Starting and Dynamic Performance of A Parallel Field Rotor Type Hybrid Generator with PM Exciter

This paper presents a hybrid generator with a PM(Permanent Magnet) exciter to improve the operating efficiency, dynamic response and emergency starting characteristic. The proposed hybrid generator is designed by the parallel combination of the winding field and the PM field. In the proposed hybrid generator, the PM assistant field can be added to the conventional winding rotor to improve the total efficiency without the complex optimized design. The assistant PM field can supply the enough linkage flux to produce the no-load generation voltage and the starting power for the controller. The controlled field current of the winding part, is used to produce insufficient flux to keep the constant output voltage from the load variation of the generator.Furthermore, the direct field current control scheme using the PM exciter can improve the dynamic performance compare than the indirect field current control structure of the conventional excitation system. In the designed 10kW prototype hybrid generator with PM exciter is tested and compared with the conventional generator, hybrid generator with the winding exciter.