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This paper deals with the nonlinear robust PWM control of a DC/AC differential boost inverter based on dynamic feedback linearization, active disturbance rejection, and sliding mode control techniques. The inverter topology consists of two synchronous boost converters linked through a load resistance. The model of each boost converter is put in Brunovski’s canonical form through dynamic feedback linearization, defining an auxiliary input depending on the control variable in an affine mode and a nonlinear disturbance containing endogenous and exogenous variables. Each disturbance is estimated by an extended state observer and compensated through a control law designed for tracking the desired trajectory, according to the active disturbance rejection control technique. Finally, a sliding mode component is designed and added to the previous control law to assure the robustness of the closed loop system against uncertainties due to electric parameters, supply voltage and load resistance deviations, and disturbance estimation errors. Experimental results validate the proposed control methodology.

The paper deals with the control of a quadratic boost converter supplied by low-voltage energy sources, such as photovoltaic panels, fuel cells, or batteries. The control scheme consists of two control loops. A min-type controller governs the inner loop to force the current state of the nominal model to converge in a neighborhood of the equilibrium state. The external loop processes the output tracking error using an integrator, and it allows reconfiguring the converter’s working point by changing the equilibrium state given in the input to the internal loop. This configuration assures both zero tracking error of the output voltage and robustness against load and input voltage variations and converter parameter uncertainties. The stability of the whole system is investigated using the hybrid system framework. The proposed control technique has been tested experimentally in a suitably developed (low-cost) setup, and the results show the effectiveness of the proposed approach.