| While advocating energy saving and emission reduction, to use green low-carbon new energy vehicles to replace existing fuel powered vehicles, has become a new step major strategic plan to implement sustainable development in our country. Low-speed electric vehicles are the stage product, which is just derived to meet the needs of the market spontaneously during the development process of new energy vehicles. It has significant advantages of light pollution, low energy consumption, low cost and easy charging and its development prospects are inestimable.This paper selects a PMSM with small volume, high efficiency, high power density as the driving motor of the vehicle and designs a PMSM drive controller for the low-speed electric vehicle, which is based on STM32F103ZET6 core chip. The controller is driven by multiple power MOSFET, and large multiple overload current is allowed when it starts. In the paper, the design of hardware modules that includes system power module, pre-charge control module, contactor and drive module,inverter drive module and signal acquisition and conditioning circuit is introduced in detail. In terms of software, this paper adopts modular design idea. Through theμVersion4 integrated development environment, the program writing of speed and current double closed loop control system, which includes pre-charging processing module, electronic throttle signal processing module, motor working state switching module, rotor position angle calculation module, dead time compensation module and is based on SVPWM algorithm, is finished.On the basis of the debugging of hardware and software of the controller, a lot of bench load tests are carried out. These experiments are mainly to test the phase current waveform, output torque and speed of the motor in the simulated road and ramp road conditions. Meanwhile, by analyzing the experimental data, system control parameters are modified. Finally, the PMSM and its controller are installed in the vehicle. The results of actual road test show that the designed controller has goodperformance and meets the expected design requirements. |
