Decoupled MultiLoop Control of Switched Inductor Z-Source Inverters for Distributed Generations

Abstract

Switched inductor topology is an advanced byproduct of Z-Source inverter which is equipped with enlarged voltage boost factor capability, employing less duty ratio and high modulation index. A well established closed loop power control requires high quality waveform followed by a good current controller which should be precise and should have significant effect on the dynamics of the system. Transient modelling is performed to widen the investigative study of non-minimum phase behaviour caused by right hand plane zeroes exhibited due to the impedance network on the DC side of these inverters. Also the independency of DC side and AC side control has been kept in discussion with separate controller designs. This paper presents an idea of decoupled AC side control in synchronous reference frame to eliminate the cross coupled behaviour of d-q axes during independent control of active and reactive powers. Simulation result shows good reference tracking and disturbance rejection property, which is recognised to be evident and substantial using MATLAB as testing platform.