Power Plants Relay Setting Calculation Microcomputer

Power system is consist of generating equipment, transiting equipment, distributing equipment and consumers. Power system has a close relationship with industry and living of human been, so it' s very important to guarantee the steady running of power system. When power grid suffers faults such as short circuit or disconnect of line, the corresponding measures should be taken to get the grid back to steady state. Relay, which equipped in power grid, is one of the most important measures.When the grid suffers a short circuit fault, the relays in the grid, which have cooperate relation, find the element that the fault locates in, and insulate this element from the grid rapidly. So the rest grid can steadily run. To guarantee the relays in the grid can work correctly, how to cooperate among these relays must accord with the correlative rule. So the relay setting should be computed correctly.Relay setting is done by human before, which costs a lot of time and is easy to incur computing misplay. With the development of computer and its language, relay setting based on computer has a great progress. Relay settings of electric power plant include generator, plant transformer, electromotor and distributing net relay setting. The generator and plant transformer relay setting realize easier with mightiness function and exploitation of EXCE1, because they have invariable math model and the equipment parameter is not alternate. As regards distributing net, the running mode and equipment parameter is different, the setting and correspondent is also different, and it involved ring system, so it is mainly for studying to aim at distributing net relay setting. In this paper, a three-step current protection program, which is suit for distributing net, is written with C++. In this program, the ring-system of power grid can be found and unblocked, and both manual and automatic relay setting are available. To validate the correctness of the program, the relay setting of a power system adapted from a real distributing net is done, the result is satisfying.