电力抽水站受潮汐影响时的流量计算方法与精度控制

Discussion on the flow calculation method and precision control affected by tide in electric pumping station

受潮汐影响时,为了使机组在高效区运行或以最大流量抽水,泵站抽水流量不仅随着水位的涨落而变化,还可能同时受到叶片角度调整和机组变动等因素的影响.以江都水利枢纽大型泵站为例,分析了泵站在运行的不同时期,用不同方法计算流量的特点.结果表明:以下方法计算日平均流量,精度均达到规范要求,即净扬程日变幅在2m左右,用1d电功度数计算日平均流量;用水力因素法计算日平均流量时,以叶片角度为参数的净扬程与单机流量的关系曲线之间,应不大于0.25°;合并效率法以1d内24段制或12段制计算日平均流量,无需再考虑机组台数或叶片角度等大幅度调整.

Under the influence of tide,in order to satisfy the unit's operation in high efficiency area or pumping at maximum flow rate,the pumping flow not only varies with the fluctuation of water level,but also affected by the adjustment of blade angle and the change of unit. Taking the large - scale pumping station of Jiangdu Water Control Project as an example,the characteristics of calculating the flow rate by different methods in different operation periods of the pumping station were analyzed. The results showed that the accuracy of the following methods was up to the standard. The 1d electrical power was used to calculate the daily average flow when the daily variation of net head should be about 2m. When calculating the daily average flow rate with hydraulic factor method,the relationship between net head with blade angle and single unit flow should be less than 0. 25°. Using the combined efficiency method to calculate the daily average flow in the 24 - segment system or 12 - segment system within 1d was no need to consider the number of units or blade angle and other large - scale adjustments.