Power coordination control method and device of dual-motor-hydraulic coaxial series range extending system and vehicle

Abstract

The invention provides a power coordination control method and device for a dual-motor-hydraulic coaxial series range extending system and a vehicle, and relates to the technical field of vehicle range extending systems.The method comprises the steps that current operation information of the dual-motor-hydraulic coaxial series range extending system is collected, and first required power of the dual-motor-hydraulic coaxial series range extending system is determined; determining a set rotating speed of the speed regulation unit according to the first required power; power distribution is conducted according to the current operation information and the first required power, the set torque of a torque adjusting unit is obtained, and the torque adjusting unit comprises at least one of a first range extending motor, a second range extending motor and an engine; the control signal is generated according to the set rotating speed and the set torque of each torque adjusting unit so as to control the first range extending motor, the second range extending motor and the engine to operate, the power generation requirement is met while the working efficiency is guaranteed, and the rotating speed stability and the disturbance rejection capacity of the rotating shaft can be improved under the condition that hydraulic power calculation is not accurate. And coupler risks are reduced.

Description

Technical Field

[0001] This application relates to the field of vehicle range extender system technology, specifically to a power coordination control method, device, and vehicle for a dual-motor-hydraulic coaxial series range extender system. Background Technology

[0002] The dual-motor-hydraulic coaxial series range extender system suffers from a strong coupling problem between power generation and hydraulic power take-off. While ensuring power generation, it is necessary to meet the power take-off requirements of the hydraulic superstructure. Economical power generation and operational needs become the main contradiction. Changes in operating conditions and battery state of charge (SOC) pose greater challenges to the performance and control strategy of the range extender. Due to the response lag and overflow loss of hydraulic valves, the actual power calculation of the hydraulic system has a large error, which further affects the power regulation of the range extender and leads to unstable speed. Summary of the Invention

[0003] In view of this, this application provides a power coordination control method, device and vehicle for a dual-motor-hydraulic coaxial series range extender system, which prioritizes loading operation efficiency while taking into account power generation needs. In the case of inaccurate hydraulic power calculation, it can improve the rotational speed stability and anti-disturbance capability of the rotating shaft and reduce coupling risks.

[0004] To achieve the above objectives, this application provides the following technical solution: a power coordination control method for a dual-motor-hydraulic coaxial series range extender system, wherein the dual-motor-hydraulic coaxial series range extender system includes: a first range extender motor, a second range extender motor, and an engine, wherein the engine is coaxially connected to the first range extender motor and the second range extender motor via a coupling, and the first range extender motor and the second range extender motor are coaxially connected in series with a hydraulic system; the method includes: acquiring current operating information of the dual-motor-hydraulic coaxial series range extender system and determining a first required power of the dual-motor-hydraulic coaxial series range extender system; determining a set speed of a speed regulating unit based on the first required power, wherein the speed regulating unit is either the first range extender motor or the engine; performing power allocation based on the current operating information and the first required power to obtain a set torque of a torque regulating unit, wherein the torque regulating unit includes at least one of the first range extender motor, the second range extender motor, and the engine; generating control signals based on the set speed and the set torque of each of the torque regulating units to control the operation of the first range extender motor, the second range extender motor, and the engine.

[0005] In one embodiment of this application, if the dual-motor-hydraulic coaxial series range extender system operates in a first control mode, the first control mode being engine torque control, first range extender motor speed and torque control, and second range extender motor torque control; the step of allocating power according to the current operating information and the first required power to obtain the set torque of the torque adjustment unit includes: determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system according to the first required power, the power generation mode including an economical power generation mode and a standard power generation mode, the economical power generation mode being power generation by the first range extender motor, and the standard power generation mode being power generation by the first range extender motor and the second range extender motor; if the dual-motor-hydraulic coaxial series range extender system adopts the economical power generation mode, then the set torque of the first range extender motor and the engine is allocated according to the current operating information and the first required power; if the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation mode, then the set torque of the first range extender motor, the second range extender motor, and the engine is allocated according to the current operating information and the first required power.

[0006] In one embodiment of this application, the step of allocating the set torque of the first range extender motor and the engine according to the current operating information and the first required power includes: determining the upper limit of the torque of the first range extender motor based on the maximum discharge capacity of the battery and the actual torque of the first range extender motor; determining the initial set torque of the engine according to the total required power of the range extender load, wherein the range extender load includes the first range extender motor, the second range extender motor and the hydraulic system, and the total required power of the range extender load is the sum of the first required power and the second required power of the hydraulic system; calculating the limiting torque when the battery is overcharged, and determining the set torque of the engine to be the smaller value between the limiting torque and the initial set torque.

[0007] In one embodiment of this application, the step of allocating the set torque of the first range extender motor, the second range extender motor, and the engine according to the current operating information and the first required power includes: determining whether the second range extender motor outputs negative torque; if not, returning to the step of determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system according to the first required power; if the second range extender motor outputs negative torque, determining that the upper limit of the torque of the first range extender motor is zero; calculating the set torque of the second range extender motor according to the difference between the set speed and the actual speed of the first range extender motor and the first required power; determining the initial set torque of the engine according to the sum of the first required power and the second required power of the hydraulic system and the difference between the set speed and the actual speed of the first range extender motor; calculating the limiting torque when the battery is overcharged, and determining that the set torque of the engine is the smaller value between the limiting torque and the initial set torque.

[0008] In one embodiment of this application, if the dual-motor-hydraulic coaxial series range extender system operates in a second control mode, the second control mode being engine speed control and torque control of the first and second range extenders; the step of allocating power according to the current operating information and the first required power to obtain the set torque of the torque adjustment unit includes: obtaining the total set torque of the first and second range extenders according to the current operating information and the first required power; determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system according to the first required power, the power generation mode including an economical power generation mode and a standard power generation mode, the economical power generation mode being power generation by the first range extender, and the standard power generation mode being power generation by the first and second range extenders; if the dual-motor-hydraulic coaxial series range extender system adopts the economical power generation mode, then the set torque of the first range extender is determined as the total set torque; if the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation mode, then the total set torque is allocated to the first and second range extenders at a preset ratio.

[0009] In one embodiment of this application, obtaining the total set torque of the first range extender motor and the second range extender motor based on the current operating information and the first required power includes: calculating a first total set torque of the first range extender motor and the second range extender motor based on the first required power and the set speed; correcting the first total set torque based on the difference between the set speed and the actual speed of the engine during the load-bearing process to obtain a second total set torque of the first range extender motor and the second range extender motor; and correcting the second total set torque based on the total current of the hydraulic pump displacement during the lifting operation to obtain the final total set torque of the first range extender motor and the second range extender motor.

[0010] In one embodiment of this application, determining the set speed of the speed control unit based on the first required power includes: determining the control mode of the dual-motor-hydraulic coaxial series range extender system; if the dual-motor-hydraulic coaxial series range extender system operates in a first control mode, then determining the target speed of the first range extender motor based on the first required power, and determining the set speed of the first range extender motor in combination with the required speed of the hydraulic system, wherein the first control mode is engine torque control, first range extender motor speed-torque control, and second range extender motor torque control; if the dual-motor-hydraulic coaxial series range extender system operates in a second control mode, then determining the target speed of the engine based on the first required power, and determining the set speed of the engine in combination with the required speed of the hydraulic system, wherein the second control mode is engine speed control, first range extender motor, and second range extender motor torque control.

[0011] As a second aspect of this application, this application also provides a power coordination control device for a dual-motor-hydraulic coaxial series range extender system. The dual-motor-hydraulic coaxial series range extender system includes: a first range extender motor, a second range extender motor, and an engine. The engine is coaxially connected to the first range extender motor and the second range extender motor via a coupling. The first range extender motor and the second range extender motor are coaxially connected in series with a hydraulic system. The device includes: an information acquisition module for acquiring the current operating information of the dual-motor-hydraulic coaxial series range extender system and determining the first required power of the dual-motor-hydraulic coaxial series range extender system; a speed control module for determining the set speed of a speed regulating unit based on the first required power, wherein the speed regulating unit is the first range extender motor or the engine; a torque control module for distributing power according to the current operating information and the first required power, and obtaining the set torque of a torque regulating unit, wherein the torque regulating unit includes at least one of the first range extender motor, the second range extender motor, and the engine; and an output control module for generating control signals based on the set speed and the set torque of each of the torque regulating units to control the operation of the first range extender motor, the second range extender motor, and the engine.

[0012] As a third aspect of this application, embodiments of this application also provide a vehicle, including: a memory for storing an executable computer program; and a processor for calling and running the executable computer program from the memory, causing the processor to perform the aforementioned method.

