Power System Voltage Stability Based On The Sub-control Study

Voltage stability is very important for the electricity to keep it being economical and stable。 Hold the voltage in the set area and avoid voltage collapse is an essential measure for the system to run in an acceptable manner. Now which is extensively used by the electric system in Europe is the tertiary voltage control mode. It is an effective way to control the voltage level. Recently a lot of scholars apply themselves to the research of voltage control. This paper is mainly do some research on the secondary voltage control, and brings forward some points.The characteristic of secondary voltage control is sub area. First of all divide the power system into several sub areas in which the buses is coupled closely, and then select the bus that can represent the voltage level of the all buses in this area as the pilot bus. The pilot bus can control the reactive equipment to provide reactive power when it is need, by this way to control the voltage of the other buses in sub area.This paper ameliorates the dynamic a measure of secondary control. And present a way to set the number of sub areas. As the state of the system is very important for the sub area, and in the different system state we can get different control areas, so this paper suggests that choose the state nearby the voltage collapse can control the bus voltage more efficiently.