Description:
Power DevicesStructure, Characteristics, Ratings of SCR, GTO, IGBT, Power diode comparison of above devices with Power MOSFET and Power BJT Driver Circuits (isolated and nonisolated) for IGBT & SCR. Protection circuits for IGBT and SCR.Single and Threephase AC/DC ConverterConcept of line commutation.Singlephase half and fully controlled, Three phase half and fully controlled bridges : Circuit diagram, Operation and waveforms for resistive and level (highly inductive) loads for above circuits.An analysis of output voltage and supply current for singlephase bridges including the following performance parameters :Average and RMS output voltage, Fourier series expressions for supply current. Derivation of fundamental power factor (Displacement power factor), Current distortion factor, Active, Reactive and apparent power.Single and Threephase DC/AC InvertersCircuit diagram, Operation and waveforms for single phase full bridge and Push pull inverters.Switching techniques for obtaining square, Quasisquare and sinusoidal PWM output waveforms.Use of pulse width modulated IC's for Inverter control.Fourier analysis of quasisquare waveform and harmonic load currents for R and RL loads.Circuit diagram, Operation and waveforms for three phase voltage source bridge inverters for 120 degree and 180 degree conduction for balanced star resistive load.Switched and Resonant DC/DC ConvertersControl of DC/DC converter.Circuit diagram, Waveforms and operation (output voltage calculation) of step down chopper (Buck converter), Step up chopper (Boost converter) and 2quadrant type C chopper.Circuit diagram, Waveforms, Operation, Analysis and design aspects of Fly back converter (SMPS) including magnetics.Need for resonant converters :Circuit diagram, Waveforms and operation of SLR half bridge DC/DC converter in low frequency (discontinuous conduction) mode.Single and Threephase AC/AC Power ControllersPrinciple of integral cycle and phase angle control.Circuit diagram, Waveforms, Operation and analysis of singlephase full wave controller with R and RL load.Study of triac based single phase controller.Use of IC TCA 785 in phase angle control.Circuit diagram, Waveforms and operation of three phase full wave controller with balanced star resistive load.Applications1) ONline and OFFline UPS with battery AH, Backup time, Battery charger rating, Calculations. 2) Electronic ballast : Characterisitcs of fluorescent lamps and advantages over conventional ballast.3) Single phase separately excited DC motor drive.4) HVDC transmission one line diagram, Twelve pulse converter, Arrangement and advantages over HVAC transmission.5) HF induction heating.6) Electric welding. more >>