[0013] As a fourth aspect of this application, embodiments of this application also provide a computer-readable storage medium storing a computer program that, when executed, implements the aforementioned method.

[0014] This application provides a power coordination control method for a dual-motor-hydraulic coaxial series range extender system. This method collects the current operating information of the dual-motor-hydraulic coaxial series range extender system and determines the first required power. Based on the first required power, it determines the set speed of a speed regulating unit, which is either the first range extender motor or the engine. Power is allocated based on the current operating information and the first required power to obtain the set torque of a torque regulating unit, which includes at least one of the first range extender motor, the second range extender motor, and the engine. Control signals are generated based on the set speed and the set torque of each torque regulating unit to control the operation of the first range extender motor, the second range extender motor, and the engine. This method prioritizes loading efficiency while also considering power generation needs. In cases where hydraulic power calculations are inaccurate, it improves the speed stability and anti-disturbance capability of the rotating shaft and reduces coupling risks. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0016] Figure 1 This is a schematic diagram illustrating the power coordination control of a dual-motor-hydraulic coaxial series range extender system provided in an embodiment of this application.

[0017] Figure 2 This is a schematic diagram of the dual-motor-hydraulic coaxial series range extender system provided in an embodiment of this application.

[0018] Figure 3 This is an example diagram illustrating the power coordination control method for a dual-motor-hydraulic coaxial series range extender system provided in an embodiment of this application.

[0019] Figure 4 The diagram shown is a structural schematic of a power coordination control device for a dual-motor-hydraulic coaxial series range extender system provided in an embodiment of this application.

[0020] Figure 5 The diagram shown is a structural schematic of a vehicle provided in an embodiment of this application. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] In related technologies, the dual-motor-hydraulic coaxial series range extender system suffers from a strong coupling problem between power generation and hydraulic power take-off. Ensuring power generation while simultaneously meeting the power take-off requirements of the hydraulic superstructure presents a major challenge: balancing economical power generation with operational needs. Changes in operating conditions and battery state of charge (SOC) pose significant challenges to the range extender's performance and control strategies. Furthermore, due to response lag and overflow losses in the hydraulic system, the actual power calculation of the hydraulic system has substantial errors, further impacting the range extender's power regulation. The most direct manifestation is unstable engine speed. For components, the engine's slow torque response causes the speed-controlled motor to actively consume power to maintain speed. If the two motors have opposite torque directions, the risk of coupling fatigue fracture is also high.

[0023] To address the issues in related technologies where loading efficiency and power generation requirements cannot be simultaneously considered, and where hydraulic power calculations are inaccurate, this application provides a power coordination control method for a dual-motor-hydraulic coaxial series range extender system. Figure 1 The diagram shown is a flowchart illustrating a power coordination control method for a dual-motor-hydraulic coaxial series range extender system provided in an embodiment of this application. The dual-motor-hydraulic coaxial series range extender system includes: a first range extender motor, a second range extender motor, and an engine. The engine is coaxially connected to the first and second range extender motors via a coupling. The first and second range extender motors are coaxially connected in series with the hydraulic system. Figure 1 As shown, the power coordination control method of this dual-motor-hydraulic coaxial series range extender system includes: Step S11: Collect the current operating information of the dual-motor-hydraulic coaxial series range extender system and determine the first required power of the dual-motor-hydraulic coaxial series range extender system.

[0024] The structure of the dual-motor-hydraulic coaxial series range extender system is shown in the figure. Figure 2The engine is a diesel engine. The engine is coaxially connected to the first range extender motor ISG1 and the second range extender motor ISG2 via a coupling. The engine generates positive torque, while the first and second range extender motors ISG1 and ISG2 generate negative torque to generate electricity. The rotating shaft simultaneously outputs the torque to the transfer case in the hydraulic system. The transfer case is connected to the working pump 1, working pump 2, steering pump, fan, and circulation pump via a power take-off (PTO). Essentially, the transfer case is a single-shaft input, multi-shaft output reducer, primarily providing power input to the working pump, steering pump, fan, and circulation pump of the hydraulic system. Simultaneously, the hydraulic pump system connected to the transfer case is considered a load of the engine, and each hydraulic pump provides hydraulic power to the oil circuits of the multi-way directional valves. The first motor control unit MCU1 is connected to the Controller Area Network (CAN) bus and is used to control the first range extender motor ISG1. The second motor control unit MCU2 is connected to the CAN bus and is used to control the second range extender motor ISG2. The hydraulic control unit HCU is connected to the CAN bus and is used to control the hydraulic system. The first range extender motor ISG1, the second range extender motor ISG2, and the drive motor MT are connected to the electrical control cabinet. The power battery pack is connected to the electrical control cabinet via a high-voltage DC harness. The range extender control unit RCU is connected to the CAN bus. The power coordination control method of the dual-motor-hydraulic coaxial series range extender system in this application embodiment is applied to the range extender control unit RCU.

[0025] The power battery pack electrodes and the dual range extender motors, after AC / DC conversion, generate DC power, which is then coupled to the DC / AC power of the drive motor MT. This DC power is then fed into the DC bus system. The battery can be charged and discharged, the drive motor MT can be driven and provide energy feedback, and the first range extender motor ISG1 and the second range extender motor ISG2 can consume and generate electricity. The engine control unit ECU, the first motor control unit MCU1, the second motor control unit MCU2, the third motor control unit MCU3, and the range extender control unit RCU are connected via a Controller Area Network (CAN) bus.

[0026] In step S11, the current operating information of the dual-motor-hydraulic coaxial series range extender system is collected based on the CAN bus (CANH and CANL). This current operating information mainly includes the remaining battery charge (SOC), key charge, actual engine speed and torque, actual speed and torque of the first range extender motor ISG1 and the second range extender motor ISG2, battery power limits from the Battery Management System (BMS), hydraulic pump pressure signal, total hydraulic pump displacement current, total hydraulic system power requirement, and minimum hydraulic system speed requirement. To improve the responsiveness of the RCU power control, the communication rate of the messages transmitting the current operating information should be at least 10ms and should not exceed 50ms.

[0027] Based on the battery SOC (State of Charge) of the range extender, multiple fixed-point power outputs are determined. Due to the rapidly changing operating conditions of loaders, a wide speed range is required to adapt to these varied conditions, while also considering the economic efficiency of power generation, aiming to position the power output within the engine's economic range. The engine's economic range typically refers to the engine speed between 2000 and 3500 rpm, where fuel efficiency is highest. This economic range may vary slightly depending on the vehicle model and operating conditions. The initial power requirement of the dual-motor-hydraulic coaxial series range extender system can be determined based on the remaining battery charge. A table mapping the remaining battery charge to the initial power requirement is stored, and the corresponding initial power requirement is obtained by looking up this table based on the remaining battery charge.

[0028] Step S12: Determine the set speed of the speed control unit based on the first required power, wherein the speed control unit is the first range extender motor or the engine.

[0029] The range extender control unit (RCU) can be set to two control modes. The first control mode (Mode 1) controls engine torque, the speed and torque of the first range extender motor ISG1 (Motor 1), and the torque of the second range extender motor ISG2 (Motor 2). In this mode, the engine drives all external loads (without load adaptation), and Motor 1 handles the transition of its power generation point and load adaptation. Motor 2 only performs power generation. The second control mode (Mode 2) controls engine speed, and the first and second range extender motors ISG1 and ISG2 perform torque control. In this mode, the engine drives all external loads (with load adaptation, exceeding the motor's load-carrying capacity), and the engine handles the transition of its power generation point and load adaptation. Both motors ISG1 and ISG2 only perform power generation. The battery is a passive component in energy management. By rationally designing the power generation of the range extender motors, the vehicle's energy mode can be switched, for example: joint drive by the battery and range extender motors, battery-only drive, or range extender motor-only drive.

[0030] When the dual-motor-hydraulic coaxial series range extender system operates in the first control mode, the speed control unit is the first range extender motor. When the dual-motor-hydraulic coaxial series range extender system operates in the first control mode, the speed control unit is the engine. In this embodiment, a correspondence table between the first required power and the set speed of the speed control unit can be preset. After determining the first required power of the dual-motor-hydraulic coaxial series range extender system, the corresponding set speed of the first range extender motor or engine (as the speed control unit) can be obtained by looking up the correspondence table.

[0031] Step S13: Based on the current operating information and the first required power, power allocation is performed to obtain the set torque of the torque adjustment unit. The torque adjustment unit includes at least one of the first range extender motor, the second range extender motor, and the engine.

