Reactive compensation using static VAR compensators-a planning case study using security constrained techniques

Optimal power flow programs have been widely advocated for voltage performance planning. The National Grid Company (NGC), however, has found that they do not yet address the particular problems encountered on its transmission system. The author illustrates the nature of these problems which require the use of security constrained techniques and describes a method which has enabled a practicable minimum compensation investment strategy to be determined. Recently commissioned compensation devices in the area include 180 MVar mechanically switched capacitors (MSCs) at Indian Queens and Mannington and a 150MVar static VAr compensator (SVC) at Exeter. A further stage of reactive compensation planning for this area has been recently completed and two additional 150 MVar SVCs authorised for commissioning in 1992. The author outlines the compensation planning process as a case study