Assessment of medium voltage distribution feeders under high penetration of PV generation

With an increasing number of PV penetrations at the distribution system, the impact on the distribution system is no longer negligible. The complexity of impact assessment comes from the increasing installation capacities and variety of control of PV generators as well. Steady state models are developed for PV plants working on three different reactive power modes in this paper. To assess the impact of PV injection at different capacities, different locations and different operation modes on system voltage profile and power loss, sensitivity indices for system voltage variation and system power loss increase over active power injected by solar generators are proposed separately. The accuracy of these sensitivity indices are proven by calculation results from MATLAB and simulation results from PSS/E of a 12kV distribution system.