[0032] In this embodiment, if the dual-motor-hydraulic coaxial series range extender system operates in the first control mode, the first required power is allocated to the first range extender motor, the second range extender motor, and the engine based on the current operating information, and the set torques of the first range extender motor, the second range extender motor, and the engine are obtained. During the power allocation process, to address the issue of inaccurate hydraulic power estimation, a speed-controlled and torque-controlled motor is used for power compensation to stabilize the speed. Furthermore, the torque direction between the two motors is coordinated during range extender power load and economic / standard power generation to prevent abnormal fluctuations in the coupling speed. Simultaneously, to avoid battery overcharging and over-discharging issues caused by motor 1 speed adjustment, an upper limit for motor 1 torque is set based on the power generation mode, and the engine torque is limited based on the battery charging and discharging power. Conversely, a lower limit for motor 1 torque is set to achieve controllable speed regulation.

[0033] If the dual-motor-hydraulic coaxial series range extender system operates in the second control mode, the first required power is allocated to the first and second range extender motors based on the current operating information. During the power allocation process, based on the identification of the work being performed, the power generation is reduced during lifting to ensure operational efficiency. This prioritizes loading efficiency while also considering power generation needs. In cases where hydraulic power calculations are inaccurate, it improves the rotational speed stability and anti-disturbance capability of the rotating shaft, reducing coupling risks.

[0034] Step S14: Generate control signals based on the set speed and the set torque of each of the torque adjustment units to control the operation of the first range extender motor, the second range extender motor, and the engine.

[0035] The set torque and set speed of the first range extender motor, the second range extender motor, and the engine are determined. The control signals of the first range extender motor, the second range extender motor, and the engine are determined and transmitted to the first range extender motor, the second range extender motor, and the engine to control the first range extender motor, the second range extender motor, and the engine to operate based on the corresponding set speed and set torque.

[0036] The power coordination control method of the dual-motor-hydraulic coaxial series range extender system in this application embodiment collects the current operating information of the dual-motor-hydraulic coaxial series range extender system and determines the first required power of the dual-motor-hydraulic coaxial series range extender system; determines the set speed of the speed regulating unit based on the first required power, wherein the speed regulating unit is the first range extender motor or the engine; performs power allocation based on the current operating information and the first required power to obtain the set torque of the torque regulating unit, wherein the torque regulating unit includes at least one of the first range extender motor, the second range extender motor, and the engine; and generates control signals based on the set speed and the set torque of each of the torque regulating units to control the operation of the first range extender motor, the second range extender motor, and the engine. This method prioritizes loading operation efficiency while also considering power generation needs. In cases where hydraulic power calculation is inaccurate, it can improve the speed stability and anti-disturbance capability of the rotating shaft and reduce coupling risks.

[0037] To more clearly illustrate the technical solutions provided in the embodiments of this application, the following further explains a power coordination control method for a dual-motor-hydraulic coaxial series range extender system provided in this application.

[0038] Considering that the dual-motor-hydraulic coaxial series range extender system operates in different control modes, different adjustment units are used. Therefore, in this embodiment, optionally, determining the set speed of the speed regulating unit based on the first required power includes: determining the control mode of the dual-motor-hydraulic coaxial series range extender system; if the dual-motor-hydraulic coaxial series range extender system operates in a first control mode, then determining the target speed of the first range extender motor based on the first required power, and determining the set speed of the first range extender motor in conjunction with the required speed of the hydraulic system, wherein the first control mode is engine torque control, first range extender motor speed-torque control, and second range extender motor torque control; if the dual-motor-hydraulic coaxial series range extender system operates in a second control mode, then determining the target speed of the engine based on the first required power, and determining the set speed of the engine in conjunction with the required speed of the hydraulic system, wherein the second control mode is engine speed control, first range extender motor torque control, and second range extender motor torque control.

[0039] In this embodiment, the control mode of the dual-motor-hydraulic coaxial series range extender system is first determined. Before activation, the control mode of the dual-motor-hydraulic coaxial series range extender system is pre-calibrated. Specifically, the control mode can be calibrated according to the vehicle model and customer requirements. Generally, once the control mode of the vehicle's dual-motor-hydraulic coaxial series range extender system is calibrated, it is consistently used. If the dual-motor-hydraulic coaxial series range extender system operates in the first control mode, the first range extender motor is used as the speed control unit. The first control mode includes engine torque control, first range extender motor speed-torque control, and second range extender motor torque control. The target speed of the first range extender motor can be determined based on the first required power. Specifically, based on the fixed-point power requirement, i.e., the first required power, the original target speed of the first range extender motor is obtained by looking up a table. n 1. Then, combine the required rotational speed of the hydraulic system. n h Determine the set speed of the first range extender motor, that is, finally determine the set speed of the first range extender motor. n 1_set =max( n 1, n h (Among them, the original target speed set by the first range extender motor is taken.) n 1. Speed ​​required by the hydraulic system n h The larger value in the range can meet the speed requirements of the power generation and hydraulic systems.

[0040] If the dual-motor-hydraulic coaxial series range extender system operates in the second control mode, using the engine as the speed control unit, the second control mode involves engine speed control and torque control of the first and second range extender motors. The target engine speed can be determined based on the first required power, specifically based on the fixed-point power requirement, i.e., the first required power, by looking up a table to obtain the engine's originally set target speed. n e Then, combined with the required rotational speed of the hydraulic system. n h Determine the engine's set speed, that is, finally determine the engine's set speed. n e_set =max( n e , n h (Among them, the original target speed set by the engine is taken.) n e Speed ​​required by the hydraulic system n hThe larger value in the range can meet the speed requirements of the power generation and hydraulic systems.

[0041] This embodiment of the application determines the set speed of the speed regulating unit by combining the target speed of the speed regulating unit determined by the first required power with the required speed of the hydraulic system. This can simultaneously meet the speed requirements of the power generation and hydraulic system, ensuring loading operation efficiency while also taking into account the power generation requirements.

[0042] The torque adjustment unit involved in power distribution in the dual-motor-hydraulic coaxial series range extender system varies depending on the control mode. In the first control mode, the first range extender motor, the second range extender motor, and the engine can all participate in power distribution. In the second control mode, the engine does not participate in power distribution; power distribution is primarily handled by the first and second range extender motors.

[0043] If the dual-motor-hydraulic coaxial series range extender system is operating in the first control mode, the power distribution of the first range extender motor, the second range extender motor, and the engine needs to take into account the first power requirement of the dual-motor-hydraulic coaxial series range extender system. At the same time, it is also necessary to consider the small probability of battery overcharging and over-discharging, operating efficiency, coupling risks, and inaccurate hydraulic power estimation that may occur during the control process. Based on this, optionally, if the dual-motor-hydraulic coaxial series range extender system operates in a first control mode, the first control mode being engine torque control, first range extender motor speed-torque control, and second range extender motor torque control; the step of allocating power according to the current operating information and the first required power to obtain the set torque of the torque adjustment unit includes: determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system according to the first required power, the power generation mode including an economical power generation mode and a standard power generation mode, the economical power generation mode being power generation by the first range extender motor, and the standard power generation mode being power generation by the first range extender motor and the second range extender motor; if the dual-motor-hydraulic coaxial series range extender system adopts the economical power generation mode, then the set torque of the first range extender motor and the engine is allocated according to the current operating information and the first required power; if the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation mode, then the set torque of the first range extender motor, the second range extender motor, and the engine is allocated according to the current operating information and the first required power.

[0044] To maximize the utilization of the motor's efficient operating range and improve energy conversion efficiency, the allocation of the first required power can be achieved through two power generation methods: standard power generation and economic power generation. Economic power generation involves only the first range extender motor operating, while standard power generation involves both the first and second range extenders operating. If the required first power is low and a single motor can meet the demand, economic power generation can be used. If the required first power is high and a single motor cannot meet the demand, standard power generation is required. In this embodiment, the first required power can be compared with a power threshold. The power threshold can be set as needed and is not specifically limited here. If the first required power is less than the power threshold, economic power generation is used. If the first required power is greater than or equal to the power threshold, standard power generation is used. If the dual-motor-hydraulic coaxial series range extender system uses economic power generation, the first range extender motor is primarily used for power generation. The engine's output torque is mainly used to limit low-probability issues such as battery overcharging and over-discharging, coupling risks, and inaccurate hydraulic power estimation during control. Thus, the set torques of the first range extender motor and the engine can be allocated based on the current operating information and the first required power. If the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation method, both the first and second range extender motors can be used for power generation, and the problems of operating efficiency and coupling risks that occur during the control process can be solved. In this way, the set torque of the first range extender motor, the second range extender motor and the engine can be allocated according to the current operating information and the first required power.

