Universal Input Zero Current Switched High Power Factor Variable Speed DC Drive

The objective of this paper is to propose a simple, reliable light weight, universal input (AC/DC) compatible, economic variable speed DC drive, with simultaneous improvement in motor performance and input power quality and with higher efficiency and augmentable power handling capacity with ease. A high frequency quasi resonant zero current switched dc drive with single switch operating in quasi resonant zero current switching mode is proposed. Armature ripples discontinuous conduction mode of operations is reduced. Increase in chopping frequency has the advantageous effects on both the amplitudes and the orders of load and line current harmonics. A zero current, soft switched dc drive has been designed analyzed fabricated. The results are compared with low frequency hard switched dc drive.