Ultralow-temperature power generation control method and system for extended-range vehicle

Abstract

The invention relates to the technical field of vehicle control, and provides an ultralow-temperature power generation control method and system for an extended-range vehicle. Comprising the following steps: acquiring a driving power consumption predicted value, an accessory power consumption predicted value and a battery discharge power predicted value under the condition that the temperature of a power battery cell is lower than a preset temperature threshold value; performing a feedforward operation based on the driving power consumption prediction value, the accessory power consumption prediction value, and the battery discharge power prediction value to generate a first generator torque; the actual consumed power and the actual generated power of the vehicle are obtained; pID operation is carried out based on the difference value between the actual consumed power and the actual generated power, and a second generator torque is generated; superposing the first generator torque and the second generator torque to generate a generator target torque; and controlling the generator to execute the generator target torque. The generated power and the consumed power are dynamically balanced, and the rapid maneuvering capability of the vehicle under the ultralow temperature condition is achieved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to an ultra-low temperature power generation control method and system for an extended-range vehicle. Background Art

[0002] In ultra-low temperature environments, vehicle maneuverability (the ability of a vehicle to effectively exert its maneuverability to achieve fast and flexible movement) is an important performance characteristic. For special off-road vehicles, considering their special working scenarios, the vehicle's maneuverability needs to be met at a minimum of -43±3°C. In this environment, traditional internal combustion engine-driven special off-road vehicles generally use an on-board boiler system to assist in heating the engine coolant. When the system is heated to a temperature that allows the vehicle to maneuver, the vehicle is started and begins to drive. However, the problem is that the heating process of the on-board boiler system takes a long time, which is not conducive to the rapid maneuverability of the vehicle.

[0003] With the development of vehicle technology, for special off-road vehicles that adopt the extended-range technology architecture, since they are equipped with power batteries and directly connected high-voltage generators, and the power batteries using carbon nanotube technology, they still have a certain discharge capacity under ultra-low temperature conditions, and comprehensively meet the conditions for ultra-low temperature and high-voltage starting. However, the problem is that although the vehicle's range-extending system can be successfully started, it still cannot have the ability to drive continuously, that is, there is still a problem of insufficient maneuverability. The reason is that due to the low ambient temperature, the power battery only has the ability to discharge but not to charge. Therefore, the high-voltage system loses the ability to charge buffer. In this case, the range extender's power generation will be directly used for load consumption, requiring the power generation power to be equal to the power consumption power in real time. Otherwise, too much or too little power generation will cause the high-voltage system to be overcharged and over-discharged, further damaging the high-voltage system. The range extender of the extended-range vehicle generates electricity to drive the motor, accessories and other components for power consumption. Since the range extender system relies on the engine to provide energy for power generation, and the working response characteristics of the engine power generation are different from those of the power-consuming components, the engine responds slowly while the power-consuming components respond quickly. Therefore, in the dynamic process, inconsistencies in power generation and power consumption are prone to occur, especially under conditions where the system operating conditions change rapidly, such as rapid loading, rapid load dumping and other conditions. On the other hand, the power generated by the range extender is generated according to the real-time feedback of the system power consumption. The process is to consume first, and then respond to the power generation demand at a certain rate according to the power consumption. The intermediate power difference is supplemented by the discharge of the power battery. The algorithm has advantages in the system's NVH characteristics and overcharge and over-discharge protection, but the algorithm also has asynchrony in control time.

[0004] Therefore, the above combined factors make it difficult for the range-extended systems of existing vehicles to maintain equal and synchronous control of power generation and consumption in real time when the power battery has no charging capability, further limiting the maneuverability of the vehicle. Summary of the invention

[0005] In view of this, an ultra-low temperature power generation control method and system for a range-extended vehicle are provided in an embodiment of the present application to solve the problem that the range-extended system of an existing vehicle cannot maintain real-time equal-synchronous control of power generation and power consumption under the condition that the power battery has no charging ability, and thus cannot achieve the fast maneuverability of the vehicle under ultra-low temperature conditions.

[0006] A first aspect of an embodiment of the present application provides an ultra-low temperature power generation control method for a range-extended vehicle, including:

[0007] When the temperature of the power battery cell is lower than a preset temperature threshold, obtaining a predicted value of driving power consumption, a predicted value of accessory power consumption, and a predicted value of battery discharge power;

[0008] Performing a feedforward operation based on the predicted value of driving power consumption, the predicted value of accessory power consumption, and the predicted value of battery discharge power to generate a first generator torque;

[0009] Obtaining the actual power consumption and the actual power generation of the vehicle;

[0010] Performing a PID operation based on the difference between the actual power consumption and the actual power generation to generate a second generator torque;

[0011] Superposing the first generator torque and the second generator torque to generate a target generator torque;

[0012] Controlling the generator to execute the target generator torque.

