Tandem type hybrid power control system of heavy vehicle

Abstract

The invention discloses a tandem type hybrid power control system for a heavy vehicle, which adopts a mode that a battery is directly hung on a bus and is not provided with equipment such as DC-DC (Direct Current-Direct Current) and a brake resistor, so that the complexity of the system is simplified, and the production cost and the maintenance cost are reduced; an engine throttle control scheme, a generator rotating speed control scheme, a driving motor voltage control scheme and an energy management scheme are designed, and the control method for the series hybrid power system of the heavy vehicle is designed by combining the control schemes. According to the method, the engine is directly controlled according to the driving requirement, the generator and the driving motor are responsible for adjusting the system rotating speed and the voltage state, the characteristic that the motor is higher than the engine in regulation and control capacity is fully utilized, and the problem of system state instability caused by engine power response delay is solved. According to the control method for the hybrid power system of the heavy vehicle, the functions of driving, braking energy recovery and energy management can be achieved, and the operation efficiency of the hybrid power system is improved on the premise that the stability of the system is guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of hybrid vehicle, and in particular relates to a series hybrid vehicle control system for a heavy vehicle. Background Art

[0002] Hybrid vehicles are one of the main directions for the transformation and upgrading of the global automotive industry and green development. As a key force in engineering operations, non-structural road transportation and military applications, heavy-duty vehicles play an important role in social development and national defense construction. Therefore, the transformation of heavy-duty vehicles into hybrid vehicles has become the main development trend. The series hybrid system is one of the main power system configurations used in heavy-duty vehicles. The control method is the key to achieving the coordinated operation of the series hybrid system engine, motor and battery, and ensuring the efficient and stable driving of heavy-duty hybrid vehicles. Conducting research on series hybrid control systems suitable for heavy-duty vehicles is the current priority.

[0003] The current control methods for series hybrid powertrains of heavy-duty vehicles are mainly based on the control methods for series hybrid powertrains or extended-range hybrid powertrains of medium- and light-duty vehicles, such as generator voltage stabilization control methods, thermostat control methods, and power following control methods. However, compared with medium- and light-duty vehicles, heavy-duty vehicles have the characteristics of complex driving environments, high vehicle power levels, small battery energy ratios, and more prominent electromechanical coupling characteristics. When performing large-scale power regulation, it is difficult to ensure the system operation stability under maneuvering conditions using the coordinated control method for series hybrid powertrains of medium- and light-duty vehicles, resulting in increased fluctuations in electromechanical states such as engine speed and bus voltage, and even instability and shutdown. In order to solve the above problems and improve the maneuverability and stability of heavy-duty hybrid vehicles in complex driving environments, the present invention proposes a series hybrid power control system suitable for heavy-duty vehicles. Summary of the invention

[0004] The present invention aims to solve the technical problems existing in the background technology and provides a series hybrid power control system for a heavy-duty vehicle.

[0005] In order to solve the technical problem, the technical solution of the present invention is:

[0006] A heavy-duty vehicle series hybrid power control system, the control system comprising: an engine control module, an energy management module, a generator control module and a drive motor control module;

[0007] The engine control module is used to receive the accelerator pedal opening instruction, the brake pedal opening instruction and the battery SOC signal, and generate the engine throttle opening instruction after calculation and processing;

[0008] The energy management module is used to receive the accelerator pedal opening instruction and the battery SOC signal, and generate the generator target speed instruction after calculation and processing according to the engine efficiency MAP map;

[0009] The generator control module is used to receive the generator target speed command sent by the energy management module, collect the speed sensor feedback signal between the engine and the generator, and generate the generator torque command after calculation and processing;

[0010] The drive motor control module is used to receive an accelerator pedal opening instruction, a brake pedal opening instruction and a battery SOC signal, collect a voltage sensor feedback signal on a high-voltage DC bus, and generate a drive motor torque instruction after calculation and processing.