[0045] This application embodiment allocates the first required power by using different power generation methods based on different power demands. By making the most of the motor's efficient operating range, the energy conversion rate is improved. At the same time, in the case of inaccurate hydraulic power calculation, the rotational speed stability and anti-disturbance capability of the rotating shaft can be improved, and the coupling risk can be reduced.

[0046] When the first range extender motor acts as the speed control unit, and the dual-motor-hydraulic coaxial series range extender system adopts an economical power generation method, the first range extender motor uses speed-torque control. This requires the first range extender motor to support single-phase torque limitation, and improper torque limitation settings during power generation can easily lead to engine overshoot. Furthermore, analysis of hydraulic power inaccuracies reveals that if the actual hydraulic power is too low, it indicates that the engine's set torque is too high. Therefore, the first range extender motor's speed-torque control adapts to the load and increases the negative torque of power generation. To reduce the risk of battery overcharging, the engine torque is limited, thus limiting the lower limit of the first range extender motor's torque. With the engine torque limited and reduced, the first range extender motor's load adaptation naturally reduces the power generation torque, thereby suppressing the tendency for battery overcharging. For system stability, real-time adjustments are not performed; only the battery's maximum charging capacity is considered. Based on this, in this embodiment of the application, optionally, the step of allocating the set torque of the first range extender motor and the engine according to the current operating information and the first required power includes: determining the upper limit of the torque of the first range extender motor based on the maximum discharge capacity of the battery and the actual torque of the first range extender motor; determining the initial set torque of the engine according to the total required power of the range extender load, wherein the range extender load includes the first range extender motor, the second range extender motor and the hydraulic system, and the total required power of the range extender load is the sum of the first required power and the second required power of the hydraulic system; calculating the limiting torque when the battery is overcharged, and determining the set torque of the engine to be the smaller value between the limiting torque and the initial set torque.

[0047] If the actual hydraulic power is too low, it indicates that the engine's set torque is too high. In this case, the first range extender motor will adaptively reduce the negative torque generated, and may even generate positive torque during load loading. Reducing the negative torque generated by the first range extender motor has no impact on battery overcharging. However, if the first range extender motor generates positive torque during load loading or adjustment, there is a risk of battery over-discharge. Therefore, the upper limit of the first range extender motor's torque can be based on the battery's maximum discharge capacity, taking into account power consumption. Thus, the upper limit of the first range extender motor's torque can be determined based on the battery's maximum discharge capacity and the actual torque of the first range extender motor. The upper limit of the first range extender motor's torque is: T 1_set_max =9550 ( P Bmax - P mt_act ) / n 1_set ,in, T 1_set_max This is the upper limit of the torque of the first range extender motor. P Bmax The maximum battery power can be a battery power limit calculated based on the current limit.P mt_act This represents the actual power of the first range extender motor. The second range extender motor does not allocate power; therefore, the torque of the second range extender motor used for power generation is... T 2_set =0.

[0048] After determining the upper limit of the torque of the first range extender motor, in order to address issues such as low-probability battery overcharging and over-discharging, coupling risks, and inaccurate hydraulic power estimation during the control process, the range extender load can be used as the research object, the engine as the power source, and the hydraulic pump system connected to the first and second range extender motors and the transfer case as the load. The power output of the engine is balanced with the power demand of the dual motors and the hydraulic system. Therefore, the initial set torque of the engine can be determined based on the total power demand of the range extender load. T e_set1 =9550 ( P h + P RE ) / n 1_set ,in, T e_set1 The initial set torque for the engine. P h For the power required by the hydraulic system, P RE The first required power is [specified]. To limit the lower limit of the torque of the first range extender motor and reduce the risk of battery overcharging, the engine's set torque can be reversed. Specifically, the limit torque when the battery is overcharged can be calculated, and the engine's set torque can be determined as the smaller value between the limit torque and the initial set torque. The final set torque of the engine is: T e_set =min( T e_set1 , T 1), where, T e_set This is the final set torque for the engine. T 1 represents the limiting torque when the battery is overcharged, which is calculated based on the sum of the battery's maximum power, the actual power of the first range extender motor, and the power required by the hydraulic system. T 1=9550 ( P Bmax + P mt_act + P h ) / n 1_set .

[0049] The embodiments of this application determine the upper limit of the torque of the first range extender motor based on the maximum discharge capacity of the battery, and further determine the set torque of the engine according to the problems that may occur during the control process. This can take into account the power generation needs while prioritizing the efficiency of loading operations. In the case of inaccurate hydraulic power calculation, it can improve the speed stability and anti-disturbance ability of the rotating shaft and reduce coupling risks.

[0050] When the first range extender motor acts as the speed control unit, and the dual-motor-hydraulic coaxial series range extender system uses the standard power generation method, the misalignment of the torque directions of the first and second range extenders affects the coupling. If the second range extender motor generates negative torque, the torque limit of the first range extender motor is zero, meaning positive torque is not allowed. Furthermore, compared to economical power generation, the engine's load-carrying capacity decreases, and with the first range extender motor's torque limit at zero, it lacks positive speed control capability. In this situation, an open torque compensation strategy is implemented for the components. When the first range extender motor has speed control capability, load adaptation is performed. However, when the hydraulic power is high and the first range extender motor needs to generate positive torque for acceleration, its torque is limited to zero, resulting in a temporary speed drop. The engine then compensates for positive torque based on the speed difference, and the second range extender motor reduces negative torque based on the speed difference. The purpose of the torque compensation strategy is to improve the range extender's power load response and reduce the impact of inaccurate hydraulic power calculations on speed control. Based on this, in this embodiment of the application, optionally, the step of allocating the set torque of the first range extender motor, the second range extender motor, and the engine according to the current operating information and the first required power includes: determining whether the second range extender motor outputs negative torque; if not, returning to the step of determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system according to the first required power; if the second range extender motor outputs negative torque, determining that the upper limit of the torque of the first range extender motor is zero; calculating the set torque of the second range extender motor according to the difference between the set speed and the actual speed of the first range extender motor and the first required power; determining the initial set torque of the engine according to the sum of the first required power and the second required power of the hydraulic system and the difference between the set speed and the actual speed of the first range extender motor; calculating the limiting torque when the battery is overcharged, and determining that the set torque of the engine is the smaller value between the limiting torque and the initial set torque.

[0051] To allocate the first required power to the first and second range extenders, it is first necessary to determine whether the second range extender outputs negative torque. If not, return to the step of determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system based on the first required power. If the second range extender outputs negative torque, the first range extender is not allowed to output positive torque, thus determining that the upper limit of the torque of the first range extender is zero. The set torque of the second range extender is allocated to 1 / 2 of the first required power. The remaining 1 / 2 of the generated torque and load changes are adaptively controlled by the first range extender through speed and torque control. Simultaneously, based on a torque compensation strategy, when the first range extender is under heavy load and the actual hydraulic power is high, the negative torque of the second range extender can be reduced through a torque coefficient. Therefore, the set torque of the second range extender can be calculated based on the difference between the set speed and the actual speed of the first range extender and the first required power. T 2_set = f 2( n 1_set - n 1_act ) 9550 P RE / 2 n 1_set ,in, T 2_set The set torque for the second range extender motor. f 2 represents a coefficient, the specific value of which can be set as needed. The engine torque setting is mainly based on a torque compensation strategy, which can increase the engine's positive torque by using the torque coefficient when the first range extender motor is under load and the actual hydraulic power is too high. Optionally, the initial set torque of the engine can be determined based on the sum of the first required power and the second required power of the hydraulic system, and the difference between the set speed and the actual speed of the first range extender motor. T e_set1 : T e_set1 = f e ( n 1_set - n 1_set ) 9550 ( P h + P RE ) / n 1_set , f eThis is a coefficient, and its specific value can be set as needed. To limit the lower limit of the torque of the first range extender motor and reduce the risk of battery overcharging, the engine torque is limited. Specifically, the limiting torque when the battery is overcharged can be calculated, and the set torque of the engine can be determined as the smaller value between the limiting torque and the initial set torque. The final set torque of the engine is: T e_set =min( T e_set1 , T 1), where, T e_set This is the final set torque for the engine. T 1 represents the limiting torque when the battery is overcharged, which is calculated based on the sum of the battery's maximum power, the actual power of the first range extender motor, and the power required by the hydraulic system. T 1=9550 ( P Bmax + P mt_act + P h ) / n 1_set .

[0052] This application embodiment determines the upper limit of the torque of the first range extender motor based on the influence of the torque direction of the first and second range extender motors on the coupling, allocates a certain proportion of the first required power to the second range extender motor, and further determines the set torque of the engine based on possible problems in the control process. It can prioritize ensuring the efficiency of loading operations while taking into account the power generation needs. In the case of inaccurate hydraulic power calculation, it can improve the speed stability and anti-disturbance ability of the rotating shaft and reduce coupling risks.