[0013] A second aspect of an embodiment of the present application provides an ultra-low temperature power generation control system for a range-extended vehicle, including:

[0014] Including a power domain control module, a generator control module, an engine control module, a power battery control module, and a power distribution control module;

[0015] The generator control module is connected to the generator, the engine control module is connected to the engine, the power distribution control module is connected to the power distribution box, the power battery control module is connected to the power battery, the power distribution box is connected to the generator, the power battery, and the load through hard wires, and the power domain controller is connected to the engine control module, the generator control module, the power distribution box control module, and the drive control module through a network cable;

[0016] The power domain control module is configured to send a predicted value of driving power consumption to the generator control module;

[0017] The generator control module is configured to:

[0018] When the temperature of the power battery cell is lower than the preset temperature threshold, obtain the predicted value of the driving power consumption, the predicted value of the accessory power consumption, and the predicted value of the battery discharge power;

[0019] Perform a feed-forward operation based on the predicted value of the driving power consumption, the predicted value of the accessory power consumption, and the predicted value of the battery discharge power to generate the first generator torque;

[0020] Obtain the actual power consumption and the actual power generation of the vehicle;

[0021] Perform a PID operation based on the difference between the actual power consumption and the actual power generation to generate the second generator torque;

[0022] Superimpose the first generator torque and the second generator torque to generate the target generator torque;

[0023] Control the generator to execute the target generator torque.

[0024] The third aspect of the embodiments of the present application provides an electronic device, including a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the electronic device implements the ultra-low temperature power generation control method of the range extender vehicle provided in the first aspect of the embodiments of the present application.

[0025] The fourth aspect of the embodiments of the present application provides a computer program product, including a computer program. When the computer program is run, the method described in the first aspect of the embodiments of the present application is executed.

[0026] The ultra-low temperature power generation control method for a range-extended vehicle provided in the first aspect of the embodiments of the present application obtains a predicted value of driving power consumption, a predicted value of accessory power consumption, and a predicted value of battery discharge power when the temperature of the power battery cells is lower than a preset temperature threshold; performs a feedforward operation based on the predicted value of driving power consumption, the predicted value of accessory power consumption, and the predicted value of battery discharge power to generate a first generator torque; obtains the actual power consumption and the actual power generation of the vehicle; performs a PID operation based on the difference between the actual power consumption and the actual power generation to generate a second generator torque; superimposes the first generator torque and the second generator torque to generate a target generator torque; and controls the generator to execute the target generator torque. By adopting torque superposition control of feedforward operation (based on driving / accessory / battery power prediction) and PID operation (based on actual power difference), compared with the traditional single control method which is difficult to balance the dynamic response speed and steady-state accuracy, resulting in power generation lag or overshoot, this method combines feedforward operation with PID closed-loop control to actively predict and compensate for power demand differences in ultra-low temperature conditions. The feedforward module quickly generates a reference torque based on multi-source power prediction values, and the PID module corrects the actual power deviation in real time. The two are directly superimposed in the torque domain, which not only ensures the fast response ability of the power generation system in low temperature environments but also suppresses the steady-state error through closed-loop regulation, solves the problems of dynamic response lag and power mismatch of traditional control methods under cold start conditions, realizes the dynamic balance between power generation power and power consumption, and further realizes the fast maneuverability of the vehicle under ultra-low temperature conditions.

[0027] It can be understood that the beneficial effects of the second to fourth aspects above can be referred to the relevant descriptions in the first aspect above, and will not be elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0029] Figure 1 It is a schematic flowchart of an ultra-low temperature power generation control method for a range-extended vehicle provided by an embodiment of the present application;

[0030] Figure 2 It is a schematic flowchart of an ultra-low temperature power generation control method for a range-extended vehicle provided by another embodiment of the present application;

[0031] Figure 3 It is a schematic flowchart of an ultra-low temperature power generation control method for a range-extended vehicle provided by another embodiment of the present application;

[0032] Figure 4 is a schematic flow chart of a super-low temperature power generation control method for a range-extended vehicle provided by another embodiment of the present application;

[0033] Figure 5 is a schematic flow chart of a super-low temperature power generation control method for a range-extended vehicle provided by another embodiment of the present application;

[0034] Figure 6 is a schematic structural diagram of a super-low temperature power generation control system for a range-extended vehicle provided by an embodiment of the present application. Detailed implementation manners

[0035] In the following description, for the purpose of illustration rather than limitation, specific details such as specific system architectures, technologies, etc. are set forth in order to provide a thorough understanding of the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary details.

[0036] It should be understood that when used in the specification and appended claims of the present application, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0037] It should also be understood that the term "and / or" as used in the specification and appended claims of the present application refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0038] In addition, in the description of the specification and appended claims of the present application, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0039] The reference to "one embodiment" or "some embodiments" or the like described in the specification of the present application means that a specific feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, the phrases "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in another way. The terms "including", "comprising", "having", and their variants all mean "including but not limited to", unless otherwise specifically emphasized in another way.

