| 摘要 |
PURPOSE:To reduce power consumption during operation of pumps by selecting a combination of a constant speed pump and a variable speed pump which can discharge a required flow and which requires the minimum power consumption among combinations of plural constant speed pumps and variable speed pumps, and operating the selected combination of the pumps. CONSTITUTION:Plural pumps 12 are operated in a combination of a constant speed pump and a variable speed pump. The terminal pressure is estimated from detection signals of a flow detector 18 and a discharge pressure detector 26, and a certain combination of the pumps among the plural pumps is selected in order to obtain designated terminal pressure. The selection is performed by a pump combination selector 22. Further, among the above combinations, a combination requiring the minimum power consumption is selected. Thus, the pumps combined according to the selection are operated. |
