Adaptive Control of a Single-phase Quasi-Z-Source Inverter

ANDRÉS VÁZQUEZ SIEBER; HERNAN HAIMOVICH; MÓNICA ROMERO

Bariloche

Congreso; XV Reunión de Trabajo en Procesamiento de la Información y Control; 2013

Universidad Nacional de Río Negro

Standard control of quasi-Z-source inverters requires two separate objectives: control of the Z-network output voltage (i.e. the DC bus) and inverter bridge control (PWM). Control design aimed at regulating the Z-network output voltage of a single-phase inverter is complicated by the fact that the current drawn from the Z-network by the AC side of the circuit may contain large-signal variations, as opposed to the case of a three-phase inverter. In this context, our main contribution is to identify and analyze closed-loop properties of a previously introduced Z-network output-voltage control law that make it particularly appealing for the single-phase inverter. Specifically, we show that (a) appropriate selection of design parameters for this control law causes all equilibrium points of the averaged model of the Z-network to correspond to the desired DC bus voltage, irrespective of the value of the input voltage or the current drawn from the Z-network, and (b) the linearization of the closed-loop Z-network dynamics about any of the possible equilibrium points has exactly the same eigenvalues. We also provide simulation experiments that illustrate suitable closed-loop behaviour under large-signal perturbations.