A method, device and readable storage medium for thermal management working condition control of a range extender

Abstract

This invention relates to the field of new energy vehicle control technology, specifically to a method, device, and readable storage medium for controlling the thermal management operating conditions of a range extender, comprising the following steps: Step 1, acquiring a first target power, a first temperature, a second temperature, and a third temperature; Step 2, calculating a first target speed; Step 3, if the range extender is overheated, proceed to Step 4; otherwise, proceed to Step 5; Step 4, calculating a second target speed and replacing it with the first target speed; Step 5, calculating a first target torque and transmitting it to the engine controller to control engine output; Step 6, acquiring the actual torque, calculating the target torque, and transmitting it to the motor controller to control motor output, then returning to Step 1. This method solves the problem of range extender overheating while ensuring the normal operation of the range extender and improving the utilization rate of the range extender system.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle control technology, and more specifically, to a method, device, and readable storage medium for controlling the thermal management operating conditions of a range extender. Background Technology

[0002] The thermal management control of range extenders is divided into two main categories: one is the control of the heat dissipation system, and the other is the control of the heat source.

[0003] Currently, the control strategy for the range extender's cooling system is relatively simple. The engine cooling fan's control depends entirely on the engine coolant temperature, which is transmitted from the ECU (Electronic Control Unit) via CAN (Controller Area Network). However, the engine cooling system consists of a large circulation loop and a small circulation loop. When the engine is warm, the coolant only circulates through the small circulation loop, bypassing the radiator. Only when the temperature exceeds a certain threshold does the coolant enter the large circulation loop. Therefore, when the engine is warm, the engine coolant is hot, while the coolant in the radiator remains cold. Since the engine cooling fan's control depends entirely on the coolant temperature, the fan is on after the engine warms up. However, since the coolant in the radiator is cold at this point, the fan's operation is meaningless and only consumes electrical energy, affecting the overall system efficiency.

[0004] Chinese patent CN109733182B discloses a thermal management system for a range-extended electric vehicle. This thermal management system only limits the power of the entire range extender system when the temperature reaches a set value, i.e., it controls the heat source. The range extender's cooling system is divided into an engine cooling system and a motor cooling system. If only one of the cooling systems overheats, but the power of the entire range extender's power generation system is limited, it will inevitably affect the utilization rate of the entire range extender system. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for controlling the thermal management operating conditions of a range extender system to improve its utilization rate.

[0006] A method for controlling the thermal management operating conditions of a range extender includes the following steps:

[0007] Step 1: Obtain the first target power of the range extender at the current moment, and at the same time obtain the first temperature of the engine, the second temperature of the motor, and the third temperature of the motor controller;

[0008] Step 2: Calculate the first target speed of the range extender based on the first target power;

[0009] Step 3: If the first temperature is greater than or equal to a preset first temperature threshold, the second temperature is greater than or equal to a preset second temperature threshold, or the third temperature is greater than or equal to a preset third temperature threshold, then the range extender is determined to be in an overheated state, and proceed to step 4; if the first temperature is less than the first temperature threshold, the second temperature is less than the second temperature threshold, and the third temperature is less than the third temperature threshold, then proceed to step 5.

[0010] Step 4: Calculate the second target speed of the range extender based on the first target speed, and replace the second target speed with the first target speed;

[0011] Step 5: Calculate the first target torque of the range extender based on the first target speed, transmit the first target torque to the engine controller, and control the engine output through the engine controller;

[0012] Step 6: Obtain the actual torque of the engine, calculate the target torque of the range extender based on the actual torque, and transmit the target torque to the motor controller. Control the motor output through the motor controller. After completion, return to step 1.

[0013] Preferably, a speed determination process is further included between step 4 and step 5, the speed determination process including the following steps:

[0014] Step A1: If the first target speed is greater than or equal to the preset limit speed, the range extender is determined to be in an overspeed state, and the process proceeds to step A2; if the first target speed is less than the limit speed, the process proceeds to step 5.

[0015] Step A2: Calculate the second target power of the range extender based on the first target power, and replace the second target power with the first target power. After completion, return to step 2.

[0016] Preferably, in step A2, the second target power of the range extender is calculated based on the first target power and the preset calibration value.

[0017] Preferably, in step 4, the second target speed is calculated based on the first target speed and a preset speed calibration value.