[0053] When the dual-motor-hydraulic coaxial series range extender system is operating in the second control mode, the engine performs the power generation point shift and load adaptation. The torque adjustment unit includes a first range extender motor and a second range extender motor, which means that the power generation torque corresponding to the first demand power needs to be distributed to the first range extender motor and the second range extender motor. Based on this, in this embodiment, optionally, if the dual-motor-hydraulic coaxial series range extender system operates in a second control mode, the second control mode being engine speed control and torque control of the first and second range extenders; the step of allocating power according to the current operating information and the first required power to obtain the set torque of the torque adjustment unit includes: obtaining the total set torque of the first and second range extenders according to the current operating information and the first required power; determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system according to the first required power, the power generation mode including an economical power generation mode and a standard power generation mode, the economical power generation mode being power generation by the first range extender, and the standard power generation mode being power generation by the first and second range extenders; if the dual-motor-hydraulic coaxial series range extender system adopts the economical power generation mode, then the set torque of the first range extender is determined as the total set torque; if the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation mode, then the total set torque is allocated to the first and second range extenders at a preset ratio.

[0054] If the dual-motor-hydraulic coaxial series range extender system operates in the second control mode, the first and second range extenders provide the torque for power generation. To allocate torque to the first and second range extenders, their total torque needs to be obtained. Therefore, the total set torque of the first and second range extenders is first obtained based on the current operating information and the first power demand. After obtaining the total set torque, the first power demand is compared with a power threshold. If the first power demand is less than the power threshold, economic power generation is determined. If the first power demand is greater than or equal to the power threshold, standard power generation is determined. If the dual-motor-hydraulic coaxial series range extender system uses economic power generation, the set torque of the first range extender is determined to be the total set torque. T 1_set = T m_set， T 2_set =0, where, T 1_set The set torque for the first range extender motor. T 2_set The set torque for the second range extender motor. T m_setThis is the total set torque for the first and second range extender motors. If the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation method, the total set torque is distributed to the first and second range extender motors according to a preset ratio. The preset ratio k takes a value between 0 and 1, and the specific value can be set as needed, without specific limitations here. After power distribution according to the preset ratio k, the set torques of the first and second range extender motors are respectively: T 1_set =k T m_set， T 2_set =(1-k) T m_set .

[0055] The embodiments of this application first obtain the total set torque of the first range extender motor and the second range extender motor, and then perform specific torque distribution on the first range extender motor and the second range extender motor according to the power generation method, so as to make the most of the high-efficiency working range of the motor and improve the energy conversion rate.

[0056] Obtaining the total set torque of the first and second range extender motors requires consideration not only of the initial power demand to be allocated, but also of potential issues during control, such as battery overcharging and over-discharging, operational efficiency, coupling risks, and inaccurate hydraulic power estimation. Therefore, in this embodiment, optionally, obtaining the total set torque of the first and second range extender motors based on the current operating information and the initial power demand includes: calculating the first total set torque of the first and second range extender motors based on the initial power demand and the set speed; correcting the first total set torque based on the difference between the engine's set speed and actual speed during the load-bearing process to obtain a second total set torque of the first and second range extender motors; and correcting the second total set torque based on the total current of the hydraulic pump displacement during the lifting operation to obtain the final total set torque of the first and second range extender motors.

[0057] First, it is necessary to ensure that the total torque output of the first and second range extender motors meets the charging requirement of the first required power. Then, the first total set torque of the first and second range extender motors can be calculated based on the first required power and the set speed. T m_set1 The first total set torque is calculated using the following formula. T m_set1 : T m_set1 =9550 P RE / n e_set .

[0058] Considering that the negative torque of the motor can be appropriately reduced to improve the engine's responsiveness during load loading, thus enabling rapid power point transition, the first total set torque can be corrected based on the difference between the engine's set speed and actual speed during the load loading process, resulting in a second total set torque for the first and second range extender motors. Specifically, the following formula is used to calculate the first total set torque. T m_set1 The calibration is performed to obtain the second total set torque. T m_set2 : T m_set2 = f 1( n e_set - n e_act ) T m_set1 ,in, f 1 represents the corresponding reference coefficient, which can be freely set and adjusted as needed. n e_set The set speed for the engine. n e_act This represents the actual engine speed.

[0059] Based on the identification of the work operation, and by recognizing the displacement current, the generator power can be reduced in advance to ensure the operation, preventing excessive hydraulic load and insufficient engine torque output that would lower the engine speed and sacrifice work efficiency. The lifting process can be identified using angle sensors and displacement sensors on the boom and bucket cylinders, offering higher accuracy. Thus, the total hydraulic pump displacement current can be calculated beforehand. i p Then, the second total set torque is corrected based on the total current of the hydraulic pump displacement to obtain the final total set torque of the first and second range extender motors. Specifically, the following formula is used to calculate the second total set torque. T m_set2 After calibration, the final total set torque of the first and second range extender motors is obtained. T m_set : T m_set = f i ( i p ) T m_set2 ,in, fi The corresponding reference coefficients can be freely set and adjusted as needed.

[0060] In the torque distribution process, this application fully considers the rapid shift of the power point during loading and the work efficiency during lifting operations, accurately obtains the total set torque of the first and second range extenders, and facilitates specific torque distribution to the first and second range extenders. It can prioritize loading efficiency while also taking into account power generation needs. In the case of inaccurate hydraulic power calculation, it can improve the speed stability and anti-disturbance capability of the rotating shaft and reduce coupling risks.

[0061] It should be noted that the first and second range extender motors mentioned above are interchangeable. That is, in other embodiments of this application, in the first control mode, the second range extender motor can be speed-torque controlled, and the first range extender motor is torque controlled.

[0062] After determining the set speeds and torques of the first range extender motor, the second range extender motor, and the engine, corresponding control signals can be generated. Specifically, the output signals of the range extender control unit (RCU) include a first control signal for the first range extender motor, a second control signal for the second range extender motor, and a third control signal for the engine. The first control signal includes the control mode, set speed, and set torque of the first range extender motor. The second control signal includes the control mode, set speed, and set torque of the second range extender motor. The third control signal includes the control mode, set speed, and set torque of the engine. Considering all the above, the first, second, and third control signals can be as follows:

[0063] The first control signal may specifically include: Motor 1 control modes: Mode 1 is speed and torque control, Mode 2 is torque control. Motor 1 set torque: Mode 1 is T 1_set_max Mode 2 is T 1_set Motor 1 speed setting: Mode 1 is n 1_set Mode 2 is 0.

[0064] The second control signal may specifically include: Motor 2 control modes: Mode 1 is torque control, Mode 2 is torque control Motor 2 torque setting: Mode 1 is T 2_set Mode 2 is T 2_set Motor 2 speed setting: 0 for mode 1, 0 for mode 2.

[0065] The third control signal may specifically include: Engine control modes: Mode 1 is torque control, Mode 2 is speed control. Engine torque setting: Mode 1 is T e_set Mode 2 is 0 Engine set speed: Mode 1 is 0, Mode 2 is... n e_set .

[0066] The range extender control unit (RCU) integrates the output signals into a predetermined message and transmits it to the first motor control unit (MCU1), the second motor control unit (MCU2), and the engine control unit (ECU) to control the operation of the first range extender motor, the second range extender motor, and the engine.

[0067] The following examples illustrate the specific implementation process of the power coordination control method for the dual-motor-hydraulic coaxial series range extender system according to embodiments of this application, such as... Figure 3 As shown, motor 1 is the first range extender motor, and motor 2 is the second range extender motor; the power coordination control process of the dual-motor-hydraulic coaxial series range extender system includes: Step 100: Begin.

[0068] Step 101: RCU input signal.

[0069] The input signal for power coordination control of the range extender control unit (RCU) is obtained. This input signal is the current operating information of the dual-motor-hydraulic coaxial series range extender system, which mainly includes battery SOC, key power, actual engine speed and torque, actual speed and torque of the first and second range extender motors, battery power limit of BMS, hydraulic pump pressure signal, total hydraulic pump displacement current, total power requirement of hydraulic system, and minimum speed requirement of hydraulic system.

[0070] Step 102: Calculate the fixed-point power generation demand of the range extender P RE .

[0071] Based on the battery SOC (State of Charge) decision-making power of the range extender, the fixed-point power point located within the engine's economic range can be directly found. The power generation demand at this fixed-point power point is the first required power of the dual-motor-hydraulic coaxial series range extender system. P RE .

[0072] Step 103: Determine control mode 1. If yes, proceed to step 104; otherwise, proceed to step 117.

