基于磁链函数的无刷直流电机(BLDCM)换相策略对电流噪声极为敏感，尤其在低速时，磁链函数值会产生巨大波动，导致换相超前甚至误换相的发生。通过理论分析得出函数值波动的内在机理，并且使用含有积分结构的磁链函数达到减小函数值波动的目的。另外，为了消除纯积分带来的零漂和初值误差的影响，将积分器替换成带通滤波器，并通过动态调节中心频率，获得准确的换相时间点。同时，采用一种新型的换相判断机制，减小由数值波动产生的影响，提高换相时刻判断的准确性和可靠性。数值仿真结果表明，基于改进的换相策略能够在低速、电流噪声干扰的条件下，获得准确可靠的换相信号，保证电机稳定运行。

The commutation strategy for brushless DC motor (BLDCM) based on flux-linkage function is extremely sensitive to current noise. Especially, the values of function fluctuate greatly at low speeds, resulting in commutation lead or even mis-commutation. In order to suppress the fluctuation, a flux-linkage function with an integrator is implemented after a deep analysis of fluctuation mechanism. In addition, for eliminating the effect of zero drift and integral initial error, a structure is designed by replacing the integrator with a band pass filter. Meanwhile, an accurate commutation point can be obtained by adjusting the center frequency of the filter dynamically. Furthermore, a novel method for identification of commutation point is proposed. The effect of the fluctuation is reduced, and the accuracy and reliability of the commutation point are improved. Simulation results show that the proposed strategy based on the new flux-linkage function can obtain accurate and reliable commutation signal under the comprehensive constraints of low speed and current noise, which can ensure the stable operation of BLDCM.

国家自然科学基金项目（61963006,61563006）;广西自然科学基金项（2018GXNSFAA294085，2018GXNSFAA050029,2014GXNSFBA118284）；广西高校中青年教师科研基础能力提升项目（KY2016YB244）