Hybrid power transmission hydraulic system, control method thereof and vehicle

Abstract

The invention provides a hybrid power transmission hydraulic system, a control method thereof and a vehicle, and relates to the technical field of transmissions.The hydraulic system comprises a first oil pump, a first oil pump motor, a second oil pump, a second oil pump motor, a switch valve and a controller; the controller controls the switching position of the switching valve and determines the target rotating speed of the first oil pump motor and the target rotating speed of the second oil pump motor according to the total flow demand of the first oil pump, the connection state demand of the clutch and the torque demand of the clutch, so that the two oil pumps of the hydraulic system are more reasonably controlled; and the requirements on oil pump flow in different running states of the vehicle are met.

Description

Technical Field

[0001] The present invention relates to the technical field of transmissions, and in particular to a hybrid transmission hydraulic system, a control method thereof, and a vehicle. Background Art

[0002] The hybrid transmission is a core component of hybrid vehicles, coordinating power transfer between the engine, generator, and battery to achieve efficient energy management. The basic structure of a hybrid transmission primarily consists of a clutch and a hydraulic system. The clutch engages and disengages engine power, while the hydraulic system controls clutch engagement and disengagement, cools the clutch, the drive motor, and the generator.

[0003] In the related art, the hydraulic system usually adopts two independent oil pumps, a low-pressure, high-flow oil pump for cooling the clutch, drive motor and generator, and a high-pressure, low-flow oil pump for controlling the engagement and disengagement of the clutch. The flow requirements of the two oil pumps are different in different operating states of hybrid vehicles. For example, in some operating states, the flow demand for the low-pressure, high-flow oil pump of the hybrid vehicle is large, which has exceeded the maximum flow limit of the oil pump. In other operating states, the flow demand for the low-pressure, high-flow oil pump of the hybrid vehicle is small. Therefore, the design of two independent oil pumps in the related art cannot meet the flow requirements of the oil pump under different operating states of the vehicle. Summary of the Invention

[0004] The problem solved by the present invention is how to more reasonably control the two oil pumps of the hydraulic system to meet the demand for oil pump flow under different operating states of the vehicle.

[0005] In order to solve the above problems, the present invention provides a hybrid transmission hydraulic system and a control method thereof, a vehicle In a first aspect, the present invention provides a hybrid transmission hydraulic system, comprising: a first oil pump and a first oil pump motor, wherein the first oil pump motor is used to drive the first oil pump, and the first oil pump is used to provide cooling oil to a cooling oil circuit in the hybrid transmission; a second oil pump and a second oil pump motor, the second oil pump motor being used to drive the second oil pump, the second oil pump being used at least to control engagement or disengagement of a clutch in the hybrid transmission; an on-off valve, wherein an oil inlet of the on-off valve is connected to the second oil pump, and an oil outlet of the on-off valve is used to be connected to the clutch or to be connected to the clutch and the cooling oil circuit, and the on-off valve is used to control the communication between the second oil pump and the clutch or between the clutch and the cooling oil circuit by switching its switch position; A controller configured to: Obtaining a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch; wherein the connection state requirement of the clutch is a connection state that the clutch currently needs to switch to; Controlling the switching of the switch position of the switch valve according to the total flow requirement of the first oil pump and the connection state requirement of the clutch; and A target speed of the first oil pump motor and a target speed of the second oil pump motor are determined according to a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch.

[0006] Optionally, the cooling oil circuit includes cooling oil circuits for the drive motor, the generator, and the clutch, and obtaining the total flow requirement of the first oil pump includes: Acquiring the temperature of the drive motor, the temperature of the generator, and the temperature of the clutch; determining a flow rate requirement of the drive motor according to a temperature of the drive motor; determining a flow requirement of the generator according to a temperature of the generator; determining a flow requirement of the clutch according to a temperature of the clutch; The total flow requirement of the first oil pump is determined according to the flow requirement of the drive motor, the flow requirement of the generator, and the flow requirement of the clutch.

[0007] Optionally, determining the total flow requirement of the first oil pump according to the flow requirement of the drive motor, the flow requirement of the generator, and the flow requirement of the clutch includes: determining a first flow requirement of the first oil pump according to a flow requirement of the drive motor; determining a second flow requirement of the first oil pump according to the flow requirement of the generator; determining a third flow requirement of the first oil pump according to the flow requirement of the clutch; A total flow requirement of the first oil pump is determined according to the first flow requirement, the second flow requirement, and the third flow requirement.

[0008] Optionally, determining the total flow requirement of the first oil pump according to the first flow requirement, the second flow requirement, and the third flow requirement includes: The largest flow demand among the first flow demand, the second flow demand, and the third flow demand is used as the total flow demand of the first oil pump.

[0009] Optionally, the switching valve has a first switching position and a second switching position. When the switching valve is in the first switching position, the second oil pump is connected to the clutch. When the switching valve is in the second switching position, the second oil pump is simultaneously connected to the clutch and the cooling oil circuit.

[0010] Optionally, controlling the switching of the switch position of the switch valve according to the total flow requirement of the first oil pump and the connection state requirement of the clutch includes: When the connection state requirement of the clutch is switching from a disengaged state to an engaged state, or when the connection state requirement of the clutch is an engaged state and the total flow demand of the first oil pump is less than or equal to the upper limit flow of the first oil pump, controlling the switching valve to be in a first switching position to connect the second oil pump to the clutch; When the connection state requirement of the clutch is the engaged state and the total flow demand of the first oil pump is greater than the upper limit flow of the first oil pump, the switching valve is controlled to be in the second switching position so that the second oil pump is connected to both the clutch and the cooling oil circuit.

