The Performance and Characterstics of Thyristor Power Control Systems

Abstract

The three basic a .c. power control systems, phase control, integral cycle and tap-changing, have been investigated. A large selection of computer programmes has been established for the three systems although all systems I have not been covered to the same depth. A number of programmes have been verified by practical investigations and also in a limited number of cases by comparisons with already known results. The major part of the thesis was the computer programme for all cases and a full investigation of the phase control system and the integral cycle system. An attempt has been made to present the information in a form not previously available and in particular the graphical representation whereby a choice can be easily established to obtain the following: a) The minimum firing angle variation for a particular voltage or power deviation. This could have economic advantages. b) The best firing angle range for minimum distortion, in the output waveform. c) The effect of removing harmonies by an output filter. d) The optimum condition with respect to the power factor presented to the supply.