Control method for dual-motor hybrid system of hybrid vehicle, and apparatus

Abstract

A control method for a dual-motor hybrid system of a hybrid vehicle, comprising: when a dual-motor hybrid system is in a parallel mode, acquiring input shaft request torque requesting an output of an input shaft of a transmission (5) and first motor request torque requesting an output of a first motor (2); and, in response to the input shaft request torque being greater than the torque capacity of a clutch (4) and the difference between the input shaft request torque and the torque capacity of the clutch (4) being less than the speed regulation intervention torque capacity of the input shaft, controlling the first motor (2) to output the sum of the first motor request torque and intervention negative torque, and controlling an engine (1) to output engine torque, the absolute value of the intervention negative torque being less than or equal to the difference between the input shaft request torque and the torque capacity of the clutch (4), the engine torque being positive torque which is equal to the difference between the torque capacity of the clutch (4) and the intervention negative torque, and the torque capacity of the clutch (4) being the maximum torque which can be transmitted by the clutch. The method can quickly increase the rotating speed of input shafts of transmissions. Further disclosed is a dual-motor hybrid system apparatus for a hybrid vehicle.

Description

Control method and device for dual-motor hybrid system of hybrid electric vehicle Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a control method and device for a dual-motor hybrid system of a hybrid electric vehicle. Background Art

[0002] Currently, some hybrid vehicles are equipped with dual-motor hybrid systems. Controlling the output torque of the dual-motor hybrid system affects the power and drivability of the entire vehicle.

[0003] The dual-motor hybrid system's clutch connects the two motors. The dual-motor hybrid system operates in both series and parallel modes. When the hybrid vehicle operates in parallel mode, if the transmission's input shaft torque request exceeds the clutch's torque capacity, torque intervention control of the dual-motor hybrid system is required without exceeding the clutch's torque capacity.

[0004] Summary of the Invention

[0005] The present application provides a control method and device for a dual-motor hybrid system of a hybrid electric vehicle.

[0006] The present application provides a control method for a dual-motor hybrid system of a hybrid vehicle, wherein the dual-motor hybrid system includes an engine, a first motor, a second motor, a transmission, and a clutch, wherein the first motor is drivingly connected to the engine, the input shaft of the transmission is connected to the engine, the first motor, and the second motor, and the clutch is connected to the second motor and the first motor respectively;

[0007] The method comprises:

[0008] When the dual-motor hybrid system is in a parallel mode, obtaining an input shaft request torque and a first motor request torque;

[0009] In response to the input shaft requested torque being greater than the torque capacity of the clutch, and the difference between the input shaft requested torque and the torque capacity of the clutch being less than the speed regulation intervention torque capacity of the input shaft, the first motor is controlled to output the sum of the first motor requested torque and the intervention negative torque, and the engine is controlled to output the engine torque; wherein the absolute value of the intervention negative torque is less than or equal to the difference between the input shaft requested torque and the torque capacity of the clutch; the engine torque is a positive torque, which is equal to the difference between the torque capacity of the clutch and the intervention negative torque; and the torque capacity of the clutch is the maximum torque that the clutch can transmit.

[0010] Optionally, controlling the first motor to output the sum of the first motor requested torque and the intervention negative torque, and controlling the engine to output the engine torque, includes:

[0011] The first motor is controlled to output a sum of the first motor request torque and a maximum intervention negative torque that can be output by the first motor; and the engine torque is equal to a difference between the torque capacity of the clutch and the maximum intervention negative torque.

[0012] Optionally, after controlling the engine to output engine torque, the method includes:

[0013] In response to a sum of the engine torque output by the engine and the maximum intervention negative torque being less than the input shaft request torque, the second motor is controlled to output a second motor torque, wherein the sum of the second motor torque, the engine torque, and the maximum intervention negative torque that can be output by the first motor is equal to the input shaft request torque.

[0014] Optionally, the method further includes:

[0015] When the hybrid vehicle is in a power upshift mode, in response to a gear shift speed regulation request in the mode, obtaining a requested torque of the second motor, and determining a speed regulation intervention torque of the input shaft according to the gear shift speed regulation request;

[0016] In response to the speed intervention torque being less than or equal to the speed intervention torque capacity of the second electric machine, the second electric machine is controlled to output a sum of the speed intervention torque and a second electric machine requested torque.

[0017] Optionally, the method includes:

[0018] In response to the speed intervention torque being greater than the speed intervention torque capacity of the second motor and less than or equal to the speed intervention torque capacity of the input shaft, the second motor is controlled to output the sum of the speed intervention torque capacity of the second motor and the second motor requested torque, and the first motor and / or the engine is controlled to output the remaining intervention torque, wherein the remaining intervention torque is the difference between the speed intervention torque and the speed intervention torque capacity of the second motor.

[0019] Optionally, the hybrid vehicle includes a battery, the first motor is electrically connected to the battery, and controlling the first motor or the engine to output the remaining intervention torque includes:

[0020] obtaining the negative power capacity of the battery;

[0021] In response to the negative power capacity being less than or equal to a negative power capacity threshold, the first motor is controlled to output a first motor intervention torque; the first motor intervention torque is less than or equal to the residual intervention torque, and the first motor intervention torque is positive torque or negative torque.