[0011] Optionally, determining the target speed of the first oil pump motor and the target speed of the second oil pump motor according to the total flow requirement of the first oil pump, the connection state requirement of the clutch, and the torque requirement of the clutch includes: When the clutch connection state requirement is a disengaged state, the target speed of the first oil pump motor is the product of the total flow requirement of the first oil pump and the first speed coefficient, and the target speed of the second oil pump motor is 0; When the connection state requirement of the clutch is switching from a disengaged state to an engaged state, or when the connection state requirement of the clutch is an engaged state and the total flow demand of the first oil pump is less than or equal to the upper limit flow rate of the first oil pump, the target speed of the first oil pump motor is the product of the total flow demand of the first oil pump and a first speed coefficient, and the target speed of the second oil pump motor is the product of the torque requirement of the clutch and the second speed coefficient; When the clutch connection state requirement is an engaged state and the total flow demand of the first oil pump is greater than the upper limit flow of the first oil pump, the target speed of the first oil pump motor is the product of the upper limit flow of the first oil pump and the first speed coefficient, and the target speed of the second oil pump motor is determined according to the following method: determining a flow regulation deviation according to a total flow demand of the first oil pump and an upper flow limit of the first oil pump; determining a first speed of the second oil pump motor according to the flow regulation deviation; The maximum value of the first rotation speed of the second oil pump motor and the rotation speed required when the clutch is engaged is used as the target rotation speed of the second oil pump motor.

[0012] Optionally, the switch valve is a solenoid valve.

[0013] In a second aspect, the present invention provides a control method for a hybrid transmission hydraulic system, the hydraulic system comprising a first oil pump, a first oil pump motor, a second oil pump, a second oil pump motor, and a switch valve, wherein an oil inlet of the switch valve is connected to the second oil pump, an oil outlet of the switch valve is used to connect to the clutch and / or the cooling oil circuit, and the switch valve is used to control the second oil pump to connect to the clutch and / or the cooling oil circuit; wherein the control method comprises: obtaining a total flow requirement of the first oil pump, obtaining a connection state requirement of the clutch, and obtaining a torque requirement of the clutch; controlling the switch position of the switch valve according to the total flow requirement of the first oil pump and the connection state requirement of the clutch; and A target speed of the first oil pump motor and a target speed of the second oil pump motor are determined according to a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch.

[0014] In a third aspect, the present invention provides a vehicle comprising a hybrid transmission hydraulic system, wherein the hybrid transmission hydraulic system is the hybrid transmission hydraulic system described in any one of the first aspects above.

[0015] The hybrid transmission hydraulic system, control method thereof, and vehicle of the present invention have the following beneficial effects: the hydraulic system includes: a first oil pump, a first oil pump motor, a second oil pump, a second oil pump motor, an on-off valve, and a controller; the first oil pump motor is used to drive the first oil pump, which is used to provide cooling oil to a cooling oil circuit in the hybrid transmission; the first oil pump and the first oil pump motor are used to drive the first oil pump, which is used to provide cooling oil to the cooling oil circuit in the hybrid transmission; the second oil pump motor is used to drive the second oil pump, which is used to control at least the engagement or disengagement of a clutch in the hybrid transmission; an oil inlet of the on-off valve is connected to the second oil pump; an oil outlet of the on-off valve is connected to the clutch and / or the cooling oil circuit; the on-off valve is used to control the communication of the second oil pump with the clutch and / or the cooling oil circuit; the on-off valve is used to switch the on-off position of the on-off valve so that the second oil pump can be connected only to the clutch or to both the clutch and the cooling oil circuit, thereby enabling the second oil pump to control the clutch alone or simultaneously control the clutch and provide cooling oil to the cooling oil circuit. The controller is configured to obtain the total flow demand of the first oil pump, the clutch connection state, and the clutch torque demand, and to obtain the first oil pump flow demand, clutch connection state, and clutch torque demand under different vehicle operating states to provide data support for subsequently controlling the switching position of the switch valve, the target speed of the first oil pump motor, and the target speed of the second oil pump under different vehicle operating states. By controlling the switching position of the switch valve based on the total flow demand of the first oil pump and the clutch connection state, when the total flow demand of the first oil pump is high, the switch position of the switch valve can be controlled to simultaneously supply cooling oil to the cooling oil circuit by controlling the switch position of the switch valve. When the total flow demand of the first oil pump is low, the switch position of the switch valve can be controlled to supply cooling oil to the cooling oil circuit only by the first oil pump. The target speed of the first oil pump motor and the target speed of the second oil pump motor are determined according to the total flow demand of the first oil pump, the connection status of the clutch and the torque demand of the clutch. Different target speeds of the first oil pump motor and the second oil pump motor can be determined in combination with different operating states of the vehicle to accurately provide the required flow to the cooling oil circuit and / or the clutch, thereby more reasonably controlling the two oil pumps of the hydraulic system to meet the oil pump flow demand under different operating states of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of a hybrid transmission in related technology; Figure 2 A schematic structural diagram of a hybrid transmission hydraulic system according to an embodiment of the present invention; Figure 3 A flow chart of a control method for a hybrid transmission hydraulic system according to an embodiment of the present invention; Figure 4 A flowchart of obtaining the total flow demand of the first oil pump according to an embodiment; Figure 5 A flowchart of determining the total flow requirement of the first oil pump according to an embodiment; Figure 6 A flow chart for switching the switch position of a control switch valve according to an embodiment; Figure 7 A flowchart of determining a target speed of a first oil pump motor and a target speed of a second oil pump motor according to an embodiment.

