Analysis on evolution of reactive power and voltage control methods

The inner relationship of different reactive power and voltage control methods is the research emphasis of this paper. An ideal optimal control method was modified to produce several practical control methods by simplifications on time, space, and objective. Discussion and classification on the three dimensions of time, space, and objective are carried out. Mathematical models are presented for an ideal control method, a two-level control method, an optimization-holding control method, and a three-level control method. Conclusions are drawn lastly on the evolution relationship of these control methods, which are different degenerate forms of the ideal model and designed for different work conditions respectively. The three-level control method is shown to be more suitable for power networks at the present in China.