[0040] As Figure 1 shown, in one embodiment, the ultra-low temperature power generation control method for an extended-range vehicle provided by the embodiments of the present application includes the following steps S101 to S106:

[0041] Step S101: When the temperature of the power battery cell is lower than the preset temperature threshold, obtain the predicted value of the driving power consumption, the predicted value of the accessory power consumption, and the predicted value of the battery discharge power.

[0042] In application, at the same time, the generator control module also obtains the battery discharge power.

[0043] Step S102: Perform a feed-forward operation based on the predicted value of the driving power consumption, the predicted value of the accessory power consumption, and the predicted value of the battery discharge power to generate the first generator torque.

[0044] Step S103: Obtain the actual power consumption and the actual power generation of the vehicle.

[0045] Step S104: Perform a PID operation based on the difference between the actual power consumption and the actual power generation to generate the second generator torque.

[0046] Step S105: Superimpose the first generator torque and the second generator torque to generate the generator target torque.

[0047] Step S106: Control the generator to execute the generator target torque.

[0048] In application, in the typical application of a special off-road vehicle, it is necessary to adapt to the temperature condition of -43 ± 3°C, which is generally significantly lower than the temperature threshold at which the power battery allows charging. When the temperature of the power battery cell is lower than the lowest temperature at which the power battery allows charging, the power battery cannot be charged, and at this time, it is determined that the vehicle is in an ultra-low temperature state. In the embodiments of the present application, the preset temperature threshold is preset to be slightly higher than the lowest temperature at which the power battery allows charging, for example, -30°C (only for example, it can also be other temperatures). In step S101, if the obtained temperature of the power battery cell is lower than the preset temperature threshold, it is determined that the vehicle is in an ultra-low temperature state.

[0049] In the application, under the ultra-low temperature condition of (-43±3°C), considering the requirements of the power generation and consumption processes to be executed synchronously and equally, power generation and power consumption instructions are sent synchronously according to the requirements. For the distributed control scheme, the same bus communication cycle is generally used for control; for the integrated control scheme, synchronization is achieved through global variables inside the embedded system software. At the same time, a time synchronization correction module is set up to enable the system to have the ability to adjust for synchronization. This method can be executed in cooperation with the in-vehicle Power Domain Controller (PDC) and the Generator Control Unit (GCU). The in-vehicle Power Domain Controller can communicate with subsystems such as the Generator Control Unit and the Battery Management System (BMS) through the Controller Area Network (CAN) bus.

[0050] In the application, under the ultra-low temperature condition of (-43±3°C), the power domain control module sends the predicted value of the driving consumption power and the accessory consumption power to the generator control module, and takes the predicted value of the driving consumption power + the accessory consumption power as the basic expected power generation amount (i.e., the feedforward amount of the power generation power). The generator control module adopts a control configuration of "feedforward based on the system's expected power generation + PID based on the real-time power generation and consumption difference". Among them, the feedforward control based on the system's expected power generation solves the advance control of the system's main power generation power, and at the same time, the feedforward control has the function of reducing the static error of the system control and improving the control quality; the PID part based on the real-time power generation and consumption difference is used to eliminate the real-time power generation and consumption difference. It should be noted that the power limit algorithm of the aforementioned power domain control module can be used to eliminate the over-discharge problem of the high-voltage system, and the feedforward based on the system's expected power generation + the PID control algorithm based on the power generation and consumption difference can be used to eliminate the overcharge problem under conditions such as load shedding.

[0051] In the embodiment of the present application, the generator control module receives the system expected power generation amount signal calculated by the power domain control module. The engine control module uses a control mode based on the feedforward part of the system expected power generation amount + the PID part based on the power generation error to achieve the advance control of the power generation process, enabling the system to have the ability of synchronous and equal control of power generation and power consumption. At the same time, a super high-voltage and super low-voltage protection control module under ultra-low temperature conditions is set to ensure the system protection function under abnormal conditions. By combining the feedforward operation with the PID closed-loop control, the power demand difference is actively predicted and compensated under ultra-low temperature conditions. The feedforward module quickly generates a reference torque based on the multi-source power prediction value, and the PID module corrects the actual power deviation in real time. The two are directly superimposed in the torque domain, which not only ensures the fast response ability of the power generation system under low temperature environment, but also suppresses the steady-state error through closed-loop regulation, solves the problems of dynamic response lag and power mismatch of traditional control methods under cold start conditions, and realizes the dynamic balance of power generation power and consumption power.

[0052] In one embodiment, as Figure 2 shown, it further includes:

[0053] Step S201: Obtain the driver's required torque, battery discharge power, accessory consumption power, and generator power generation power.

[0054] Step S202: Calculate the drive power limit value, where the drive power limit value = battery discharge power + generator power generation power - accessory consumption power.

[0055] Step S203: Use the drive power limit value to constrain the driver's required torque to obtain the constrained drive power.

[0056] Step S204: Convert the constrained drive power into a drive torque based on the vehicle speed.

[0057] Step S205: Control the drive motor to execute the drive torque;

[0058] Step S206: Perform power conversion on the drive torque based on the real-time speed of the drive motor to obtain a predicted value of the drive consumption power.

