POWER SYSTEM VOLT-VAR OPTIMISATION

Volt-VAr Optimisation (VVO) is a process of optimally managing voltage levels and reactive power to achieve more efficient grid operation by reducing system losses, peak demand or energy consumption or a combination of the three as well as improving voltage stability. The concept of Volt-VAr management or control is essential to electrical utilities’ ability to deliver power within appropriate voltage limits so that consumers’ equipment operates properly, and to deliver power at an optimal power factor to minimize losses. Traditional Volt- VAr management technologies have been used by the power industry for over 30 years to reduce line losses and increase grid efficiency. Today those technologies have advanced to include Volt-VAr Optimization (VVO) sensors, equipment and software capable of reducing overall distribution line losses by 2%– 5% through tight control of voltage and current fluctuations.

Advanced VVO techniques with coordinated control schemes using capbanks, reactors, voltage regulators, STATCOMs or SVCs can help improve voltage stability, reduce line losses, peak load demand and energy consumption. Successful implementation of Advanced VVO systems depends on a wide range of factors throughout the power system network including: Load types, feeder and substation automation, SCADA, communication infrastructure, sensors, metering, feeder and bus voltages, transformers, capbanks, reactors, feeder conductor type size and length, location and size of distributed energy resources (solar, wind and battery).

Advanced VVO solutions provide a higher level of visibility into system operating parameters and a greater degree of automated control to maintain and improve voltage stability, optimize energy efficiency and deliver reliable electricity supply. Utilities are facing a dynamic operating landscape, a landscape that wasn’t envisioned when most electrical networks were designed. The increasing penetration of intermittent renewable generation sources, the increasing diversity and variability of loads are driving this volatility. Utilities are also running closer to the operating limits of these systems than ever before, making the ability to optimize within operating parameters extremely important. Successful implementation of advanced VVO schemes requires good knowledge of the technical requirements, technical and financial challenges, benefits and risks.