Keywords:
State space, Phase domain, Switched model, Average model
Abstract
In this work, as part of the activities developed in the scope of a R&D+I, the differential equations that express the dynamics of a VSI (Voltage Source Inverter) fed in current, supplied with input and output filters and connected to the network were studied. From well- established concepts of power electronics, the equations that characterize the VSI in the phase domain were defined. In order to overcome the discontinuities, the averaging operator concept was applied, resulting in a smooth model, but without a static operation point. Applying the Park transform to the averaged model in the phase domain, an averaged model in qd coordinates was obtained, which presents simpler equations and provides a static equilibrium point under steady state condition. Using the standard form of the state space, the equations were solved through the trapezoidal integration rule, whose results prove that the models are equivalent, highlighting the average models for requiring a reduced computational burden.