[0073] The control mode of the dual-motor-hydraulic coaxial series range extender system put into use is pre-calibrated, and it can be directly determined whether the calibrated control mode is the first control mode, i.e., control mode 1.

[0074] Step 104: Based on the range extender's power output, look up the table to set the speed of motor 1. n 1.

[0075] You can directly look up the table showing the relationship between the required power and the set speed of motor 1 to obtain the set speed of motor 1 corresponding to the first required power. n 1. This set speed n 1 is the initial set speed of motor 1.

[0076] Step 105: Determine the required speed of the hydraulic system n h .

[0077] Obtain the required speed of the hydraulic system n h The method of obtaining it can be any existing method, or it can be obtained through direct detection; there are no restrictions here.

[0078] Step 106: Calculate the final set speed of motor 1 n 1_set =max( n 1, n h ).

[0079] Final set speed of motor 1 n 1_set Updated to the initial speed setting and hydraulic system required speed. n h The larger one.

[0080] Step 107: Determine the required power P RE >= P C If yes, proceed to step 112; otherwise, proceed to step 108.

[0081] The first required power P RE With power threshold P C Compare them. If the first required power... P RE Greater than or equal to the power threshold P C If the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation method, proceed to step 112. If the first required power... P RE Less than the power threshold PC If the dual-motor-hydraulic coaxial series range extender system adopts an economical power generation method, then proceed to step 108.

[0082] Step 108: Limit the upper limit of torque of motor 1 T 1_set_max =9550 ( P Bmax - P mt_act ) / n 1_set .

[0083] When using an economical power generation method in a dual-motor-hydraulic coaxial series range extender system, the upper limit of the torque of motor 1 is first calculated. T 1_set_max : T 1_set_max =9550 ( P Bmax - P mt_act ) / n 1_set .

[0084] Step 109: Calculate the generating torque of motor 2 T 2_set =0.

[0085] When the dual-motor-hydraulic coaxial series range extender system adopts an economical power generation method, only motor 1 generates electricity, which is the set torque of motor 2. T 2_set It is 0.

[0086] Step 110: Calculate the initial set torque of the engine T e_set1 =9550 ( P h + P RE ) / n 1_set .

[0087] The initial set torque of the engine can be determined based on the total power demand of the range-extended load: T e_set1 =9550 ( P h + P RE ) / n 1_set .

[0088] Step 111: Prevent battery overcharging from limiting engine torqueT e_set =min( T e_set1 , T 1).

[0089] Calculate the limiting torque when the battery is overcharged. T 1: T 1=9550 ( P Bmax + P mt_act + P h ) / n 1_set Then determine the engine's final set torque. T e_set =min( T e_set1 , T 1) It can prevent the battery from being overcharged while meeting charging requirements.

[0090] Step 112: Determine if motor 2 is generating electricity. T 2_act <0. If yes, proceed to step 113; otherwise, return to step 107.

[0091] That is, determine whether motor 2 outputs negative torque. If so, proceed to step 113; otherwise, return to step 107.

[0092] Step 113: Limit the upper limit of torque of motor 1 T 1_set_max =0.

[0093] If motor 2 outputs negative torque, and motor 1 is not allowed to output positive torque, then the upper limit of the torque of motor 1 can be determined to be zero. T 1_set_max =0.

[0094] Step 114: Calculate the generating torque T of motor 2 2_set = f 2( n 1_set - n 1_set ) 9550 P RE / 2 n 1_set .

[0095] The set torque of the second range extender motor is allocated to half of the first required power. The set torque of the second motor is calculated based on the difference between the set speed and the actual speed of the first motor and the first required power.T 2_set = f 2( n 1_set - n 1_act ) 9550 P RE / 2 n 1_set , f 2 is a coefficient, and the specific value can be set as needed.

[0096] Step 115: Calculate the engine set torque T e_set1 = f e ( n 1_set - n 1_set ) 9550 ( P h + P RE ) / n 1_set .

[0097] First, based on the primary power requirement... P RE With the second power demand of the hydraulic system P h The initial set torque of the engine is determined by the sum of the set speed and the difference between the set speed and the actual speed of motor 1. T e_set1 : T e_set1 = f e ( n 1_set - n 1_set ) 9550 ( P h + P RE ) / n 1_set , f e This is a coefficient, and the specific value can be set as needed.

[0098] Step 116: Prevent battery overcharging from limiting engine torque T e_set =min( T e_set1 ,T 1).

[0099] To prevent battery overcharging, the limiting torque when overcharging occurs is calculated. T 1: T 1=9550 ( P Bmax + P mt_act + P h ) / n 1_set Then, the engine's set torque is determined to be the smaller value between the limit torque and the initial set torque, i.e. T e_set =min( T e_set1 , T 1).

[0100] Step 117: Look up the engine set speed based on the range extender's power output. n e .

[0101] You can directly look up the table showing the relationship between required power and engine set speed to obtain the engine set speed corresponding to the first required power. n e The set speed n e As the initial set speed of the engine.

[0102] Step 118: Determine the required speed of the hydraulic system n h .

[0103] Obtain the required speed of the hydraulic system n h The method of obtaining it can be any existing method, or it can be obtained through direct detection; there are no restrictions here.

[0104] Step 119: Calculate the final engine set speed n e_set =max( n e , n h ).

[0105] The engine's final set speed n e_set Updated to the initial speed setting and hydraulic system required speed. n h The larger one.

[0106] Step 120: Calculate the total set torque of the two motors Tm_set1 =9550 P RE / n e_set .

[0107] Calculate the first total set torque of motor 1 and motor 2 based on the first required power and set speed. T m_set1 The first total set torque is calculated using the following formula. T m_set1 : T m_set1 =9550 P RE / n e_set .

[0108] Step 121: Dual motor total torque correction during load loading T m_set2 = f 1( n e_set - n e_act ) T m_set1 .

[0109] During load testing, the negative torque of the electric motor can be appropriately reduced to improve engine responsiveness and achieve rapid power point transition. Specifically, the following formula is used to calculate the first total set torque. T m_set1 The calibration is performed to obtain the second total set torque. T m_set2 : T m_set2 = f 1( n e_set - n e_act ) T m_set1 ,in, f 1 represents the corresponding reference coefficient, which can be freely set and adjusted as needed. n e_set The set speed for the engine. n e_act This represents the actual engine speed.

[0110] Step 122: Calculate the total current of the hydraulic pump displacement. i p .

[0111] Existing methods can be used to calculate the total current of the hydraulic pump displacement. i p Alternatively, it can be obtained directly through detection; no restrictions are imposed here.

[0112] Step 123: Dual motor total torque correction during lifting process T m_set = f i ( i p ) T m_set2 .

[0113] Based on the identification of the work operation, and by identifying the displacement and current, the generator power can be reduced in advance to ensure the operation, preventing excessive hydraulic load and insufficient engine torque output that would lower the engine speed and sacrifice work efficiency. The second total set torque is calculated using the following formula. T m_set2 After calibration, the final total set torque of the first and second range extender motors is obtained. T m_set : T m_set = f i ( i p ) T m_set2 .

[0114] Step 124: Determine the required power P RE >= P C If yes, proceed to step 126; otherwise, proceed to step 125.

[0115] The first required power P RE With power threshold P C Compare them. If the first required power... P RE Greater than or equal to the power threshold P C If the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation method, proceed to step 126. If the first required power... P RE Less than the power threshold P C If the dual-motor-hydraulic coaxial series range extender system adopts an economical power generation method, then proceed to step 125.

[0116] Step 125: Distribute the set torque of the motor T 1_set = T m_set， T 2_set =0.

[0117] The dual-motor-hydraulic coaxial series range extender system adopts an economical power generation method, determining the set torque of motor 1 as the total set torque, i.e. T 1_set = T m_set， T 2_set =0.

[0118] Step 126: Distribute electrical setting torque T 1_set =k T m_set， T 2_set =(1-k) T m_set .

[0119] The total set torque is distributed to motor 1 and motor 2 according to a preset ratio k. After power distribution according to the preset ratio k, the set torques of the first range extender motor and the second range extender motor are respectively: T 1_set =k T m_set， T 2_set =(1-k) T m_set .

[0120] Step 127: RCU output signal.

[0121] After determining the set speed and set torque of the first range extender motor, the second range extender motor, and the engine, corresponding control signals can be generated. The output signals of the range extender control unit (RCU) include various control signals, which are transmitted to the first motor control unit (MCU1), the second motor control unit (MCU2), and the engine control unit (ECU) to control the operation of the first range extender motor, the second range extender motor, and the engine.

[0122] Step 128: End.

