Grid connected VSI with LCL filter — Models and comparison

There are several ways to model three-phase grid connected voltage source inverters (VSI) with LCL filter. Such models often use simplifications like constant DC-link voltage or averaging over a switching period. These simplifications remove transistor switching and DC-link capacitor dynamics from the model. In this paper, a comprehensive modeling of a three-phase VSI, including a LCL filter is described and compared to models using one or more of the simplifications above. A comparison is also made with simulations based on Simulink SimPowerSystem toolbox. Advantages and disadvantages of different models are discussed. All simulations are verified by comparing with experimental results.