Digital-Power-Communication Concept for Energy Coordination in PV-Battery-Charging DC Microgrid

Abstract

A new digital-power-communication (DPC) concept is proposed to better realize information interaction and energy coordination in the PV-battery-charging DC microgrid, which uses the DPC auxiliary power supply as carrier. The DPC auxiliary power supply can be used to replace other communication modules as a common carrier for auxiliary power supply and information interaction of microgrid interface converter. Then, the implementation conditions of DPC are indicated that this communication concept requires active power consumption and an adjustable resonant network. Meanwhile, an appropriate circuit topology of the DPC auxiliary power supply is evolved. Furthermore, an integrated control method of optimal-admittance information regulation & power supply is further proposed for the DPC auxiliary power supply, and the implementation mechanism of this method is analyzed in detail by establishing the admittance model. More importantly, based on this method, the contradiction between power supply quality and signal intensity can be solved in the transmit mode, and the received signal intensity of the communicating node can be significantly enhanced in the receive mode. Finally, the PVbattery-charging DC microgrid platform is developed, and the experiment result verify the feasibility of the DPC concept and the effectiveness of the proposed control method.