Effects of photovoltaics on distribution system voltage regulation

As grid-integrated photovoltaic (PV) systems become more prevalent, utilities want to determine if, and at what point, PV systems might begin to negatively impact the voltage regulation of their distribution systems. This paper will briefly describe voltage regulation methods in a utility distribution system. It will also take a preliminary look at the distribution impacts of high penetrations of grid-integrated PV systems being installed and operated in a Sacramento Municipal Utility District community. In particular, the issue of excessive service voltage and excessive substation voltage due to the reverse power flow from exporting PV systems will be examined. We will also compare measured data against modeled data.