Generator rotating speed control method and device, automobile and storage medium
By combining PI-modulated torque with torque compensation and feedforward control based on the difference between engine coolant temperature and crankshaft angle, the problem of large fluctuations in traditional generator speed control is solved, achieving precise control and improving the NVH performance and emission performance of electric vehicles.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-21
- Publication Date
- 2026-04-21
AI Technical Summary
Traditional generator speed control methods rely on PI regulation, which leads to large fluctuations in generator speed and makes precise control impossible.
The PI controller obtains the PI-modulated torque of the target speed difference, and combines it with torque compensation and feedforward control based on the engine's real-time water temperature and crankshaft angle difference to determine the generator's target torque, thus achieving closed-loop torque control.
It reduces generator speed fluctuations, improves the NVH performance of electric vehicles, reduces emissions during the start-up phase, and lowers catalytic converter costs.
Smart Images
Figure CN121893935A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of automotive technology, and in particular to a generator speed control method, device, automobile, and storage medium. Background Technology
[0002] For automobiles, such as hybrid and range-extended electric vehicles, when the engine enters certain operating conditions, it may lead to poor combustion stability and large fluctuations in engine torque, which in turn leads to large fluctuations in generator speed. Currently, most manufacturers control the fluctuations in generator speed through generator controllers.
[0003] The inventors discovered that in traditional solutions, the generator speed control relies solely on PI regulation, resulting in large fluctuations in generator speed and failing to achieve precise control of generator speed fluctuations. Summary of the Invention
[0004] This application provides a generator speed control method, device, electric vehicle, and storage medium to solve the technical problem that traditional solutions easily lead to large fluctuations in generator speed.
[0005] In a first aspect, a generator speed control method is provided, the method comprising: After the engine enters the preset operating condition, the PI controller obtains the PI modulation torque corresponding to the target speed difference, where the target speed difference is the difference between the engine target speed and the engine real-time speed. The water temperature compensation torque corresponding to the engine real-time water temperature is obtained from the pre-calibrated torque compensation relationship, and / or the feedforward torque corresponding to the engine crankshaft angle difference is obtained from the pre-calibrated feedforward torque relationship. The generator target torque is determined based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque. The generator is controlled to operate in closed-loop mode at the target torque of the generator.
[0006] Further, determining the generator target torque based on the PI-modulated torque, the water temperature compensation torque, and / or the feedforward torque includes: The PI modulation torque is added to the water temperature compensation torque to obtain the generator target torque; or; The PI modulation torque is added to the feedforward torque to obtain the generator target torque; or; The PI modulation torque, the water temperature compensation torque, and the feedforward torque are added together to obtain the generator target torque.
[0007] Furthermore, the engine entering the preset operating condition includes the engine entering the catalytic converter heating stage.
[0008] Furthermore, the feedforward torque relationship characterizes the correspondence between the crankshaft angle difference of different calibrated engines and the calibrated feedforward torque. Each calibrated engine crankshaft angle difference is the crankshaft angle difference between preset time intervals, where the preset time interval is ≤1ms.
[0009] Furthermore, before obtaining the water temperature compensation torque corresponding to the real-time engine water temperature and / or the feedforward torque corresponding to the engine crankshaft angle difference, the method further includes: The target engine torque is determined based on the target engine speed and the target power output from the vehicle controller. Control the engine to operate at the target engine torque.
[0010] Furthermore, controlling the engine to operate at the engine target torque includes: The engine is controlled to operate in torque closed-loop mode at the engine target torque.
[0011] Secondly, a generator speed control device is provided, comprising: The first acquisition module is used to acquire the PI modulation torque corresponding to the target speed difference through the PI controller after the engine enters the preset operating condition. The target speed difference is the difference between the engine target speed and the engine real-time speed. The second acquisition module is used to obtain the water temperature compensation torque corresponding to the real-time water temperature of the engine from a pre-calibrated torque compensation relationship, and / or obtain the feedforward torque corresponding to the crankshaft angle difference of the engine from a pre-calibrated feedforward torque relationship. The determination module is used to determine the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque; A control module is used to control the generator to operate in torque closed-loop mode at the generator's target torque.
