Research on Optimal Operation by Adjusting Blade Angle in Jiangdu No. 4 Pumping Station of China

摘要

A Nonlinear Programming Model for the optimal day-operation of multi-units pump in one pumping station by adjusting blade angle has been put out, where the peak-valley electricity prices is considered in this paper. The model takes the minimal operation cost of pump assembly as objective function. In the meantime, the periods are defined as stage variables. The blade angle and the number of the working-pumps are expressed as decision variables and the water volume pumped in one day as constraint condition, The problem is very difficult to be settled by regular methods. This paper presents a new method which adopts experimental optimization method of adjusting blade angle in different periods and linear integral programming method to select the number of pumps. After applying the method to the optimal operation of Jiangdu No.4 pumping station, which is the source pump station of Eastern Rome Project of South-to-North Water Divetsion (Where there are seven pumps and the design flow rate of single-unit is 30.0m~3/sec), we get the results which are as follows(1) With the constraint conditions of typical tidal process which are average tidal levels from December to February of next year, designed average pumping head of 7.8m, and the operation load at I 00%,80%,60% of full-load(the water volume when the pumps working with the blade angle of 0 degree and the speed of 150r/min in full day), the relative energy-saving reaches 5.18%33.02% comparing with the -state of keeping the pump operating at its designed blade angle which is 0 degree when considering peak-valley electricity prices. While not considering the peak-. valley electricity prices, the number is 1.96%～ 9.71%, and less load corresponds to more cost-saving. (2) The key factory an deciding the operation state of pumps is electricity price when we consider the peak-valley electricity prices. All the pumps should be working and the blade angle should be in the largest state when at the valley price, while the number of the working pumps should be reduced, then the angle should be varied afterwards when at the peak price in order to reduce the cost. The key factor on deciding the operation state of pumps is tidal process when the electricity price isunchanged in one day. More-pumps should be working and the angle should be in the largest state as possible when at high tidal level while the number of the working pumps should be reduced, then the angle should be varied afterwards when at low tidal level.