[0123] The power coordination control method of the dual-motor-hydraulic coaxial series range extender system in this application embodiment performs reasonable power flow distribution and mode control on the dual-motor-hydraulic coaxial series range extender system configuration. It prioritizes loading operation efficiency while also considering power generation needs. In cases of inaccurate hydraulic power calculation, it improves the rotational shaft speed stability and anti-disturbance capability, reducing coupling risks. Two control strategies are employed: Mode 1 uses engine torque control, motor 1 speed torque control, and motor 2 torque control. To address inaccurate hydraulic power estimation, the speed-controlled and torque-controlled motors provide power compensation to stabilize the speed. During range extender power loading and economic / standard power generation, the torque direction between the two motors is coordinated to prevent abnormal coupling speed fluctuations. Simultaneously, to avoid battery overcharging and over-discharging issues caused by motor 1 speed adjustment, an upper limit for motor 1 torque is set based on the power generation mode, and the engine torque is limited based on the battery charging and discharging power. Conversely, a lower limit for motor 1 torque is set to achieve controllable speed regulation. Mode 2 uses engine speed control and torque control for both motors 1 and 2. Based on the identification of the work being performed, the power generation is reduced during lifting to ensure operational efficiency. For the two control modes, this application provides a torque compensation strategy to improve system response when the range extender is under power load, and to coordinate torque to improve speed stability. This application also addresses potential issues during control, such as low-probability battery overcharging and over-discharging, operational efficiency problems, coupling risks, and inaccurate hydraulic power estimation, by implementing avoidance measures to enhance the robustness of the control strategy under this configuration and reduce risk points.

[0124] In summary, the power coordination control method for the dual-motor-hydraulic coaxial series range extender system of this application collects the current operating information of the dual-motor-hydraulic coaxial series range extender system and determines the first required power of the dual-motor-hydraulic coaxial series range extender system; determines the set speed of the speed regulating unit based on the first required power, the speed regulating unit being either the first range extender motor or the engine; performs power allocation based on the current operating information and the first required power, and obtains the set torque of the torque regulating unit, the torque regulating unit including at least one of the first range extender motor, the second range extender motor, and the engine; generates control signals based on the set speed and the set torque of each torque regulating unit to control the operation of the first range extender motor, the second range extender motor, and the engine. This method prioritizes loading operation efficiency while also considering power generation needs. In cases where hydraulic power calculation is inaccurate, it can improve the speed stability and anti-disturbance capability of the rotating shaft, and reduce coupling risks.

[0125] In one exemplary embodiment of this specification, a power coordination control device for a dual-motor-hydraulic coaxial series range extender system is also provided, applied to the range extender control unit. The dual-motor-hydraulic coaxial series range extender system includes: a first range extender motor, a second range extender motor, and an engine. The engine is coaxially connected to the first and second range extender motors via a coupling. The first and second range extender motors are coaxially connected in series with the hydraulic system. Figure 4 As shown, the power coordination control device 400 of the dual-motor-hydraulic coaxial series range extender system includes: The information acquisition module 401 is used to acquire the current operating information of the dual-motor-hydraulic coaxial series range extender system and determine the first required power of the dual-motor-hydraulic coaxial series range extender system. The speed control module 402 is used to determine the set speed of the speed regulating unit according to the first required power, wherein the speed regulating unit is the first range extender motor or the engine. The torque control module 403 is used to allocate power according to the current operating information and the first required power, and to obtain the set torque of the torque adjustment unit. The torque adjustment unit includes at least one of the first range extender motor, the second range extender motor, and the engine. The output control module 404 is used to generate control signals based on the set speed and the set torque of each of the torque adjustment units, so as to control the operation of the first range extender motor, the second range extender motor and the engine.

[0126] In one specific implementation, if the dual-motor-hydraulic coaxial series range extender system operates in a first control mode, the first control mode being engine torque control, first range extender motor speed-torque control, and second range extender motor torque control; the torque control module 403 is used to: determine the power generation mode of the dual-motor-hydraulic coaxial series range extender system based on the first required power, the power generation mode including an economical power generation mode and a standard power generation mode, the economical power generation mode being power generation by the first range extender motor, and the standard power generation mode being power generation by both the first and second range extender motors; if the dual-motor-hydraulic coaxial series range extender system adopts the economical power generation mode, then the set torque of the first range extender motor and the engine is allocated according to the current operating information and the first required power; if the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation mode, then the set torque of the first range extender motor, the second range extender motor, and the engine is allocated according to the current operating information and the first required power.

[0127] In one specific embodiment, the torque control module 403 is further configured to: determine the upper limit of the torque of the first range extender motor based on the maximum discharge capacity of the battery and the actual torque of the first range extender motor; determine the initial set torque of the engine according to the total power demand of the range extender load, wherein the range extender load includes the first range extender motor, the second range extender motor and the hydraulic system, and the total power demand of the range extender load is the sum of the first power demand and the second power demand of the hydraulic system; calculate the limiting torque when the battery is overcharged, and determine the set torque of the engine to be the smaller value between the limiting torque and the initial set torque.

[0128] In one specific embodiment, the torque control module 403 is further configured to: determine whether the second range extender motor outputs negative torque; if not, return to the step of determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system based on the first required power; if the second range extender motor outputs negative torque, determine that the upper limit of the torque of the first range extender motor is zero; calculate the set torque of the second range extender motor based on the difference between the set speed and the actual speed of the first range extender motor and the first required power; determine the initial set torque of the engine based on the sum of the first required power and the second required power of the hydraulic system and the difference between the set speed and the actual speed of the first range extender motor; calculate the limiting torque when the battery is overcharged, and determine that the set torque of the engine is the smaller value between the limiting torque and the initial set torque.

[0129] In one specific implementation, if the dual-motor-hydraulic coaxial series range extender system operates in a second control mode, the second control mode being engine speed control and torque control of the first and second range extenders; the torque control module 403 is further configured to: obtain the total set torque of the first and second range extenders based on the current operating information and the first required power; determine the power generation mode of the dual-motor-hydraulic coaxial series range extender system based on the first required power, the power generation mode including an economical power generation mode and a standard power generation mode, the economical power generation mode being power generation by the first range extender, and the standard power generation mode being power generation by both the first and second range extenders; if the dual-motor-hydraulic coaxial series range extender system adopts the economical power generation mode, then determine the set torque of the first range extender as the total set torque; if the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation mode, then allocate the total set torque to the first and second range extenders at a preset ratio.

[0130] In one specific embodiment, the torque control module 403 is further configured to: calculate a first total set torque of the first range extender motor and the second range extender motor based on the first required power and the set speed; correct the first total set torque based on the difference between the set speed and the actual speed of the engine during the load-bearing process to obtain a second total set torque of the first range extender motor and the second range extender motor; and correct the second total set torque based on the total current of the hydraulic pump displacement during the lifting operation to obtain the final total set torque of the first range extender motor and the second range extender motor.

[0131] In one specific embodiment, the speed control module 402 is used to: determine the control mode of the dual-motor-hydraulic coaxial series range extender system; if the dual-motor-hydraulic coaxial series range extender system operates in a first control mode, then determine the target speed of the first range extender motor based on the first required power, and determine the set speed of the first range extender motor in combination with the required speed of the hydraulic system, wherein the first control mode is the engine torque control, the first range extender motor speed-torque control, and the second range extender motor torque control; if the dual-motor-hydraulic coaxial series range extender system operates in a second control mode, then determine the target speed of the engine based on the first required power, and determine the set speed of the engine in combination with the required speed of the hydraulic system, wherein the second control mode is the engine speed control, and the torque control of the first and second range extenders.

[0132] Specific limitations regarding the power coordination control device for the dual-motor-hydraulic coaxial series range extender system can be found in the above section on the limitations of the power coordination control method for the dual-motor-hydraulic coaxial series range extender system, and will not be repeated here. Each module in the power coordination control device of the aforementioned dual-motor-hydraulic coaxial series range extender system can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0133] Regarding the apparatus in the above embodiments, the specific manner in which each unit performs its operation has been described in detail in the embodiments concerning the power coordination control method for a dual-motor-hydraulic coaxial series range extender system, and will not be elaborated upon here.

[0134] Figure 5 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application.

[0135] For example, such as Figure 5As shown, the vehicle 500 includes a memory 501 and a processor 502. The memory 501 stores an executable computer program 5011, and the processor 502 is used to call and execute the executable computer program 5011 to perform a power coordination control method for a dual-motor-hydraulic coaxial series range extender system.

[0136] This embodiment can divide the vehicle into functional modules according to the above method embodiment. For example, each function can be assigned to a separate module, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0137] When each function is divided into modules, the vehicle may include: an information acquisition module, a speed control module, a torque control module, and an output control module.