[0011] Furthermore, the engine control module is responsible for generating an engine throttle opening instruction, and the specific method includes:

[0012] First, read the accelerator pedal opening command, brake pedal opening command and battery SOC signal; then, determine whether the battery SOC is greater than the given reference SOC; if it is greater, it is considered that the battery does not need additional power supply and no throttle opening compensation is performed, that is, u com =0, otherwise it is considered that the battery needs additional power supply, then according to the formula u com =k1×(SOC ref -SOC) calculates the throttle opening compensation command, k1 is an adjustable constant coefficient, SOC ref is the reference value of the battery SOC, and further determines whether the brake pedal opening is greater than zero. If so, it is considered that the current vehicle has a braking demand, and the accelerator pedal opening command is forced to be converted to 0. Otherwise, the accelerator pedal opening command is converted into a control command u acc , according to the formula u thr =u acc +u com Calculate the engine throttle opening command u thr .

[0013] Furthermore, the energy management module is responsible for generating a target speed instruction of the generator, and the specific method includes:

[0014] First, read the accelerator pedal opening command and battery SOC signal; then, according to the formula P dem = k4 × accelerator pedal opening to calculate the driver's required power. k4 is the power coefficient under acceleration conditions, which can be calculated based on the system's maximum power. Next, according to the formula P char =k5×(SOC ref -SOC) calculates the required charging and discharging power of the battery, k5 is the battery charging and discharging power coefficient, which can be calculated based on the battery charging and discharging capacity. The next step is P all =Pdem +P char Calculate the total required power P according to the formula all ; Next, find the optimal operating speed of the engine according to the engine efficiency MAP diagram and the total required power, and convert it into the generator target speed; finally, output the generator target speed.

[0015] Furthermore, the generator control module is responsible for generating a generator torque command to control the generator and engine speed; the specific method includes:

[0016] First, read the generator target speed command and speed sensor signal sent by the energy management module, then determine whether the generator speed is greater than the target speed. If so, execute the generator speed control algorithm to generate the generator torque command u gm ; Otherwise, the generator torque command is set to 0, that is, u gm =0; Finally, the generator torque command u is output gm ; The generator speed control scheme is formed by the generator, the generator control module and the speed sensor.

[0017] Furthermore, the generator speed control algorithm adopts the PD algorithm, and the specific formula is as follows:

[0018]

[0019] In the formula, k p is the proportional coefficient of the PD control algorithm, k d is the differential coefficient of the PD control algorithm, e ω is the generator speed error, that is, e ω =Target speed - engine speed.

[0020] Furthermore, the drive motor control module is responsible for generating a drive motor torque instruction, and the specific method includes:

[0021] First, the accelerator pedal opening command, brake pedal opening command, battery SOC signal and voltage sensor signal are read; next, the drive motor torque constraint is calculated according to the accelerator pedal opening and brake pedal opening. The torque upper limit constraint is calculated according to T max = k2 × accelerator pedal opening, k2 is a constant coefficient greater than 0; the torque lower limit constraint is calculated according to T min = k3 × brake pedal opening calculation, k3 is a constant coefficient less than 0; the next step is to determine whether the brake pedal opening is greater than zero. If it is greater, then further determine whether the battery SOC is greater than the reference SOC ref Otherwise, determine whether the bus voltage is greater than the target bus voltage; if the battery SOC is greater than the reference SOC ref , the drive motor torque command u dmSet to 0 and proceed to the next step, otherwise follow the formula u dm = k4 × battery charging current upper limit to calculate the drive motor torque command u dm , k4 is a constant coefficient less than 0, further judging u dm >T min Is it true? If not, u dm Set to T min , otherwise go to the next step; if the bus voltage is greater than the target bus voltage, it does not hold, and the motor torque command u is driven dm Set to 0 and go to the next step, otherwise execute the drive motor control algorithm to generate the drive motor torque command u dm , further determine u dm >T min Is it true? If true, u dm Set to T max Otherwise, go directly to the next step; further, output the final drive motor rotation instruction u dm ; The voltage control scheme of the drive motor is formed by the drive motor, the drive motor control module and the voltage sensor.

[0022] Furthermore, the drive motor control algorithm adopts the PD control algorithm; the PD algorithm formula is as follows:

[0023]

[0024] In the formula, k pp is the proportional coefficient of the PD control algorithm, k dd is the differential coefficient of the PD control algorithm, e V is the DC bus voltage error, that is, e V = target voltage - voltage sensor feedback voltage.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] 1. The present invention designs a series hybrid power control system for heavy vehicles. The system adopts a method of directly hanging batteries on busbars and does not have DC-DC and brake resistors and other equipment, which simplifies the system complexity and reduces production and maintenance costs.

