Application of Load Current Forward Compensating in Digital Voltage Regulation for Doubly Salient Brushless DC Generator

A doubly salient brushless high voltage DC power system, that is composed of a 12/8 pole electromagnetic doubly salient (EMDS) generator and a diode bridge rectifier, is developed in this paper. The operational principle of voltage regulating system under sudden load changes is analyzed, and the effect of the filter capacitance of tri-phase rectifying bridge on dynamic characteristics for the EMDS brushless DC generator system is also discussed here. In order to improve further the dynamic characteristic further, the PI algorithm which includes load-current forward compensating (LCFC) control is developed. Then, the proposed LCFC method was compared with traditional PI. The experimental results verify the theoretical analysis. The voltage change is reduced during loading and unloading transient processes. The developed control scheme can be extended to the other digital voltage regulation systems of DC generators.