A short-circuit current suppression method considering unit start-stop and line switching

Abstract

The invention discloses a short-circuit current suppression method considering unit start-stop and line switching. Firstly, the relationship between the admittance matrix and the short-circuit current is deduced by using the relationship between the node admittance matrix and the node impedance matrix and the physical meaning of the node self-impedance Then consider the change of capacitance to ground after the line is cut off and the influence of the switching line and the start-stop unit on the admittance matrix, and obtain the explicit expression of the short-circuit current; The impact of current limiting measures on system power flow, unit output, etc., with the goal of minimizing power generation costs, unit start-up and shutdown, and line switching costs, a mixed integer linear programming method that takes into account explicit short-circuit current constraints is proposed; For the day-ahead scheduling problem of the system, taking into account the short-circuit current constraints, the unit output arrangement and line switching are comprehensively optimized, and the optimal unit start-stop and line switching operation plan is given under the premise of ensuring economic operation.

Description

technical field [0001] The invention relates to the technical field of electrical information, in particular to a short-circuit current suppression method considering the start-up and stop of a unit and line switching. Background technique [0002] Due to the rapid growth of power load demand caused by rapid economic development and the rapid increase of power supply capacity, the short-circuit current level in the power system is getting higher and higher, and the problem of excessive short-circuit current is becoming more and more obvious. Therefore, how to limit the short-circuit current has become a problem that must be faced in the planning, dispatching and operation of the power grid. [0003] Limiting short-circuit current can start from many angles. Starting from the operation mode, it can be operated through the partition of the power grid. Although the short-circuit current can be reduced, it weakens the connection between the power grids and causes uneven power f...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the problems of inaccurate expression, non-optimal solution of obtained results, and failure to consider the influence of units on short-circuit current in existing studies on line switching and current limiting, combined with the mixed integer linear programming method, the research takes into account the start and stop of units and the display of line switching and switching. Optimal dispatching of power systems under the constraint of formula short-circuit current, that is, short-circuit current suppression method. The purpose of the present invention is to provide a short-circuit current suppression method considering unit start-stop and line switching

Images