[0018] Preferably, step 6 includes:

[0019] Step 61: Obtain the actual torque and actual speed of the engine;

[0020] Step 62: Calculate the compensation torque based on the first target speed and the actual speed;

[0021] Step 63: Calculate the target torque based on the compensated torque and the actual torque, and transmit the target torque to the motor controller. Control the motor output through the motor controller. After completion, return to step 1.

[0022] Preferably, in step 62, the compensation torque is calculated by a PID controller based on the deviation between the first target speed and the actual speed.

[0023] Preferably, a working condition detection process is included before performing step 1, the working condition detection process including the following steps:

[0024] Step J1: Detect the vehicle's operating condition, which may be power generation, idling, or starting.

[0025] Step J2: Determine the operating condition of the vehicle. If the operating condition is power generation, proceed to step 1. If the operating condition is idling or starting, control the range extender to stop working.

[0026] An apparatus comprising:

[0027] Communication interface;

[0028] At least one processor connected to the communication interface; and

[0029] At least one memory is connected to the processor and stores program instructions that, when executed by the at least one processor, cause the at least one processor to perform the above method.

[0030] A readable storage medium having program instructions stored thereon, which, when executed by a computer, cause the computer to perform the above method.

[0031] Advantages and beneficial effects of the method of this invention: Compared with the prior art, this method no longer uses the traditional power limiting method, but adds a new control algorithm specifically for power allocation when the range extender overheats; specifically as follows: the first target speed is obtained by acquiring the first target power; the first temperature of the engine, the second temperature of the motor, and the third temperature of the motor controller are acquired, and the range extender is determined to be in an overheated state by comparing with the preset corresponding temperature thresholds; when the range extender is overheated, the first target speed is recalculated, and the obtained second target speed replaces the first target speed; the first target torque of the range extender is calculated by the first target speed, and the first target torque is transmitted to the engine controller, which controls the engine output to achieve the effect of cooling the range extender; finally, the target torque of the range extender is calculated by acquiring the actual torque, and the target torque is transmitted to the motor controller, which controls the motor output. After completion, the process returns to step 1 to form a loop, which solves the problem of range extender overheating. At the same time, this method also ensures the normal operation of the range extender and improves the system utilization rate. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating the process of the method of the present invention;

[0033] Figure 2 This is a detailed flowchart of the rotation speed determination process in the method of the present invention;

[0034] Figure 3 This is a detailed flowchart of step 6 of the method of the present invention;

[0035] Figure 4 This is a detailed flowchart of the working condition detection process in the method of the present invention;

[0036] Figure 5 The illustration schematically shows a storage unit for holding or carrying program code that implements the method according to this application;

[0037] Figure 6 A block diagram of an electronic device for performing the method according to this application is shown schematically. Detailed Implementation

[0038] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0039] Combination Figure 1 As shown, a method for controlling the thermal management of a range extender includes the following steps:

[0040] Step 1: Obtain the first target power of the range extender at the current moment, and at the same time obtain the first temperature of the engine, the second temperature of the motor, and the third temperature of the motor controller;

[0041] Step 2: Calculate the first target speed of the range extender based on the first target power;

[0042] Step 3: If the first temperature is greater than or equal to the preset first temperature threshold, the second temperature is greater than or equal to the preset second temperature threshold, or the third temperature is greater than or equal to the preset third temperature threshold, then the range extender is determined to be in an overheated state, and proceed to step 4; if the first temperature is less than the first temperature threshold, the second temperature is less than the second temperature threshold, and the third temperature is less than the third temperature threshold, then proceed to step 5.

[0043] Step 4: Calculate the second target speed of the range extender based on the first target speed, and replace the second target speed with the first target speed;

[0044] Step 5: Calculate the first target torque of the range extender based on the first target speed, and transmit the first target torque to the engine controller, and control the engine output through the engine controller;

[0045] Step 6: Obtain the actual torque of the engine, calculate the target torque of the range extender based on the actual torque, and transmit the target torque to the motor controller. The motor controller controls the motor output. After completion, return to step 1.

[0046] Specifically, the range extender controller obtains the first target power of the range extender in real time, and at the same time obtains the first temperature of the engine, the second temperature of the motor, and the third temperature of the motor controller.

