On-line evaluation method of backup safety margin in power system operation

Abstract

Disclosed is an online evaluation method of a safety margin of an operating reserve in a power system, which belongs to the technical field of power system operation and control. A post-fault steady operation state of the system is obtained by considering protection and through time-domain simulation of action of an automatic safety device, and active power sensitivity of the operating reserve for power transmission equipment and a power transmission corridor is calculated based on a direct-current (DC) power flow equation of the state. A maximum capacity of the operating reserve that is useful for actual control of a steady state frequency is obtained by solving an optimization function considering a controllable interval of the operating reserve, an overload limit of the power transmission equipment and a safety and stability limit of the power transmission corridor, and aiming at maximizing the operating reserve. A maximum controllable quantity of the steady state frequency is calculated in combination with power and frequency static characteristic coefficients, achieving online evaluation of a safety margin of the operating reserve taking faults into consideration.

Description

technical field [0001] The invention belongs to the technical field of power system operation and control. Specifically, the invention relates to an online quantitative evaluation method for the frequency control capability of power system operation backup after an expected failure, taking into account safety and stability constraints. Background technique [0002] The power system operation backup is mainly set up to ensure the system frequency quality requirements after the occurrence of expected failures (including generator output fluctuations, load fluctuations, short circuits, tripping and DC blocking, etc.). The standby is monitored and assessed for its actual ability to safeguard the system's frequency quality. [0003] The existing on-line monitoring and evaluation methods for operating reserve use the difference between the total maximum power generation output, the total minimum power generation output, and the total load in the current operating state to represen...

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Problems solved by technology

[0005] The purpose of the present invention is: for the existing on-line monitoring and evaluation method for running standby, the predictive faults are considered in a unified manner based on their impact on the power balance of the power system, and no distinction is made between different predictive faults with the same power variation and different impacts on the power system , and not considering the constraints of transmission equipment overload limit and transmission channel safety and stability limit, considering the dynamic behavior of the primary and secondary equipment of the power system after the expected failure, and taking into account the overload of the transmission equipment in the standby adjustment of the standby adjustment after the expected failure Based on the constraints of quota and transmission channel security and stability quota, an online evaluation method of power system operation backup safety margin considering expected faults is proposed to meet the actual needs of dispatching operation control

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