[0012] Thirdly, an electric vehicle is provided, the electric vehicle including an engine, a generator, and a generator controller: After the engine enters the preset operating condition, the generator controller obtains the PI modulation torque corresponding to the target speed difference through the PI controller. The target speed difference is the difference between the engine target speed and the engine real-time speed. The generator controller obtains the water temperature compensation torque corresponding to the real-time engine water temperature from a pre-calibrated torque compensation relationship, and / or obtains the feedforward torque corresponding to the engine crankshaft angle difference from a pre-calibrated feedforward torque relationship. The generator controller determines the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque; The generator controller controls the generator to operate in torque closed-loop mode at the generator target torque.
[0013] Furthermore, the generator controller determines the target torque of the generator based on the PI-modulated torque, the water temperature compensation torque, and / or the feedforward torque, including: The generator controller adds the PI modulation torque to the water temperature compensation torque to obtain the generator target torque; or; The generator controller adds the PI-modulated torque to the feedforward torque to obtain the generator target torque; or; The generator controller adds the PI modulation torque, the water temperature compensation torque, and the feedforward torque to obtain the generator target torque.
[0014] Furthermore, the engine entering the preset operating condition includes the engine entering the catalytic converter heating stage.
[0015] Furthermore, the feedforward torque relationship characterizes the correspondence between the crankshaft angle difference of different calibrated engines and the calibrated feedforward torque. Each calibrated engine crankshaft angle difference is the crankshaft angle difference between preset time intervals, where the preset time interval is ≤1ms.
[0016] Furthermore, the electric vehicle also includes an engine controller and a vehicle controller; Before obtaining the water temperature compensation torque corresponding to the real-time engine water temperature and / or the feedforward torque corresponding to the engine crankshaft angle difference, the engine controller determines the engine target torque based on the engine target speed and the target power issued by the vehicle controller. The engine controller controls the engine to operate at the engine target torque.
[0017] Furthermore, the engine controller controls the engine to operate at the target engine torque, including: The engine controller controls the engine to operate at the engine target torque in torque closed-loop mode.
[0018] Fourthly, a computer-readable storage medium is provided, the computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the generator speed control method as described in any of the preceding claims.
[0019] One of the solutions provided above adds torque compensation control based on engine coolant temperature, which can compensate for engine torque differences under different coolant temperatures in advance, and / or adds torque feedforward control based on engine crankshaft angle difference, which can compensate for engine torque differences under different engine crankshaft positions in advance. Therefore, it can reduce the PI adjustment amount in generator speed control, thereby reducing speed fluctuations, achieving precise control of generator speed, reducing generator speed fluctuations, and improving the NVH performance of electric vehicles. Attached Figure Description
[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application 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.
[0021] Figure 1 This is a schematic flowchart of a generator speed control method according to an embodiment of this application; Figure 2 This is another schematic flowchart of a generator speed control method according to one embodiment of this application; Figure 3 This is a schematic diagram of the structure of an electric vehicle according to one embodiment of this application; Figure 4 This is a schematic diagram of a generator speed control device according to one embodiment of this application; Figure 5 This is a schematic diagram of a generator controller according to one embodiment of this application. Detailed Implementation
[0022] 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, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0023] This application provides a generator speed control method, device, electric vehicle, and storage medium. The above solution can be applied to various types of electric vehicles, including, but not limited to, range-extended electric vehicles, non-range-extended electric vehicles, or future new electric vehicles; no specific limitation is made. In some operating conditions of electric vehicles, the combustion stability of the engine may deteriorate, causing large fluctuations in engine torque, which ultimately leads to large fluctuations in the generator speed. This situation can cause other problems with the electric vehicle, such as reduced NVH performance. Therefore, this application provides the above solution, mainly addressing the problem of large generator speed fluctuations; the following describes several embodiments in detail.
[0024] In one embodiment, combined with Figure 1 and Figure 3 As shown, a generator speed control method is provided, the method comprising the following steps: S10: After the engine enters the preset operating condition, the PI controller obtains the PI modulation torque corresponding to the target speed difference, wherein the target speed difference is the difference between the engine target speed and the engine real-time speed. S20: Obtain the water temperature compensation torque corresponding to the real-time engine water temperature from the pre-calibrated torque compensation relationship, and / or obtain the feedforward torque corresponding to the engine crankshaft angle difference from the pre-calibrated feedforward torque relationship; In step S10, as Figure 2 As shown, after the electric vehicle's engine enters the preset operating condition, the generator controller will obtain the PI modulation torque Tor_PI corresponding to the target speed difference dSpeed through the PI controller. The target speed difference dSpeed is the difference between the engine target speed Speed_goal and the engine real-time speed Speed_motor. For example, the engine target speed Speed_goal can be the engine target speed issued by the vehicle controller based on the current operating condition requirements, and the engine real-time speed Speed_motor can be obtained by the generator controller through the motor resolver signal processing of the engine.