[0022] Optionally, controlling the first motor and / or the engine to output a remaining intervention torque includes:

[0023] In response to the negative power capacity being less than or equal to a negative power capacity threshold and the remaining intervention torque being less than or equal to a speed regulation intervention torque capability of the first motor, controlling the first motor to output the first motor intervention torque, the first motor intervention torque being equal to the remaining intervention torque;

[0024] Optionally, the control of the first motor and / or the engine outputting the remaining intervention torque response includes: in response to the negative power capacity being less than or equal to a negative power capacity threshold, and the remaining intervention torque being greater than the speed intervention torque capacity of the first motor, controlling the first motor to output the speed intervention torque capacity of the first motor, and controlling the engine to output the engine intervention torque, the engine intervention torque being equal to the difference between the remaining intervention torque and the speed intervention torque capacity of the first motor.

[0025] Optionally, after obtaining the negative power capacity of the battery, the method further includes:

[0026] In response to the negative power capacity being greater than the negative power capacity threshold, the torque output by the first electric machine is reduced within a positive torque interval.

[0027] Optionally, after obtaining the negative power capacity of the battery, the method further includes:

[0028] In response to the negative power capacity being greater than the negative power capacity threshold and the positive torque output by the first electric machine being less than the remaining intervention torque, the engine is controlled to output an engine intervention torque, the engine intervention torque being equal to a difference between the remaining intervention torque and the positive torque output by the first electric machine.

[0029] Optionally, the clutch comprises a shift clutch, which is engaged when the hybrid vehicle is in the power upshift mode; the method further comprises:

[0030] In response to the speed intervention torque being greater than the speed intervention torque capacity of the input shaft, the second motor is controlled to output the sum of the speed intervention torque capacity of the second motor and the second motor requested torque, the engine is controlled to output the speed intervention torque capacity of the engine, and according to the negative power capacity of the battery, the first motor is controlled, and the shifting clutch output torque is controlled according to the difference between the speed intervention torque and the speed intervention torque capacity of the input shaft.

[0031] Optionally, controlling the output torque of the shift clutch according to the difference between the speed regulation intervention torque and the speed regulation intervention torque capacity of the input shaft includes:

[0032] determining an adjustment torque according to a series-parallel mode, a shift mode, a gear position, a target speed change rate of the input shaft, and an actual speed change rate of the input shaft of the dual-motor hybrid system;

[0033] determining an output torque of the shift clutch according to a difference between the speed regulation intervention torque and the speed regulation intervention torque capacity of the input shaft, the feedforward torque of the clutch, and the adjustment torque;

[0034] The shifting clutch is controlled to output the output torque.

[0035] Optionally, the speed regulation intervention torque capacity of the input shaft is the sum of the speed regulation intervention torque capacity of the first motor, the speed regulation intervention torque capacity of the second motor and the speed regulation intervention torque capacity of the engine.

[0036]

[0037] The present application provides a computer-readable storage medium comprising one or more processors for executing the control method of a dual-motor hybrid system of a hybrid electric vehicle as described in any one of the above.

[0038] The present application provides a control device for a dual-motor hybrid system of a hybrid electric vehicle, comprising one or more processors for executing any of the control methods for the dual-motor hybrid system of a hybrid electric vehicle described above.

[0039] The present application also provides a hybrid electric vehicle, comprising:

[0040] A dual-motor hybrid system includes an engine, a first motor, a second motor, a transmission, and a clutch, wherein the first motor is drivingly connected to the engine, an input shaft of the transmission is connected to the engine, the first motor, and the second motor, and the clutch is connected to the second motor and the first motor respectively; and

[0041] The control device of the dual-motor hybrid system of the hybrid vehicle as described above is electrically connected to the dual-motor hybrid system.

[0042] In some embodiments, a dual-motor hybrid system includes an engine, a first motor, a second motor, a transmission and a clutch, and the clutch is connected to the first motor and the second motor respectively; when the dual-motor hybrid system is in parallel mode, in response to the input shaft request torque being greater than the torque capacity of the clutch, the first motor is controlled to output negative torque, and based on the negative torque, the engine is controlled to output positive torque. In this way, the speed of the input shaft of the transmission can be increased more quickly by controlling the first motor and the engine to output intervention torque without exceeding the torque capacity of the clutch, thereby maintaining the driving performance of the vehicle.

[0043] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0045] FIG1 is a schematic structural diagram of a hybrid vehicle in series mode provided by an embodiment of the present application.

[0046] FIG2 is a schematic structural diagram of a hybrid vehicle in parallel mode provided by an embodiment of the present application.

[0047] FIG3 is a schematic diagram showing a hybrid architecture to which a control method for a dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present application is applied.

[0048] FIG4 is a flow chart showing a method for controlling a dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present application.

[0049] FIG5 is a flow chart showing a method for controlling a dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present application.

[0050] FIG6 is a flowchart showing the step of “controlling the first motor or the engine to output the remaining intervention torque, or controlling the first motor and the engine to jointly output the remaining intervention torque” shown in FIG5 provided in an embodiment of the present application.

