三级式同步电机单相交流励磁死区补偿方法

Dead-time compensation method of single-phase AC excitation for three-stage brushless synchronous machines

采用一种三参数正弦曲线拟合的方法,通过实时拟合电流采样值所在的正弦曲线修正当前的电流采样值,以获取励磁电流的极性,实现死区补偿。同时,采用移动窗迭代法对三参数正弦曲线拟合的计算过程进行优化。研究结果表明:结合移动窗迭代方法,三参数正弦拟合法能够较好地实现在电流畸变情况下的电流极性判断,解决三级式同步电机在单相交流励磁时的死区补偿问题。

A method was proposed to acquire the distorted one-phase excitation alternating current directions of the exciter in the starting mode of three-stage brushless synchronous starter/generator system for the dead-time compensation of the single-phase H bridge inverter. A three-parameter sine wave curve-fit algorithm which can fit sin waves in real time using the present sample current was adopted. Thus, the present sample current could be modified and current directions could be determined. Meanwhile, the sliding-window iterative algorithm was used to reduce the calculation amount of three-parameter sine wave curve-fit method. The results show that the three-parameter sine wave curve-fit algorithm optimized by sliding-window iterative method can estimate current directions well when the excitation current of the exciter is distorted seriously. Thus, the dead-time compensation of the single-phase H bridge inverter can be realized in the starting mode of three-stage brushless synchronous starter/generator system with the exciter excited by one-phase AC.