DC Motor Detection and Protection Based On Bipolar PWM Drive

Based on the analysis of a DC motor driven by bipolar pulse width modulation (PWM), a detection method is proposed to protect the motor drive circuit from short circuit and multiple current sampling. The circuit uses a multiplexer to control four power transistors, in which the power transistors on the same side are in complementary conduction mode, and the current points are sampled at the same point. The root mean square value, the blocking current value and the short - circuit current value are taken respectively. The driving circuit is protected in different places through the three different types of current values mentioned above. Compared with the traditional bipolar PWM drive circuit, this circuit can avoid the short circuit of power transistor, and can better protect the current and prevent the driving circuit and motor from burning down.