is greater than a first threshold, then the nearest mapped shutdown position is determined as the target shutdown position.

5. The method according to claim 2, characterized in that, The step of controlling the generator to rotate based on the resolver position and the target stopping position, so that the generator drives the engine to stop at the preset stopping position, includes: When the difference between the resolver position of the generator and the nearest target shutdown position reaches a second threshold, after a first preset time, the generator is de-torqueed so that the torque of the generator drops to 0 according to a preset torque smoothing curve; wherein the second threshold is less than the first threshold.

6. The method according to any one of claims 1-5, characterized in that, The control of the generator to reduce its speed includes: The engine speed sequence is generated based on the generator's current speed and a preset speed decrease slope; The generator is controlled to adjust its speed according to the speed sequence in order to reduce the speed of the generator.

7. The method according to any one of claims 1-5, characterized in that, The method further includes: After generating the mapping relationship between the crankshaft position of the engine and the resolver position of the generator, the crankshaft position of the engine and the resolver position of the generator are continuously collected. The mapping relationship is corrected based on the crankshaft position of the engine and the resolver position of the generator.

8. The method according to any one of claims 1-5, characterized in that, The method further includes: In response to a shutdown command, the generator is switched to speed control mode; When the speed of the generator decreases to the first preset speed, the generator is switched to angle control mode; When the difference between the resolver position and the target stop position of the generator reaches a second threshold, the generator is switched to torque control mode.

9. The method according to any one of claims 1-5, characterized in that, The method further includes: In response to an exit command sent by the domain controller, the generator is controlled to exit the shutdown mode; The exit from the shutdown mode includes: controlling the generator to delay for a second preset time before ending the shutdown; The exit command is generated when the generator speed is less than a second preset speed.

10. An auxiliary engine shutdown device for a range-extended vehicle, characterized in that, The device includes: The control module is used to respond to the shutdown command sent by the domain controller and control the generator to enter the shutdown mode; The shutdown mode includes: controlling the generator to reduce its speed, and when the generator speed is reduced to a first preset speed, generating a mapping relationship between the crankshaft position of the engine and the resolver position of the generator; and controlling the generator to rotate according to the resolver position of the generator at the current moment and the mapping relationship, so that the generator drives the engine to complete the shutdown at the preset shutdown position.

11. A generator controller, characterized in that, include: Memory, processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory, causing the processor to perform the method as described in any one of claims 1-9.

12. A car, characterized in that, include: Domain controller, torque limiter, engine, generator, generator controller as described in claim 11; The generator and the engine are coaxially connected via the torque limiter; the generator controller is communicatively connected to the domain controller.

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