基于过调制策略的电静液作动器交流电机弱磁区动态性能优化研究OA

Field-Weakening Control technology is the core technology for high-speed driving of electro-hydrostatic actuators(EHA)AC motors.The voltage closed-loop field weakening control system achieves optimal allocation of voltage and current,enabling maximum torque output across the entire speed range.However,in practical operation,issues such as low utilization of the DC bus voltage and voltage saturation inevitably arise.To further enhance the torque output capability and improve the dynamic performance of the EHA AC motor drive system,based on the fundamental voltage amplitude-invariant hexagon voltage extension principle,this paper proposes a sector-based overmodulation strategy.This overmodulation strategy divides the AC motor's operation into the linear region,overmodulation mode Ⅰ,and overmodulation mode Ⅱ.By adjusting the amplitude and phase of the output voltage vector,the voltage waste phenomenon is eliminated,and the voltage is expanded from the inscribed circle voltage to the hexagonal voltage,and then to the six-step voltage.Finally,experimental comparisons are conducted to verify the effectiveness of the proposed method.The proposed strategy optimizes the voltage vector trajectory,enhances DC bus voltage utilization ratio,expands the maximum output torque capability in the high-speed field-weakening region,and ultimately improves the dynamic performance of the AC motor drive system in electrostatic hydrostatic actuators during field-weakening operation.