为了减小网侧谐波电流,改善电能质量,提出N脉波变拓扑相控整流器(FTTR)的一般结构形式,并对工作模式、拓扑切换策略及拓扑切换的过渡过程进行分析,在此基础上利用平均值电流预测控制算法计算晶闸管触发时刻,实现快速的电流动态响应.鉴于预测控制算法对电感参数变化敏感的问题,提出应用最小二乘法在线校正电感参数,消除模型参数变化引起的电流稳态误差.以24脉波FTTR为研究对象进行仿真和实验分析,仿真和实验结果验证了N脉波FTTR的可行性以及电流预测控制算法的有效性.
A general structure of the N-pulse flexible-topology thyristor rectifier(FTTR)was proposed in order to mitigate the harmonic-current injection and improve the power quality.Then its operating mode and topology-switching strategy as well as transient performance were discussed.The predictive averagecurrent control algorithm was presented to calculate the firing instance and thereby achieve the fast current response.As the predictive average-current control method is sensitive to the variation of the inductance value,the least square method(LSM)was employed to execute an on-line parameter correction of the inductor and eliminate the steady-state error of the inductor current.A simulation model and its corresponding experimental prototype based on a 24-pulse FTTR were developed.Simulation and experimental results showed the feasibility of the proposed N-pulse FTTR and the effectiveness of the current control method.