Calculation method of distributed power generation and traditional power plant short-circuit current based on interval operation

Abstract

The invention discloses a short circuit current calculation method for a distributed type power supply and a conventional power plant based on interval arithmetic. The short circuit current calculation method comprises the following steps of (1) inputting electrical parameters corresponding to power plant equipment, and superior-level and current-level bus node numbers connected with each electrical parameter; (2) examining whether each electrical parameter is complete or not, if not, prompting to perform manual correction, and if so, performing a step (3); (3) converting a per-unit value of each electrical parameter; (4) establishing index pointers of the current-level and the superior-level bus node numbers; (5) determining maximum and minimum operating modes of each terminal, and taking system impedances under the maximum and minimum operating modes as interval numbers to be processed; (6) searching longest and shortest paths; (7) if path searching in the step (6) cannot be completed, determining that an island exists, and turning to perform the step (2), or otherwise, performing a step (8); and (8), calculating the short circuit current. The short circuit current calculation method is less in input parameters, and only equipment types and the parameters related to the short circuit currents are required to be input in an excel form, so that the workload is reduced.

Description

technical field

[0001] The invention relates to a method for calculating the short-circuit current of a distributed power supply and a traditional power plant based on interval calculation, and belongs to the technical field of setting calculation of relay protection of a power system. Background technique

[0002] Short-circuit faults are serious faults in power plants. Due to the different types of short-circuits, places of occurrence and duration, the consequences of short-circuit currents may only destroy local plant power supply, or may threaten the entire power plant or even cause damage to the safe and stable operation of the power grid. influences. With the increasing capacity of units in power plants, at present, units with "large capacity, high efficiency, and low emissions" have become the mainstream mode of power plants, and the corresponding auxiliary machines such as electric motors and electric pumps in power plants have also increased by orders of magnitude. ...

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