Novel Speed Control Method for Load Commutation Inverters for Synchronous Condensers

Abstract

This article introduces a novel control algorithm for enhancing the speed control dynamics of load commutation inverters (LCIs) so that the driving time and power consumption is minimized during the grid synchronization of synchronous condensers. In particular, the proposed speed control method is designed as a single loop controller by omitting a dc current controller which is an inner loop in the conventional method to reduce time delays and achieve expand the bandwidth compared to the conventional method. Furthermore, the dc-link current reference is optimally determined in order to improve the power efficiency in the steady state and permit torque reference for speed control. The proposed method showed a 40.2% reduction in the time to achieve synchronous condenser's requirements for grid synchronization compared to the conventional method in simulations based on the parameters of an actual generator system. The validity, feasibility and effectiveness of the proposed method have been verified by experimental results. © 1986-2012 IEEE.