基于一种新的变结构控制思想的开关型正弦电压源

摘要

The classic way for the synthesis of a sinusoidal voltage is the PWM with PID controller in relation to a reference sinusoid,which have poor robustness. Based on it,the sliding mode control is applied to improve robustness against load variations and the primary source disturbance. Because the controller is fed directly by the state variables,instead of the error variables ,the structure is simplified. The notes proposed the employment of a nonlinear surface and the reaching condition is derived. Simulation results confirm the validity of the scheme and it also shows that this method endows the system with quite fast convergence as well as strong robustness. This method can be well applied for its simple structure and little calculating time.%传统的开关型正弦电压源采用的是PWM技术与PID控制相结合的方法，它是对参考正弦信号的跟踪控制，鲁棒性较差。本文针对这类开关型的正弦电压源，使用变结构控制策略，提高了正弦电压源对负载的鲁棒性和对自身参数摄动的抗干扰性。同时，由于直接使用状态变量作为反馈量，无需参考信号。在变结构控制思想中，抛弃了经典的线性切换面，使用一种椭圆形的非线性切换面，并推导了相应的控制律和切换面的到达条件。仿真结果证实了理论的正确性，同时还表明，该方法除具有较好的鲁棒性能外，快速性也较好。简单的结构和相当小的计算量使该方法应用前景看好。