IDENTIFICATION OF LCL FILTER PARAMETERS

A model-based method of estimating physical parameters of a LCL filter connected between a converter and electrical power network and a converter. The method comprising forming an analytical discrete-time model of the LCL filter and the converter, forming a discrete-time pulse-transfer function of the analytical discrete-time model having discrete time parameters, injecting a voltage signal superimposed on the reference voltage to the converter, determining output current of the converter, based on the injected voltage signal and output current of the converter, estimating the discrete-time parameters, and based on the estimated discrete-time parameters solving the estimated physical parameters using the analytical discrete-time model.