Voltage variation analysis of normally closed-loop distribution feeders interconnected with distributed generation sources

Abstract

Normally, closed-loop distribution feeders apply very well to critical customers due to their higher reliability. However, their voltages vary largely, with some even exceeding voltage limits, while distributed generation sources interconnect with them. This work analyzed the voltage variation of a normally closed-loop distribution feeder interconnected with a distributed generation source. First, the model of a sample system involving a normally closed-loop distribution feeder and a distributed generation source was constructed. Second, the maximum allowable capacity of the distributed generation source was evaluated. Finally, the sample system was simulated, and the voltage variations were analyzed based on the simulation results. The interconnection location and operating power factor of a distributed generation source, plus the loading, power factor, and operating condition of a distribution feeder, are the major factors that affect distribution feeder voltage variation. They were all taken into account in this work.