[0059] In the application, as Figure 3 shown, under ultra-low temperature (-43±3°C) conditions, the power domain control module directly receives the driver's throttle pedal opening signal. After the throttle signal verification, it further queries the throttle torque characteristic table in combination with the vehicle speed to output the initial driver's required torque. At the same time, the power domain control module limits the drive power according to the power supply capacity of the power pack at the current moment, aiming to ensure that at any moment, the system drive consumption power is less than or equal to the drive energy supply capacity of the power pack, that is, there is no problem of over-discharge of the power battery.

[0060] In an application, the driving torque is limited to the sum of the instantaneous discharge power of the power battery at the current moment (i.e., the battery discharge power) and the real-time power generation power of the range extender at the current moment (i.e., the generator power generation power). Further, the power consumption of vehicle accessories is removed to obtain the driving power limit value. Then, based on the vehicle speed, the constrained driving power is converted into a driving torque. Among them, since the battery discharge power, the generator power generation power, and the accessory power consumption are all real-time data, the driving power limit value is not a fixed value but dynamically changes according to the real-time data. After the driver's required torque is constrained by this driving torque, if the driver's required torque is not greater than the driving torque obtained by converting the constrained driving power, the driver's required torque is used as the driving torque that the driving motor needs to execute. If the driver's required torque is greater than the driving torque obtained by converting the constrained driving power, the driver's required torque is limited to the driving torque obtained by converting the constrained driving power, and the driving motor executes this driving torque.

[0061] In an application, the generator power generation power is determined by calculating the real-time output current and voltage of the generator; the battery discharge power is calculated by the power battery module and sent in real time; the accessory power consumption is obtained by calculating the power consumed by each accessory in real time.

[0062] In an application, in addition to controlling the driving motor to execute the driving torque, the power domain control module also converts the driving torque combined with the actual rotational speed of the driving motor into a predicted value of the driving power consumption, which is used to be sent to the generator control module for feedforward operation.

[0063] In the embodiment of the present application, by dynamically calculating the driving power limit value and using it as a constraint condition for the driver's required torque, a direct association between the power supply capacity and the driving demand is constructed at the energy distribution level, enabling the driving torque decision to always be within the power supply range, fundamentally preventing the risk of over-discharge of the battery, and achieving real-time balance between energy supply and consumption.

[0064] In one embodiment, obtaining the actual power consumption and actual power generation of the vehicle includes:

[0065] Step S301: Obtain the real-time voltage and current data of the generator, and calculate the generator power generation power.

[0066] Step S302: Obtain the voltage and current data after the driving motor executes the driving torque, and calculate the driving power consumption.

[0067] Step S303: Obtain the accessory voltage and current data, and calculate the accessory power consumption.

[0068] Step S304: Take the sum of the driving power consumption and the accessory power consumption as the actual power consumption, and take the generator power generation power as the actual power generation power.

[0069] In the application, the feedforward operation and the PID operation are integrated into one operation module. Among them, the inputs of the feedforward operation part include:

[0070] a) The predicted value of the driving power consumption output by the power domain control module, which is used to characterize the expected power consumption of the driving part;

[0071] b) The accessory power consumption at the previous moment calculated by the control system, which is used to predict the accessory power consumption at the next moment;

[0072] c) The power of the power battery discharged at the previous moment received by the control system, which is used to predict the power of the power battery discharged at the next moment. The purpose of this part is to eliminate the discharging process of the power battery and serve as a correction term for the overall feedforward part.

[0073] Combining the above powers and the actual generator speed, the predicted power generation is converted into the first generator torque. In addition, the powers of the above three parts are all predicted values and are calculated based on the working principle of the system, meeting the conditions for feedforward in the time domain of the control system.

[0074] In the application, the input of the PID operation part is the difference between the actual power consumption of the vehicle and the actual power generation, and the difference between the sum of the driving power consumption and the accessory power consumption and the power generation of the generator. Taking this difference as the input of the PID operation, with the goal of eliminating the difference between the power generation and power consumption, the PID outputs the second generator torque. The first generator torque and the second generator torque are superimposed to generate the initial generator target torque. The initial generator target torque is input to the high and low bus voltage limit module.

[0075] In the embodiment of the present application, by respectively collecting the real-time electrical parameters of each subsystem (driving motor, generator, battery, accessory) and calculating the actual power values, a multi-node closed-loop power verification mechanism is constructed, eliminating the model simplification error of traditional theoretical estimation, providing a high-precision data benchmark for feedforward prediction and PID adjustment, and improving the credibility of the control system from the source.

[0076] In one embodiment, as Figure 4 shown, step S105 includes:

[0077] Step S1051: Superimpose the first generator torque and the second generator torque to generate the initial generator target torque.

[0078] Step S1052: Calculate the generator torque limit based on the DC bus voltage limit.

[0079] Step S1053: Use the generator torque limit to constrain the initial generator target torque to obtain the generator target torque.