[0051] FIG7 is a block diagram showing a structure of a control device for a dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present application. DETAILED DESCRIPTION

[0052] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0053] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. Unless otherwise defined, technical or scientific terms used in this application should have the ordinary meaning understood by a person of ordinary skill in the art to which this application belongs. The terms "first," "second," and similar words used in this specification and claims do not denote any order, quantity, or importance, but are simply used to distinguish different components. Similarly, the terms "a" or "an" and similar words do not denote a limitation of quantity, but rather denote the presence of at least one. The terms "plurality" or "several" mean two or more. Unless otherwise indicated, the terms "front," "rear," "lower," and / or "upper" and similar words are for convenience only and are not intended to limit to a single position or spatial orientation. The terms "include" or "comprising" and similar words mean that the elements or objects listed before "include" or "comprising" include the elements or objects listed after "include" or "comprising" and their equivalents, and do not exclude other elements or objects. The terms "connected" or "connected" and similar words are not limited to physical or mechanical connections and can include electrical connections, whether direct or indirect.

[0054] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. As used in this application and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0055] A dual-motor hybrid system according to an embodiment of the present application includes an engine, a first motor, a second motor, a transmission, and a clutch. The first motor is connected to the engine, the transmission input shaft is connected to the engine, the first motor, and the second motor, respectively. The clutch is connected to the second motor and the first motor, respectively. A method includes: when the dual-motor hybrid system is in parallel mode, obtaining an input shaft request torque requested from the transmission input shaft and a first motor request torque requested from the first motor; in response to the input shaft request torque being greater than the clutch torque capacity, and the difference between the input shaft request torque and the clutch torque capacity being less than the input shaft speed regulation intervention torque capacity, controlling the first motor to output the sum of the first motor request torque and the intervention negative torque; controlling the engine to output engine torque, wherein the absolute value of the intervention negative torque is less than or equal to the difference between the input shaft request torque and the clutch torque capacity, and the engine torque is positive torque equal to the difference between the clutch torque capacity and the intervention negative torque; the clutch torque capacity is the maximum torque that the clutch can transmit. This application allows for rapid changes in the transmission input shaft speed.

[0056] This application provides a control method and device for a dual-motor hybrid system for a hybrid electric vehicle. The control method and device for a dual-motor hybrid system for a hybrid electric vehicle of this application are described in detail below, in conjunction with the accompanying drawings. The features of the following embodiments and implementations may be combined with each other unless they conflict.

[0057] FIG1 is a schematic diagram of the structure of a hybrid vehicle in series mode provided by an embodiment of the present application. FIG2 is a schematic diagram of the structure of a hybrid vehicle in parallel mode provided by an embodiment of the present application. As shown in FIG1 and FIG2 , the dual-motor hybrid system of a hybrid vehicle has three modes: pure electric mode, series mode and parallel mode, and the hybrid vehicle can switch between these modes. As shown in FIG1 and FIG2 , the dual-motor hybrid system includes an engine 1 (represented by ICE in the figure), a first motor 2 (represented by P1 in the figure), a second motor 3 (represented by P2 in the figure, the second motor 3 can also be called a drive motor), a transmission 5 and a clutch 4 (represented by C0 in the figure). The first motor 2 is connected to the engine 1 in a driving manner and can drive the engine 1 to start. The input shaft of the transmission 5 is connected to the engine 1, the first motor 2 and the second motor 3, and the clutch 4 is connected to the second motor 3 and the first motor 2 respectively.

[0058] The hybrid vehicle includes a battery 6, and a first motor 2 electrically connected to the battery 6. The first motor 2 can be used to generate electricity to charge the battery 6. As shown in Figure 1, in series mode, the clutch 4 is disengaged, and the engine 1 supplies power to the battery 6 and the second motor 3 via the first motor 2. The second motor 3 drives the wheels via the transmission 5. As shown in Figure 2, in parallel mode, the clutch 4 is engaged (also called coupled), and the engine 1 and the second motor 3 jointly drive the wheels via the transmission 5.

[0059] The control method for the dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present application can be applied to the hybrid architecture shown in FIG3 . As shown in FIG3 , the hybrid architecture includes a first power mechanism, a second power mechanism, and a transmission architecture. The first power mechanism includes an engine ICE and a first motor P1 connected to each other, and the second power mechanism includes a second motor P2. The transmission mechanism includes a fourth clutch C0 that can be used for mode switching, a double-row planetary gear, a first clutch B1 that can be used for gear shifting control, a second clutch B2, and a third clutch C3. The double-row planetary gear includes a first planetary gear consisting of a first sun gear S1, a first planet carrier PC1, and a first ring gear R1, and a second planetary gear consisting of a second sun gear S2, a second planet carrier PC2, and a second ring gear R2.

[0060] As shown in Figure 3, the output shaft of the first motor P1 can be connected to the second sun gear S2 via the fourth clutch C0 to drive the second sun gear S2. The output shaft of the second motor P2 is also connected to the second sun gear S2 to drive the second sun gear S2. The output shaft of the second motor P2 can also be connected to the first sun gear S1 via the third clutch C3 to drive the first sun gear S1. The first sun gear S1 is connected to one end of the second clutch B2, the other end of which is connected to the hydraulic system. The first planet carrier PC1 is connected to the second ring gear R2. The first planet carrier PC1 and the second ring gear R2 are both connected to one end of the first clutch B1, the other end of which is connected to the hydraulic system. The first ring gear R1 is connected to the second planet carrier PC2. The power input to the double-row planetary gears is transmitted to the wheel ends via the output shaft connected to the first ring gear R1 and the second planet carrier PC2.

