一种可抑制三次谐波的五相混合式步进电机空间矢量脉宽调制优化控制策略

五相混合式步进电机因其定位精度高、转矩脉动小以及转矩密度高等优点而应用愈加广泛。为进一步减小其运行噪声、提高系统整体效率,本文提出一种可抑制三次谐波的五相混合式步进电机空间矢量脉宽调制(Space vector pulse width modulation,SVPWM)优化控制策略。首先搭建了考虑互感条件下的五相混合式步进电机解耦控制数学模型。在此基础上,采用相邻两大矢量和两中矢量合成混合电压矢量的SVPWM控制策略,并给出了相应的五相混合式步进电机双闭环控制系统。本文所提的混合SVPWM算法通过利用大、中矢量在基波、三次谐波双坐标系对应关系以达到抑制三次谐波的效果,能够有效降低相电流纹波和谐波含量。最后,研制了一套基于FPGA的实验平台,对所提策略与传统滞环算法、大矢量SVPWM算法进行对比研究,重点分析了3种算法对相电流纹波和谐波含量的影响,从而验证了所提算法的正确性和优越性。

Optimal Control Strategy of SVPWM for Five-Phase Hybrid Stepping Motor Suppressing Third Harmonic Wave

Due to its advantages of high positioning accuracy, small torque ripple and high torque density, five-phase hybrid stepping motor has been widely used. In order to further reduce its operation noise and improve the overall efficiency of the system, this paper proposes a space vector pulse width modulation (SVPWM) optimal control strategy of five-phase hybrid stepping motor which can suppress the third harmonic wave. In this paper, the decoupling control model of five-phase hybrid stepping motor considering mutual inductance is established. On this basis, SVPWM control strategy combining two adjacent large vectors and two medium vectors into a mixed voltage vector is adopted, and the corresponding dual-closed-loop control system of five-phase hybrid stepping motor is given. The mixed SVPWM algorithm proposed in this paper can effectively reduce the phase current ripple and harmonic content by using the large and medium vectors in the fundamental wave and the third harmonic coordinate system to suppress the third harmonic. Finally, an experimental platform based on FPGA is developed to compare the proposed strategy with the traditional hysteresis algorithm and the large vector SVPWM algorithm, and analyze the influence of the three algorithms on the phase current ripple and harmonic content, thus verifying the correctness and superiority of the proposed algorithm.