[0027] 2. The present invention designs an engine throttle control scheme, a generator speed control scheme, a drive motor voltage control scheme and an energy management scheme, and designs a heavy-duty vehicle series hybrid power system control method in combination with these control schemes. This method directly controls the engine according to driving demand, and the generator and drive motor are responsible for adjusting the system speed and voltage state, making full use of the characteristics that the motor has stronger control ability than the engine, and preventing problems such as system instability caused by engine power response delay.

[0028] 3. The present invention designs a control method for a heavy-duty vehicle hybrid power system, which can realize driving, braking energy recovery and energy management functions, and can improve the operating efficiency of the hybrid power system while ensuring system stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 , Series Hybrid Power Control System Diagram;

[0030] Figure 2 , engine throttle command generation logic diagram;

[0031] Figure 3 , generator torque command generation logic diagram;

[0032] Figure 4 , drive motor torque command generation logic diagram;

[0033] Figure 5 , energy management module control diagram. DETAILED DESCRIPTION

[0034] The specific implementation mode of the present invention is described below in conjunction with embodiments:

[0035] It should be noted that the structures, proportions, sizes, etc. shown in this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them, and are not used to limit the conditions under which the present invention can be implemented. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0036] At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of description and are not used to limit the scope of implementation of the present invention. Changes or adjustments to their relative relationships should be regarded as the scope of implementation of the present invention without substantially changing the technical content.

[0037] Embodiment 1:

[0038] The present invention provides a series hybrid power control system for a heavy-duty vehicle. The series hybrid power control system for a heavy-duty vehicle includes two parts: a series hybrid power system and a control system. Among them, the series hybrid power system is a solution in which a battery is directly connected to a DC bus. The control system includes four modules, namely, an engine control module, a generator control module, a drive motor control module and an energy management module. The engine control module has an engine throttle control function, and calculates an engine throttle control instruction based on an accelerator pedal opening signal, a brake pedal opening signal and a battery SOC signal; the generator control module has a generator speed control algorithm, and calculates a generator torque instruction based on a target speed instruction and a speed sensor feedback signal to achieve generator speed control; the drive motor control module has a drive motor voltage stabilization control algorithm, and calculates a drive motor torque instruction based on a voltage sensor signal, an accelerator pedal opening signal, a brake pedal opening signal and a battery SOC signal, and generates a driving force to drive the vehicle while stabilizing the high-voltage DC bus voltage; the energy management module has an engine operation range optimization function, and calculates the engine's optimal operating speed based on an accelerator pedal opening signal and a battery SOC signal, and refers to an engine efficiency MAP diagram to generate a generator target speed. The proposed coordinated control method for the series hybrid system directly receives the driver's driving demand from the engine, the generator and the drive motor stabilize the system state, and the energy management module is responsible for regulating the engine and generator operating speed. Since the dynamic response capability of the generator and the drive motor is higher than that of the engine, the proposed control method can solve the instability problem caused by the engine power response delay during high-power regulation of heavy vehicles, and at the same time improve the fuel economy of the system.

[0039] Embodiment 2:

[0040] In order to achieve the above-mentioned purpose, the present invention proposes a heavy-duty vehicle series hybrid power control system. Specifically, it includes a control system, a series hybrid power system and a vehicle. Figure 1As shown. The control system includes an engine control module, a generator control module, a drive motor control module and an energy management module. The engine control module receives an accelerator pedal opening instruction, a brake pedal opening instruction and a battery SOC signal, and generates an engine throttle opening instruction after calculation and processing; the generator control module receives a target speed instruction sent by the energy management module, collects the speed sensor feedback signal between the engine and the generator, and generates a torque instruction of the generator after calculation and processing; the drive motor control module receives an accelerator pedal opening instruction, a brake pedal opening instruction and a battery SOC signal, collects the voltage sensor feedback signal on the high-voltage DC bus, and generates a drive motor torque instruction after calculation and processing; the energy management module receives an accelerator pedal opening instruction and a battery SOC signal, and generates a generator target speed instruction after calculation and processing according to the engine efficiency MAP diagram. The series hybrid system mainly includes several components such as an engine, a generator, a speed sensor, a battery, a voltage sensor, a drive motor and a transmission system, wherein the engine refers to its body and its controller (ECU), the generator refers to its body and its controller (GCU), the battery refers to its body and its controller (BMS) and the drive motor refers to its body and its controller (MCU). The engine and the generator are mechanically connected; the speed sensor is installed on the mechanical structure between the engine and the generator, or integrated on the engine and the generator; the generator, the battery and the drive motor are connected through a high-voltage DC bus; the voltage sensor is installed on the high-voltage DC bus between the generator, the battery and the drive motor, or integrated on the generator, the battery and the drive motor. The drive motor and the transmission system are mechanically connected. The transmission system has functions such as speed increase / deceleration and speed change. There is a mechanical connection between the transmission system and the vehicle body, and the output torque of the transmission system can be transmitted to the wheels of the vehicle through the mechanical connection to drive the vehicle.

