Compensation of Dead-Time Effect in PWM Inverter

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Compensation of Dead-Time Effect in PWM Inverter [Copy link]

Compensation of Dead-Time Effect in PWM Inverter

Abstract: In a PWM three-phase inverter, the dead time injected to prevent the direct short circuit of two power devices on the same bridge arm will cause a certain error in the inverter output voltage. This paper analyzes the mechanism of the dead time effect and gives two compensation methods.

Keywords: PWM inverter dead time effect compensation

　　In PWM three-phase inverters, since the switch tube has a certain on and off time, in order to prevent the direct conduction of two switch devices on the same bridge arm, a dead time of several microseconds must be set in the control signal. Although the dead time is very short and the output voltage error caused is small, due to the high switching frequency, the superposition value of the error caused by the dead time will cause the waveform distortion of the motor load current, causing the electromagnetic torque to produce a large pulsation phenomenon, thereby reducing the dynamic and static performance and reducing the actual application effect of the switch device.

　　This paper starts with analyzing the mechanism of dead zone effect and seeks a compensation method for the dead zone effect.