中文摘要：

具有非换相相电流反馈的无刷直流电机的传统双闭环调速系统,因非理想梯形波反电势和非理想方波相电流存在较大转矩脉动,该文引入正比于瞬时转矩的合成电流变量,并推导出每个扇区下的合成电流与非换相相电流之间的关系式,通过控制所需合成电流的对应非换相相电流,达到抑制转矩脉动的目的。此外,为了减小换相转矩脉动,采用一种基于PWM-on的新型调制方式。该调制方式在换相期间,三相将进行配合调制,通过计算给每一相分配不同的调制占空比,使开通相和关断相的电流变化率相等。所提转矩脉动抑制方法通过相应的Matlab仿真和数字信号处理驱动实验,验证了其可行性和有效性。

英文摘要：

In the traditional double closed-loop speed control system, the Brushless DC Motor with un-commutated phase current feedback has large torque ripple because of the non-ideal trapezoidal wave back EMF and non-ideal square wave phase currents. To overcome this defect, the relational expression between the resultant current and the un-commutated phase current under each sector is derived by introducing the resultant current which is proportional to the instantaneous torque, and then the torque ripple reduction can be achieved by controlling the un-commutated phase current which corresponds to the resultant current. In addition, to reduce the torque ripple in the commutation region, a new modulation method based on PWM-on is adopted. During the commutation region, three phases can be modulated cooperatively. And with this modulation method, the changing rate of currents in the upcoming phase can be controlled equally to that of the outgoing phase by distributing different modulation duty to each phase. Finally, results of Matlab simulations and experiments with DSP are presented to verify the feasibility and effectiveness of the proposed strategy.