[0138] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0139] The vehicle provided in this embodiment is used to execute the power coordination control method of the above-described dual-motor-hydraulic coaxial series range extender system, and thus can achieve the same effect as the above implementation method.

[0140] When using integrated units, the vehicle may include a processing module and a storage module. The processing module is used to control and manage the vehicle's movements. The storage module is used to support the processing module in executing computer programs and processing data.

[0141] The processing module may be a processor or a controller, which can implement or execute various exemplary logic blocks, modules, and circuits as disclosed in this application. The processor may also be a combination of computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and microprocessors, etc., and the storage module may be a memory.

[0142] This embodiment also provides a computer-readable storage medium (including but not limited to disk storage, CD-ROM, optical storage, etc.) storing computer program code. When the computer program code is run on a computer, the computer executes the above-mentioned related method steps to realize the power coordination control method of the dual-motor-hydraulic coaxial series range extender system provided in the above embodiment. The computer-readable storage medium may include, but is not limited to, any type of disk, including floppy disks, optical disks, Digital Video Discs (DVDs), Compact Disc Read-Only Memory (CD-ROM), microdrives, and magneto-optical disks, read-only memory (ROM), random access memory (RAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), dynamic random access memory (DRAM), video random access memory (VRAM), flash memory devices, magnetic cards or optical cards, nanosystems (including molecular memory ICs), or any type of media or device suitable for storing instructions and / or data.

[0143] This embodiment also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned related steps to realize the power coordination control method for a dual-motor-hydraulic coaxial series range extender system provided in the above embodiment.

[0144] The beneficial effects of the above embodiments can be referred to the beneficial effects of the corresponding methods provided above, and will not be repeated here.

[0145] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0146] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0147] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0148] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0149] It should be understood that the qualifiers “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and are not intended to limit the scope of protection of this application.

[0150] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A power coordination control method for a dual-motor-hydraulic coaxial series range extender system, characterized in that, The dual-motor-hydraulic coaxial series range extender system includes: a first range extender motor, a second range extender motor, and an engine. The engine is coaxially connected to the first and second range extender motors via a coupling. The first and second range extender motors are coaxially connected in series with the hydraulic system. The method includes: Collect the current operating information of the dual-motor-hydraulic coaxial series range extender system and determine the first required power of the dual-motor-hydraulic coaxial series range extender system; The set speed of the speed regulating unit is determined based on the first required power, wherein the speed regulating unit is the first range extender motor or the engine; Power allocation is performed based on the current operating information and the first required power to obtain the set torque of the torque adjustment unit. The torque adjustment unit includes at least one of the first range extender motor, the second range extender motor, and the engine. Control signals are generated based on the set speed and the set torque of each of the torque adjustment units to control the operation of the first range extender motor, the second range extender motor, and the engine.

2. The method according to claim 1, characterized in that, If the dual-motor-hydraulic coaxial series range extender system operates in the first control mode, the first control mode being engine torque control, first range extender motor speed-torque control, and second range extender motor torque control; the step of allocating power according to the current operating information and the first required power, and obtaining the set torque of the torque adjustment unit, includes: The power generation mode of the dual-motor-hydraulic coaxial series range extender system is determined based on the first required power. The power generation mode includes an economical power generation mode and a standard power generation mode. The economical power generation mode is generated by the first range extender motor, and the standard power generation mode is generated by the first range extender motor and the second range extender motor. If the dual-motor-hydraulic coaxial series range extender system adopts an economical power generation method, then the set torque of the first range extender motor and the engine is allocated according to the current operating information and the first required power. If the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation method, then the set torque of the first range extender motor, the second range extender motor, and the engine is allocated according to the current operating information and the first required power.

3. The method according to claim 2, characterized in that, The step of allocating the set torque of the first range extender motor and the engine according to the current operating information and the first power demand includes: The upper limit of the torque of the first range extender motor is determined based on the maximum discharge capacity of the battery and the actual torque of the first range extender motor. The initial set torque of the engine is determined based on the total power demand of the range-extending load, wherein the range-extending load includes the first range-extending motor, the second range-extending motor, and the hydraulic system, and the total power demand of the range-extending load is the sum of the first power demand and the second power demand of the hydraulic system; Calculate the limiting torque when the battery is overcharged, and determine the set torque of the engine as the smaller value between the limiting torque and the initial set torque.

4. The method according to claim 2, characterized in that, The step of allocating set torques to the first range extender motor, the second range extender motor, and the engine based on the current operating information and the first power demand includes: Determine whether the second range extender motor outputs negative torque. If not, return to the step of determining the power generation mode of the dual-motor-hydraulic coaxial series range extender system based on the first required power. If the second range extender motor outputs negative torque, the upper limit of the torque of the first range extender motor is determined to be zero; The set torque of the second range extender motor is calculated based on the difference between the set speed and the actual speed of the first range extender motor and the first required power. The initial set torque of the engine is determined based on the sum of the first required power and the second required power of the hydraulic system, and the difference between the set speed and the actual speed of the first range extender motor. Calculate the limiting torque when the battery is overcharged, and determine the set torque of the engine as the smaller value between the limiting torque and the initial set torque.

5. The method according to claim 1, characterized in that, If the dual-motor-hydraulic coaxial series range extender system operates in the second control mode, the second control mode is the engine speed control, the first range extender motor and the second range extender motor torque control; The step of allocating power based on the current operating information and the first required power, and obtaining the set torque of the torque adjustment unit, includes: The total set torque of the first range extender motor and the second range extender motor is obtained based on the current operating information and the first required power. The power generation mode of the dual-motor-hydraulic coaxial series range extender system is determined based on the first required power. The power generation mode includes an economical power generation mode and a standard power generation mode. The economical power generation mode is generated by the first range extender motor, and the standard power generation mode is generated by the first range extender motor and the second range extender motor. If the dual-motor-hydraulic coaxial series range extender system adopts an economical power generation method, then the set torque of the first range extender motor is determined to be the total set torque; If the dual-motor-hydraulic coaxial series range extender system adopts the standard power generation method, the total set torque is distributed to the first range extender motor and the second range extender motor at a preset ratio.

6. The method according to claim 5, characterized in that, The step of obtaining the total set torque of the first range extender motor and the second range extender motor based on the current operating information and the first required power includes: Calculate the first total set torque of the first range extender motor and the second range extender motor based on the first required power and the set speed; Based on the load-bearing process, the first total set torque is corrected according to the difference between the set speed and the actual speed of the engine to obtain the second total set torque of the first range extender motor and the second range extender motor. Based on the lifting operation, the second total set torque is corrected according to the total current of the hydraulic pump displacement to obtain the final total set torque of the first range extender motor and the second range extender motor.

7. The method according to claim 1, characterized in that, Determining the set speed of the speed regulating unit based on the first required power includes: Determine the control mode of the dual-motor-hydraulic coaxial series range extender system; If the dual-motor-hydraulic coaxial series range extender system is operating in the first control mode, the target speed of the first range extender motor is determined according to the first required power, and the set speed of the first range extender motor is determined in combination with the required speed of the hydraulic system, wherein the first control mode is the engine torque control, the first range extender motor speed torque control, and the second range extender motor torque control. If the dual-motor-hydraulic coaxial series range extender system operates in the second control mode, the target speed of the engine is determined based on the first required power, and the set speed of the engine is determined in combination with the required speed of the hydraulic system, wherein the second control mode is engine speed control and torque control of the first range extender motor and the second range extender motor.

8. A power coordination control device for a dual-motor-hydraulic coaxial series range extender system, characterized in that, The dual-motor-hydraulic coaxial series range extender system includes: a first range extender motor, a second range extender motor, and an engine. The engine is coaxially connected to the first and second range extender motors via a coupling. The first and second range extender motors are coaxially connected in series with the hydraulic system. The device includes: The information acquisition module is used to collect the current operating information of the dual-motor-hydraulic coaxial series range extender system and determine the first required power of the dual-motor-hydraulic coaxial series range extender system. A speed control module is used to determine the set speed of the speed regulating unit based on the first required power, wherein the speed regulating unit is the first range extender motor or the engine; The torque control module is used to allocate power according to the current operating information and the first required power, and to obtain the set torque of the torque adjustment unit. The torque adjustment unit includes at least one of the first range extender motor, the second range extender motor, and the engine. The output control module is used to generate control signals based on the set speed and the set torque of each of the torque adjustment units, so as to control the operation of the first range extender motor, the second range extender motor and the engine.

9. A vehicle, characterized in that, The vehicles include: Memory, used to store executable computer programs; A processor for calling and running the executable computer program from the memory, such that the processor performs the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed, implements the method as described in any one of claims 1 to 7.

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