Advanced time domain method for remote wind farms with LFAC transmission systems: Power transfer and harmonics

This paper presents an advanced time domain model for systems of remote wind farms connected to the power grid via low frequency AC transmission (LFAC). This system contains standard converters as well as cyclo-converters. The time domain model is based on the quadratic integration method. Specifically, the method consist of two steps: (a) quadratization of the models of the constituent parts of the system, and (b) quadratic integration of the quadratic models. The proposed time domain models by the application of the quadratic integration have been demonstrated to be accurate, robust, and reliable as compared to those by the application of other integration methods such as the trapezoidal integration. The goal of this paper is to present this time domain method and the performance of wind farms connected to the power grid via LFAC transmission. Several examples of wind farms with LFAC transmission systems interconnected by a phase-controlled three-phase cycloconverter are presented.