[0047] Then, the range extender controller will obtain the first target engine speed based on the target power. The target power can be obtained by looking up a table, as shown in the table below:

[0048] Target speed 1500 2000 2500 3000 3500 4000

[0049] Then, if the first temperature is greater than or equal to the preset first temperature threshold, the second temperature is greater than or equal to the preset second temperature threshold, or the third temperature is greater than or equal to the preset third temperature threshold, the range extender controller will determine that the range extender is in an overheated state if any of these conditions are met. These three temperature thresholds are three calibrable values, and different values ​​are set according to different objects. After completion, the next step is performed.

[0050] To further optimize this step, the range extender controller will calculate the second target speed based on the first target speed and the preset speed calibration value.

[0051] Specifically, the range extender controller calculates the second target speed of the range extender based on the first target speed and replaces the second target speed with the first target speed; specifically, it increases the first target speed by 100 r / min to obtain the new second target speed.

[0052] If it is determined that the range extender is not overheated, step 5 will be executed directly, skipping the step of increasing the speed and directly calculating the first target torque.

[0053] Next, the range extender calculates its first target torque based on the first target speed and transmits it to the engine controller, which then controls the engine output. The specific calculation is as follows:

[0054]

[0055] in,

[0056] T1 is the first target torque;

[0057] P1 is the target power;

[0058] N1 is the first target rotational speed.

[0059] Finally, the range extender controller obtains the actual torque of the engine, calculates the target torque of the range extender based on the actual torque, and transmits the target torque to the motor controller. The motor controller then controls the motor output. After completion, it returns to the first step, that is, returns to step 1 to obtain the first target power of the range extender at the current moment, and also obtains the first temperature of the engine, the second temperature of the motor, and the third temperature of the motor controller.

[0060] Compared with existing technologies, this method no longer uses the traditional power limiting approach. Instead, it adds a new control algorithm specifically for power allocation when the range extender overheats. Specifically, it obtains a first target speed by acquiring a first target power, and acquires a first temperature of the engine, a second temperature of the motor, and a third temperature of the motor controller. By comparing these temperatures with preset temperature thresholds, it determines whether the range extender is overheating. When the range extender overheats, it recalculates the first target speed and replaces it with the obtained second target speed. It then calculates the first target torque of the range extender using the first target speed and transmits it to the engine controller. The engine controller then controls the engine output to cool the range extender. Finally, it calculates the target torque of the range extender using the acquired actual torque and transmits it to the motor controller. The motor controller then controls the motor output. After completion, it returns to step 1 to form a loop. This method solves the problem of range extender overheating and also ensures the normal operation of the range extender, improving system utilization.

[0061] like Figure 2 As shown, in a preferred embodiment of the present invention, a speed determination process is further included between step 4 and step 5. The speed determination process includes the following steps:

[0062] Step A1: If the first target speed is greater than or equal to the preset limit speed, the range extender is determined to be in an overspeed state, and the process proceeds to step A2; if the first target speed is less than the limit speed, the process proceeds to step 5.

[0063] Step A2: Calculate the second target power of the range extender based on the first target power, and replace the second target power with the first target power. After completion, return to step 2.

[0064] Specifically, the range extender controller determines whether the first target speed of the range extender exceeds the preset limit speed. The limit speed is also determined by a calibration value, which is set to different values ​​depending on the object.

[0065] To further optimize step A2, the range extender controller calculates the second target power of the range extender based on the first target power and the preset calibration value.

[0066] Specifically, if the range extender controller detects that the first target speed of the range extender exceeds the limit speed, it determines that the range extender is in an overspeed state. The range extender controller will then control the target power of the range extender to be reduced by 10% from the original target power in order to reduce the speed.

[0067] like Figure 3 As shown, in a preferred embodiment of the present invention, step 6 includes:

[0068] Step 61: Obtain the engine's actual torque and actual speed;

[0069] Step 62: Calculate the compensation torque based on the first target speed and the actual speed;

[0070] Step 63: Calculate the target torque based on the compensated torque and the actual torque, and transmit the target torque to the motor controller. The motor controller then controls the motor output. After completion, return to step 1.

[0071] To further optimize the above scheme, in step 62, the range extender controller calculates the compensation torque based on the deviation between the first target speed and the actual speed using a PID controller.

[0072] Then, the range extender controller calculates the target torque based on the compensation torque and the actual torque. The specific calculation formula is as follows:

[0073] T3 = T2 + T q

[0074] in,

[0075] T3 is the target torque;

[0076] T2 is the actual torque;

[0077] T q To compensate for torque.

