基于分层控制的模块化多电平变流器模型预测控制方法

Model Predictive Control Method of Modular Multilevel Converter Based on Hierarchical Control

为了解决传统模块化多电平变流器(MMC)控制器参数过多,参数整定复杂且对控制参数敏感,以及已有MMC模型预测控制(MPC)方法计算量过大、实用性不强等问题,提出一种新型MMC模型预测控制方法,通过建立相应代价函数对MMC相电流、桥臂环流和子模块电压进行分层控制,从而大幅度减少计算量。对相电流模型预测控制的误差进行理论分析并提出补偿措施,提高了相电流控制精度。在Matlab/Simulink平台搭建了11电平MMC仿真系统进行仿真验证。结果表明,新型MMC模型预测控制方法单次运算耗时仅为已有模型预测控制方法的0.24%,相电流误差得到有效校正补偿,功率响应时间短且无超调,验证了新型MMC模型预测控制方法具有计算量低、动态响应快、稳态精度高的特性。

In order to solve the problems that the conventional control methods of modular multilevel converter（MMC） need excessive controller parameters, complex parameter tuning, and are sensitive to parameters, however, the existing model predictive control（MPC） method of MMC needs a huge amount of computation and is unpractical, we proposed a novel MPC method, which takes hierarchical control on phase current, circulating current and submodular voltage on the basis of establishing corresponding cost fimctions so as to reduce the amount of calculation. The error of phase current control was analyzed and compensated to enhance the control precision. An eleven-level MMC simulation system was built under Matlab/Simulink environment for simulation verification. The simulation results verify that the theory of~ the error analysis and compensation. The novel MPC method has significantly lower amount of calculation since its time consuming is merely 0.24 percent of the existing MPC method, and it shows good performances in dynam!c response and accuracy of steady tracking.