[0080] In the application, considering that the system may still have problems of exceeding the bus high-voltage limit and falling below the bus low-voltage limit under abnormal conditions such as inaccurate power consumption calculation, the module further designs high- and low-voltage limit modules to further limit the aforementioned power generation torque based on the system's expected power generation feedforward + PID calculation based on the difference between power generation and power consumption.

[0081] In the embodiment of the present application, by combining the initial torque after superimposing the feedforward and PID with the dynamic constraint based on the bus voltage limit, voltage safety boundary control is introduced in the torque generation stage, so that the torque output is always within the tolerance range of the electrical system, which not only retains the dynamic performance of the composite control, but also prevents overvoltage / undervoltage risks through the voltage feedback limiting mechanism, and solves the conflict problem between electrical protection and power regulation under high dynamic load changes.

[0082] In one embodiment, based on the DC bus voltage limit, calculating the generator torque limit includes:

[0083] Using the difference between the target bus high-voltage limit and the measured bus voltage value as the input, performing PID calculation to generate the upper limit value of the generator torque;

[0084] Using the difference between the target bus low-voltage limit and the measured bus voltage value as the input, performing PID calculation to generate the lower limit value of the generator torque.

[0085] In the application, the measured bus voltage value is a real-time measured value, such as Figure 5 shown, the module sets two types of limits for high- and low-voltage overlimits respectively, and the specific algorithm is as follows:

[0086] a) High-voltage limit: Design two-stage high-voltage protection. The first stage: Using the difference between the target bus high-voltage limit and the measured bus voltage value as the input, performing PID calculation to calculate and output the dynamic upper limit of the power generation torque to prevent system overcharge under abnormal conditions. The specific high-voltage limit setting is lower than the level that the system components can withstand, as a more priority protection measure for the system; The second stage: If the first-stage limit is broken through and it cannot be adjusted within a certain time, that is, the measured bus voltage value obtained in real time still exceeds the target bus voltage limit, the power generation power will be forcibly unloaded, that is, the power generation torque will be forcibly controlled to 0, and at the same time, the engine will be controlled to perform fuel cut-off protection control; The threshold is set according to the system tolerance. When the system power generation breaks through the first-stage high-voltage protection of the generator control module, the control system will cooperate with the generator to synchronously perform system unloading protection. Specifically, the emergency system protection control is carried out by cutting off the engine fuel injection, which is used in conjunction with the second-stage protection of the generator control ultra-high voltage.

[0087] b) Low - voltage limit: Using the difference between the low - voltage limit of the target bus and the current bus voltage as the input, perform PID calculation, and calculate the dynamic lower limit of the generating torque output to prevent over - discharge of the system in abnormal situations; similar to the high - voltage limit setting, for the specific low - voltage limit setting, it is higher than the level that the system components can withstand as a more prioritized protection measure for the system.

[0088] In the embodiments of the present application, by setting independent PID control channels for high - voltage and low - voltage thresholds respectively, a differential response strategy for voltage fluctuation direction is realized. The PID on the high - voltage side accurately calculates the upper limit of torque when suppressing voltage overshoot, and the PID on the low - voltage side intelligently increases the lower limit of torque when compensating for voltage drop. The two - way adjustment mechanism overcomes the response hysteresis defect of the traditional single - threshold amplitude limiting, making the voltage stable control more forward - looking.

[0089] In one embodiment, using the generator torque limit to constrain the initial generator target torque to obtain the generator target torque, including:

[0090] When the initial generator target torque does not exceed the generator torque limit, use the initial generator target torque as the generator target torque;

[0091] When the initial generator target torque exceeds the generator torque limit, output the generator torque limit as the generator target torque.

[0092] In the embodiments of the present application, by establishing a direct comparison logic between the initial torque and the limit range, and using a hard - constraint rule to forcibly correct the out - of - bound torque, a rigid safety boundary for torque output is constructed at the algorithm level. It not only retains the dynamic adjustment ability of the composite control strategy but also eliminates the overload risk through the boundary protection mechanism, achieving the optimal balance between control freedom and system safety.

[0093] In one embodiment, after controlling the generator to execute the generator target torque, including:

[0094] If the measured value of the bus voltage still exceeds the target bus voltage limit, control the torque of the generator to 0.

[0095] In application, after the generator executes the generator target torque, if within a preset time duration, the measured value of the bus voltage still cannot be within the target bus voltage limit, control the torque of the generator to 0, that is, unload and stop the generator.

[0096] In the embodiments of the present application, by introducing an over - limit zero - return protection mechanism after torque execution, a whole - process monitoring system from instruction generation to actual output is constructed. When it is detected that the executed torque abnormally exceeds the limit, the power output is immediately cut off. The posterior - correction makes up for the inherent error accumulation defects of feed - forward prediction and closed - loop regulation, significantly improving the system fault - tolerance ability.

[0097] In one embodiment, it further includes:

[0098] Step S401: Obtain the engine coolant temperature;

[0099] Step S402: When the engine coolant temperature is lower than the preset temperature threshold, control the engine to enter a constant speed operation mode;

[0100] Wherein, in the constant speed operation mode, the engine speed is positively correlated with the engine coolant temperature, and the speed does not change with the change of the power generation power.

