Study on novel fuzzy controller and its application in PWM inverters

With the development of power electronics, PWM inverters become more and more important and gain more and more wide applications. PWM inverters are common parts of a lot of power electronic devices and their controller design is very important for working performance. In order to better adapt the nonlinearity and uncertainty of power system, and absorb the advantages of conventional PI controller and fuzzy controller and conquer their disadvantages, this paper proposes a novel fuzzy self adjustable PI controller. In this novel controller, the parameters of PI controller are dynamically adjusted by fuzzy self adjustable controller, so the high steady-state precision and fast dynamic responding speed can all be obtained at the same time. The novel controller designed in this paper has simple structure and is very convenient to be realized in digital control system, which improves the practicability of the proposed controller. Finally, the proposed controller is applied into the active power filter device which is composed of PWM inverter. Simulation and experiment results verify the effectiveness and superiority of the proposed controller.