Determination of distributed generation capacity from a voltage regulation perspective

The Voltage-Power (V-P) relationship at the Point of Common Connection (PCC) of Distributed Generators (DG) identifies the overvoltage condition due to DG connections. However, overvoltages are not the only consideration. In the connection of DG in distribution and subtransmission feeders voltage fluctuation and instability are also important issues. This paper provides a systematic analysis of the voltage regulation issue, presents a practical and conservative approach to maximize the DG capacity of a Transformer Station (TS) and to minimize voltage fluctuation while keeping the feeder voltage within an acceptable range, with minimum modification to existing voltage regulating facilities. The approach not only takes into account voltage performance at the PCCs, but also at the TS bus, therefore the entire TS.