[0025] It should be understood that the PI controller is a regulator used in electric vehicles to adjust the output torque. The target speed difference dSpee represents the difference between the actual output speed and the setpoint, i.e., the difference between the engine's real-time speed Speed_motor and the engine's target speed Speed_goal. By inputting this target speed difference dSpee into the PI controller of the electric vehicle, the PI-modulated torque corresponding to the current target speed difference dSpee can be obtained. The PI regulator is a linear controller that outputs power through both proportional and integral regulation methods to make the output close to the setpoint. The PI regulator consists of two parts: proportional (P) and integral (I), used for rapid response and eliminating steady-state error, respectively. The function of proportional regulation (P) is to adjust the control output according to the proportion of the deviation signal to reduce output deviation.
[0026] In step S20, such as Figure 2 As shown, after the engine enters the preset operating condition, the generator controller will also obtain the water temperature compensation torque Tor_tmot corresponding to the real-time engine water temperature tmot from the pre-calibrated torque compensation relationship, and / or, obtain the feedforward torque Tor_Ang corresponding to the engine crankshaft angle difference dAng from the pre-calibrated feedforward torque relationship. That is, after the engine enters the preset operating condition, the following three different processes can be performed: The first method involves the generator controller obtaining the water temperature compensation torque Tor_tmot corresponding to the real-time engine water temperature tmot from a pre-calibrated torque compensation relationship. The real-time engine water temperature can be read by the generator controller via the vehicle's CAN bus; specifically, the engine controller can send a water temperature CAN signal to the generator controller.
[0027] The second method involves the generator controller obtaining the feedforward torque Tor_Ang corresponding to the engine crankshaft angle difference dAng from a pre-calibrated feedforward torque relationship. Specifically, the generator controller acquires the engine crankshaft signal and maps it to the motor resolver signal to obtain the engine crankshaft angle Ang. Based on the angle difference dAng within a preset time interval (e.g., 1 ms, depending on the time interval used when calibrating the feedforward torque relationship), the generator controller obtains the feedforward torque corresponding to the engine crankshaft angle difference from the pre-calibrated feedforward torque relationship.
[0028] The third method involves the generator controller obtaining the water temperature compensation torque Tor_tmot corresponding to the real-time engine water temperature tmot from a pre-calibrated torque compensation relationship, and obtaining the feedforward torque Tor_Ang corresponding to the engine crankshaft angle difference dAng from a pre-calibrated feedforward torque relationship.
[0029] The torque compensation relationship CUR_tmot represents the correspondence between different calibrated engine real-time water temperatures and calibrated water temperature compensation torque. This torque compensation relationship calibrates the difference in engine friction torque under different engine real-time water temperatures, so as to accurately compensate for the engine output torque under different engine water temperatures.
[0030] The feedforward torque relationship CUR_dAng characterizes the correspondence between different calibrated engine crankshaft angle differences and calibrated feedforward torque. For example, in one embodiment, each calibrated engine crankshaft angle difference is a crankshaft angle difference between preset time intervals, where the preset time interval is ≤1ms. That is, the time interval for the calibrated engine crankshaft angle difference can be 1ms or other durations, determined empirically, and is not specifically limited. This feedforward torque relationship CUR_dAng calibrates the feedforward torque under different engine crankshaft angle differences, thereby reducing the adjustment amount of the PI (Input / Output) converter.
[0031] The above relationships need to be obtained through pre-calibration experiments. It is worth noting that the torque compensation relationship and / or the feedforward torque relationship can be characterized or stored in various forms in practical applications for use in subsequent electric vehicles. No specific limitation is made, such as tabular form or curve form.
[0032] For example, as shown in Table 1 below, Table 1 is an example of a torque compensation relationship: Table 1 In the examples in Table 1, tmot represents the calibrated real-time engine coolant temperature, and Tor_tmot represents the calibrated coolant temperature compensation torque. There are a total of 13 calibrated coolant temperature compensation torques. It should be noted that the specific examples in Table 1 are for illustrative purposes only and are not intended to limit the specific application. For instance, if the obtained real-time engine coolant temperature represents a value of 5, then the torque Tw11 corresponding to 5 can be found in Table 1 as the coolant temperature compensation torque, and so on. Specific examples are not detailed here. For example, as shown in Table 2 below, Table 2 is an example of a feedforward torque relationship: Table 2 In the examples in Table 2, dAng represents the crankshaft angle difference of the calibrated engine, and Tor_Ang represents the calibration feedforward calibration torque, with a total of n possibilities. For example, combined with... Figure 2 As shown, for example, if the obtained engine crankshaft angle difference is K1, (Ang_k-Ang_k-1) can be found from Table 2 to find the torque Tk1 corresponding to the engine crankshaft angle difference K1 as the feedforward torque, and so on. The specific details will not be explained one by one.
