Water Supply System of Constant Pressure Based on PLC Control

Abstract

An automatic regulation water supply system based on PLC and VVVF is proposed. The control system regulates the output of VVVF by PLC, and with controlling the number of the working water pump and the speed of motor rotate automatically, achieves automatically regulating water supply of constant pressure by closed loop and transferring the data, then the PID adjustment method is taken to adjust variable frequency pump continuously and regulate the pump frequency combined with constant pressure water supply in the whole flow range. This thesis explains water supply system’s energy conservation principle of pump of speed control according to characteristic curve of running pipelines and water pump. The system can supply the water with the constant pressure and save the energy efficiency.