Sliding mode control of the nonminimum phase grid-connected Z-source inverter

Abstract

Summary It is well known that linear controllers are designed by using small‐signal approximation around a certain operating point that cannot guarantee the stability of a nonlinear system in a wide operating range. In this paper, a hyperplane sliding mode controller (SMC) is proposed for voltage regulation across the direct current side capacitor in a single‐phase grid‐connected Z‐source inverter. Considering nonminimum phase characteristics of the converter, capacitor voltage is indirectly controlled by regulation of current through the DC‐side inductor. Moreover, another SMC is designed to control AC‐side output current. The SMCs are developed by using an exact nonlinear state‐space averaged model of Z‐source inverter, and hence, stability and robustness of the system are maintained along a wide range of operation. It is shown that the proposed SMCs have zero steady‐state error and acceptable dynamic response. Some simulations are performed in MATLAB/Simulink toolbox to verify the effectiveness and accuracy of the developed controllers. Practical response of the designed grid‐connected Z‐source inverter is demonstrated by using a TMS320F28335 digital signal processor in comparison with conventional linear controllers.

DC‐link voltage control strategy of Z‐source inverter for high‐speed permanent magnet motor

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Continuous finite‐time control of four‐leg inverter through fast terminal sliding mode control

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