一种用于抑制混合动力电驱系统母线电压泵升的前馈补偿控制策略

摘要

In the hybrid AC-DC-AC electric drive system of engineering equipment,the PMSM usually regenerates excessive braking energy to the D.C bus during the regenerated braking process.The excessive energy is likely to cause the D.C bus voltage pumping and reduces the operating performance of engine.To solve this problem,this paper analyzes the reason of D.C bus voltage pumping in the braking process from the view of the non-coincidence of the DC/DC and the inverter.On this basis,a control strategy of a feed-forward compensation added to the FOC outer loop is proposed.This strategy uses the PD controller to deal with the error between the D.C bus voltage and its reference value,and then adds the outputs of PD controller to the reference of iq,so that the iq and the duty cycle of inverter can be both reduced.The regenerated power of PMSM is also limited.The simulation results show that the proposed control strategy can effectively improve the problem of D.C bus voltage pumping during the PMSM regenerated braking process,which is good for the electrical safety protecting in the D.C bus.%在应用于工程装备的混合动力交直交电驱系统中,永磁同步电机在进行再生制动时往往回馈过量的电功率至直流母线上,容易引起直流母线电压泵升,影响发动/发电机组的运行性能.为解决该问题,从电机制动时逆变器和储能系统双向DC/DC占空比匹配不一致的角度分析母线电压泵升的原因,在此基础上提出了一种在传统逆变器双闭环矢量控制的转速外环上添加前馈补偿的控制策略,通过将直流母线电压与其参考值的误差进行比例-微分调节,并利用其输出的补偿量作为下垂因子作用于q轴电流给定值上,减小电机制动阶段的转矩电流和逆变器的占空比,限制电机回馈的电功率.仿真结果表明,该控制策略能有效改善混合动力电驱系统电机制动阶段母线电压泵升的问题,能较好地保护母线电气安全.