| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To detect a decrease in voltage caused by reactive power characteristics with high sensitivity and no incorrect decision even if the system busbar is an electric power system connected by network electric feeder line while protective operation is actualized adequately. <P>SOLUTION: A master device, which acquires system electrical quantity of one or more high-order substations, detects a voltage drop resulting from the reactive power characteristics of the electric power system and transmits a detection signal of voltage decrease to a terminal device, which acquires the system electrical quantity of one or more low-order substations. Based on a load voltage and a load current of the load busbar, each terminal device disconnects sequentially a load in order of magnitude of voltage-drop influence resulting from the reactive power characteristics, and thereby the voltage drop caused by reactive power characteristics in power system can be prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
