Improvement of voltage stability by the advanced high side voltage control regulator

An advanced high side voltage control (HSVC) regulator that can improve power system voltage stability by adding supplemental control to conventional generator excitation system control has been developed. This paper describes the principles, characteristics, and advantages of applying advanced HSVC in comparison with a conventional automatic voltage regulator (AVR) or a static VAr compensator. When applying the advanced HSVC, a high side voltage of a step-up transformer can be controlled to a set value and maintained to a higher value than with conventional excitation systems. This advanced HSVC is realized without any feedback signal from the high voltage side of a step-up transformer (i.e., no high-side voltage measurement required). Stable parallel operation among adjacent generators is also possible. In addition, with an adequate phase compensating function added to the advanced HSVC, oscillatory stability can also be improved