[0078] Simultaneously, the target torque is transmitted to the motor controller, which controls the motor output. After completion, the process returns to step 1 to reacquire the first target power of the range extender at the current moment, and simultaneously acquires the first temperature of the engine, the second temperature of the motor, and the third temperature of the motor controller.

[0079] In a preferred embodiment of the present invention, a working condition detection process is further included before performing step 1. The working condition detection process includes the following steps:

[0080] like Figure 4 As shown, step J1 involves detecting the vehicle's operating condition, which can be either generator operation, idling operation, or starting operation.

[0081] Step J2: Determine the vehicle's operating condition. If the operating condition is power generation, proceed to step 1. If the operating condition is idling or starting, control the range extender to stop working.

[0082] like Figure 5 As shown, a device includes:

[0083] Communication interface;

[0084] At least one processor connected to a communication interface; and

[0085] At least one memory is connected to a processor and stores program instructions that, when executed by at least one processor, cause at least one processor to perform the above method.

[0086] like Figure 6 As shown, a readable storage medium stores program instructions thereon, which, when executed by a computer, cause the computer to perform the above methods.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the thermal management operating conditions of a range extender, comprising the following steps: Step 1: Obtain the first target power of the range extender at the current moment, and at the same time obtain the first temperature of the engine, the second temperature of the motor, and the third temperature of the motor controller; Step 2: Calculate the first target speed of the range extender based on the first target power; Step 3: If the first temperature is greater than or equal to a preset first temperature threshold, the second temperature is greater than or equal to a preset second temperature threshold, or the third temperature is greater than or equal to a preset third temperature threshold, then the range extender is determined to be in an overheated state, and proceed to step 4; if the first temperature is less than the first temperature threshold, the second temperature is less than the second temperature threshold, and the third temperature is less than the third temperature threshold, then proceed to step 5. Step 4: Calculate the second target speed based on the first target speed and the preset speed calibration value, and replace the second target speed with the first target speed; Step 5: Calculate the first target torque of the range extender based on the first target speed, transmit the first target torque to the engine controller, and control the engine output through the engine controller; Step 6: Obtain the actual torque of the engine, calculate the target torque of the range extender based on the actual torque, and transmit the target torque to the motor controller. Control the motor output through the motor controller. After completion, return to step 1.

2. The range extender thermal management operating condition control method according to claim 1, characterized in that, Between step 4 and step 5, there is also a speed determination process, which includes the following steps: Step A1: If the first target speed is greater than or equal to the preset limit speed, the range extender is determined to be in an overspeed state, and the process proceeds to step A2; if the first target speed is less than the limit speed, the process proceeds to step 5. Step A2: Calculate the second target power of the range extender based on the first target power, and replace the second target power with the first target power. After completion, return to step 2.

3. The range extender thermal management operating condition control method according to claim 2, characterized in that, In step A2, the second target power of the range extender is calculated based on the first target power and the preset calibration value.

4. The range extender thermal management operating condition control method according to claim 1, characterized in that, Step 6 includes: Step 61: Obtain the actual torque and actual speed of the engine; Step 62: Calculate the compensation torque based on the first target speed and the actual speed; Step 63: Calculate the target torque based on the compensated torque and the actual torque, and transmit the target torque to the motor controller. Control the motor output through the motor controller. After completion, return to step 1.

5. The range extender thermal management operating condition control method according to claim 4, characterized in that, In step 62, the compensation torque is calculated by a PID controller based on the deviation between the first target speed and the actual speed.

6. The range extender thermal management operating condition control method according to claim 1, characterized in that, Before performing step 1, a working condition detection process is also included, which includes the following steps: Step J1: Detect the vehicle's operating condition, which may be power generation, idling, or starting. Step J2: Determine the operating condition of the vehicle. If the operating condition is power generation, proceed to step 1. If the operating condition is idling or starting, control the range extender to stop working.

7. A device, characterized in that, include: Communication interface; At least one processor connected to the communication interface; as well as At least one memory, connected to the processor and storing program instructions, which, when executed by the at least one processor, cause the at least one processor to perform the range extender thermal management operating condition control method according to any one of claims 1-6.

8. A readable storage medium having program instructions stored thereon, characterized in that, When the program instructions are executed by a computer, the computer performs the range extender thermal management operating condition control method according to any one of claims 1-6.

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