Comparative Evaluation of Grid Connected Current Source and Voltage Source Inverters for Wind Turbines

Voltage source inverters (VSIs) are currently the predominant inverters in power systems. In the context of renewable energy, grid connected VSIs are designed with LC filter to minimize inductive components. However, the remaining inductors still constitute a significant portion of the system's size and cost. In contrast, current source inverters (CSIs) employ a C filter, reducing the number of filter inductors but necessitating an inductor on the DC link. To perform an economic evaluation, it is essential to compare the inductive energy storage of VSIs and CSIs. This paper presents a comparison of system configurations, control schemes, inductance energy, and dynamic performance between VSIs and CSIs, using a 5 MW wind turbine as an example. The study demonstrates that CSIs are economically viable, and may even be superior, for this application.