[0041] The engine control module is responsible for generating the engine throttle opening instruction. The specific calculation process is as follows: Figure 2 As shown. First, read the accelerator pedal opening command, brake pedal opening command and battery SOC signal. Then, determine whether the battery SOC is greater than the given reference SOC. If the above proposition is true, it is considered that the battery does not need additional power supply and does not compensate for the throttle opening, that is, u com =0, otherwise it is considered that the battery needs additional power supply, then according to the formula u com =k1×(SOC ref -SOC) calculates the throttle opening compensation command, k1 is an adjustable constant coefficient, SOC refis the reference value of the battery SOC. Further, it is determined whether the brake pedal opening is greater than zero. If the above proposition is true, it is considered that the current vehicle has a braking demand, and the accelerator pedal opening command is forced to be converted to 0, otherwise the accelerator pedal opening command is converted into a control command u acc Next, according to the formula u thr =u acc +u com Calculate the throttle command u thr The engine and the engine control module constitute the throttle control solution of the engine.

[0042] The generator control module is responsible for generating the generator torque command to control the generator and engine speed. The specific calculation process is as follows: Figure 3 As shown. First, read the generator target speed command and speed sensor signal sent by the energy management module. Then, determine whether the generator speed is greater than the target speed. If the above proposition is true, execute the generator speed control algorithm to generate the generator torque command u gm .exist Figure 3 An example of a speed control scheme based on the PD algorithm is given in , but it is not limited to the PD algorithm. If the above proposition is not true, the generator torque command is set to 0, that is, u gm = 0. Finally, the generator torque command u is output gm The generator, generator control module and speed sensor constitute the generator speed control scheme. The PD algorithm formula is as follows:

[0043]

[0044] In the formula, k p is the proportional coefficient of the PD control algorithm, k d is the differential coefficient of the PD control algorithm, e ω is the generator speed error, that is, e ω =Target speed - engine speed.

[0045] The drive motor control module is responsible for generating the drive motor torque command. The specific calculation process is as follows: Figure 4 As shown. First, read the accelerator pedal opening command, brake pedal opening command, battery SOC signal and voltage sensor signal. Next, calculate the drive motor torque constraint according to the accelerator pedal opening and brake pedal opening. The torque upper limit constraint is calculated according to T max = k2 × accelerator pedal opening calculation (k2 is a constant coefficient greater than 0); the torque lower limit constraint is based on T min = k3 × brake pedal opening calculation (k3 is a constant coefficient less than 0). Next, determine whether the brake pedal opening is greater than zero. If the above proposition is true, further determine whether the battery SOC is greater than the reference SOC.ref Otherwise, determine whether the bus voltage is greater than the target bus voltage. If the battery SOC is greater than the reference SOC ref The proposition is established, and the driving motor torque command u dm Set to 0 and proceed to the next step, otherwise follow the formula u dm = k4 × upper limit of battery charging current (k4 is a constant coefficient less than 0) to calculate the drive motor torque command u dm , further determine u dm >T min Is it true? If the proposition is not true, u dm Set to T min , otherwise go to the next step. If the bus voltage is greater than the target bus voltage, the proposition is not true, and the drive motor torque command u dm Set to 0 and go to the next step, otherwise execute the drive motor PD control algorithm to generate the drive motor torque command u dm , further determine u dm >T min Is it true? If the proposition is true, u dm Set to T max Otherwise, go directly to the next step. Further, output the final drive motor rotation instruction u dm .exist Figure 2 .4 gives an example of a voltage control scheme based on the PD algorithm, but is not limited to the PD algorithm. The PD algorithm formula is as follows:

[0046]

[0047] In the formula, k pp is the proportional coefficient of the PD control algorithm, k dd is the differential coefficient of the PD control algorithm, e V is the DC bus voltage error, that is, e V = target voltage - voltage sensor feedback voltage.

