ABSTRACT
Volt/VAr Optimization (VVO) relates to the control of distribution substation and feeder voltage regulation equipment and capacitor banks with two main objectives: reducing VAr flow on the distribution system and adjusting voltage at the customer revenue meter delivery point within required limits. This chapter provides discussions that reference the voltage levels and operation of the US electrical system as an example. To regulate the voltage levels at the substation and along the distribution feeder and ensure that the voltage levels are within limits at the customer revenue meter, substation power transformers and distribution feeder voltage transformers are equipped with means to change the turns ratio of the transformer while energized. The tap changing equipment on power transformers are referred to as LTCs. When regulating the voltage on the primary side of the distribution system, the utility will use a combination of regulators/LTCs and switched capacitor banks. The chapter discusses three different approaches: local intelligence, advanced metering infrastructures-based centralized, and model-based centralized.
