Terminal Voltage Oriented Control of Excitation Winding for New AC-Excited Hybrid Excitation Generator

Hybrid excitation synchronous generator(HESG) inherits the high power density and high efficiency of permanent magnet synchronous machine(PMSM), and solves the problem that the air gap magnetic field of PM machine is difficult to adjust. Because the excitation winding is added to the HESG, its control system has the characteristics of strong coupling, multi-dimensional and multi variable, so it is difficult to control. Firstly, this paper establishes the mathematical model of AC excited HESG and analyses the magnetic regulation mechanism. In addition, a voltage regulation control strategy for the AC-excited HESG is proposed based on terminal voltage oriented control of excitation winding, which realize the stable voltage output when the generator load or speed changes. At the same time, the control strategy effectively eliminates the cross coupling on the d-q channel of the excitation winding. Finally, experimental results verify the accuracy of the mathematical model and the effectiveness of the control strategy.

I. Introduction

The HESG is proposed to solve the problems that the air gap magnetic field and fault de-excitation of permanent magnet synchronous machine is difficult to adjust^[1]. At the same time, the HESG has higher power density and efficiency than the electrical excited synchronous machine(EESM). Therefore, it has a wide application prospect in aerospace, ship propulsion, electric vehicles and other independent power systems^[2]–[3].