[0048] The drive motor, the drive motor control module and the voltage sensor constitute the voltage control scheme of the drive motor.

[0049] The energy management module is responsible for generating the target speed command of the generator. The specific calculation process is as follows: Figure 5 First, read the accelerator pedal opening command and the battery SOC signal. Then, according to the formula P dem = k4 × accelerator pedal opening to calculate the driver's required power, k4 is the power coefficient under acceleration conditions, which can be calculated based on the system's maximum power, but is not limited to this calculation method. Next, according to the formula P char =k5×(SOC ref-SOC) to calculate the required charging and discharging power of the battery, k5 is the battery charging and discharging power coefficient, which can be calculated based on the battery charging and discharging capacity, but is not limited to this calculation method. all =P dem +P char Calculate the total required power P according to the formula all Next, the optimal engine speed is found based on the engine efficiency MAP and the total power demand, and converted into the generator target speed. Finally, the generator target speed is output.

[0050] In the heavy-duty vehicle series hybrid power control system proposed in the present invention, a speed sensor and a voltage sensor are used to feedback the system status to the generator control module and the drive motor control module, but it is not limited to the arrangement position of the sensor and the signal transmission type. For example, the speed sensor can be integrated into the engine, the generator, placed on the mechanical structure between the engine and the generator, or there can be multiple sensors. The main purpose of the generator control module is to control it according to the speed signal.

[0051] The control method proposed in the present invention provides a lot of reference logics. The main logic is that the driver's demand directly controls the engine, and then the generator is responsible for regulating the engine and generator speeds, and the drive motor is responsible for regulating the bus voltage state to achieve power output. It is not limited to some specific details in the logic, such as the given form of some parameters.

[0052] The generator control module proposed in the present invention adopts the PD control algorithm to control the generator speed, but is not limited to the PD control algorithm, for example, a rule-based algorithm, a fuzzy algorithm, a robust algorithm, etc.

[0053] The drive motor control module proposed in the present invention adopts the PD control algorithm to control the voltage of the drive motor, but is not limited to the PD control algorithm, for example, a rule-based algorithm, a fuzzy algorithm, a robust algorithm, etc.

[0054] The energy management module proposed in the present invention provides a simple energy management method, but is not limited to this method, such as using an optimization algorithm, etc. The main purpose of this part is to improve the efficiency of the system by planning the generator speed.

[0055] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0056] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0057] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0058] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0059] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

[0060] Many other changes and modifications may be made without departing from the concept and scope of the present invention.It should be understood that the present invention is not limited to the specific embodiments, and the scope of the present invention is defined by the appended claims.

Claims

1. A heavy-duty vehicle series hybrid power control system, characterized in that: The control system includes: an engine control module, an energy management module, a generator control module and a drive motor control module; The engine control module is used to receive the accelerator pedal opening instruction, the brake pedal opening instruction and the battery SOC signal, and generate the engine throttle opening instruction after calculation and processing; The energy management module is used to receive the accelerator pedal opening instruction and the battery SOC signal, and generate the generator target speed instruction after calculation and processing according to the engine efficiency MAP map; The generator control module is used to receive the generator target speed command sent by the energy management module, collect the speed sensor feedback signal between the engine and the generator, and generate the generator torque command after calculation and processing; The drive motor control module is used to receive an accelerator pedal opening instruction, a brake pedal opening instruction and a battery SOC signal, collect a voltage sensor feedback signal on a high-voltage DC bus, and generate a drive motor torque instruction after calculation and processing.