[0017] Description of reference numerals: Hydraulic system 100; first oil pump 101; first oil pump motor 102; second oil pump 103; second oil pump motor 104; oil pan 105; filter 106; switch valve 107; Hybrid system 200; clutch 201; first shaft 202; second shaft 203; Cooling oil circuit 300; cooling oil circuit 301 of the clutch; cooling oil circuit 302 of the generator; cooling oil circuit 303 of the drive motor. DETAILED DESCRIPTION

[0018] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein. Instead, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0019] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0020] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to"; the term "based on" means "based at least in part on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiments". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc. mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0021] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0022] The names of the messages or information exchanged between multiple devices in the embodiments of the present invention are only used for illustrative purposes and are not used to limit the scope of these messages or information.

[0023] In related technologies, such as Figure 1As shown, the hybrid transmission includes a hydraulic system 100, a hybrid system 200, and a cooling oil circuit 300. The hybrid system 200 includes a drive motor (not shown), a generator (not shown), and a clutch 201. The clutch 201 has a first shaft 202 connecting the vehicle engine and the generator, and a second shaft 203 connecting the transmission gears. The clutch 201 has two connection states: engaged and disengaged. When the clutch 201 is disengaged, the engine and generator are directly connected, the engine drives the generator to generate electricity, and the generated electricity is output to the drive motor, so that the drive motor drives the vehicle. When the clutch 201 is engaged, the engine and generator are disconnected, and the engine and drive motor are connected in parallel to drive the vehicle simultaneously. The cooling oil circuit 300 includes at least the cooling oil circuit 301 for the clutch 201, the cooling oil circuit 302 for the generator, and the cooling oil circuit 303 for the drive motor. In some embodiments, it may also include cooling oil circuits for some shafts in the hybrid system 200. The hydraulic system 100 may include: a first oil pump 101, a first oil pump motor 102, a second oil pump 103, a second oil pump motor 104, an oil pan 105 and a filter 106. The first oil pump motor 102 is used to drive the first oil pump 101. The first oil pump 101 is used to provide cooling oil to the cooling oil circuit 300. The first oil pump 101 pumps cooling oil from the oil pan 105 through the filter 106 to provide cooling oil to the cooling oil circuit 300. The second oil pump motor 104 is used to drive the second oil pump 103. The second oil pump 103 is used to control the engagement or disengagement of the clutch 201. The second oil pump 103 pumps hydraulic oil from the oil pan 105 through the filter 106 and realizes smooth engagement and disengagement of the clutch 201 through pressure transmission of the hydraulic oil. In one embodiment, the clutch 201 is in a disengaged state in an initial state. The second oil pump 103 can switch the clutch 201 from the disengaged state to the engaged state by pumping hydraulic oil.

[0024] The second oil pump 103 in the above-mentioned hydraulic system 100 is only connected to the clutch 201, and the first oil pump is also only connected to the cooling oil circuit 300. The two are independent of each other. As the vehicle's operating state changes, the cooling oil flow required by the cooling oil circuit 300 will change accordingly, which will cause the total flow demand of the first oil pump 101 to change as well. When the total flow demand of the first oil pump 101 exceeds the upper limit flow of the first oil pump 101, the first oil pump 101 will not be able to meet the flow demand of the cooling oil circuit 300, and thus cannot ensure that the hybrid system 200 can operate within a safe temperature range.

[0025] In response to the above problems, embodiments of the present invention provide a hybrid transmission hydraulic system, a control method thereof, and a vehicle.

[0026] like Figure 2As shown, an embodiment of the present invention provides a hybrid transmission hydraulic system, in the above Figure 1 On the basis of , the hydraulic system 100 further includes: a switch valve 107 and a controller (not shown in the figure).

[0027] The oil inlet of the switch valve 107 is connected to the second oil pump 103, and the oil outlet of the switch valve 107 is used to be connected to the clutch 201 or to be connected to the clutch 201 and the cooling oil circuit 300 at the same time. The switch valve 107 is used to control the second oil pump 103 to be connected to the clutch 201 or to be connected to the clutch 201 and the cooling oil circuit 300 at the same time by switching its switch position.

[0028] Specifically, the second oil pump 103 can be connected only to the clutch 201 by controlling the switch position of the switching valve 107 , or the second oil pump 103 can be connected to the clutch 201 and the cooling oil circuit 300 at the same time.

[0029] Specifically, in the initial state, the switching position of the switching valve 107 is that the second oil pump 103 is only connected to the clutch 201, so as to control the clutch 201 to engage or disengage when needed; when the total flow demand of the first oil pump 101 exceeds the upper limit flow of the first oil pump 101, even if the first oil pump 101 works at its upper limit flow, it cannot meet the flow demand of the cooling oil circuit 300. At this time, the switching position of the switching valve 107 can be controlled to make the second oil pump 103 connected to the clutch 201 and the cooling oil circuit 300 at the same time. While normally controlling the clutch 201 to engage or disengage, it can also serve as an auxiliary oil pump to provide cooling oil to the cooling oil circuit 300 to meet the flow demand of the cooling oil circuit 300.

[0030] The controller can be implemented as software, hardware, firmware, or any combination thereof, and can use one or more application-specific integrated circuits (ASICs), one or more general-purpose integrated circuits, one or more microprocessors, one or more programmable logic devices, or any combination of the aforementioned circuits and / or devices, or other suitable circuits or devices. In addition, the controller 108 can control the hydraulic system 100 to perform the corresponding steps of the methods in various embodiments of the present specification, such as Figure 3 As shown, it may include: S310 : Obtaining the total flow requirement of the first oil pump 101 , obtaining the connection state requirement of the clutch 201 , and obtaining the torque requirement of the clutch 201 .

