Modelling of Charging Control Scheme for QZSI with Battery Topology

Abstract

Quasi Z-source inverter (qZSI) has been proven to be reliable for inverting DC electricity to AC. When compared with conventional two stage DC-AC boost inverter topology, qZSI is a single stage topology which can be simply constructed via connecting a quasi Z-source (qZS) impedance network in series with an H-bridge inverter. This resulted an attractive topology without needing any switching element and resistor in the DC-link. In this paper, the investigation of qZSI with battery topology is extended to regulate its output voltage from a fluctuating DC input source. Through extensive mathematic derivation, a control scheme which comprised of battery current controller, battery management algorithm, and electronic circuit breaker (ECB) algorithm, is proposed to achieve the aforementioned outcome plus ensuring the effectiveness of battery charging and discharging capability as well as prevention of over-charging and over-discharging of the battery according to the DC input voltage level. All theoretical findings are validated with simulation results using Matlab / Simulink software package.