Electric vehicle motor derating control system
By working in concert with the throttle position sensor and the vehicle controller, the problem of network communication failure in the controller area was solved, enabling safe driving of electric vehicles under abnormal conditions and reducing costs.
Patent Information
- Application Number
- CN202211103703.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Priority Date
- 2021-11-04
- Filing Date
- 2022-09-09
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2042-09-09
AI Technical Summary
Controller area network communication is prone to failure, leading to vehicle loss of control and communication anomalies, increasing hardware costs and development time.
Through the coordinated operation of the throttle position sensor, vehicle controller, and motor controller, digital control signals are transmitted via a data bus and converted into load-reducing control signals in abnormal conditions to control motor operation.
To prevent vehicles from going out of control when communication is abnormal, reduce product development costs and time, and reduce the number of physical wiring.
Smart Images
Figure CN116061701B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a motor load reduction control system, in particular to an electric vehicle motor load reduction control system. BACKGROUND
[0002] The conventional vehicle control system transmits signals to the motor controller through the throttle position sensor (TPS) for motor control. Since the throttle position sensor is connected to the motor controller by a hardware line, the vehicle manufacturer fine-tunes the throttle response of the motor controller, but the motor controller manufacturer does not understand the vehicle throttle control, so the motor controller firmware is modified many times, which cannot effectively shorten the motor controller development schedule, affecting the vehicle production time.
[0003] Currently, the control signal line of the throttle position sensor is connected to the vehicle control unit (VCU) first, and then the vehicle control unit controls the motor controller to operate. There are two methods at present, the first method is to read the control signal of the throttle position sensor by the vehicle control unit, and then provide the control signal to the motor controller in the form of analog signal. But since the conversion of the control signal needs to be converted by the digital-analog converter of the hardware, the cost of hardware setting is increased. The second method is that the vehicle control unit directly gives orders to the motor controller by the controller area network (CAN) communication.
[0004] As mentioned above, the vehicle control unit uses the controller area network to give orders to the motor controller, which can certainly reduce the hardware development cost, shorten the model development time and improve the portability of the vehicle control strategy. But since the communication of the controller area network is commonly used by multiple vehicle components, the problem of communication failure of the controller area network is easily caused, which causes the vehicle to lose control and causes damage to personnel and property when the user encounters communication abnormalities in the controller area network.
[0005] Therefore, how to provide an electric vehicle motor load reduction control system has become an urgent research topic. SUMMARY
[0006] [Problems to be Solved by the Invention]
[0007] The problem of communication failure of the controller area network is solved.
[0008] [Technical Means for Solving the Problems]
[0009] In view of the above problems, the present application discloses a motor control system for electric vehicle, which comprises a throttle position sensor (TPS), a vehicle controller, a motor controller and a motor. The throttle position sensor detects a throttle signal. The vehicle controller is connected to the throttle position sensor and receives the throttle signal. The motor controller is connected to the vehicle controller through a signal line and connected to the vehicle controller through a data bus. The motor is connected to the motor controller. When the vehicle controller determines that the data bus is in an abnormal state, the vehicle controller converts the throttle signal into a load reduction control signal and transmits the load reduction control signal to the motor controller through the data bus. The motor controller controls the motor according to the load reduction control signal.
[0010] In view of the above problems, the present application discloses a motor control system for electric vehicle, which comprises a throttle position sensor (TPS), a vehicle controller, a motor controller and a motor. The throttle position sensor detects a throttle signal. The vehicle controller is connected to the throttle position sensor and receives the throttle signal. The motor controller is connected to the vehicle controller through a signal line and connected to the vehicle controller through a data bus. The motor is connected to the motor controller. When the vehicle controller determines that the data bus is in an abnormal state, the vehicle controller converts the throttle signal into a load reduction control signal and transmits the load reduction control signal to the motor controller through the data bus. The motor controller controls the motor according to the load reduction control signal.
[0011] [Effects of the Invention]
[0012] The present application determines whether the digital control signal transmitted by the data bus is erroneous, missing or periodically changed by the vehicle controller or the motor controller. When the abnormal state occurs, the motor continues to operate in the load reduction mode. The user can drive the electric vehicle at a lower power, and the vehicle cannot be driven or out of control when the communication of the data bus is abnormal. In addition, the motor control system for electric vehicle can reduce the product development cost and the firmware development time, and reduce the number of physical wiring. BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1A FIG. 1 is a block diagram of the motor control system for electric vehicle of the present application; and
[0014] FIG. 1B FIG. 3 is a block diagram of the motor control system for electric vehicle of the present application comprising a buffer.