[0061] The hybrid architecture described above enables shifting between forward gears. Of the first, second, and third clutches (B1, B2, and C3), first gear is achieved when only first clutch B1 is engaged, second gear is achieved when only second clutch B2 is engaged, and third gear is achieved when only third clutch C3 is engaged. Gear shifting is achieved by disengaging one of the clutches (the offgoing clutch) and engaging the other (the oncoming clutch). The offgoing clutch is also referred to as the active clutch, and the oncoming clutch is also referred to as the passive clutch. When the states of the offgoing and oncoming clutches change, the shift in power transmission path causes a change in the transmission ratio, thus enabling gear shifting.

[0062] Although a hybrid architecture applicable to the embodiment of the present application is shown above, the control method of the dual-motor hybrid system of the hybrid vehicle in the embodiment of the present application is not limited to a specific hybrid architecture.

[0063] The shifting process of the embodiment of the present application includes three stages: the oil filling stage, the torque exchange stage, and the gear shift speed regulation stage. When the gear shift type is power upshift (Power-on upshift) and non-power downshift (Power-off downshift), the order of the three stages is: the oil filling stage, the torque exchange stage and the gear shift speed regulation stage. When the gear shift type is power downshift (Power-on downshift) and non-power upshift (Power-off upshift), the order of the three stages is: the oil filling stage, the gear shift speed regulation stage and the torque exchange stage. Among them, power upshift can also be called accelerator upshift, power downshift can also be called accelerator downshift, non-power upshift can also be called accelerator upshift, and non-power downshift can also be called accelerator downshift.

[0064] The clutch 4 includes a shift clutch. The shift clutch is engaged when the hybrid vehicle is in a power upshift mode. In the embodiment shown in FIG3 , the shift clutch can be a second clutch B2 or a third clutch C3.

[0065] Before the on-coming clutch engages, a certain gap exists between the clutch's active portion (e.g., the driving plate) and the driven portion (e.g., the driven plate). During the filling phase, the clutch is controlled to quickly eliminate this gap, enabling the clutch to reach torque transmission in a shorter period of time. The speed of clutch filling and the pressure response after filling significantly impact drivability and dynamic response during the shift process.

[0066] During the torque exchange phase, the off-going clutch is disengaged and the on-coming clutch is engaged simultaneously, and the clutch torque is exchanged from the off-going clutch to the on-coming clutch.

[0067] During the shift and speed control phase, the transmission control unit generates inertial torque (also known as speed intervention torque) by sending a torque reduction or increase request. This inertial torque changes the speed of the powertrain (e.g., engine 1) until the target speed is reached.

[0068] During the torque exchange phase, torque control of the off-going and on-coming clutches is performed at set time intervals. This can be achieved based on a progress percentage, which is equal to the ratio of the current exchange time to the torque exchange duration (i.e., the duration of the torque exchange phase). The current exchange time is equal to the current time minus the start time of the torque exchange phase. Typically, during the torque exchange process, the shift torque allocated to the off-going and on-coming clutches varies linearly (i.e., the absolute value of the shift torque gradient remains unchanged), with the shift torque allocated to the off-going clutch decreasing linearly over time, while the shift torque allocated to the on-coming clutch increases linearly over time.

[0069] FIG4 is a flow chart of a method for controlling a dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present invention. As shown in FIG4 , a method 20 for controlling a dual-motor hybrid system of a hybrid vehicle includes steps 21 to 24 .

[0070] Step 21 : When the dual-motor hybrid system is in the parallel mode, obtain the input shaft request torque of the transmission 5 and the first motor request torque of the first motor 2 .

[0071] In step 22 , it is determined whether the input shaft request torque is greater than the torque capacity of the clutch 4 .

[0072] In response to the input shaft request torque being less than or equal to the torque capacity of the clutch 4 , step 23 is executed without performing torque intervention.

[0073] In response to the input shaft requested torque being greater than the torque capacity of clutch 4, step 24 is executed. In response to the difference between the input shaft requested torque and the torque capacity of clutch 4 being less than the speed regulation intervention torque capacity of the input shaft, first motor 2 is controlled to output the sum of the first motor requested torque and the intervention negative torque, and engine 1 is controlled to output engine torque. The absolute value of the intervention negative torque is less than or equal to the difference between the input shaft requested torque and the torque capacity of clutch 4, and the engine torque is a positive torque equal to the difference between the torque capacity of clutch 4 and the intervention negative torque. The torque capacity of clutch 4 is the maximum torque that clutch 4 can transmit. In the embodiment shown in FIG3 , clutch 4 includes a fourth clutch C0, and the torque capacity of clutch 4 is the maximum torque that fourth clutch C0 can transmit.

[0074] The speed regulation intervention torque capacity of the input shaft is determined by the speed regulation intervention torque capacities of the first motor 2 , the second motor 3 , and the engine 1 .

[0075] The speed regulation intervention torque capability of the first motor 2 can be determined by the following method:

[0076] Maximum speed regulation intervention torque = max (unintervention first motor request torque, first motor maximum torque capacity) - unintervention first motor request torque;

[0077] Minimum speed regulation intervention torque=min(requested torque of the first electric machine without intervention, minimum torque capacity of the first electric machine)−requested torque of the first electric machine without intervention.

