基于反电势形状函数法的无刷直流电动机直接转矩控制

采用两相导通模式时通过逆变器开关状态不能确定电压空间矢量,现有方案是通过实时测量3个相电压来解决这一问题,但系统变得复杂;此外现有方案在转矩观测中包含的微分项会降低控制精度,增大计算量,影响系统实时性。针对这两点不足,提出反电势形状函数法,在软件中实现了相电压的实时计算,使转矩观测变得简洁,更易于工程实用。最后给出的仿真与实验结果证明了反电势形状函数法用于无刷直流电机直接转矩控制中的可行性与有效性。

Direct Torque Control of Brushless DC Motor Based on Back Electromotive Force Shape Function Method

The voltage space vector is difficult to be calculated by the inverter switching state in two-phases-conducting mode.The existed system solves the problem by directly measuring three phases voltage but the control system is more complicated.Furthermore,the differential items in torque estimation reduces the control precision and increases calculation tasks,thus control system real time performances are depressed.To overcome these two deficiencies in the existed system,the back electromotive force shape function method is proposed to realize the real time calculation of phase voltage and make the estimation of torque easer.The method enhances the engineering applicability.Finally,the feasibility of the electromotive force shape function method used in brushless DC motor direct torque control is validated by simulation and experimental results.