Abstract
In the thesis, the disadvantages and problems need to be resolved of current supporting water system are briefly analyzed, and a new system, which has great advance in automation, reliability and saving energy, is studied and described.
This thesis consists of five chapters．Chapter one clarifies the application background and significance of the supporting water system and main contents of research. Chapter two introduces the overall project of the new auto－control system, including craft demand, constitution, work principle and the selection of the main electrical devices．Chapter three emphasizes the principle of the software and hardware part in control system. Chapter four, we analyze the exploitation of control system, specifying on PLC programmer and introduces the principle, parameter installation of PID control. The last chapter is the conclusion of the whole research and presents some debug result.
This article uses the programmable controller (PLC), the use frequency conversion velocity modulation control technology, with the aid of the sensor and the execution and so on the modern industry control commonly used control portion and its the correlation control algorithm, designed and has realized the frequency conversion velocity modulation constant pressure water supply system. This system has the structure simply, the operation simple, the movement is reliable and so on the characteristic. May greatly enhance the reliability which two time supplies water, compares with the barometric pressure water supply equipment may conserve energy above 20%.
[KEY WORDS]： PLC Frequency conversion PID Water supply system
