一种计及微地形修正的输电线台风风险预警方法

台风过境时,较大的风力往往会引发风偏放电、断线、倒塔等事故,是对沿海地区电网安全可靠运行威胁最大的自然灾害之一。由于台风灾害的高风险性,建立台风预警体系能更经济有效的提升电网抵御台风灾害的能力。现有的电网台风风险预警方法直接使用气象局提供的区域性预测风速,并未考虑具体线路所处的微地形环境对风速的影响,易出现漏警以及虚警。因此,提出一种计及微地形影响的输电线台风风险预警方法。该方法把预警区域按经纬度划分为0.01°×0.01°的网格,将网格内的输电设备与网格微气象、微地形信息关联,建立了输电线微地形条件下的风速修正系数计算方法,可更准确地辨识遭受台风灾害影响的线路集并按风险等级进行预警。实例验证了方法的可行性和有效性。

A typhoon risk early warning method for power transmission line considering micro-terrain correction

When a typhoon transits a region, the accidents of line breakage and tower collapse often occur due to the large wind force, so it is one of the natural disasters which are the most threat to operational reliability of transmission lines in coastal areas. Because of the high risk of typhoon disaster, establishing a typhoon early warning system is more economical and efficient to enhance the ability of power grid to withstand typhoon disasters. The existing typhoon risk early warning method for power grid uses the regional forecasting wind speed provided by the meteorological agency directly, which does not take the influence of micro-terrain around specific line on the wind speed into account, thus the missed alarm and false alarm are easy to appear. Therefore, a typhoon risk early warning method for power transmission line considering micro-terrain correction is proposed in this paper. The warning area is divided into 0.01°×0.01° grids by longitude and latitude in this method, and transmission equipment in each grid is associated with the microclimate information and micro-terrain information of the grid. The calculation method of correction factor of wind speed for transmission line under micro-terrain conditions is set up, in order to identify the set of lines that may suffer from typhoon disaster more accurately, and early warning is conducted according to risk level. The feasibility of this method is proved by an instance.