An Emergency Control Method for Improving the Safety and Stability of Power System

Abstract

The invention discloses an emergency control method for improving the safe stability of a power system. An energy function method and a track predicting method are combined, real-time data of a PMU are adopted, the stabilizing measures, an implementation strategy and an implementation method of the system are determined quickly, and post supplement control in faults of a power grid is made to be possible. Power system dynamic characteristics based on the power grid energy function can be extracted by combining real-time data based on SCADA / EMS, wherein the extraction of the sensitivity of a generator tripping energy function and the sensitivity of generator tripping amount are included; fault instability possibly occurring is checked, a fault instability supplement strategy list is generated, the demands for the real-time performance of information on-line safety control over the power system are met, and the efficiency of the decision making of the safe stability control over the power system is improved. The control strategy of combining 'monitoring and analyzing of running modes of on-line circulation periods' and 'operation monitoring and post supplement control when large-disturbance motion faults occur to the system' is proposed, and the requirements of on-line control and time-domain simulation for the real time performance can be relieved.

Description

technical field [0001] The invention relates to the field of power systems, in particular to an emergency control method for improving the safety and stability of the power system. Background technique [0002] For machine cut stability control, in a specific large disturbance scenario, there are two main problems that need to be solved, one is the control location, that is, the sensitivity problem; the other is the control strength, which is actually the stability margin problem. These two problems present different complexities at different scales and different network structures [1] . In recent years, with the increasing development of global positioning system GPS technology and phasor measurement unit (PMU), new conditions have been provided for power system transient stability control [2] . The local transient energy function method proposed by Stanton et al. in the United States uses the PMU to measure the ratio of the maximum speed of the generator relative to the...

AI Technical Summary

Problems solved by technology

However, the actual system operation mode is often changed, and sometimes there will be mode mismatch and fault mismatch during the implementation process. The mode mismatch includes: (1) new and unconsidered ways of deteriorating system stability; (2) current In this mode, the number of units available for removal is less than the value in the strategy table; the fault mismatch includes: (1) The safety and stability control device refuses to operate, that is, some units that execute the removal order due to the safety control system during the safety control release process or the load refuses to move; (2) A fault beyond the expected fault set occurs, such as the extension of fault removal time, etc.

The method of "offline calculation and online matching" cannot effectively deal with the two situations of mode mismatch and fault mismatch, which will reduce the safety and stability of the power system under fault conditions

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