A New Method for Developing the Control Scheme of a CVVF Cycloconverter

This paper introduces a new method for developing the control scheme of phase-controlled cycloconverters. In this method, all the input cosine waves are transformed into a set of parallel lines by means of coordinate transformation. As a result, arguments on the time process of both firing delays and control flows are made much easier than by the conventional method in which all the arguments are made in the time domain. As an application, a CVVF-type noncirculating current cycloconverter is controlled using this method. The results show that the proposed method is useful in pursuing appropriate schemes for Micro-computer-based control.