提出一种滞环斩波PWM控制和时间阀值比较相结合的开关磁阻电机特征位置估计方法。在电机驱动运行中,导通相采用滞环斩波控制,滞环斩波PWM开通时间随相电感增大而增大,当转子到达极对极对齐的特征位置时开始减小,所以通过比较相邻两个滞环斩波PWM开通时间的大小,即可得到特征位置的位置检索脉冲信号。在电机刚开通时刻,相电流从零上升到斩波上限,第一个滞环斩波PWM开通时间比其后面相邻的滞环斩波PWM开通时间长,因此在开通角位置也产生一个位置检索脉冲,但该位置检索脉冲信号是随着开通角变化而变化,不能作为位置估计的基准,为此,用了时间阀值比较的方法,除去该位置检索脉冲信号。由于算法中各估计相是相互独立的,所以该算法具有缺相容错运行性能。实验验证了算法的可行性和正确性。
A feature position estimation method for switched reluctance motor was presented, utilizing hys-teresis chopping control and time threshold comparison. At motor drive, the hysteresis chopping control was carried out in the excited region, the hysteresis chopping open-time rose gradually, at the feature po-sition of the aligned position, the hysteresis chopping open-time dwindle suddenly. The position index pulse was estimated for the aligned position by comparing the adjoining hysteresis chopping open-time. At turn-on angle position, the phase current rose to hysteresis chopping upper limit from zero, the first hys-teresis chopping open-time by longer than the second hysteresis chopping open-time, and the position in-dex pulse was obtained, but the position index pulse changed along with turn-on angle,so the position in-dex pulse of the turn-on angle position must be eliminated for the feature position estimation, and the method of the time threshold comparing was presented. For position estimation phase independence, the fault-tolerant was enhanced, the experiment results demonstrate the feasibility and the validity.