【作者】 史文婷； 李洁； 李向龙；

【Author】 Shi Wen-Ting;Li Jie;Li Xiang-Long;School of Automation and Information Engineering Xi’an University of Technology;

【机构】 西安理工大学自动化与信息工程学院；

【摘要】 为了提高三相电压型PWM整流器的响应速度、提高控制器对交流侧电感参数的鲁棒性、降低电网电压不平衡时的输入电流THD,提出一种改进的无差拍预测控制方法,同时为了节省成本,省去网侧电压测量元件,将虚拟磁链观测器与所提出的无差拍预测控制进行了结合。引入重复控制器改进了已有的无差拍预测控制算法,对功率进行反馈校正,每一拍都修正其预测给定值以优化功率跟踪性能、消除系统稳态误差、提高系统鲁棒性。在虚拟磁链观测器中引入二阶广义积分器提高了数字积分计算性能,解决了纯积分环节的初值和直流偏置问题。至此,构建了一个完整的无电压传感器无差拍控制方法。与无电压传感器PI控制以及有电压传感器的无差拍直接功率控制进行了仿真对比研究。结果表明,所提出的控制方法提高了系统的鲁棒性,并且在电网电压不平衡的情况下电流谐波畸变率更低。更多还原

【Abstract】 In order to improve the response speed of three-phase voltage source PWM rectifier, improve the robustness of the controller to AC-side inductance parameters and reduce the input current THD when the grid voltage is unbalanced, an improved deadbeat predictive control method is proposed. In order to save cost and eliminate the grid-side voltage measurement elements, a virtual flux observer is proposed. It is combined with the proposed deadbeat predictive control. The repetitive controller is introduced to improve the existing deadbeat predictive control algorithm, and the power is corrected by feedback. Each beat is correct ed to optimize the power tracking performance, eliminate the steady-state error and improve the robustness of the system. A second-order generalized integrator is introduced into the virtual flux observer to improve the performance of digital integration and solve the problem of initial value and DC bias of pure integration. So far, a complete deadbeat control method without voltage sensor has been constructed. The simulation results are compared with PI control without voltage sensor and deadbeat direct po wer control with voltage sensor. The results show that the proposed control method improves the robustness of the system, and the current harmonic distortion rate is lower when the grid voltage is unbalanced.更多还原