Prevention and control method of online risk assessment based on wind power fluctuation

Abstract

The invention discloses a prevention and control method of online risk assessment based on wind power fluctuation. The prevention and control method comprises the steps of: predicting wind power output ranges at a future moment t<h+1> and corresponding probabilities by using a Markov chain model based on wind power fluctuation; for each predictive wind power output range, estimating a power grid operating state by using a local linear processing method; acquiring the severity of the corresponding wind power output range by using an obtained result and a severity function capable of reflecting the stability margin of a static voltage; acquiring an operating risk indicator in a computation period by using an acquired result; judging whether the risk indicator exceeds a set threshold value; if so, entering into a prevention and control model; on the premise of not discarding wind, adopting prevention and control to guarantee the power grid operating state change caused by random wind power fluctuation in a stability domain and to reduce an operating risk caused by short-term wind power fluctuation, controlling the risk indicator within the set threshold value; if not, carrying out risk assessment at a next moment.

Description

technical field [0001] The invention relates to the technical field of grid safety assessment, in particular to a prevention and control method based on online wind power fluctuation risk assessment. Background technique [0002] As a new type of clean energy, wind energy has become the development focus of many countries' energy strategies in the world. China's wind power installed capacity reached 114GW in 2014, ranking first in the world, and the government plans to increase the annual installed capacity of wind power by at least 20GW until 2020. The vigorous development of wind power can reduce greenhouse gas emissions and save fossil energy consumption, but due to the uncertainty and intermittency of wind power output, its large-scale grid connection has brought huge challenges to the safe operation of the grid. [0003] With the continuous increase of wind power grid-connected capacity, the impact of wind power randomness and uncontrollable multi-output scenarios unde...

AI Technical Summary

Problems solved by technology

In 2012, when there was no system failure in the Zhangbei wind power base, the voltage fluctuated greatly, causing a large area of ​​wind turbines to be disconnected from the grid, causing serious economic losses

The preventive control in the above literature is aimed at the fault set caused by line interruption, and does not involve the uncertainty of power fluctuations. With the increase of wind power penetration rate, the safety problems caused by random fluctuations of wind power output will become more and more significant, but for wind power On-line preventive control of output random fluctuations is still lack of discussion

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