Use of multifield induction machine to determine the characteristics of self‐excited generator systems at variable speed, constant voltage and constant frequency

Abstract

This paper considers a generator system using variable energy such as wind power. The variable energy influences the voltage and frequency of a generator system. However, the load requires constant voltage and frequency. Therefore, this paper proposed that a generator system have the following good points: This generator is a brushless system which makes use of the multifield induction machine; Frequency converter of small capacity which is used for constant voltage and frequency in load at variable speed; The PWM inverter can supply reactive power to the self‐excited generator; and Voltage wave of load is sine wave by LC filter of the frequency converter. The multifield induction machines of this generator system have 4 poles and 8 poles similar to stator winding. The rotor of the multifield machine is especially cage type. This rotor can transform among the 4‐pole field and 8‐pole field on the stator. In this paper, an experimental study of the brushless, self‐excited, constant voltage, constant frequency, variable speed and sine wave generator system by multifield induction machine is described. The component of this generator system, operation of multifield induction machine, characteristics of generator system, and the effect of LC filter in frequency converter are described.