RENEWABLE SOURCES DIRECT CURRENT ELECTRIC ENERGY SWITCHING TO THE THREE-PHASE AC NETWORK METHOD AND DEVICE Russian patent published in 2018 - IPC H02J3/38 

FIELD: power engineering.

SUBSTANCE: use in the field of electric power engineering. Method of the renewable sources direct current electric energy switching to the three-phase AC network includes the DC supply current filtering, renewable DC power source energy conversion into the AC electric power by means of the autonomous inverter, matching the obtained alternating current with the AC network in frequency and voltage and power transmission to the network. Autonomous inverter output voltage is filtered by each phase, stepping up by means of transformer, stepped up voltage is filtered, transmit to the connected to the three-phase alternating current network output switch. Information on the direct current and voltage values and on the stepped up filtered AC current and the AC mains voltage instantaneous phase values are transmitted to the control device, comparing the obtained information, generating control actions for the pulse-width modulator, generating control signals for the autonomous inverter keys driver, synchronizing the transformer output with the alternating current network, turning on the transformer and AC network into the parallel operation by closing the output switch, reducing the asymmetry and equalizing current in the neutral and performing the renewable energy sources electrical energy transmission to the AC network.

EFFECT: reduction of the three-phase alternating current asymmetry during the renewable energy sources converted DC energy transmission to the network and eliminating possibility of the inverter protective shutdown or failure due to the network phase voltages instability and large equalizing phase currents and current in the neutral occurrence.

2 cl, 2 dwg