Implementation of a control strategy for three-phase four-wire VSI parallel connected

This paper approaches the implementation of a control strategy with communication for three-phase four-wire VSI parallel connected, which is based on distributed control. The paper presents details of implementation of one control strategy that employs two loops, one voltage control and one parallelism control, all system is done on instantaneous values and the parallelism control shares only a voltage reference signal among the VISs. The strategy ensures power load shared among the inverters in steady-state and a fast dynamic response during connection or disconnection of VSI and load step. The control system was implemented in a TMS320F28069 DSP and verified in two 2 kVA VSI parallel-connected.