[0031] Specifically, the total flow demand of the first oil pump 101 is related to the flow demand of the cooling oil circuit 300, and the cooling oil circuit 300 mainly includes the cooling oil circuit 301 of the clutch 201, the cooling oil circuit 302 of the generator and the cooling oil circuit 303 of the drive motor. The flow demands of the cooling oil circuit 301 of the clutch 201, the cooling oil circuit 302 of the generator and the cooling oil circuit 303 of the drive motor are respectively related to their respective temperatures. Therefore, the flow demands of the cooling oil circuit 301 of the clutch 201, the cooling oil circuit 302 of the generator and the cooling oil circuit 303 of the drive motor can be determined by the temperature of the clutch 201, the temperature of the generator and the temperature of the drive motor, thereby obtaining the total flow demand of the first oil pump 101.

[0032] Specifically, the connection states of clutch 201 include a disengaged state, an engaged state, and the process of switching from the disengaged state to the engaged state. The connection state requirement of clutch 201 is the connection state that clutch 201 currently needs to switch to, which can be determined by the vehicle's driving mode. For example, for a hybrid vehicle, in pure electric mode, clutch 201 is in a disengaged state. In hybrid mode, at low speeds, clutch 201 is in the process of switching from the disengaged state to the engaged state or in a disengaged state. During acceleration / high speeds, clutch 201 is in an engaged state.

[0033] Specifically, the torque demand of the clutch 201 is the torque corresponding to the pressure required by the clutch 201 when it is engaged.

[0034] It should be noted that the above-mentioned information can be obtained through the main control system of the car.

[0035] S320 : Controlling the switching position of the on-off valve 107 according to the total flow requirement of the first oil pump 101 and the connection state requirement of the clutch 201 .

[0036] Specifically, according to the switching position switching of the switching valve 107 , the connection between the second oil pump 103 and the clutch 201 or the connection between the second oil pump 103 and the clutch 201 and the cooling oil circuit 300 can be switched by switching the switching position of the switching valve 107 . In one embodiment, when the total flow demand of the first oil pump 101 is less than or equal to the upper limit flow of the first oil pump 101 and the clutch 201 needs to be engaged, the switch position of the switch valve 107 is controlled to switch so that the second oil pump 103 is connected to the clutch 201. At this time, the second oil pump 103 is not required to serve as an auxiliary oil pump to replenish cooling oil for the first oil pump 101; in another embodiment, when the total flow demand of the first oil pump 101 exceeds the upper limit flow of the first oil pump 101 and the clutch 201 needs to be engaged, the switch position of the switch valve 107 is controlled to switch so that the second oil pump 103 is connected to the clutch 201 and the cooling oil circuit 300 at the same time. At this time, the second oil pump 103 can both control the engagement of the clutch 201 and serve as an auxiliary oil pump to replenish cooling oil for the first oil pump 101.

[0037] S330 : Determine a target speed of the first oil pump motor 102 and a target speed of the second oil pump motor 104 according to the total flow requirement of the first oil pump 101 , the connection state requirement of the clutch 201 , and the torque requirement of the clutch 201 .

[0038] Specifically, the actual pumping oil flow rates of the first oil pump 101 and the second oil pump 103 are respectively related to the rotational speed of the first oil pump motor 102 and the rotational speed of the second oil pump motor 104 that drive them. Taking the first oil pump 101 as an example, when the rotational speed of the first oil pump motor 102 is relatively high, the corresponding pumping oil flow rate of the first oil pump 101 also increases accordingly. Therefore, the total flow rate requirement of the first oil pump 101, the connection state requirement of the clutch 201 and the torque requirement of the clutch 201 in this embodiment can determine the target rotational speed of the first oil pump motor 102 and the target rotational speed of the second oil pump motor 104, so as to accurately control the actual pumping oil flow rates of the first oil pump 101 and the second oil pump 103, which can not only meet the flow rate requirement of the cooling oil circuit 300, but also normally control the engagement and disengagement of the clutch 201.

[0039] In this embodiment, the hydraulic system includes: a first oil pump, a first oil pump motor, a second oil pump, a second oil pump motor, an on-off valve, and a controller. The first oil pump motor is configured to drive the first oil pump, which is configured to provide cooling oil to a cooling oil circuit in a hybrid transmission. The first oil pump and the first oil pump motor are configured to drive the first oil pump, which is configured to provide cooling oil to the cooling oil circuit in the hybrid transmission. The second oil pump motor is configured to drive the second oil pump, which is configured to at least control the engagement or disengagement of a clutch in the hybrid transmission. The oil inlet of the on-off valve is connected to the second oil pump. The oil outlet of the on-off valve is configured to communicate with the clutch and / or the cooling oil circuit. The on-off valve is configured to control the communication of the second oil pump with the clutch and / or the cooling oil circuit. The on-off valve can be switched to a different position to connect the second oil pump to only the clutch or to both the clutch and the cooling oil circuit, enabling the second oil pump to control the clutch alone or to simultaneously control the clutch and provide cooling oil to the cooling oil circuit. The controller is configured to obtain the total flow demand of the first oil pump, the clutch connection state, and the clutch torque demand. The controller obtains the first oil pump flow demand, clutch connection state, and clutch torque demand under different vehicle operating states to provide data support for subsequently controlling the switching position of the switch valve, the target speed of the first oil pump motor, and the target speed of the second oil pump under different vehicle operating states. The controller controls the switching position of the switch valve based on the total flow demand of the first oil pump and the clutch connection state. When the total flow demand of the first oil pump is high, the switch position of the switch valve is controlled so that the first and second oil pumps simultaneously supply cooling oil to the cooling oil circuit. When the total flow demand of the first oil pump is low, the switch position of the switch valve is controlled so that only the first oil pump supplies cooling oil to the cooling oil circuit. The target speed of the first oil pump motor and the target speed of the second oil pump motor are determined according to the total flow demand of the first oil pump, the connection status of the clutch and the torque demand of the clutch. Different target speeds of the first oil pump motor and the second oil pump motor can be determined in combination with different operating states of the vehicle to accurately provide the required flow to the cooling oil circuit and / or the clutch, thereby more reasonably controlling the two oil pumps of the hydraulic system to meet the oil pump flow demand under different operating states of the vehicle.

