Research on self-excited initiation of a Medium-voltage DC (MVDC) multiphase synchronous generator-rectifier system

Abstract

This paper has described the excitation system of a Medium-voltage DC (MVDC) multiphase synchronous generatorrectifier system and calculated the minimum frequency of the pilot-exciter needed for self-excited initiation. On this basis, a double closed-loop V/F control method is proposed according to the classical PI control algorithm for self-excited initiation. With the method, a prototype is constructed for test. The results show that both the self-excitation initiating and the speed-rising processes of the generator set have changed synchronously thus to reduce the time needed for MVDC multiphase synchronous generator-rectifier system to start and finish establishing the nominal DC voltage.

Analysis and modeling of novel brushless exciter based on hybrid excitation topology

“…The first is that the excitation power is supplied by a pilot exciter. The shortcoming is that it will increase the total axial length of the unit [3]. The second is that the excitation power is fed by the output of the main generator (MG) through transformers [4], as shown in Fig.…”