The presented topology in this paper represents a boosting topology known as extended boost active switch-controlled switched inductor Z-source inverter (EBASCSI-ZSI). The presented topology has the ability to provide high boost output voltage with lower shoot-through duty cycle. Three existing topologies in the field of Z-source inverter, namely, qZSI, DA-qZSI, and CA-qZSI, have been compared with the presented topology. It has been found that the boosting factor of the presented topology is higher compared to the three topologies. The presented topology has used the same number of inductors and a less capacitor compared to CA-qZSI topology, the same number of inductors and capacitors as compared to DA-qZSI topology, a more capacitor, and an inductor compared to qZSI topology. The voltage stress across the capacitors of the presented topology is approximately the same compared to CA-qZSI topology at higher shoot-through state, and the voltage stress is more compared to DA-qZSI and qZSI topologies at the same shoot-through state. The current stress across the inductors of the presented topology is similar across some inductors of the DA-qZSI and CA-qZSI topologies while in some other inductors, it is lower than that of CA-qZSI topology. The presented topology has been designed with a common ground between the source and inverter bridge while drawing continuous current from the source. The simulation model and its hardware prototype have been developed in the laboratory. The theoretical formulae obtained from the proposed model are matching with outcome of the simulation and hardware model.

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This paper presents a control scheme for single phase grid connected photovoltaic (PV) system operating under both grid connected and isolated grid mode. The control techniques include voltage and current control of grid-tie PV inverter. During grid connected mode, grid controls the amplitude and frequency of the PV inverter output voltage, and the inverter operates in a current controlled mode. The current controller for grid connected mode fulfills two requirements -namely, (i) during light load condition the excess energy generated from the PV inverter is fed to the grid and (ii) during an overload condition or in case of unfavorable atmospheric conditions the load demand is met by both PV inverter and the grid. In order to synchronize the PV inverter with the grid a dual transport delay based phase locked loop (PLL) is used. On the other hand, during isolated grid operation the PV inverter operates in voltage-controlled mode to maintain a constant amplitude and frequency of the voltage across the load. For the optimum use of the PV module, a modified P&O based maximum power point tracking (MPPT) controller is used which enables the maximum power extraction under varying irradiation and temperature conditions. The validity of the proposed system is verified through simulation as well as hardware implementation.

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This post provides a uniform system of power quality control strategy. This control strategy is in 3-phase and 3-wire system. The device combines a UPQC, shunt active filter with an active series filters in the back to back configuration. UPQC designed for simultaneous compensation of current and voltage harmonics. This paper focus on simple control strategy with voltage sag-swell/harmonic/flicker compensation, fuzzy controller benefits over PI controller. Simulation results based on SIMPOWERSYSTEM by MATLAB / Simulink are presented, and verified the effectiveness of the proposed control technology.