[0101] In application, under the ultra-low temperature condition of -43 ± 3°C, the system is set to the engine constant speed power generation mode (the engine generates power at a relatively fixed target speed), and the generator controls the power generation torque according to the power consumption demand of the system. Among them, in the engine constant speed control, the speed does not change with the change of the power generation power, but it can be slowly adjusted according to the engine coolant temperature. Under relatively low engine coolant temperature conditions, a lower engine speed is adopted to reduce the wear of the engine under low temperature conditions and improve the engine life and reliability; as the coolant temperature rises, the engine speed is gradually increased to provide greater power generation capacity. The specific relationship between the engine speed and its coolant temperature is calibrated according to the specific engine characteristics.

[0102] In application, the engine control module receives the mode instruction of the power domain control module and operates at a relatively fixed engine speed under ultra-low temperature conditions to reduce the difficulty of power generation quality control. On the other hand, the engine can slowly adjust the engine speed according to the engine coolant temperature. Under low coolant temperature conditions, a lower engine speed is adopted to reduce the wear of the engine, extend the service life and improve the reliability; as the coolant temperature rises, the engine speed is gradually increased to provide greater power generation capacity. The specific relationship between the coolant temperature and the engine speed is set according to the specific engine system capabilities.

[0103] In the embodiment of the present application, by establishing a positive correlation mapping relationship between the engine speed and the coolant temperature and locking the speed value, the optimal thermal efficiency range of the engine is actively maintained under low temperature working conditions, avoiding the speed fluctuation caused by the traditional power following strategy, ensuring the power supply stability of the power generation system, and reducing mechanical wear through the constant speed operation mode.

[0104] In one embodiment, under ultra-low temperature conditions, the warm air PTC is enabled through the power distribution control module as a power consumption buffer for the high-voltage system, alleviating the overcharge problem caused by excessive power generation power to a certain extent and improving the robustness of the system.

[0105] Through the above comprehensive control, the vehicle realizes the maneuverability of starting and driving immediately under the ultra-low temperature condition of -43 ± 3°C.

[0106] It should be understood that the sequence numbers of the steps in the above embodiments do not indicate the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0107] In one embodiment, under the condition of -43±3°C, the vehicle is completely cold-soaked in the natural environment, and the vehicle starts the high-voltage of the range extender system through the power battery and the generator. The driver drives the vehicle through the accelerator, and the control system performs power generation control according to the comprehensive control scheme. During the dynamic process, the power generation power is kept consistent with the consumption power in real time to avoid the problems of overcharging and over-discharging of the system, so as to achieve rapid maneuverability after the vehicle starts.

[0108] In one embodiment, under the condition of -43±3°C, the driver drives the vehicle to perform sudden acceleration and sudden deceleration operations on the accelerator. Under the condition of sudden acceleration of the accelerator, the power domain control module calculates the drive power limit of the system to ensure that the system does not have the problem of over-discharging of the power battery due to the instantaneous drive power demand being greater than the power supply capacity of the power pack; under the condition of sudden deceleration of the accelerator, the system is in a load rejection condition, and the range extender system reduces the power generation power in advance according to the expected load drop to avoid the problem of high-voltage overcharging caused by the slow load rejection of the range extender generator.

[0109] In one embodiment, under the condition of -43±3°C, due to abnormal conditions of the vehicle, the calculated accessory consumption power is inaccurate, resulting in inaccurate power generation power of the range extender, further causing overcharging and over-discharging problems, corresponding to the phenomena of bus voltage increase and decrease. The generator control unit monitors the bus voltage and sets dynamic high-voltage and low-voltage power generation torque limits to limit the power generation power of the range extender and control the impact of overcharging and over-discharging of the system after the power generation power is inaccurate; further, if the above-mentioned limits still cannot effectively control the overcharging and over-discharging problems, the system sets a final protection link, that is, generator unloading and engine fuel cut-off control, to protect the high-voltage system in more extreme cases.

[0110] As Figure 6 shown, a super-low temperature power generation control system for a range-extended vehicle provided by the present application includes a power domain control module, a generator control module, an engine control module, a power battery control module, and a power distribution control module;

[0111] The generator control module is connected to the generator, the engine control module is connected to the engine, the power distribution control module is connected to the power distribution box, the power battery control module is connected to the power battery, the power distribution box is connected to the generator, the power battery, and the load through hard wires, and the power domain controller is connected to the engine control module, the generator control module, the power distribution box control module, and the drive control module through a network cable;

[0112] The power domain control module is used to send the predicted value of the driving power consumption to the generator control module;

[0113] The generator control module is used to:

[0114] When the temperature of the power battery cell is lower than the preset temperature threshold, obtain the predicted value of the driving power consumption, the predicted value of the accessory power consumption, and the predicted value of the battery discharge power;

[0115] Perform a feedforward operation based on the predicted value of the driving power consumption, the predicted value of the accessory power consumption, and the predicted value of the battery discharge power to generate the first generator torque;

[0116] Obtain the actual power consumption and the actual power generation of the vehicle;

[0117] Perform a PID operation based on the difference between the actual power consumption and the actual power generation to generate the second generator torque;

[0118] Superimpose the first generator torque and the second generator torque to generate the target generator torque;

[0119] Control the generator to execute the target generator torque.