[0078] The speed intervention torque capability of the first motor 2 includes a maximum speed intervention torque and a minimum speed intervention torque of the first motor 2. The maximum speed intervention torque of the first motor 2 is determined based on the difference between the unintervention first motor request torque and the first motor maximum torque capability, whichever is greater, and the unintervention first motor request torque. The minimum speed intervention torque of the first motor 2 is determined based on the difference between the unintervention first motor request torque and the first motor minimum torque capability, whichever is less, and the unintervention first motor request torque.

[0079] The speed regulation intervention torque capability of the second motor 3 can be determined by the following method:

[0080] Maximum speed regulation intervention torque = max (unintervention second motor request torque, second motor maximum torque capacity) - unintervention second motor request torque;

[0081] Minimum speed regulation intervention torque=min(the requested torque of the second electric machine without intervention, the minimum torque capacity of the second electric machine)−the requested torque of the second electric machine without intervention.

[0082] The speed intervention torque capability of the second motor 3 includes a maximum speed intervention torque and a minimum speed intervention torque of the second motor 3. The maximum speed intervention torque of the second motor 3 is determined based on the difference between the unintervention second motor request torque and the second motor maximum torque capability, whichever is greater. The minimum speed intervention torque of the second motor 3 is determined based on the difference between the unintervention second motor request torque and the second motor minimum torque capability, whichever is less.

[0083] The speed intervention torque capability of engine 1 includes a maximum speed intervention torque and a minimum speed intervention torque of engine 1. The maximum speed intervention torque of engine 1 is determined based on the difference between the unintervention engine request torque and the maximum engine torque capability, whichever is greater, and the unintervention engine request torque. The minimum speed intervention torque of engine 1 is determined based on the difference between the unintervention engine request torque and the minimum engine torque capability, whichever is less, and the unintervention engine request torque.

[0084] The speed regulation intervention torque capacity of the input shaft=the speed regulation intervention torque capacity of the first motor 2 + the speed regulation intervention torque capacity of the second motor 3 + the speed regulation intervention torque capacity of the engine 1 .

[0085] If the input shaft requested torque exceeds the torque capacity of clutch 4, it indicates that the input shaft of clutch 4 is unable to output the requested input shaft torque. In response to the difference between the input shaft requested torque and the torque capacity of clutch 4 being less than the input shaft's speed regulation intervention torque capacity, first motor 2 is controlled to output the sum of the first motor requested torque and the intervention negative torque, while engine 1 is controlled to output a positive engine torque. For example, the intervention negative torque of first motor 2 can be first determined, and based on the intervention negative torque, engine 1 is controlled to output a positive torque; then first motor 2 is controlled to output the sum of the first motor requested torque and the intervention negative torque. This maximizes the positive torque output of engine 1 without exceeding the torque capacity of clutch 4, which helps increase the engine speed. For example, if the first motor requested torque is 0 Nm, the input shaft requested torque is 400 Nm, the clutch 4 torque capacity is 300 Nm, and the speed regulation intervention torque capacity of first motor 2 is ±100 Nm, first motor 2 is controlled to output a negative torque of -100 Nm, and engine 1 is controlled to output 400 Nm.

[0086] In some embodiments, in step 24, controlling the first motor 2 to output the sum of the first motor request torque and the intervention negative torque, and controlling the engine 1 to output the engine torque, includes:

[0087] First motor 2 is controlled to output the sum of the first motor request torque and the maximum intervention negative torque that the first motor can output; the engine torque is equal to the difference between the torque capacity of clutch 4 and the maximum intervention negative torque. The maximum intervention negative torque is the intervention negative torque with the largest absolute value.

[0088] In response to the sum of the engine torque output by engine 1 and the maximum negative intervention torque being less than the input shaft requested torque, second motor 3 is controlled to output a second motor torque. The sum of the second motor torque, the engine torque, and the maximum negative intervention torque output by the first motor equals the input shaft requested torque. For example, if the input shaft requested torque is 500 Nm, the torque capacity of clutch 4 is 300 Nm, and the speed regulation intervention torque capacity of first motor 2 is ±100 Nm, first motor 2 is controlled to output a negative torque of -100 Nm, engine 1 is controlled to output a torque of 400 Nm, and second motor 3 is controlled to output a torque of 200 Nm.

[0089] Controlling first motor 2 to output maximum negative intervention torque enables engine 1 to output maximum positive torque, which helps increase engine speed. In response to the sum of the intervention torques output by engine 1 and first motor 2 being less than the requested input shaft torque, second motor 3 is controlled to jointly output the intervention torque.

[0090] Figure 5 is a flow chart of a control method 20 for a dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present invention. As shown in Figure 5 , the control method for a dual-motor hybrid system of a hybrid vehicle includes steps 25 to 30.

[0091] Step 25 : When the hybrid vehicle is in the power upshift mode, in response to the gear shift speed regulation request in this mode, the second motor request torque is obtained, and the speed regulation intervention torque of the input shaft of the transmission 5 is determined according to the gear shift speed regulation request.

[0092] When a hybrid vehicle is in power upshift mode, during the torque exchange phase, it is typically necessary to control the first motor 2 to compensate for torque to reduce the deceleration caused by the upshift. This can lead to a slow speed drop during the shift and speed regulation phase. Furthermore, the increased feedforward torque of the clutch can lead to clutch overheating. Therefore, torque intervention is required during the shift and speed regulation phase. The input shaft speed regulation intervention torque is determined based on the shift and speed regulation request in this mode.