[0033] In summary, after the engine enters the preset operating condition, the generator controller can obtain the water temperature compensation torque corresponding to the real-time water temperature of the engine from the pre-calibrated torque compensation relationship, and / or obtain the feedforward torque corresponding to the crankshaft angle difference of the engine from the pre-calibrated feedforward torque relationship. S20: Determine the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque; S30: Control the generator to operate in torque closed-loop mode at the generator target torque.
[0034] In steps S20-S30, after the generator controller obtains the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang, the generator controller determines the generator target torque Tor_motor based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang, so as to control the generator to operate at the generator target torque Tor_motor. That is, the generator controller determines the generator target torque Tor_motor based on the PI modulation torque Tor_PI and the water temperature compensation torque Tor_tmot; or the generator controller determines the generator target torque Tor_motor based on the PI modulation torque Tor_PI and the feedforward torque Tor_Ang; or the generator target torque Tor_motor is determined based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and the feedforward torque Tor_Ang; finally, the generator is controlled to operate at the generator target torque in torque closed-loop mode.
[0035] In this embodiment, a generator speed control method is provided. In this method, the generator controller obtains the PI modulation torque Tor_PI corresponding to the target speed difference through a PI controller, and obtains the water temperature compensation torque Tor_tmot corresponding to the real-time engine water temperature from a pre-calibrated torque compensation relationship, and / or obtains the feedforward torque Tor_Ang corresponding to the engine crankshaft angle difference from a pre-calibrated feedforward torque relationship. Finally, the generator controller determines the generator target torque Tor_motor based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang to control the generator.
[0036] In other words, this embodiment adds torque compensation control based on engine coolant temperature, which can compensate for the difference in engine torque under different coolant temperatures in advance, and / or adds torque feedforward control based on engine crankshaft angle difference, which can compensate for the difference in engine torque under different engine crankshaft positions in advance. Therefore, it can reduce the PI adjustment amount in generator speed control, thereby reducing speed fluctuations, achieving precise control of generator speed, reducing generator speed fluctuations, and improving the NVH performance of electric vehicles.
[0037] It is also worth noting that, through the precise adjustment of the embodiments of this application, the engine can adopt multiple ignition angle reduction or lean combustion schemes without causing unstable speed, thus reducing pollutant emissions during the ignition phase and ultimately achieving the goal of reducing catalyst costs. It should be noted that, as mentioned in the foregoing embodiments, the generator controller determines the generator target torque Tor_motor based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang. Specifically, in one embodiment, step S20, determining the generator target torque Tor_motor based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang, includes the following steps: The PI modulation torque Tor_PI is added to the water temperature compensation torque Tor_tmot to obtain the generator target torque Tor_motor; or; The PI modulation torque Tor_PI is added to the feedforward torque Tor_Ang to obtain the generator target torque Tor_motor; or; The PI modulation torque Tor_PI, the water temperature compensation torque, and the feedforward torque Tor_Ang are added together to obtain the generator target torque Tor_motor.
[0038] Please see as follows Figure 2 As shown, Figure 2 This diagram illustrates the process of adding the PI-modulated torque Tor_PI, the water temperature compensation torque, and the feedforward torque Tor_Ang to obtain the generator target torque Tor_motor. For details, please refer to... Figure 2 As described above, the acquisition process of each signal will not be repeated here.
[0039] In this embodiment, corresponding to the aforementioned embodiment, three specific methods are provided to obtain the generator target torque Tor_motor. These methods are directly added together for compensation, thereby achieving precise control of the generator speed, reducing generator speed fluctuations, improving the NVH performance of the electric vehicle, and ensuring the feasibility of the solution. It is worth noting that in other embodiments, in the process of determining the generator target torque Tor_motor based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang, in addition to directly adding the PI modulation torque Tor_PI, the water temperature compensation torque, and / or the feedforward torque Tor_Ang for compensation, other adjustments and supplements can also be made, such as adding other compensation torques such as injection timing torque compensation. The specific method is not limited.
