High frequency spectral components in distribution voltages and currents due to photovoltaic resources

Abstract

A project on high penetration of solar photovoltaic resources in a power distribution system is described. The photovoltaic resources energize pulse width modulated inverters to interface with the 60 Hz distribution system. The inverter currents have high frequency components (these are not `harmonics', but they are artifacts of the pulse width modulation and generally they are in the 2.0 kHz range and higher). Residential (i.e., `roof top') PV resources are generally relegated to the 5 kW range or less, while `utility scale' PV in the range of 400 kW or more has been used. Modeling of the distribution feeder appropriate for high frequency studies is discussed and simulation results from high frequency power flow are presented. The distribution system is an actual system in the Western United States, and instrumented measurements are available.