Graduate School of International Studies Ajou University
Review of several professional and scholarly sources reveal an increasing trend for many electric utilities to seek greater improvements in the reliability and power quality on the distribution network. Such improvements are required to meet the dynamic needs of modern consumers, as well as to facilitate integration of more dynamic elements on the grid such as distributed generation like rooftop solar PV. Also taken into consideration, are the concerns of the utility regulators, who set targets for these parameters (power quality and reliability) and incentivise compliance for the benefit of the industry.
A cost-effective approach implemented by these utilities has been the installation of automation and control devices and software. To date, the installation of these systems has proven to be very useful in improving the quality of the power output on the distribution system compared to its basic state while enhancing its ability to operate on its own acting as the local control.
However, analyses conducted in the present study reveal that the local control presents less optimal results in meeting the primary objectives of 1) improving the average voltage on the distribution system to approximately 1 P.U, 2) decreasing the number of violations recorded on the system and 3) minimizing power loss. This deficiency of the local control was determined by simulating a typical distribution feeder, a modified IEEE 123 feeder circuit, and considering the effects of incorporating solar PV generation on the circuit.
This paper proposes a hierarchical coordinate control approach to improving the performance of a distribution feeder circuit with and without integrated photovoltaic (PV) generation. The control devices considered are the on-load tap (OLTC) transformer, Shunt capacitors and Voltage regulators. The simulation results indicate that the use of hierarchical coordinate control is preferable to basic local control methodology for improving the overall average voltage, reducing violations as well as reducing power losses on the network.