[0040] In one embodiment, the engine entering the preset operating condition includes the engine entering the catalytic converter heating stage.
[0041] It should be noted that the generator speed control method provided in this application is applicable to various operating conditions of electric vehicles to solve the problem of large generator speed fluctuations caused by the above-mentioned operating conditions. In one such case, the engine entering the preset operating condition includes the engine entering the catalytic converter heating stage. For electric vehicles, after entering the catalytic converter heating condition, the catalytic converter often needs to be heated quickly by retarding the ignition angle (also known as de-ignition). However, de-ignition leads to poor engine combustion stability, resulting in large engine torque fluctuations, which in turn affects the generator speed. Therefore, in this embodiment, the generator speed control method provided in this application adds torque compensation control based on engine coolant temperature, which can compensate for engine torque differences at different coolant temperatures in advance, and / or adds torque feedforward control based on engine crankshaft angle differences, which can compensate for engine torque differences at different engine crankshaft positions in advance. Therefore, after the electric vehicle enters the catalytic converter heating condition, the PI adjustment amount in the generator speed control can be reduced, thereby reducing speed fluctuations. Precise control of the generator speed is achieved after entering the catalytic converter heating condition, reducing generator speed fluctuations caused by catalytic converter heating, thus improving the NVH performance of the electric vehicle.
[0042] It is also worth noting that, in some embodiments, the electric vehicle can be a range-extended electric vehicle. Under catalytic converter heating conditions, the range extender speed fluctuation of the range-extended electric vehicle is also mainly caused by the torque fluctuation of the engine. This embodiment can also reduce the speed fluctuation of the range extender and improve the NVH performance of the range-extended electric vehicle.
[0043] In one embodiment, before step S20, that is, before obtaining the water temperature compensation torque corresponding to the real-time engine water temperature and / or the feedforward torque corresponding to the engine crankshaft angle difference, the method further includes the following steps: S101: Determine the engine target torque based on the engine target speed and the target power output from the vehicle controller; S102: Control the engine to operate at the target engine torque.
[0044] In one embodiment, as an example, controlling the engine to operate at the engine target torque may refer to controlling the engine to operate at the engine target torque in torque closed-loop mode; or operating in other modes, without being specifically limited.
[0045] In this embodiment, under certain driving conditions, the vehicle controller will send the engine target speed (Speed_goal) and target power (P) to ensure the engine operates according to these parameters. For example, taking the catalytic converter heating stage as an example, after an electric vehicle enters this stage, the engine controller receives the target power (P) and target speed (Speed_goal) from the vehicle controller. If it is a range-extended electric vehicle entering the catalytic converter heating stage, the range extender controller receives the target power (P) and target speed (Speed_goal) from the vehicle controller. The engine controller then calculates the engine target torque (Tor_engine) based on the target power (P) and target speed (Speed_goal) and operates using this target torque (Tor_engine) in torque closed-loop mode.
[0046] In this embodiment, the engine operation control processing is limited to certain preset operating conditions, such as the engine operation control processing after entering the catalyst heating stage. Specifically, after entering the catalyst heating stage, the vehicle controller can issue a target power P and a target speed Speed_goal according to the heating requirements, heating status, and other needs. This allows the engine to operate in torque closed-loop mode or other modes with the engine target torque Tor_engine, confirming the catalyst heating condition and thus meeting optimal emissions. Furthermore, by controlling the engine with the engine target torque in torque closed-loop mode, the fluctuation of engine output torque can be reduced before the generator speed control is implemented, thus reducing the PI adjustment amount.
[0047] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.
[0048] The above embodiments describe a generator speed control method provided by this application from a methodological perspective. Correspondingly, this application also provides an electric vehicle, which includes either a range-extended electric vehicle or a non-range-extended electric vehicle, without specific limitations. Figure 3 As shown, an electric vehicle includes an engine, a generator, and a generator controller, wherein: After the engine enters the preset operating condition, the generator controller obtains the PI modulation torque corresponding to the target speed difference through the PI controller. The target speed difference is the difference between the engine target speed and the engine real-time speed. The generator controller obtains the water temperature compensation torque corresponding to the real-time engine water temperature from a pre-calibrated torque compensation relationship, and / or obtains the feedforward torque corresponding to the engine crankshaft angle difference from a pre-calibrated feedforward torque relationship. The generator controller determines the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque; The generator controller controls the generator to operate in torque closed-loop mode at the generator target torque.
