Voltage Uncertainties in the Presence of Photovoltaic Systems
  With the rising demand for solar energy installation, there is a pressing need for utilities to regulate the voltages at the distribution level. In grids with high penetration of photovoltaic (PV) systems, voltage fluctuations can occur at the distribution systems, resulting in inverter tripping and insufficient power to meet the load. We present a linear model for voltage rise versus PV output power. This model can be used to study the effect of increasing PV system capacities on distribution system voltages. It is observed that voltage fluctuations have greater correlation with the location of the PV systems on the grid than with the PV system capacities, i.e., more randomness and disorder in the behavior of voltage occurs with PV systems with larger line impedance. 
Katherine Hughes
cs.SY