[0120] In the application, the feedforward operation and the PID operation are integrated into an operation module, and this operation module is a functional module within the generator control module.

[0121] In the embodiment of the present application, the power domain controller is used as the central decision-making unit through a modular architecture, and forms a hierarchical control network with the generator control module, the power distribution control module, etc. This not only ensures the fast transmission of key control instructions (hard wire direct connection), but also realizes global data sharing through the network cable, providing a highly reliable hardware support platform for the implementation of the composite control strategy.

[0122] In one embodiment, the power domain control module is further used to:

[0123] Obtain the driver's demand torque, the battery discharge power, the accessory power consumption, and the generator power generation;

[0124] Calculate the driving power limit, and the driving power limit = battery discharge power + generator power generation - accessory power consumption;

[0125] Use the driving power limit to constrain the driver's demand torque to obtain the constrained driving power;

[0126] Convert the constrained driving power into a driving torque based on the vehicle speed;

[0127] Control the drive motor to execute the driving torque;

[0128] The driving torque is converted into power based on the real-time speed of the driving motor to obtain the predicted value of the driving power consumption.

[0129] The embodiment of the present application integrates the driving demand analysis and power supply capacity assessment functions in the power domain controller, puts the energy constraint in front of the driving torque generation stage, and realizes the closed-loop optimization of "demand decision-making-energy supply". It not only retains the complete transmission of the driver's intention, but also improves the energy utilization rate to the theoretical limit, forming a deep coordination mechanism of human-vehicle-energy efficiency.

[0130] In application, each module in the ultra-low temperature power generation control device of the extended-range vehicle can be a software program module, or can be implemented by different logic circuits integrated in the processor, or can be implemented by multiple distributed processors.

[0131] An embodiment of the present application also provides an electronic device, including: at least one processor, a memory, and a computer program stored in the memory and executable on at least one processor, wherein the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0132] In applications, the electronic device may include, but is not limited to, a processor and a memory.

[0133] In applications, the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0134] In an application, the memory may be an internal storage unit of an electronic device in some embodiments, such as a hard disk or memory of the electronic device. The memory may also be an external storage device of the electronic device in other embodiments. For example, a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc., equipped on the electronic device. Further, the memory may also include both an internal storage unit and an external storage device of the electronic device. The memory is used to store an operating system, application programs, a BootLoader, data, and other programs, such as program codes of computer programs. The memory may also be used to temporarily store data that has been output or will be output.

[0135] It should be noted that for the content such as information interaction and execution process between the above-mentioned devices / units, since it is based on the same concept as the method embodiments of the present application, for its specific functions and the technical effects brought, reference can be specifically made to the method embodiment part, and details are not described herein again.

[0136] Those skilled in the art can clearly understand that for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is used as an example. In actual applications, the above functions can be allocated to different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated into a processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit. In addition, the specific names of each functional unit and module are only for the convenience of mutual distinction and do not limit the protection scope of the present application. The specific working process of the units and modules in the above system can refer to the corresponding process in the foregoing method embodiments, and details are not described herein again.

[0137] The embodiments of the present application also provide a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in the above-mentioned method embodiments can be implemented.

[0138] The embodiments of the present application provide a computer program product, including a computer program. When the computer program product runs on an electronic device, the electronic device can implement the steps in the above-mentioned method embodiments when executed.

[0139] When an integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, to implement all or part of the processes in the above method embodiments of this application, a computer program can be used to instruct the relevant hardware to complete. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc. The computer-readable medium can at least include: any entity or device that can carry the computer program code to the device / electronic device, recording medium, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal, and software distribution medium. For example, a USB flash drive, a mobile hard disk, a magnetic disk, or an optical disc, etc. In some jurisdictions, according to legislation and patent practice, the computer-readable medium cannot be an electrical carrier signal and a telecommunication signal.

[0140] In the above embodiments, the descriptions of the respective embodiments have their own focuses. For the parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0141] Those of ordinary skill in the art can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of this application.

[0142] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of the devices or units can be in an electrical, mechanical or other form.

[0143] The unit described as a separation component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in one place or may be distributed across multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0144] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for controlling ultra-low temperature power generation of an extended-range vehicle, characterized in that: include: When the temperature of the power battery cell is lower than a preset temperature threshold, a driving power consumption prediction value, an accessory power consumption prediction value and a battery discharge power prediction value are obtained; Performing a feedforward operation based on the driving power consumption prediction value, the accessory power consumption prediction value and the battery discharge power prediction value to generate a first generator torque; Obtain the actual power consumption and actual power generation of the vehicle; Performing a PID operation based on the difference between the actual power consumption and the actual power generation to generate a second generator torque; superimposing the first generator torque and the second generator torque to generate a generator target torque; The generator is controlled to execute the generator target torque.

