The Use of Thyristor-Based Static VAR Compensators to Enhance Distribution System Security

Abstract

Nowadays, FACTS devices are commonly used for voltage regulation and optimal control of operating parameters of power systems. Controllable FACTS devices relying on power electronics can be used to obtain the required characteristic curve not only for power transmission lines, but also for a specific part of the electrical system. This paper reports the results of a study on operating conditions of a realworld distribution system that has a static thyristorbased VAR compensator (SVC) installed to enhance its security. The efficiency of distribution systems and available ranges of their operating conditions largely depend on the placement of compensation devices and the rules governing their capacity. We propose a consistent approach based on graph theory methods to address this issue. The approach involves examining the conditions for nodal voltage stabilization to reduce the total active power loss in the electrical network. The ranges of variation in SVC capacity are identified and appropriate SVC control rules required to ensure the lowest possible total power loss in the network are established.