| Large cooling tower fans are used in the circulating water system of petrochemical industry widely, long time continous operation, and its energy consumption is very large. Variable frequency speed regulation is an effective method for energy-saving. In order to ensure the stable operation of the production, it must be safely operation. Therefore, it has a important practical significance to research the optimization energy-saving control system of group cooling tower fans.This subject developped the optimization energy-saving control system of6cooling tower fans in Tianjin sinopec branch chemical department. The main results are as follows:(1) Studied basic structure of the cooling tower fan and main performance parameters further, had a detailed to analysis and research on its aerodynamic characteristics. Through the study of industrial cooling tower fan energy saving method, concluded the best energy saving method——frequency control of motor speed and energy-saving.(2) Combined the optimal operation system and the security integration system, the optimization energy-saving control system was designed and developed. By discretized the variable frequency signal processing and terraced control of rotational speed, it avoid the problem of reduction of working life caused by fan frequency conversion speed shock effectively; And the organic combination of fan failure warning alarm system, realized the cooling tower fan safety control,reduced the fan maintenance times greatly, and solved the problem of false alarms and missed alarms in the monitoring process.(3) The design of frequency conversion control system should be on the premise of ensure safety in production operation. Designed the bypass system and hand automatic switching circuit to increases the reliability of production operation, which can satisfy the demands of system operating mode.(4) Combined PLC and frequency converter, realized the fan running frequency control of motor speed closed loop control; Through the configuration software, it realized the upper machine fan energy-saving control of the remote operation and real-time remote monitoring of running status.The optimization energy-saving control system of group cooling tower fans which was researched and manufactured in this paper was applied well in Tianjin sinopec branch chemical department. This system had significant energying-saving efficiency. And it was safe and reliable. And it had a high value promotion and broad market prospects. |