[0049] In this embodiment, an electric vehicle is provided. In this electric vehicle, the generator controller obtains the PI modulation torque Tor_PI corresponding to the target speed difference through the PI controller, and obtains the water temperature compensation torque Tor_tmot corresponding to the real-time engine water temperature from a pre-calibrated torque compensation relationship, and / or obtains the feedforward torque Tor_Ang corresponding to the engine crankshaft angle difference from a pre-calibrated feedforward torque relationship. Finally, the generator controller determines the generator target torque Tor_motor based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang to control the generator.
[0050] In other words, this embodiment adds torque compensation control based on engine coolant temperature, which can compensate for differences in engine torque at different coolant temperatures in advance, and / or adds torque feedforward control based on engine crankshaft angle differences, which can compensate for differences in engine torque at different engine crankshaft positions in advance. Therefore, it can reduce the PI adjustment amount in generator speed control, thereby reducing speed fluctuations and achieving precise control of generator speed, thus improving the NVH performance of electric vehicles. It is also worth noting that through the precise adjustment of this embodiment, the engine can adopt multiple ignition angle reduction or lean-burn schemes without causing speed instability, thus reducing pollutant emissions during the ignition phase and ultimately achieving the goal of reducing catalytic converter costs.
[0051] In one embodiment of the electric vehicle provided in conjunction with the above embodiments, the generator controller determines the generator target torque based on the PI-modulated torque, the water temperature compensation torque, and / or the feedforward torque, including: The generator controller adds the PI modulation torque to the water temperature compensation torque to obtain the generator target torque; or; The generator controller adds the PI-modulated torque to the feedforward torque to obtain the generator target torque; or; The generator controller adds the PI modulation torque, the water temperature compensation torque, and the feedforward torque to obtain the generator target torque.
[0052] In this embodiment, corresponding to the aforementioned electric vehicle embodiment, three specific methods for obtaining the generator target torque Tor_motor are provided for the electric vehicle. These methods are directly added together for compensation, thereby achieving precise control of the generator speed, reducing generator speed fluctuations, improving the NVH performance of the electric vehicle, and ensuring the feasibility of the solution. It is worth noting that in other embodiments, in the process of determining the generator target torque Tor_motor based on the PI modulation torque Tor_PI, the water temperature compensation torque Tor_tmot, and / or the feedforward torque Tor_Ang, in addition to directly adding the PI modulation torque Tor_PI, the water temperature compensation torque, and / or the feedforward torque Tor_Ang for compensation, other adjustments and supplements can also be made, such as adding other compensation torques such as injection timing torque compensation. The specific method is not limited.
[0053] In one embodiment of the electric vehicle provided in conjunction with the above embodiments, the engine entering the preset operating condition includes the engine entering the catalytic converter heating stage.
[0054] In this embodiment, an electric vehicle provided by this application, after the electric vehicle operates in the catalytic converter heating stage, adds torque compensation control based on engine coolant temperature, which can compensate for the difference in engine torque under different coolant temperatures in advance, and / or adds torque feedforward control based on engine crankshaft angle difference, which can compensate for the difference in engine torque under different engine crankshaft positions in advance. Therefore, after the electric vehicle enters the catalytic converter heating condition, the PI adjustment amount in the generator speed control can be reduced, thereby reducing speed fluctuations. After entering the catalytic converter heating condition, the generator speed can be accurately controlled, reducing the generator speed fluctuations caused by catalytic converter heating, thereby improving the NVH performance of the electric vehicle.
[0055] In one embodiment of the electric vehicle provided in conjunction with the above embodiments, the feedforward torque relationship characterizes the correspondence between different calibrated engine crankshaft angle differences and calibrated feedforward torque, wherein each calibrated engine crankshaft angle difference is a crankshaft angle difference between preset time intervals, and the preset time interval is ≤1ms.
[0056] In one embodiment of the electric vehicle provided in conjunction with the above embodiments, the electric vehicle further includes an engine controller and a vehicle controller; Before obtaining the water temperature compensation torque corresponding to the real-time engine water temperature and / or the feedforward torque corresponding to the engine crankshaft angle difference, the engine controller determines the engine target torque based on the engine target speed and the target power issued by the vehicle controller. The engine controller controls the engine to operate at the engine target torque.
