The main idea of water plant control system is to adjust water supply according to water consumption. According to the principle of water pump pipeline, there are two ways to regulate the water supply flow: (1) throttle valve regulation, increase valve opening, increase flow, reduce valve opening, reduce flow. Speed regulation, increase the speed of the pump, increase the flow, reduce the speed of the pump, reduce the flow. For the application of water plant, the speed regulation method has good energy saving effect and is a common way for water pump speed regulation