[0093] Step 26 , determining whether the speed regulation intervention torque is less than or equal to the speed regulation intervention torque capability of the second motor 3 .

[0094] In response to the speed intervention torque being less than or equal to the speed intervention torque capacity of the second motor 3 , step 27 is executed, in which the second motor 3 is controlled to output the sum of the speed intervention torque and the second motor request torque.

[0095] In response to the speed intervention torque being less than or equal to the speed intervention torque capacity of the second motor 3, it indicates that the second motor 3 can output the speed intervention torque. At this time, the torque output by the second motor 3 is the sum of the speed intervention torque and the second motor request torque.

[0096] Due to the fast response of the second motor 3, controlling the output torque of the second motor 3 allows for rapid adjustment of the transmission input shaft speed. The output torque of the second motor 3 is determined based on the requested second motor torque and the speed regulation intervention torque. This allows for rapid adjustment of the transmission input shaft speed by controlling the output intervention torque of the second motor 3, maintaining vehicle drivability.

[0097] Step 28 : In response to the speed regulation intervention torque being greater than the speed regulation intervention torque capability of the second motor, determining whether the speed regulation intervention torque is less than or equal to the speed regulation intervention torque capability of the input shaft.

[0098] In response to the speed intervention torque being greater than the speed intervention torque capacity of the second motor 3, it indicates that the torque output by the second motor 3 is insufficient to cover the speed intervention torque. At this time, it is necessary to determine whether the speed intervention torque is less than or equal to the speed intervention torque capacity of the input shaft.

[0099] In response to the absolute value of the speed intervention torque being less than or equal to the absolute value of the speed intervention torque capacity of the input shaft, step 29 is executed. In step 29, the second motor 3 is controlled to output the sum of the speed intervention torque capacity of the second motor 3 and the requested torque of the second motor, and the first motor 2 or the engine 1 is controlled to output the remaining intervention torque, or the first motor 2 and the engine 1 are controlled to jointly output the remaining intervention torque. The remaining intervention torque is the difference between the speed intervention torque and the speed intervention torque capacity of the second motor 3. The remaining intervention torque can be output by the first motor 2 or the engine 1 alone, or by both.

[0100] FIG6 is a flow chart illustrating the step "controlling the first motor 2 or the engine 1 to output the remaining intervention torque, or controlling the first motor 2 and the engine 1 to jointly output the remaining intervention torque" shown in FIG5 according to an embodiment of the present application. As shown in FIG6 , step 29 includes steps 291 to 294.

[0101] Step 291 , obtaining the negative power capacity of the battery 6 .

[0102] The negative power capacity of the battery 6 represents the capacity of the battery 6 that can be charged. When the first motor 2 is controlled to output torque, the battery 6 is charged. In order to prevent the battery 6 from being overcharged, the negative power capacity of the battery 6 needs to be obtained.

[0103] Step 292: Determine whether the negative power capacity is greater than a negative power capacity threshold.

[0104] In response to the negative power capacity being less than or equal to the negative power capacity threshold, step 293 is executed to control the first motor 2 to output a first motor intervention torque. The first motor intervention torque is less than or equal to the residual intervention torque and is positive or negative.

[0105] If the chargeable capacity of the battery 6 is sufficient, the first electric machine 2 outputs a first electric machine intervention torque.

[0106] In some embodiments, step 293 includes: in response to the remaining intervention torque being less than or equal to the speed regulation intervention torque capability of the first motor 2, controlling the first motor 2 to output the first motor intervention torque, and the first motor intervention torque being equal to the remaining intervention torque; in response to the remaining intervention torque being greater than the speed regulation intervention torque capability of the first motor 2, controlling the first motor 2 to output the speed regulation intervention torque capability of the first motor 2, and controlling the engine 1 to output the engine intervention torque, and the engine intervention torque being equal to the difference between the remaining intervention torque and the speed regulation intervention torque capability of the first motor 2.

[0107] If the speed regulation intervention torque capability of the first motor 2 is insufficient to cover the remaining intervention torque, it is necessary to control the engine 1 to output the engine intervention torque, and the engine 1 and the first motor 2 jointly output the remaining intervention torque.

[0108] In response to the negative power capacity being greater than the negative power capacity threshold, step 294 is executed. In step 294 , the torque output by the first motor 2 is reduced within the positive torque range.

[0109] If the charged capacity of the battery 6 is insufficient, in order to prevent the battery 6 from being overcharged, the torque output by the first motor 2 is reduced within the positive torque range. The torque output by the first motor 2 may be reduced from the positive torque to zero.

[0110] In some embodiments, step 294 includes: in response to the positive torque output by the first motor 2 being less than the residual intervention torque, controlling the engine 1 to output the engine intervention torque, where the engine intervention torque is equal to the difference between the residual intervention torque and the positive torque output by the first motor 2. If the positive torque output by the first motor 2 is insufficient to cover the residual intervention torque, then controlling the engine 1 to output the engine intervention torque is required, and the engine 1 and the first motor 2 jointly output the residual intervention torque.

