非正弦供电十五相感应电机磁路计算方法

Magnetic Circuit Calculation of Fifteen-phase Induction Motor With Non-sinusoidal Supply

鉴于电机气隙磁势为非正弦分布磁势,提出分布磁路法对非正弦供电十五相感应电机进行磁路计算并求出激磁电抗。分布磁路法从基波和3次谐波合成磁势出发,在电机半个极范围内进行等间隔周向分块,通过迭代计算得到沿圆周各节点气隙磁密,并由傅里叶分解得到基波和3次谐波磁密。以等值电路为基础同时结合分布磁路法,迭代计算给定电压下基波激磁电抗与3次谐波激磁电抗。对非正弦供电十五相感应电机样机进行空载实验,得到基波激磁电抗与3次谐波激磁电抗实测值。激磁电抗计算值与实测值相互吻合,说明了分布磁路法的有效性和准确性。

In view that the stator and rotor resultant magneto-motive forces （MMF） of the fifteen-phase induction motor under non-sinusoidal supply is of non-sinusoidal distribution, the distributed magnetic circuit method is put forward to perform magnetic circuit calculation and the magnetizing reactances are deduced. Based on fundamental and 3-order harmonic resultant MME the presented method is utilized to divide the half-pole motor model into equi-interval sections with circumferential air-gap node flux densities obtained by iteration and Fourier series decomposed into fundamental and third harmonic ones. The equivalent circuit is combined with the distributed magnetic circuit method to finally determine the fundamental reactance and 3-order harmonic reactance by iterative method under given voltages. To carry out no-load experiments for a sampled fifteen-phase induction motor, the measured fundamental reactances and third harmonic reactances are gained and compared with the calculated ones. The good agreement between calculated reactances and measured ones shows the validity and accuracy of the presented method.