[0057] In one embodiment of the electric vehicle provided in conjunction with the above embodiments, the engine controller controls the engine to operate at the engine target torque, including: The engine controller controls the engine to operate at the engine target torque in torque closed-loop mode.
[0058] In the electric vehicle provided in this embodiment, the engine operation control processing is limited to certain preset operating conditions, such as the engine operation control processing after entering the catalyst heating stage. Specifically, after entering the catalyst heating stage, the vehicle controller can issue a target power P and a target speed Speed_goal according to the heating requirements or heating conditions and other requirements, so that the engine can work in torque closed-loop mode or other modes according to the engine target torque Tor_engine, confirming the catalyst heating condition, thereby meeting the optimal emission requirements.
[0059] It should be noted that for details regarding this electric vehicle embodiment, please refer to the corresponding descriptions of the aforementioned method embodiments; these descriptions will not be repeated here.
[0060] In one embodiment, a generator speed control device is provided, which corresponds one-to-one with the generator speed control method described in the above embodiments. For example... Figure 4 As shown, the generator speed control device includes a first acquisition module 101, a second acquisition module 102, a determination module 103, and a control module 104. Detailed descriptions of each functional module are as follows: The first acquisition module 101 is used to acquire the PI modulation torque corresponding to the target speed difference through the PI controller after the engine enters the preset operating condition. The target speed difference is the difference between the engine target speed and the engine real-time speed. The second acquisition module 102 is used to obtain the water temperature compensation torque corresponding to the real-time water temperature of the engine from a pre-calibrated torque compensation relationship, and / or obtain the feedforward torque corresponding to the crankshaft angle difference of the engine from a pre-calibrated feedforward torque relationship. The determining module 103 is used to determine the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque; The control module 104 is used to control the generator to operate in torque closed-loop mode at the generator target torque.
[0061] In one embodiment, the determining module 103 is used to: The PI modulation torque is added to the water temperature compensation torque to obtain the generator target torque; or; The PI modulation torque is added to the feedforward torque to obtain the generator target torque; or; The PI modulation torque, the water temperature compensation torque, and the feedforward torque are added together to obtain the generator target torque.
[0062] In one embodiment, the engine entering the preset operating condition includes the engine entering the catalytic converter heating stage.
[0063] In one embodiment, the feedforward torque relationship characterizes the correspondence between different calibrated engine crankshaft angle differences and calibrated feedforward torques, wherein each calibrated engine crankshaft angle difference is a crankshaft angle difference between preset time intervals, and the preset time interval is ≤1ms.
[0064] This embodiment provides a generator speed control device applicable to a generator controller. This device incorporates torque compensation control based on engine coolant temperature, which can compensate for differences in engine torque at different coolant temperatures, and / or torque feedforward control based on engine crankshaft angle differences, which can compensate for differences in engine torque at different crankshaft positions. Therefore, it reduces the PI adjustment amount in generator speed control, thereby reducing speed fluctuations and achieving precise control of the generator speed, thus improving the NVH performance of electric vehicles. It is also worth noting that the precise adjustment in this embodiment allows the engine to employ multiple ignition angle reductions or lean-burn schemes without causing speed instability, thus reducing pollutant emissions during the ignition phase and ultimately achieving the goal of reducing catalytic converter costs.
[0065] For specific limitations regarding the generator speed control device, please refer to the limitations on the automotive actuator control method mentioned above, which will not be repeated here. Each module in the aforementioned automotive actuator control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.
[0066] In one embodiment, a motor controller is provided, the internal structure of which can be shown in the following diagram. Figure 5 As shown, the motor controller includes a processor, memory, and network interface connected via a system bus. The processor provides computational and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The processor's network interface is used for communication with other controllers in the electric vehicle via a network connection. When the computer program is executed by the processor, it implements the functions or steps of the motor controller in a generator speed control method.
[0067] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, it implements a generator speed control method mentioned in any of the above embodiments, which will not be repeated here.
[0068] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.
[0069] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.
[0070] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.
Claims
1. A generator speed control method, characterized in that, The method includes: After the engine enters the preset operating condition, the PI controller obtains the PI modulation torque corresponding to the target speed difference, where the target speed difference is the difference between the engine target speed and the engine real-time speed. The water temperature compensation torque corresponding to the engine real-time water temperature is obtained from the pre-calibrated torque compensation relationship, and / or the feedforward torque corresponding to the engine crankshaft angle difference is obtained from the pre-calibrated feedforward torque relationship. The generator target torque is determined based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque. The generator is controlled to operate in closed-loop mode at the target torque of the generator.
