Comparative analysis between voltage and current source inverters in grid-connected application

The voltage source inverter is mainly used for grid interfacing of distributed generation systems. In order to boost the voltage of a renewable energy source to the required dc voltage level, a dc-dc converter is necessary even though the cost and complexity of the system are increased. Thus, in improving the cost and life expectancy of the power electronic interface, a current source inverter is an alternative which offers short-circuit protection capabilities, implicit voltage boosting and a simple ac-side filter structure. However, it has attracted less research attention since it is purported to have drawbacks in term of high conduction losses and inefficient inductive energy storage on its dc-side. With reference to advantages and disadvantages of both inverter types, this paper presents a comprehensive comparative analysis with respect to the topological and operational features of the inverters. The comparison includes the power circuit, semiconductor constraints, cost, dc input filtering, steady-state, transient performance and power semiconductor losses. The analytical expectations of the systems are verified using MATLAB/ Simulink software package.