Abstract:Mileage is a major technical bottleneck in the application of electric vehicles. Therefore, improvement of the efficiency of the motor drive system is a key technology to breaking through the bottleneck. High power losses and low efficiencies of the inverter can not only affect the mileage of electric cars, but also cause high cooling system load of electric vehicles and limit the current output capacity of the inverter. In this paper, the sevensegment SVPWM, flattop SVPWM, and halffrequency SVPWM are compared and used in combination. That is, different modulation algorithms are used under different working conditions of electric vehicle, which makes the system have a low inverter loss and high torque accuracy, so as to improve their market competitiveness.