The Electromagnetic Design Of Brushless Doubly-fed Machine As Generator And The Analysis Of Performance

In this paper, first, the fundamental principle of operation of Brushless Doubly-Fed Machine(BDFM) has been introduced, and then the steady-state equivalent circuit of BDFM was utilised to propose the basic idea of design and give the arithmetic flow chart of BDFM as generator. As calculation of parameters for a variety of different machines is required, the approach of calculating leakage inductance due to slot and harmonic presented here for wound rotor is motivated by versatility.The primary work of this paper was taken advantage of Vc++6.0 to compile an electromagnetic calculation program that was interfaced and easy to operate.Through the size of slot and the proposal of wound design that was given,the program can calculate all kinds of performance such as the ultimate loaded capability under one specific rotate speed,the voltage and current value of the control winding,the distribution of power,the efficiency of BDFM as generator,the current density and the root-mean-square of the two funadamental flux densities.In this paper,the wound rotor was adopted for the BDFM, the nested loop rotor and the ALA rotor were not involved.At last,the paper takes an 4/8 poles BDFM as generator for instance and gives the performance data that was calculated by the program.The paper also analyzes and compares the data with the measurement in experiment.