The circulating water cooling tower fan is composed of three groups of 37KW asynchronous motors. The annual operating time is about 7000 hours/unit, and the annual power consumption is about 777,000 KWh. Before equipment transformation, the operation of the cooling tower fan was manually controlled, and the three sets of motors were started at power frequency. Turn on one to three sets of fans to run according to the weather and operating experience.

  In 2003, the frequency conversion energy-saving transformation was carried out. The entire frequency conversion system selected 2 LG/SV037IH-4 dual-power inverters to form a redundant operation structure, and LG/MASTER-K120 series K7M-DR40U PLC and LG man-machine interface formed the control operating system. After the transformation, The system adopts fully automatic closed-loop control technology. According to seasonal changes and actual production processes, it collects on-site real-time temperature data and compares preset values, and automatically adjusts the number and operating frequency of the motor through the inverter, and runs fully automatically. The human factor is discarded, the loss of energy is avoided, and the energy saving effect is very good.