[0015] List of reference signs
[0016] 1: electric vehicle motor load down control system
[0017] 11: throttle position sensor
[0018] 12: vehicle control unit
[0019] 121: analog / digital converter
[0020] 122: processing unit
[0021] 12A: input terminal
[0022] 12B: first transmission terminal
[0023] 12C: second transmission terminal
[0024] 13: motor control unit
[0025] 13A: third transmission terminal
[0026] 13B: fourth transmission terminal
[0027] 13C: motor connection terminal
[0028] 14: motor
[0029] 15: buffer
[0030] 15A: first connection terminal
[0031] 15B: second connection terminal
[0032] W: signal line
[0033] B: data bus DETAILED DESCRIPTION
[0034] Reference will now be made to FIG. 1AFigure 1 is a block diagram of a motor load reduction control system for an electric vehicle according to a first embodiment of the present application. The motor load reduction control system 1 includes a throttle position sensor (TPS) 11, a vehicle controller 12, a motor controller 13, and a motor 14. The throttle position sensor 11 generates an analog throttle signal. The vehicle controller 12 has an input terminal 12A, a first transmission terminal 12B, and a second transmission terminal 12C. The input terminal 12A is connected to the first transmission terminal 12B and the throttle position sensor 11. The vehicle controller 12 includes an analog / digital converter 121 and a processing unit 122. The analog / digital converter 121 is connected to the input terminal 12A to receive the throttle signal and convert the throttle signal into a digital control signal. The processing unit 122, which can be a central processing unit (CPU) integrated circuit chip, is connected to the analog / digital converter 121 and the second transmission terminal 12C and receives the digital control signal. The motor controller 13 has a third transmission terminal 13A, a fourth transmission terminal 13B, and a motor connection terminal 13C. The third transmission terminal 13A is connected to the first transmission terminal 12B of the vehicle controller 12 via a signal line W. The fourth transmission terminal 13B is connected to the second transmission terminal 12C of the vehicle controller 12 via a data bus B, which can be a controller area network (CAN) bus. The motor 14 is connected to the motor connection terminal 13C of the motor controller 13. In the first embodiment of the present application, when the processing unit 122 of the vehicle controller 12 determines that the data bus B has an abnormal state, the processing unit 122 converts the throttle signal into a load reduction control signal and transmits the load reduction control signal to the motor controller 13 via the data bus B. The motor controller 13 controls the motor 14 to operate according to the load reduction control signal.
[0035] Referring to FIG. 1B Figure 2 is a block diagram of the motor load reduction control system 1 of the first embodiment of the present application including a buffer. In this embodiment, the vehicle controller 12 further includes a buffer 15. The buffer 15 includes a first connection terminal 15A and a second connection terminal 15B. The first connection terminal 15A is connected to the input terminal 12A and the analog / digital converter 121. The second connection terminal 15B is connected to the first transmission terminal 12B. In other words, the throttle position sensor 11 transmits the throttle signal to the third transmission terminal 13A of the motor controller 13 via the input terminal 12A, the first connection terminal 15A, the second connection terminal 15B, and the first transmission terminal 12B of the vehicle controller 12.
[0036] In the present application, the abnormal state includes three conditions, which are described as follows. The first abnormal state is a condition that the packet error rate of the digital control signal transmitted by the data bus B exceeds a preset value. For example, the packet error rate can be detected by a cyclic redundancy check (CRC) method. Further, in data transmission, the number of bit errors is the number of bits in the received data stream that are changed due to noise, interference, distortion, or bit synchronization errors. The bit error rate (BER) refers to the number of error bits per unit time. Since the throttle signal has been converted into a digital control signal by the analog / digital converter 121 and transmitted by the data bus B, the accuracy of the digital control signal transmitted by the data bus B can be confirmed by checking the packet error rate of the digital control signal transmitted by the data bus B. For example, when the digital control signal includes 128 packets, if more than 70 packets out of the 128 packets have errors, it indicates that the data bus B is in an abnormal state, and the processing unit 122 converts the throttle signal into a load reduction control signal and transmits the load reduction control signal to the motor controller 13 by the data bus B. The motor controller 13 controls the operation of the motor 14 according to the load reduction control signal.
[0037] The second abnormal state is a condition that the packet loss rate of the digital control signal transmitted by the data bus B exceeds a preset value. Similarly, whether an abnormal state occurs can be determined by checking whether the proportion of the number of packets lost in the digital control signal transmitted by the data bus B exceeds a preset value. For example, when 50 packets are lost out of the 128 packets of the digital control signal transmitted, it indicates that the data bus B is in an abnormal state, and the processing unit 122 converts the throttle signal into a load reduction control signal and transmits the load reduction control signal to the motor controller 13 by the data bus B. The motor controller 13 controls the operation of the motor 14 according to the load reduction control signal.
