This paper presents the analysis, design and implementation of cost effective sensorless control scheme of Brushless DC Motors (BLDCM). There are several methods proposed in BLDC motor drives to obtain optimum current and torque control with minimum torque pulsation. But while coming to industrial applications, BLDC motor voltage contains harmonics which are caused because of high speed switchi...

The series-parallel resonant converter and its magnetic components are analysed by extended fundamental frequency techniques. The proposed model allows an easy design of the resonant circuit and the integrated transformer and the calculation of the losses of all components of the converter. The purpose of the presented analytic model is an optimisation of the converter system – minimising eithe...

A single phase ac-dc soft switched PFC converter with a LCD snubber is presented for dc output voltage regulation. The LCD snubber cell provides zero current switching (ZCS) turn ON and zero voltage switching (ZVS) turn OFF for the converter switch without increasing current or voltage stress. In this study, steady state analysis of proposed PFC converter is presented in detail and the theoreti...

This paper presents a current-fed full-bridge boost DC-AC-DC converter with transformer isolation operating without switching power dissipation. The output voltage is regulated by dc-ac converter whose frequency changes with a constant turn-off time of transistors. The proposed converter is devoid of parasitic oscillations, as all of the parasitic capacitances and inductances are included in a ...

This paper deals with speed control of DC drive fed from parallel QRC. In this work the GA optimization technique is successfully applied for speed control of QRC fed DC drive. In general PI controllers are used as conventional feedback controllers but the advent of Fuzzy logic controllers (FLC) enhances the effectiveness of control. In addition the drive fed from Zero current switching Quasi-r...

Existing 34, ac-dc low-harmonic rectiifiers are costly and require complex control schemes to minimize input current harmonics. Introduced here are three new classes of low cost 34, acdc high power factorllow harmonic controlled rectifiers. These are derived from parent dc-dc convrter topologies containing boost-type inputs, buck-type inputs and qwsi resonant zero-current-switch (ZCS) buck-type...

A new zero-voltage and zero-current-switching (ZVZCS) full-bridge (FB) pulsewidth modulation (PWM) converter is proposed to improve the performance of the previously presented ZVZCS FB PWM converters. By adding a secondary active clamp and controlling the clamp switch moderately, ZVS (for leading-leg switches) and ZCS (for lagging-leg switches) are achieved without adding any lossy components o...