[0040] Alternatively, as Figure 4 As shown, obtaining the total flow demand of the first oil pump 101 includes the following steps: S410 : Acquire the temperature T_P3 of the drive motor, the temperature of the generator T_P1 , and the temperature T_C of the clutch 201 .

[0041] Specifically, the above temperatures are the temperatures of the drive motor, generator and clutch at the current moment, which are acquired from temperature sensors provided at various components by the main control system of the vehicle.

[0042] S420: Determine the flow requirement of the drive motor according to the temperature of the drive motor.

[0043] Specifically, the flow demand of the drive motor Flow_P3=A3*T_P3, where Flow_P3 is the flow demand of the drive motor, A3 is a coefficient, and T_P3 is the temperature of the drive motor.

[0044] S430: Determine the flow requirement of the generator according to the temperature of the generator.

[0045] Specifically, the flow demand of the generator Flow_P1=A1*T_P1, where Flow_P1 is the flow demand of the generator, A1 is a coefficient, and T_P1 is the temperature of the generator.

[0046] S440 : Determine the flow requirement of the clutch 201 according to the temperature of the clutch 201 .

[0047] Specifically, the flow demand of the clutch 201 is Flow_C=AC*T_C, where Flow_C is the flow demand of the clutch 201 , AC is a coefficient, and T_C is the temperature of the clutch 201 .

[0048] It should be noted that the values ​​of coefficient A3, coefficient A1 and coefficient AC can be obtained through technical personnel's experience or multiple tests, or can be determined through deep learning and other methods.

[0049] S450 : Determine the total flow requirement of the first oil pump 101 according to the flow requirement of the drive motor, the flow requirement of the generator, and the flow requirement of the clutch 201 .

[0050] In this optional embodiment, based on the current temperatures of the drive motor, generator and clutch 201 that need to be cooled in the cooling oil circuit 300, the flow rates of cooling oil required for the drive motor, generator and clutch 201 are determined, and the total flow rate requirement of the first oil pump 101 is determined based on the flow rate requirement of the drive motor, the flow rate requirement of the generator and the flow rate requirement of the clutch 201, so as to accurately determine the total flow rate requirement of the first oil pump and avoid the first oil pump 101 pumping too much or too little cooling oil.

[0051] Alternatively, as Figure 5 As shown, determining the total flow requirement of the first oil pump 101 according to the flow requirement of the drive motor, the flow requirement of the generator and the flow requirement of the clutch 201 includes the following steps: S510 : Determine a first flow requirement of the first oil pump 101 according to the flow requirement of the driving motor.

[0052] Specifically, the first flow demand of the first oil pump 101 is Flow_Tot_P3 = Flow_P3 / B3, where Flow_Tot_P3 is the first flow demand, Flow_P3 is the flow demand of the driving motor, and B3 is a coefficient.

[0053] S520: Determine a second flow requirement of the first oil pump 101 according to the flow requirement of the generator.

[0054] Specifically, the second flow demand of the first oil pump 101 is Flow_Tot_P1 = Flow_P1 / B1 , where Flow_Tot_P1 is the second flow demand, Flow_P1 is the flow demand of the generator, and B1 is a coefficient.

[0055] S530 : Determine a third flow requirement of the first oil pump 101 according to the flow requirement of the clutch 201 .

[0056] Specifically, the third flow demand of the first oil pump 101 is Flow_Tot_C=Flow_C / BC, where Flow_Tot_C is the third flow demand, Flow_C is the flow demand of the clutch 201, BC is a coefficient, and B1+B3+BC=1.

[0057] It should be noted that the values ​​of coefficient B3, coefficient B1 and coefficient BC can be obtained through technical personnel's experience or multiple tests, or can be determined through deep learning and other methods.

[0058] S540: Determine a total flow requirement of the first oil pump according to the first flow requirement, the second flow requirement, and the third flow requirement.

[0059] In some embodiments, the largest flow demand among the first flow demand, the second flow demand and the third flow demand can be used as the total flow demand of the first oil pump 101, that is, the flow that meets the largest flow demand can also meet other flow demands. The specific expression is Flow_Lo=Max(Flow_Tot_P1, Flow_Tot_P3, Flow_Tot_C), Flow_Lo is the total flow demand of the first oil pump, Flow_Tot_P1 is the second flow demand, Flow_Tot_P3 is the first flow demand, and Flow_Tot_C is the third flow demand.

[0060] In this optional embodiment, based on the flow demand of the drive motor, the flow demand of the generator and the flow demand of the clutch 201, the total flow demand of the corresponding first oil pump 101 is determined respectively, and then the largest flow demand among the three total flow demands is determined as the final total flow demand to simultaneously meet the flow demands of the drive motor, the generator and the clutch.

[0061] Optionally, the switch valve 107 has a first switch position and a second switch position. When the switch valve 107 is in the first switch position, the second oil pump 103 is connected to the clutch 201. When the switch valve 107 is in the second switch position, the second oil pump 103 is connected to the clutch 201 and the cooling oil circuit 300 at the same time.

[0062] In some embodiments, in an initial state, the switch valve 107 is in a first switch position by default. When switching is required, the switch valve 107 is switched from the first switch position to the second switch position.

