MCU is a unique core power electronic unit of new energy vehicles. By receiving vehicle driving control instructions from VCU, the MCU controls the motor to output the specified torque and speed to drive the vehicle. To realize the conversion of the DC energy of the power battery into the required high voltage alternating current, and drive the motor body output mechanical energy. At the same time, MCU has the function of motor system fault diagnosis protection and storage.
There are many parameters set in the MCU, and each parameter has a certain selection range. In use, it is often encountered that the MCU cannot work normally due to improper setting of individual parameters (parameter setting is set through CAN communication or simulator). Therefore, the relevant parameters must be set correctly.
1. Control mode: speed control, pitch control, PID control or other methods. After the control method is adopted, static or dynamic identification is generally carried out according to the control accuracy.
2. Lowest operating frequency: that is, the minimum speed of the drive motor. When the drive motor runs at low speed, its heat dissipation performance is very poor (air-cooled type), and the electric machine runs at low speed for a long time, which will cause the drive motor to burn. At low speeds, the current in the cable will also increase, which will also cause the cable to heat.
3. Maximum operating frequency: the general MCU maximum frequency to 60Hz, and some even to 400 Hz, high frequency will make the drive motor run at high speed, which for ordinary motors, the bearing can not run for a long time over a fixed speed, whether the rotor of the motor can withstand such centrifugal force.
4. Carrier frequency: the higher the carrier frequency is set, the larger the high-order harmonic component, which is closely related to the length of the cable, motor heating, cable heating, IGBT heating and other factors.
5. Motor parameters: The MCU sets the power, current, voltage, speed and maximum frequency of the motor in the parameters, which can be directly obtained from the nameplate of the drive motor.
6. Frequency hopping: at a certain frequency point, resonance phenomenon may occur, especially when the whole device is relatively high; When controlling the compressor, the surge point of the compressor (air conditioning compressor) should be avoided.
Hello, the main parameters of MCU chip include:
1. Processor core: The processor core of the MCU chip determines its computing power and running speed.
2. Memory: The memory of the MCU chip includes flash memory, RAM and EEPROM, etc., for storing program code and data.
3. Clock: The higher the clock frequency of the MCU chip, the faster it runs.
4. Input\/output interface: The input\/output interface of the MCU chip is used to communicate with external devices, such as serial ports, SPI, I2C and other interfaces.
5. Power management: The power management module of the MCU chip can effectively manage the power consumption of the chip and extend the service life of the chip.
6. Size and package: the size and package form of the MCU chip determine its application scenarios in integrated circuits.