A High Voltage Gain Quasi-Switched Boost Impedance Network For Renewable Energy Applications

A novel impedance source network has been proposed in this paper for high step up renewable applications in two different configuration. The proposed network has been derived after examining the Quasi Switched Boost (QSB) impedance network, and introduces two times higher voltage gain than the QSB. The steady state analysis of the impedance network, parameter design, PWM control strategy and comparison with some popular existing topologies have been investigated. The proposed converter has all the desired features of the Quasi Z-Source and Quasi Switched Boost converter, like low input current ripple, common ground and low capacitor voltage stress. The classical AC small signal modeling has been done to understand dynamical behaviour of the proposed network. The deduced transfer functions from AC small signal analysis have shown the presence of Right Half Plane (RHP) zeroes, which make the proposed network a non minimum phase system. Further, the effect of the RHP zeroes on the control dynamics has been studied through the variations of parameters. Computer simulation results have been provided to validate the dynamical model of the proposed network. Experimental results on a scaled-down lab prototype are carried out to verify the fundamental steady state theory.