ABSTRACT
The requirements of three-phase CSI for threephase PWM signal is only two switches turn-on, which one lies in the upper bridge arm and the other lies in the lower bridge arm at any time (except during commutation). If only one switch is turned on, the current will lose the continuity and the DC inductance will produce an extremely high voltage which will damage to the switches. If more than two switches are simultaneously turned on, PWM current will no longer meet the defined switching waveform. This is the important reason that the three-phase CSI-PWM control becomes more complex than voltage-type (Zhaokai Yuan 2008).
