并联泵站群日优化运行方案算法

Algorithm of daily operation scheme for parallel pumping stations

提出了并联泵站群日优化运行数学模型,该模型以并联泵站群日提水费用最少为目标函数,以各时段机组叶片角或转速为决策变量.考虑站间不同工况调节方式,采用大系统二级分解-动态规划聚合法进行求解.首先以泵站日提水耗电费用最少为目标,泵站提水量的分配为协调变量,将该模型分解成若干个泵站多机组日优化运行一级子模型;再以单机组日提水耗电费用最少为目标,机组提水量的分配为协调变量,将一级子模型分解为若干个单机组日优化运行二级子模型.该二级子模型以机组叶片安放角或机组转速为决策变量,机组提水量的离散值为状态变量,采用动态规划方法求解.构造的聚合模型以各机组提水量为决策变量,并联泵站群提水量的离散值为状态变量,同样采用动态规划方法求解.该方法可以解决不同工况调节方式、不同时段划分及不同日均扬程下并联泵站群的日优化运行问题.以淮阴一、三站并联运行为例,作了日优化运行计算,结果表明:各日均扬程下满负荷、80%负荷、60%负荷优化运行单位费用,较定角恒速运行分别平均节约10.53%,26.54%,34.40%.

Considering different condition adjustment,two stages decomposition-dynamic programming aggregation method was introduced to solve the mathematical model of daily optimal operation for parallel pumping stations which took the minimal daily electric cost of parallel pumping stations as objective function,the flow or speed of each unit as decision variable.Taking minimal daily electric cost of single pump station as objective function,allocation of water quantity pumped by each station as coordinated variable,this model was decomposed into several first stage sub-model of daily optimal operation for single pump station.Then taking minimal daily electric cost of single pump unit as objective function,allocation of water quantity pumped by each unit as coordinated variable,the first stage sub-model was decomposed into several second stage sub-model of daily optimal operation for single pump unit which takes the blade angle or unit speed as decision variable,the discrete value of water quantity pumped by each unit as state variable,and was solved by means of dynamic programming method.The constructed aggregation model took daily water quantity pumped by each pump unit as decision variable,the discrete value of water quantity pumped by parallel station group as state variable,and was also solved by dynamic programming method.This method could solve the optimal operation issues for parallel pumping stations with various operation modes,time period divisions and daily average heads of each station,and also provide theoretical support for the study on optimal operation of multi-stage pumping stations.Taking No.1,3 Huaiyin pumping station as a study case,a series of optimization calculations were carried out.The results showed that the unit cost of optimal operation under 100%,80%,and 60% loads within all average daily heads had an average energy consumption saving of 10.53%,26.54% and 34.40%,respectively,compared with the operation with fixed blade angle and constant speed.