[0111] Referring to Figure 5, in response to the speed intervention torque being greater than the speed intervention torque capacity of the transmission input shaft, step 30 is executed. In step 30, the second motor 3 is controlled to output the sum of the speed intervention torque capacity of the second motor 3 and the requested torque of the second motor, the engine 1 is controlled to output the speed intervention torque capacity of the engine, and according to the negative power capacity of the battery 6, the first motor 2 is controlled, and the shift clutch output torque is controlled according to the difference between the speed intervention torque and the speed intervention torque capacity of the input shaft.

[0112] If the speed intervention torque exceeds the input shaft's speed intervention torque capacity, it indicates that the input shaft's speed intervention torque capacity is insufficient to cover the speed intervention torque. To prevent battery 6 from overcharging, the torque output by first motor 2 is determined based on the negative power capacity of battery 6. The shift clutch output torque is controlled based on the difference between the speed intervention torque and the input shaft's speed intervention torque capacity.

[0113] In some embodiments, in step 30, controlling the output torque of the shift clutch according to the difference between the speed regulation intervention torque and the speed regulation intervention torque capacity of the input shaft includes the following steps:

[0114] Determining the adjustment torque based on the series / parallel mode, shift mode, gear position, target speed change rate of the input shaft, and actual speed change rate of the input shaft of the dual-motor hybrid system;

[0115] determining the output torque of the shift clutch according to the difference between the speed regulation intervention torque and the speed regulation intervention torque capacity of the input shaft, the feedforward torque of the clutch, and the regulating torque;

[0116] The shifting clutch is controlled to output the output torque.

[0117] The output torque of the shift clutch includes its adjustment torque, feedforward torque, and intervention torque. The adjustment torque is determined by multiplying the difference between the target speed change rate of the transmission input shaft and the actual speed change rate of the transmission input shaft by an adjustment coefficient. The feedforward torque is the sum of the engine torque, the motor torque, and the lockup torque. In some embodiments, the output torque of the shift clutch is controlled by the I term (integral term). The I term (integral term) adjustment coefficient is determined based on the series / parallel mode of the dual-motor hybrid system, the shift mode, the gear position, the target speed change rate of the input shaft, and the actual speed change rate of the input shaft.

[0118] Figure 7 shows a block diagram of a control device for a dual-motor hybrid system of a hybrid vehicle according to an embodiment of the present invention. The control device for a dual-motor hybrid system of a hybrid vehicle is electrically connected to the dual-motor hybrid system of the present invention for controlling the dual-motor hybrid system.

[0119] As shown in FIG7 , the control device of the dual-motor hybrid system of the hybrid electric vehicle includes one or more processors 41 for implementing the control method 20 of the dual-motor hybrid system of the hybrid electric vehicle as described above.

[0120] In some embodiments, the control device for a hybrid vehicle's dual-motor hybrid system may include a computer-readable storage medium 42 . The computer-readable storage medium 42 may store a program callable by a processor 41 and may include a non-volatile storage medium. In some embodiments, the control device for a hybrid vehicle's dual-motor hybrid system may include a memory 43 and an interface 44 . In some embodiments, the control device for a hybrid vehicle's dual-motor hybrid system may also include other hardware depending on the actual application.

[0121] The computer-readable storage medium 42 of the embodiment of the present application stores a program thereon, which, when executed by the processor 41 , is used to implement the control method 20 of the dual-motor hybrid system of the hybrid electric vehicle as described above.

[0122] The present application may take the form of a computer program product implemented on one or more computer-readable storage media 42 (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing program code. Computer-readable storage media 42 include permanent and non-permanent, removable and non-removable media, and may implement information storage by any method or technology. The information may be computer-readable instructions, data structures, modules of a program, or other data. Examples of computer-readable storage media 42 include but are not limited to: phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device.

[0123] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0124] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A control method for a dual-motor hybrid system of a hybrid vehicle, characterized in that: The dual-motor hybrid system includes an engine, a first motor, a second motor, a transmission and a clutch, wherein the first motor is drivingly connected to the engine, the input shaft of the transmission is connected to the engine, the first motor and the second motor, and the clutch is connected to the second motor and the first motor respectively; The method comprises: When the dual-motor hybrid system is in a parallel mode, obtaining an input shaft request torque and a first motor request torque; In response to the input shaft requested torque being greater than the torque capacity of the clutch, and the difference between the input shaft requested torque and the torque capacity of the clutch being less than the speed regulation intervention torque capacity of the input shaft, the first motor is controlled to output the sum of the first motor requested torque and the intervention negative torque, and the engine is controlled to output the engine torque; wherein the absolute value of the intervention negative torque is less than or equal to the difference between the input shaft requested torque and the torque capacity of the clutch; the engine torque is a positive torque, which is equal to the difference between the torque capacity of the clutch and the intervention negative torque; and the torque capacity of the clutch is the maximum torque that the clutch can transmit.

2. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 1, characterized in that: The controlling the first motor to output the sum of the first motor request torque and the intervention negative torque, and controlling the engine to output the engine torque, comprises: The first motor is controlled to output a sum of the first motor request torque and a maximum intervention negative torque that can be output by the first motor; and the engine torque is equal to a difference between the torque capacity of the clutch and the maximum intervention negative torque.

3. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 2, characterized in that: After controlling the engine to output engine torque, the method includes: In response to the sum of the engine torque output by the engine and the maximum intervention negative torque being less than the input shaft request torque, the second motor is controlled to output a second motor torque, wherein the sum of the second motor torque, the engine torque and the maximum intervention negative torque that the first motor can output is equal to the input shaft request torque.

4. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 1, characterized in that: The method further comprises: When the hybrid vehicle is in a power upshift mode, in response to a gear shift speed regulation request in this mode, a second motor request torque is obtained, and a speed regulation intervention torque of the input shaft is determined according to the gear shift speed regulation request; In response to the speed intervention torque being less than or equal to the speed intervention torque capacity of the second electric machine, the second electric machine is controlled to output a sum of the speed intervention torque and a second electric machine request torque.

5. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 4, characterized in that: The method comprises: In response to the speed intervention torque being greater than the speed intervention torque capacity of the second motor and less than or equal to the speed intervention torque capacity of the input shaft, the second motor is controlled to output the sum of the speed intervention torque capacity of the second motor and the second motor requested torque, and the first motor and / or the engine are controlled to output a remaining intervention torque, wherein the remaining intervention torque is the difference between the speed intervention torque and the speed intervention torque capacity of the second motor.

6. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 5, characterized in that: The hybrid vehicle includes a battery, the first motor is electrically connected to the battery, and the controlling the first motor and / or the engine to output the remaining intervention torque includes: Obtaining the negative power capacity of the battery; In response to the negative power capacity being less than or equal to a negative power capacity threshold, the first motor is controlled to output a first motor intervention torque; the first motor intervention torque is less than or equal to the remaining intervention torque, and the first motor intervention torque is a positive torque or a negative torque.

7. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 6, characterized in that: The controlling the first motor and / or the engine to output the remaining intervention torque comprises: In response to the negative power capacity being less than or equal to a negative power capacity threshold and the remaining intervention torque being less than or equal to the speed regulation intervention torque capacity of the first motor, the first motor is controlled to output the first motor intervention torque, and the first motor intervention torque is equal to the remaining intervention torque.

8. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 6, characterized in that: The controlling the first motor and / or the engine to output the remaining intervention torque comprises: In response to the negative power capacity being less than or equal to a negative power capacity threshold and the remaining intervention torque being greater than the speed intervention torque capacity of the first motor, the first motor is controlled to output the speed intervention torque capacity of the first motor, and the engine is controlled to output an engine intervention torque, wherein the engine intervention torque is equal to a difference between the remaining intervention torque and the speed intervention torque capacity of the first motor.

9. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 6, characterized in that: After obtaining the negative power capacity of the battery, the method further includes: In response to the negative power capacity being greater than the negative power capacity threshold, the torque output by the first motor is reduced within a positive torque interval.

10. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 9, characterized in that: After obtaining the negative power capacity of the battery, the method further includes: In response to the negative power capacity being greater than the negative power capacity threshold and the positive torque output by the first motor being less than the remaining intervention torque, the engine is controlled to output an engine intervention torque, the engine intervention torque being equal to The difference between the residual intervention torque and the positive torque output by the first electric machine.

11. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 6, characterized in that: The clutch comprises a shift clutch that is engaged when the hybrid vehicle is in the power upshift mode; the method further comprises: In response to the speed intervention torque being greater than the speed intervention torque capacity of the input shaft, the second motor is controlled to output the sum of the speed intervention torque capacity of the second motor and the second motor requested torque, the engine is controlled to output the speed intervention torque capacity of the engine, and according to the negative power capacity of the battery, the first motor is controlled, and according to the difference between the speed intervention torque and the speed intervention torque capacity of the input shaft, the shift clutch output torque is controlled.

12. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 11, characterized in that: The step of controlling the output torque of the shift clutch according to the difference between the speed regulation intervention torque and the speed regulation intervention torque capacity of the input shaft comprises: determining an adjustment torque according to a series / parallel mode, a shift mode, a gear position, a target speed change rate of the input shaft, and an actual speed change rate of the input shaft of the dual-motor hybrid system; determining an output torque of the shift clutch according to a difference between the speed regulation intervention torque and the speed regulation intervention torque capacity of the input shaft, a feedforward torque of the clutch, and the regulating torque; The shifting clutch is controlled to output the output torque.

13. The control method of the dual-motor hybrid system of a hybrid vehicle according to claim 1, characterized in that: The speed intervention torque capacity of the input shaft is the sum of the speed intervention torque capacity of the first motor, the speed intervention torque capacity of the second motor, and the speed intervention torque capacity of the engine.

14. A computer-readable storage medium, characterized in that: It comprises one or more processors for executing the control method of the dual-motor hybrid system of the hybrid electric vehicle as described in any one of claims 1-13.

15. A control device for a dual-motor hybrid system of a hybrid vehicle, characterized in that: It comprises one or more processors for executing the control method of the dual-motor hybrid system of the hybrid electric vehicle as described in any one of claims 1-13.

16. A hybrid vehicle, characterized in that: include: A dual-motor hybrid system includes an engine, a first motor, a second motor, a transmission and a clutch, wherein the first motor is drivingly connected to the engine, an input shaft of the transmission is connected to the engine, the first motor and the second motor, and the clutch is connected to the second motor and the first motor respectively; and The control device of the dual-motor hybrid system of the hybrid vehicle as claimed in claim 15 is electrically connected to the dual-motor hybrid system.

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