[0063] like Figure 6 As shown, according to the total flow requirement of the first oil pump 101 and the connection state requirement of the clutch 201, controlling the switching position of the switching valve 107 includes the following steps: S610: When the connection state requirement of the clutch 201 is to switch from the disengaged state to the engaged state, or when the connection state requirement of the clutch 201 is the engaged state and the total flow requirement of the first oil pump 101 is less than or equal to the upper limit flow of the first oil pump 101, the switch valve 107 is controlled to be in the first switch position to connect the second oil pump 103 to the clutch 201.

[0064] Specifically, the clutch 201 is in a disengaged state in the initial state. After the second oil pump 103 provides hydraulic oil to the clutch 201 to apply pressure to the clutch 201, the clutch 201 switches from the disengaged state to the engaged state. The hydraulic oil provided by the second oil pump 103 is used to press the clutch 201 to put it in an engaged state. Therefore, when the connection state requirement of the clutch 201 is a disengaged state, the second oil pump 103 does not need to provide hydraulic oil to the clutch 201. At this time, the switching position of the switch valve 107 can be in any position, that is, there is no need to control the switch position switching of the switch valve 107.

[0065] Specifically, when the connection state requirement of the clutch 201 is to switch from the disengaged state to the engaged state, or when the connection state requirement of the clutch 201 is the engaged state and the total flow demand of the first oil pump 101 is less than or equal to the upper limit flow of the first oil pump 101, on the one hand, the second oil pump 103 is required to provide hydraulic oil to the clutch 201 to engage the clutch 201, and on the other hand, the total flow demand of the first oil pump 101 does not exceed the upper limit flow of the first oil pump 101, and the first oil pump 101 alone can be relied upon to provide cooling oil to the cooling oil circuit 300. Therefore, the switch valve 107 is controlled to be in the first switch position to connect the second oil pump 103 to the clutch 201.

[0066] S620: When the connection state requirement of the clutch 201 is the engaged state and the total flow demand of the first oil pump 101 is greater than the upper limit flow of the first oil pump 101, the switch valve 107 is controlled to be in the second switch position so that the second oil pump 103 is connected to the clutch 201 and the cooling oil circuit 300.

[0067] Specifically, when the connection state requirement of the clutch 201 is the engaged state and the total flow demand of the first oil pump 101 is greater than the upper limit flow of the first oil pump 101, on the one hand, the second oil pump 103 is required to provide hydraulic oil for the clutch 201 to engage the clutch 201, and on the other hand, the total flow demand of the first oil pump 101 exceeds the upper limit flow of the first oil pump 101. The first oil pump 101 cannot meet the total flow demand and needs to be assisted by the second oil pump 103. Therefore, the control switch valve 107 is in the first switch position to make the second oil pump 103 connected to the clutch 201 and the cooling oil circuit 300 at the same time.

[0068] In some embodiments, the switch valve 107 can be a solenoid valve, which is in a first switch position when not powered and switches to a second switch position when powered. That is, when the switch valve 107 needs to be in the first switch position, the switch valve 107 can be controlled to be de-energized. When the switch valve 107 needs to be switched to the second switch position, the switch valve 107 can be controlled to be energized.

[0069] In this optional embodiment, based on the connection status requirement of the clutch 201 and the relationship between the total flow requirement of the first oil pump 101 and the upper limit flow of the first oil pump 101, it is determined whether the second oil pump 103 is only connected to the clutch 201, or the second oil pump 103 is simultaneously connected to the clutch 201 and the cooling oil circuit 300, thereby determining the switching position of the switching valve 107, so that under different circumstances, the connection switching requirement of the clutch 201 and the total flow requirement of the first oil pump 101 can be met at the same time.

[0070] Alternatively, as Figure 7 As shown, determining the target speed of the first oil pump motor 102 and the target speed of the second oil pump motor 104 based on the total flow requirement of the first oil pump 101, the connection state requirement of the clutch 201, and the torque requirement of the clutch 201 includes the following steps: S710 : When the connection state requirement of the clutch 201 is the disengaged state, the target speed of the first oil pump motor 102 is the product of the total flow requirement of the first oil pump and the first speed coefficient, and the target speed of the second oil pump motor 104 is 0.

[0071] Specifically, the target speed N_PmpLo of the first oil pump motor 102 = C*Flow_Lo, where N_PmpLo is the target speed of the first oil pump motor 102 , C is the first speed coefficient, and Flow_Lo is the total flow requirement of the first oil pump.

[0072] Specifically, as mentioned above, when the connection state requirement of the clutch 201 is the disengagement state, the second oil pump 103 is not required to provide hydraulic oil to form engagement pressure for the clutch 201 , and therefore, the target speed of the second oil pump motor 104 is 0.

[0073] S720: When the connection state requirement of the clutch 201 is to switch from the disengaged state to the engaged state, or when the connection state requirement of the clutch 201 is the engaged state and the total flow demand of the first oil pump 101 is less than or equal to the upper limit flow of the first oil pump 101, the target speed of the first oil pump motor 102 is the product of the total flow demand of the first oil pump 101 and the first speed coefficient, and the target speed of the second oil pump motor 104 is the product of the torque demand of the clutch 201 and the second speed coefficient.

[0074] Specifically, similar to S710 , the target rotation speed N_PmpLo of the first oil pump motor 102 is equal to C*Flow_Lo.

[0075] Specifically, the target speed of the second oil pump motor 104 is N_PmpC=E*P_C, where N_PmpC is the target speed of the second oil pump motor 104, P_C is the required pressure for engagement of the clutch 201, the P_C number is D*Tq_C, Tq_C is the torque requirement of the clutch 201, D and E are both coefficients, and the second speed coefficient is D*E.

