The application of three-dimensional modelling to power frequency changers

The technique is first applied to several known processes encountered in invertors and single-step frequency changers, and it is shown to provide a valuable insight into their mode of operation and the form of their output. In particular, the generation of subharmonic products is explained. The analysis of known processes is then developed to suggest modifications whereby they might be improved. A detailed investigation is pursued into two particular arrangements, with the help of a digital computer simulation and a low power practical model. The results are subjected to methodical evaluation, leading to suggestions for the improvement of existing invertor design and for the development of practical force-commutated modulators.