2. The generator speed control method as described in claim 1, characterized in that, Determining the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque includes: The PI modulation torque is added to the water temperature compensation torque to obtain the generator target torque; or; The PI modulation torque is added to the feedforward torque to obtain the generator target torque; or; The PI modulation torque, the water temperature compensation torque, and the feedforward torque are added together to obtain the generator target torque.
3. The generator speed control method as described in claim 1, characterized in that, The engine entering the preset operating condition includes the engine entering the catalytic converter heating stage.
4. The generator speed control method as described in claim 1, characterized in that, The feedforward torque relationship characterizes the correspondence between the crankshaft angle difference of different calibrated engines and the calibrated feedforward torque. Each calibrated engine crankshaft angle difference is the crankshaft angle difference between preset time intervals, and the preset time interval is ≤1ms.
5. The generator speed control method according to any one of claims 1-3, characterized in that, Before obtaining the water temperature compensation torque corresponding to the real-time engine water temperature, and / or the feedforward torque corresponding to the engine crankshaft angle difference, the method further includes: The target engine torque is determined based on the target engine speed and the target power output from the vehicle controller. Control the engine to operate at the target engine torque.
6. The generator speed control method as described in claim 5, characterized in that, The control of the engine to operate at the engine target torque includes: The engine is controlled to operate in torque closed-loop mode at the engine target torque.
7. A generator speed control device, characterized in that, include: The first acquisition module is used to acquire the PI modulation torque corresponding to the target speed difference through the PI controller after the engine enters the preset operating condition. The target speed difference is the difference between the engine target speed and the engine real-time speed. The second acquisition module is used to obtain the water temperature compensation torque corresponding to the real-time water temperature of the engine from a pre-calibrated torque compensation relationship, and / or obtain the feedforward torque corresponding to the crankshaft angle difference of the engine from a pre-calibrated feedforward torque relationship. The determination module is used to determine the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque; A control module is used to control the generator to operate in torque closed-loop mode at the generator's target torque.
8. A car, characterized in that, The vehicle includes an engine, a generator, and a generator controller: After the engine enters the preset operating condition, the generator controller obtains the PI modulation torque corresponding to the target speed difference through the PI controller. The target speed difference is the difference between the engine target speed and the engine real-time speed. The generator controller obtains the water temperature compensation torque corresponding to the real-time engine water temperature from a pre-calibrated torque compensation relationship, and / or obtains the feedforward torque corresponding to the engine crankshaft angle difference from a pre-calibrated feedforward torque relationship. The generator controller determines the generator target torque based on the PI modulation torque, the water temperature compensation torque, and / or the feedforward torque; The generator controller controls the generator to operate in torque closed-loop mode at the generator target torque.
9. The automobile as described in claim 8, characterized in that, The generator controller determines the target torque of the generator based on the PI-modulated torque, the water temperature compensation torque, and / or the feedforward torque, including: The generator controller adds the PI modulation torque to the water temperature compensation torque to obtain the generator target torque; or; The generator controller adds the PI-modulated torque to the feedforward torque to obtain the generator target torque; or; The generator controller adds the PI modulation torque, the water temperature compensation torque, and the feedforward torque to obtain the generator target torque.
10. The automobile as described in claim 8, characterized in that, The engine entering the preset operating condition includes the engine entering the catalytic converter heating stage.
11. The automobile as described in claim 8, characterized in that, The feedforward torque relationship characterizes the correspondence between the crankshaft angle difference of different calibrated engines and the calibrated feedforward torque. Each calibrated engine crankshaft angle difference is the crankshaft angle difference between preset time intervals, and the preset time interval is ≤1ms.
12. The automobile as described in any one of claims 8-11, characterized in that, The electric vehicle also includes an engine controller and a vehicle controller; Before obtaining the water temperature compensation torque corresponding to the real-time engine water temperature and / or the feedforward torque corresponding to the engine crankshaft angle difference, the engine controller determines the engine target torque based on the engine target speed and the target power issued by the vehicle controller. The engine controller controls the engine to operate at the engine target torque.
13. The electric vehicle as described in claim 12, characterized in that, The engine controller controls the engine to operate at the engine target torque, including: The engine controller controls the engine to operate at the engine target torque in torque closed-loop mode.
14. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the generator speed control method as described in any one of claims 1 to 6.