[0076] S730: When the connection state requirement of the clutch 201 is the engaged state and the total flow demand of the first oil pump 101 is greater than the upper limit flow of the first oil pump 101, the target speed of the first oil pump motor 102 is the product of the upper limit flow of the first oil pump 101 and the first speed coefficient.

[0077] Specifically, the target speed N_PmpLo of the first oil pump motor 102 is equal to C*Flow_Lo_Lim, where Flow_Lo_Lim is the upper limit flow rate of the first oil pump 101 and C is the first speed coefficient.

[0078] And, the target speed of the second oil pump motor is determined according to the following method: S731 : Determine a flow rate regulation deviation according to the total flow rate demand of the first oil pump 101 and the upper flow rate limit of the first oil pump 101 .

[0079] Specifically, the flow regulation deviation is the flow rate that is still short of the total flow rate after pumping cooling oil according to the upper limit flow rate of the first oil pump 101. This flow rate is the flow rate requirement for the second oil pump 103 to provide cooling oil for the cooling oil circuit 300; the flow regulation deviation Flow_Hi_C=Flow_Lo-Flow_Lo_Lim, Flow_Lo is the total flow rate requirement of the first oil pump 101, and Flow_Lo_Lim is the upper limit flow rate of the first oil pump 101.

[0080] S732 : Determine a first speed of the second oil pump motor 104 based on the flow regulation deviation. The first speed is the speed of the second oil pump motor 104 corresponding to the flow requirement of the second oil pump 103 providing cooling oil to the cooling oil circuit 300 .

[0081] Specifically, the first speed N_PmpHi of the second oil pump motor 104 is equal to F*Flow_Hi_C, where F is a coefficient and Flow_Hi_C is a flow regulation deviation.

[0082] S733 : The maximum value of the first rotation speed of the second oil pump motor 104 and the rotation speed required when the clutch 201 is engaged is used as the target rotation speed of the second oil pump motor 104 .

[0083] Since the second oil pump 103 is required to provide sufficient hydraulic pressure to press the clutch 201 when the clutch 201 is in the engaged state, the target speed of the second oil pump motor 104 needs to meet both the speed corresponding to the flow demand of the second oil pump 103 to provide cooling oil to the cooling oil circuit 300 and the speed corresponding to pressing the clutch 201, that is, the maximum value of the first speed of the second oil pump motor 104 and the speed required when the clutch 201 is pressed is used as the target speed of the second oil pump motor 104.

[0084] Specifically, the target speed N_PmpC of the second oil pump motor 104 is MAX(N_PmpHi, N_PmpHi_Close), where N_PmpHi is the first speed of the second oil pump motor 104 and N_PmpHi_Close is the speed required when the clutch 201 is tightened.

[0085] In this optional embodiment, based on the total flow requirement of the first oil pump 101, the connection status requirement of the clutch 201 and the torque requirement of the clutch 201, the target speed of the first oil pump motor 102 and the target speed of the second oil pump motor 104 are accurately calculated, so that the first oil pump 101 and the second oil pump 103 can provide accurate hydraulic oil flow according to different vehicle operating conditions.

[0086] An embodiment of the present invention provides a vehicle including a hybrid transmission hydraulic system, wherein the hybrid transmission hydraulic system is the hybrid transmission hydraulic system described in the above embodiment.

[0087] In other words, a vehicle includes a hybrid transmission hydraulic system, wherein the hybrid transmission hydraulic system includes: a first oil pump and a first oil pump motor, wherein the first oil pump motor is used to drive the first oil pump, and the first oil pump is used to provide cooling oil to a cooling oil circuit in the hybrid transmission; a second oil pump and a second oil pump motor, the second oil pump motor being used to drive the second oil pump, the second oil pump being used at least to control engagement or disengagement of a clutch in the hybrid transmission; an on-off valve, wherein the oil inlet of the on-off valve is connected to the second oil pump, and the oil outlet of the on-off valve is used to be connected to the clutch and / or the cooling oil circuit, and the on-off valve is used to control the communication between the second oil pump and the clutch and / or the cooling oil circuit by switching its switch position; A controller configured to: Obtaining a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch; wherein the connection state requirement of the clutch is a connection state that the clutch currently needs to switch to; Controlling the switching of the switch position of the switch valve according to the total flow requirement of the first oil pump and the connection state requirement of the clutch; and A target speed of the first oil pump motor and a target speed of the second oil pump motor are determined according to a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch.

[0088] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented by instructing the relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When executed, the program can include the processes in the above-described method embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM). In this application, the units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in a single location or distributed across multiple network elements. Some or all of these units can be selected based on actual needs to achieve the objectives of the embodiments of the present invention. Furthermore, the functional units in the various embodiments of the present invention can be integrated into a single processing unit, each unit can exist physically separately, or two or more units can be integrated into a single unit. These integrated units can be implemented in either hardware or software functional units.

[0089] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A hybrid transmission hydraulic system, characterized in that: include: a first oil pump and a first oil pump motor, wherein the first oil pump motor is used to drive the first oil pump, and the first oil pump is used to provide cooling oil to a cooling oil circuit in the hybrid transmission; a second oil pump and a second oil pump motor, the second oil pump motor being used to drive the second oil pump, the second oil pump being used at least to control engagement or disengagement of a clutch in the hybrid transmission; an on-off valve, wherein an oil inlet of the on-off valve is connected to the second oil pump, and an oil outlet of the on-off valve is used to be connected to the clutch or to be connected to the clutch and the cooling oil circuit, and the on-off valve is used to control the communication between the second oil pump and the clutch or between the clutch and the cooling oil circuit by switching its switch position; A controller configured to: Obtaining a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch; wherein the connection state requirement of the clutch is a connection state that the clutch currently needs to switch to; Controlling the switching of the switch position of the switch valve according to the total flow requirement of the first oil pump and the connection state requirement of the clutch; and A target speed of the first oil pump motor and a target speed of the second oil pump motor are determined according to a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch.

