Real-time coordinated control of voltage regulation devices in a high PV penetrated weak distribution network

In the weak distribution network, on-load tap-changer (OLTC) needs to operate frequently to regulate the voltage fluctuations. Substantial solar photovoltaic (SPV) penetration affects OLTC life, which leads to increased maintenance cost. On the other hand, battery energy storage sys-tems (BESS) are the most appropriate solution. However, frequent charging/discharging affects the BESS's life and make it uneconomic. Authors have proposed a control to efficiently utilize the existing voltage regulation devices without new communication channels. The proposed algo-rithm utilizing a real-time phasor-measurement unit (PMU) data to coordinate BESS, OLTC, and SPV inverters for the optimal control. In addition, for further improvement, the bidirectional state of charge (SOC) regulation method is also proposed. It further optimizes the existing solution to bring back SOC faster to the reference level to make it available for coming contingencies. Quantitatively, BESS processed energy and OLTC tapping operation have been reduced by 81.9% and 52.9%, respectively.