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A new dynamic model is developed in this paper to connect PEM Fuel Cell (PEMFC) to a Z-source inverter (ZSI). This model is used to analyse the behaviour of a fuel cell by providing a polarization curve. A controller is designed based on an interpolation to spot parameters of PEM Fuel Cell such as temperature (or anode and cathode pressure). A current feedback is gained to regulate the output voltage through determination of physical parameters. The ZSI is used in the proposed model to generate AC power. In this research, to compensate the voltage drop of fuel cell the capacitor voltage of the Z-network is controlled using the state space averaging method to stabilize the AC output voltage of the ZSI. Simulation and experimental results verify the validity of the proposed controlling model

This paper deals with a new family of high boost voltage inverters called switched-inductor quasi-Z-source inverters (SL-qZSIs). The proposed SL-qZSI is based on the well-known qZSI topology and adds only one inductor and three diodes. In comparison to the SL-ZSI, for the same input and output voltages, the proposed SL-qZSI provides continuous input current, a common ground with the dc source, reduced the passive component count, reduced voltage stress on capacitors, lower shoot-through current, and lower current stress on inductors and diodes. In addition, the proposed SL-qZSI can suppress inrush current at startup, which might destroy the devices. This paper presents the operating principles, analysis, and simulation results, and compares them with those of the SL-ZSI. To verify the performance of the proposed converter, a laboratory prototype was constructed with 48 Vdc input and an ac output line-to-line voltage of 120 Vrms. The simulation and experimental results verified that the converter has high step-up inversion ability.

A Z-source Inverter has been proposed as a new topology in recent years. In this inverter an impedance network is placed between an inverter and a power source which provides both voltage buck and boost capabilities. This paper presents a unipolar hysteresis band current control method for a single phase Z-source inverter with symmetrical and asymmetrical Z-network configuration. The obtainable output current of this method in magnitude is higher than the hysteresis current control used in a traditional inverter. This paper also analyses the performance of the proposed control method under input dc voltage fluctuation and load current transient. Theoretical analysis and MATLAB simulations have been performed to describe and validate the control method.