[0038] The third abnormal state is a condition that the packet period of the digital control signal transmitted by the data bus B changes by more than a preset value. Since the transmission of the packet is a fixed period, when the period of the packet transmission is greater than a preset value, it indicates that the data bus B is in an abnormal state. For example, if the period of the packet of the digital control signal transmitted is 50 per second, when the period of the transmitted packet changes to 60 per second, it indicates that the data bus B is in an abnormal state, and the processing unit 122 converts the throttle signal into a load reduction control signal and transmits the load reduction control signal to the motor controller 13 by the data bus B. The motor controller 13 controls the operation of the motor 14 according to the load reduction control signal.
[0039] In the present application, when the data bus B does not have an abnormal state, the motor controller 13 controls the motor 14 to operate according to the digital control signal transmitted by the data bus B.
[0040] The first embodiment described above is to determine whether the data bus B has an abnormal state by the vehicle controller 12, in the second embodiment of the present application, the motor controller 13 determines whether the data bus B has an abnormal state, and when the motor controller 13 determines that the data bus B has an abnormal state, the accelerator signal is received through the signal line W, and a load reduction control signal is generated according to the accelerator signal, so as to control the motor 14 to operate according to the load reduction control signal, that is, when the motor controller 13 determines that the data bus B has an abnormal state, the digital control signal received from the data bus B is not processed.
[0041] The first embodiment described above is to determine whether the data bus B has an abnormal state by the vehicle controller 12, the second embodiment described above is to determine whether the data bus B has an abnormal state by the motor controller 13, in the third embodiment of the present application, the vehicle controller 12 and the motor controller 13 determine whether the data bus B has an abnormal state at the same time, the details are described above, and will not be described here.
[0042] Accordingly, the present application determines whether the digital control signal transmitted by the data bus has an error, omission or periodic change state by the vehicle controller or the motor controller, and continues to run in the load reduction mode when the abnormal state occurs, so that the user can drive the electric vehicle at a lower power, and avoid the vehicle unable to drive or out of control when the communication of the data bus is abnormal. In addition, the electric vehicle motor load reduction control system of the present application can reduce the product development cost and the firmware development time, and can reduce the number of physical wiring.
[0043] In summary, only the embodiments or examples of the technical means adopted to solve the problems are described, and the scope of the present application is not limited. That is, any equivalent changes and modifications made in accordance with the meaning of the claims of the present application or within the scope of the present application are covered by the present application.
Claims
1. An electric vehicle motor de-rating control system, characterized by, A throttle position sensor detects a throttle signal. A vehicle controller has an input terminal, a first transmission terminal, and a second transmission terminal, the input terminal is connected to the first transmission terminal and the throttle position sensor, and receives the throttle signal. A motor controller has a third transmission terminal, a fourth transmission terminal, and a motor connection terminal, the third transmission terminal is connected to the first transmission terminal of the vehicle controller through a signal line, and the fourth transmission terminal is connected to the second transmission terminal of the vehicle controller through a data bus. A motor is connected to the motor controller. The vehicle controller transmits a digital control signal to the motor controller through the data bus; when the vehicle controller determines that the data bus has an abnormal state, the vehicle controller converts the throttle signal into a load shedding control signal, and transmits the load shedding control signal to the motor controller through the data bus, and the motor controller controls the motor according to the load shedding control signal. A throttle position sensor detects a throttle signal.
2. An electric vehicle motor de-rating control system, characterized by, A vehicle controller has an input terminal, a first transmission terminal, and a second transmission terminal, the input terminal is connected to the first transmission terminal and the throttle position sensor, and receives the throttle signal. A motor controller has a third transmission terminal, a fourth transmission terminal, and a motor connection terminal, the third transmission terminal is connected to the first transmission terminal of the vehicle controller through a signal line, and the fourth transmission terminal is connected to the second transmission terminal of the vehicle controller through a data bus. A motor is connected to the motor controller. The vehicle controller transmits a digital control signal to the motor controller through the data bus; when the motor controller determines that the data bus has an abnormal state, the motor controller receives the throttle signal through the signal line, and generates a load shedding control signal according to the throttle signal, to control the motor according to the load shedding control signal. The abnormal state is when the packet error rate of the data bus transmitting the digital control signal exceeds a preset value. The abnormal state is when the transmission packet loss rate of the data bus transmitting the digital control signal exceeds a preset value.
3. The electric vehicle motor derating control system of claim 1 or 2, wherein, The abnormal state is when the packet cycle of the data bus transmitting the digital control signal is greater than a preset value.
4. The electric vehicle motor derating control system of claim 1 or 2, wherein, The vehicle controller includes a processing unit that determines that the data bus has the abnormal state.
5. The electric vehicle motor derating control system of claim 1 or 2, wherein, The vehicle controller further includes:
6. The electric vehicle motor derating control system of claim 1, wherein, An analog / digital converter converts the throttle signal into the digital control signal, 7. The electric vehicle motor derating control system of claim 6, wherein, The processing unit receives the digital control signal.
Citation Information
Patent Citations
Power system switching scheme based on double CAN
CN107364439A