基于比例重复的T型三电平并网变换器控制研究

摘要

在详细分析T型三电平变换器工作机理与数学模型的基础上,针对传统PI控制策略难以满足系统高性能指标的要求,同时准比例谐振控制系统设计过于繁琐,设计并采用了引入电压前馈解耦的比例重复复合电流内环控制策略,给出了详细的理论分析与环路参数设计方案.同时,为进一步验证文中策略的有效性,构建了完整的仿真模型并进行了必要的实验验证,结果表明,文中控制策略性能良好,输入电流THD得到显著改善,便于数字化实现,系统动静态特性优良.%The work mechanism and mathematical model of T-type three level converters were detail analyzed,in view of that the traditional PI control strategy can not meets the requirement of system high-performance index,at the same time,and proportion of quasi resonant design of control system is too cumbersome. The control strategy named proportion and repetitive compound strategy with voltage feed-forward decoupling was adopted in the current inner loop to achieve the interconnection of the rectifier unit power factor control. The detailed theoretical analysis and design were given. To test and verify the feasibility of the control strategy ,a complete system simulation model and experimental platform were built,the results show that the design and the control strategy can effectively improve the system performance,the input current THD get improved significantly,the control strategy is simple and easy digital realization,the system dynamic and static characteristics are good.