2. A heavy-duty vehicle series hybrid power control system according to claim 1, characterized in that: The engine control module is responsible for generating an engine throttle opening instruction, and the specific method includes: First, read the accelerator pedal opening command, brake pedal opening command and battery SOC signal; then, determine whether the battery SOC is greater than the given reference SOC; if it is greater, it is considered that the battery does not need additional power supply and no throttle opening compensation is performed, that is, u com =0, otherwise it is considered that the battery needs additional power supply, then according to the formula u com =k1×(SOC ref -SOC) calculates the throttle opening compensation command, k1 is an adjustable constant coefficient, SOC ref is the reference value of the battery SOC, and further determines whether the brake pedal opening is greater than zero. If so, it is considered that the current vehicle has a braking demand, and the accelerator pedal opening command is forced to be converted to 0. Otherwise, the accelerator pedal opening command is converted into a control command u acc , according to the formula u thr =u acc +u com Calculate the engine throttle opening command u thr .

3. A heavy-duty vehicle series hybrid power control system according to claim 1, characterized in that: The energy management module is responsible for generating a target speed command for the generator, and the specific method includes: First, read the accelerator pedal opening command and battery SOC signal; then, according to the formula P dem = k4 × accelerator pedal opening to calculate the driver's required power. k4 is the power coefficient under acceleration conditions, which can be calculated based on the system's maximum power. Next, according to the formula P char =k5×(SOC ref -SOC) calculates the required charging and discharging power of the battery, k5 is the battery charging and discharging power coefficient, which can be calculated based on the battery charging and discharging capacity. The next step is P all =P dem +P char Calculate the total required power P according to the formula all ; Next, find the optimal operating speed of the engine according to the engine efficiency MAP diagram and the total required power, and convert it into the generator target speed; finally, output the generator target speed.

4. A heavy-duty vehicle series hybrid power control system according to claim 1, characterized in that: The generator control module is responsible for generating a generator torque command to control the generator and engine speed; the specific method includes: First, read the generator target speed command and speed sensor signal sent by the energy management module, then determine whether the generator speed is greater than the target speed. If so, execute the generator speed control algorithm to generate the generator torque command u gm ; Otherwise, the generator torque command is set to 0, that is, u gm =0; Finally, the generator torque command u is output gm ; The generator speed control scheme is formed by the generator, the generator control module and the speed sensor.

5. A heavy-duty vehicle series hybrid power control system according to claim 4, characterized in that: The generator speed control algorithm adopts the PD algorithm, and the specific formula is as follows: In the formula, k p is the proportional coefficient of the PD control algorithm, k d is the differential coefficient of the PD control algorithm, e ω is the generator speed error, that is, e ω =Target speed - engine speed.

6. A heavy-duty vehicle series hybrid power control system according to claim 1, characterized in that: The drive motor control module is responsible for generating a drive motor torque instruction, and the specific method includes: First, the accelerator pedal opening command, brake pedal opening command, battery SOC signal and voltage sensor signal are read; next, the drive motor torque constraint is calculated according to the accelerator pedal opening and brake pedal opening. The torque upper limit constraint is calculated according to T max = k2 × accelerator pedal opening, k2 is a constant coefficient greater than 0; the torque lower limit constraint is calculated according to T min = k3 × brake pedal opening calculation, k3 is a constant coefficient less than 0; the next step is to determine whether the brake pedal opening is greater than zero. If it is greater, then further determine whether the battery SOC is greater than the reference SOC ref Otherwise, determine whether the bus voltage is greater than the target bus voltage; if the battery SOC is greater than the reference SOC ref , the drive motor torque command u dm Set to 0 and proceed to the next step, otherwise follow the formula u dm = k4 × battery charging current upper limit to calculate the drive motor torque command u dm , k4 is a constant coefficient less than 0, further judging u dm >T min Is it true? If not, u dm Set to T min , otherwise go to the next step; if the bus voltage is greater than the target bus voltage, it does not hold, and the motor torque command u is driven dm Set to 0 and go to the next step, otherwise execute the drive motor control algorithm to generate the drive motor torque command u dm , further determine u dm >T min Is it true? If true, u dm Set to T max Otherwise, go directly to the next step; further, output the final drive motor rotation instruction u dm ; The voltage control scheme of the drive motor is formed by the drive motor, the drive motor control module and the voltage sensor.

7. A heavy-duty vehicle series hybrid power control system according to claim 6, characterized in that: The drive motor control algorithm adopts the PD control algorithm; the PD algorithm formula is as follows: In the formula, k pp is the proportional coefficient of the PD control algorithm, k dd is the differential coefficient of the PD control algorithm, e V is the DC bus voltage error, that is, e V = target voltage - voltage sensor feedback voltage.

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