Electronic control technology analysis
The electronic control unit is equivalent to the ECU of a conventional automobile, and is the main execution unit for controlling the high-voltage components on the electric vehicle. In addition to motor control, the control of related components such as the car charger, DC-DC unit, etc., is also realized by the electronic control unit.
The core of the electronic control unit is the control of the drive motor. The power unit provider - the power battery provides direct current, and the drive motor requires three alternating current. Therefore, what the electronic control unit is to achieve is a process called inverter in power electronics technology, that is, converting the direct current of the power battery end into the alternating current of the input side of the motor.
In order to realize the inverter process, the electronic control unit needs DC bus capacitors, IGBT and other components to work together. After the current is output from the power battery terminal, the DC bus capacitor is first used to eliminate the harmonic component. After that, by controlling the switch of the IGBT and the cooperation of other control units, the DC power is finally inverted into AC power, and finally used as a power motor. Input Current. As described above, by controlling the frequency of the three input currents of the power motor and the feedback value of the speed sensor and the temperature sensor on the power motor, the electronic control unit finally realizes the control of the motor.
In addition to the control of the motor, the electronic control unit is also the main control mechanism of the components such as the car charger and the DC-DC unit. Charging is just the opposite of motor control. It is necessary to convert the AC power provided by the grid into the DC power of the power battery, which is called the rectification process in power electronics.
The DC-DC unit is a process of charging a 12V battery through a power battery. The electronic control unit needs to convert the high voltage of the power battery end into a low voltage end of the 12V battery to finally realize charging for the new energy vehicle.