2. The ultra-low temperature power generation control method for an extended range vehicle according to claim 1, characterized in that: The step of superimposing the first generator torque and the second generator torque to generate a generator target torque includes: superimposing the first generator torque and the second generator torque to generate an initial generator target torque; Calculate the generator torque limit based on the DC bus voltage limit; The generator torque limit is used to constrain the initial generator target torque to obtain the generator target torque.

3. The ultra-low temperature power generation control method for an extended range vehicle according to claim 2, characterized in that: The step of calculating the generator torque limit value based on the DC bus voltage limit value includes: The difference between the target bus high voltage limit and the bus voltage measurement value is used as input to perform PID calculation and generate the generator torque upper limit value; The difference between the target bus low voltage limit and the bus voltage measurement value is used as input to perform PID calculation and generate the generator torque lower limit.

4. The ultra-low temperature power generation control method for an extended-range vehicle according to claim 3, characterized in that: The using the generator torque limit value to constrain the initial generator target torque to obtain the generator target torque includes: When the initial generator target torque does not exceed the generator torque limit, using the initial generator target torque as the generator target torque; When the initial generator target torque exceeds the generator torque limit value, the generator torque limit value is output as the generator target torque.

5. The ultra-low temperature power generation control method for an extended range vehicle according to claim 4, characterized in that: After the generator is controlled to execute the generator target torque, the method includes: If the bus voltage measurement value still exceeds the target bus voltage limit value, the torque of the generator is controlled to be 0.

6. The ultra-low temperature power generation control method for an extended range vehicle according to claim 1, characterized in that: Also includes: Get engine coolant temperature; When the engine coolant temperature is lower than a preset temperature threshold, controlling the engine to enter a constant speed operation mode; Wherein, in the constant speed working mode, the speed of the engine is positively correlated with the engine coolant temperature, and the speed does not change with the change of the generated power.

7. The ultra-low temperature power generation control method for an extended range vehicle according to claim 1, characterized in that: Also includes: Obtain driver demand torque, battery discharge power, accessory power consumption and generator power generation; Calculate the driving power limit, wherein the driving power limit = battery discharge power + generator power generation power - accessory power consumption; Using the driving power limit value to constrain the driver's required torque to obtain a constrained driving power; converting the constrained driving power into driving torque based on vehicle speed; Controlling the driving motor to execute the driving torque; The driving torque is converted into power based on the real-time rotation speed of the driving motor to obtain a predicted value of driving power consumption.

8. The ultra-low temperature power generation control method for an extended range vehicle according to claim 7, characterized in that: The obtaining of the actual power consumption and the actual power generation of the vehicle includes: Obtain the real-time voltage and current data of the generator and calculate the generator power; Acquire voltage and current data of the driving motor after executing the driving torque, and calculate the driving power consumption; Obtain accessory voltage and current data and calculate accessory power consumption; The sum of the driving power consumption and the accessory power consumption is taken as the actual power consumption, and the generator power generation is taken as the actual power generation.

9. An ultra-low temperature power generation control system for an extended range vehicle, characterized in that: Including power domain control module, generator control module, engine control module, power battery control module and power distribution control module; The generator control module is connected to the generator, the engine control module is connected to the engine, the power distribution control module is connected to the distribution box, the power battery control module is connected to the power battery, the distribution box is connected to the generator, the power battery and the load respectively through hard wires, and the power domain controller is connected to the engine control module, the generator control module, the distribution box control module and the drive control module through a network cable; The power domain control module is used to send a predicted value of driving power consumption to the generator control module; The generator control module is used for: When the temperature of the power battery cell is lower than a preset temperature threshold, a driving power consumption prediction value, an accessory power consumption prediction value and a battery discharge power prediction value are obtained; Performing a feedforward operation based on the driving power consumption prediction value, the accessory power consumption prediction value and the battery discharge power prediction value to generate a first generator torque; Obtain the actual power consumption and actual power generation of the vehicle; Performing a PID operation based on the difference between the actual power consumption and the actual power generation to generate a second generator torque; superimposing the first generator torque and the second generator torque to generate a generator target torque; The generator is controlled to execute the generator target torque.

10. The ultra-low temperature power generation control system for an extended-range vehicle according to claim 9, characterized in that: The power domain control module is also used for: Obtain driver demand torque, battery discharge power, accessory power consumption and generator power generation; Calculate the driving power limit, wherein the driving power limit = battery discharge power + generator power generation power - accessory power consumption; Using the driving power limit value to constrain the driver's required torque to obtain a constrained driving power; converting the constrained driving power into driving torque based on vehicle speed; Controlling the driving motor to execute the driving torque; The driving torque is converted into power based on the real-time rotation speed of the driving motor to obtain a predicted value of driving power consumption.

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