zero voltage switching for 3phase voltage source inverter
a novel soft-switching singlephase
ac–dc–ac converter to give high input power factor and
low current distortion on the rectifier side and provide clean and
stable ac voltage on the inverter side. The proposed converter uses
a new zero voltage switching (ZVS) strategy to get ZVS function.
Besides operating at constant frequency, all semiconductor devices
operate at soft-switching without additional voltage stress.
A significant reduction in the conduction losses is achieved, since
the circulating current for the soft switching flows only through
the auxiliary circuit and a minimum number of switching devices
is involved in the circulating current path, and the rectifier in the
proposed converter uses a single converter instead of the conventional
configuration composed of a four-diode front-end rectifier
followed by a boost converter. An average-current-mode control
is employed in the rectifier side of proposed converter to detect the
transition time and synthesize a suitable low harmonics sinusoidal
waveform for the input current. The sinusoidal pulsewidth modulation
(SPWM) control strategy is employed in the inverter of
proposed converter to achieve good dynamic regulation.