2. The hybrid transmission hydraulic system according to claim 1, characterized in that: The cooling oil circuit includes cooling oil circuits for the drive motor, the generator, and the clutch. Obtaining the total flow requirement of the first oil pump includes: Acquiring the temperature of the drive motor, the temperature of the generator, and the temperature of the clutch; determining a flow rate requirement of the drive motor according to a temperature of the drive motor; determining a flow requirement of the generator according to a temperature of the generator; determining a flow requirement of the clutch according to a temperature of the clutch; The total flow requirement of the first oil pump is determined according to the flow requirement of the drive motor, the flow requirement of the generator, and the flow requirement of the clutch.

3. The hybrid transmission hydraulic system according to claim 2, characterized in that: Determining the total flow requirement of the first oil pump according to the flow requirement of the drive motor, the flow requirement of the generator, and the flow requirement of the clutch includes: determining a first flow requirement of the first oil pump according to a flow requirement of the drive motor; determining a second flow requirement of the first oil pump according to the flow requirement of the generator; determining a third flow requirement of the first oil pump according to the flow requirement of the clutch; A total flow requirement of the first oil pump is determined according to the first flow requirement, the second flow requirement, and the third flow requirement.

4. The hybrid transmission hydraulic system according to claim 3, characterized in that: Determining the total flow requirement of the first oil pump according to the first flow requirement, the second flow requirement, and the third flow requirement includes: The largest flow demand among the first flow demand, the second flow demand, and the third flow demand is used as the total flow demand of the first oil pump.

5. The hybrid transmission hydraulic system according to claim 1, characterized in that: The switch valve has a first switch position and a second switch position. When the switch valve is in the first switch position, the second oil pump is connected to the clutch. When the switch valve is in the second switch position, the second oil pump is simultaneously connected to the clutch and the cooling oil circuit.

6. The hybrid transmission hydraulic system according to claim 5, characterized in that: The controlling the switching of the switch position of the switch valve according to the total flow requirement of the first oil pump and the connection state requirement of the clutch includes: When the connection state requirement of the clutch is switching from a disengaged state to an engaged state, or when the connection state requirement of the clutch is an engaged state and the total flow demand of the first oil pump is less than or equal to the upper limit flow of the first oil pump, controlling the switching valve to be in a first switching position to connect the second oil pump to the clutch; When the connection state requirement of the clutch is the engaged state and the total flow demand of the first oil pump is greater than the upper limit flow of the first oil pump, the switching valve is controlled to be in the second switching position so that the second oil pump is connected to both the clutch and the cooling oil circuit.

7. The hybrid transmission hydraulic system according to claim 6, characterized in that: Determining the target speed of the first oil pump motor and the target speed of the second oil pump motor according to the total flow requirement of the first oil pump, the connection state requirement of the clutch, and the torque requirement of the clutch includes: When the clutch connection state requirement is a disengaged state, the target speed of the first oil pump motor is the product of the total flow requirement of the first oil pump and the first speed coefficient, and the target speed of the second oil pump motor is 0; When the connection state requirement of the clutch is switching from a disengaged state to an engaged state, or when the connection state requirement of the clutch is an engaged state and the total flow demand of the first oil pump is less than or equal to the upper limit flow rate of the first oil pump, the target speed of the first oil pump motor is the product of the total flow demand of the first oil pump and a first speed coefficient, and the target speed of the second oil pump motor is the product of the torque requirement of the clutch and the second speed coefficient; When the clutch connection state requirement is an engaged state and the total flow demand of the first oil pump is greater than the upper limit flow of the first oil pump, the target speed of the first oil pump motor is the product of the upper limit flow of the first oil pump and the first speed coefficient, and the target speed of the second oil pump motor is determined according to the following method: determining a flow regulation deviation according to a total flow demand of the first oil pump and an upper flow limit of the first oil pump; determining a first speed of the second oil pump motor according to the flow regulation deviation; The maximum value of the first rotation speed of the second oil pump motor and the rotation speed required when the clutch is engaged is used as the target rotation speed of the second oil pump motor.

8. The hybrid transmission hydraulic system according to any one of claims 1 to 7, characterized in that: The switch valve is a solenoid valve.

9. A control method for a hybrid transmission hydraulic system, characterized in that: The hydraulic system includes a first oil pump, a first oil pump motor, a second oil pump, a second oil pump motor, and a switch valve. The oil inlet of the switch valve is connected to the second oil pump, and the oil outlet of the switch valve is used to be connected to the clutch and / or the cooling oil circuit. The switch valve is used to control the second oil pump to be connected to the clutch and / or the cooling oil circuit. The control method includes: obtaining a total flow requirement of the first oil pump, obtaining a connection state requirement of the clutch, and obtaining a torque requirement of the clutch; controlling the switch position of the switch valve according to the total flow requirement of the first oil pump and the connection state requirement of the clutch; and A target speed of the first oil pump motor and a target speed of the second oil pump motor are determined according to a total flow requirement of the first oil pump, a connection state requirement of the clutch, and a torque requirement of the clutch.

10. A vehicle, characterized in that: The vehicle includes a hybrid transmission hydraulic system, and the hybrid transmission hydraulic system is the hybrid transmission hydraulic system according to any one of claims 1 to 8.

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