摘要
并网逆变器控制系统的最终目标是实现对参考电流的跟踪,因此需要根据前两个或三个开关周期的情况对参考电流进行前向预测,由于模型电感与实际电感之间的不匹配,导致不同的预测电流控制算法对系统稳定性的影响不同,或者说在系统稳定的前提下不同算法对电感不匹配程度的容忍度不同。本文在对单相并网逆变器控制系统进行稳定性分析的基础上,对比研究了各种传统算法的优缺点,指出了造成其控制效果不同的根本原因,并提出了一种改进型预测电流控制算法,通过将目标电流误差从前两个开关周期电流差改为另一特定形式,减少对中间变量的近似计算,提高算法可靠程度,将系统稳定对电感不匹配的容忍度大大提高,得到比传统方法更好的稳定裕度。最后,通过建立仿真模型和搭建实验平台验证了该新算法的优越性。
The final aim of the control system of grid-connected inverter is to track the reference current. So it is needed to predict the reference current according to the previous two or three switching periods. Due to the mismatch of the model inductance and actual inductance, the impact had on the stability of system for different control algorithms will be different, namely on the premise that the system be stable, different algorithm differs in the tolerance of inductance mismatch. On the basis of analyzing stability of single phase grid-connected inverter control system, advantages and disadvantages of each kind of predictive current control algorithms were compared. The fundamental reason why the control effects differed from each other was indicated. And an improved predictive current control algorithm was proposed that changes the aim of current error from the current difference of previous two periods to a specified one. The proximate calculation of intermediate variable is decreased and the stability of algorithm is improved. The tolerance of inductance dismatch is largely raised. Better stability margin is achieved relative to conventional methods. In the end the superiority is testified through simulation model and experimental platform.
出处
《电工技术学报》
EI
CSCD
北大核心
2010年第7期100-107,共8页
Transactions of China Electrotechnical Society
关键词
预测控制
电流控制
逆变
脉冲宽度调制
参数匹配
Predictive Control
current control
inverters
pulse wide modulation
parameter match
