Optimization of stepless speed regulation drive
in the new solution of direct drive of cooling tower ventilation system, the traditional reducer is not used for speed change, but the stepless speed regulation control system is used instead. Because this scheme uses fewer moving parts, its reliability is significantly improved; It can also save energy and reduce the noise when working
air cooling tower is a common component in office buildings and industrial heating, ventilation and air conditioning systems. In this part, the large fan cools the water containing cooling medium. Baldor company developed and designed a new direct drive solution for this cooling system without using traditional reducer; Thus, the reliability and economy of this cooling ventilation device are significantly improved
according to Baldor company, the fan with standard configuration uses AC induction motor, and the power output shaft of the reducer is directly connected with the fan through the disc clutch of the transmission. The function of the reduction mechanism is to reduce the speed of the AC induction motor to the required speed range when the cooling fan works. This system has many defects and deficiencies, such as: due to the high speed of the transmission, regular maintenance is required; Strong vibration, wear and noise caused by imbalance when transmitting power; In addition, the complex power transmission system also brings a lot of energy loss
the cooling tower fan drive technical scheme is based on the permanent magnet and the control system which will make the oil pump and pipeline produce noise and vibration step motor and adjust the speed, so the use of reducer can be omitted.
based on the permanent magnet excitation system of synchronous motor, the VS1 cooling tower direct drive system of Baldor company can improve the low speed direct drive of the cooling fan with stepless speed regulation control. The RPM series synchronous motor used has a constant output torque in the whole speed range from zero to the highest speed. In addition, this kind of motor does not need the common cast iron shell of AC motor, and the metal material required to generate torque magnetic field is omitted. In this way, there will be no mechanical loss of the drive shaft and transmission to new situations and problems in the implementation of the plan, and the efficiency of the whole system will be improved. Under the control of VS1 drive system with built-in speed control algorithm language, the speed regulation of synchronous motor can be effectively realized. 2. The protector's products have also achieved a qualitative Pentium method in terms of structural integrity. According to the manufacturer, after using this system, the rotating speed can be reduced in the working time outside the peak load to achieve the goal of energy saving
due to the omitted drive shaft and reducer, the number of moving parts in this solution is also greatly reduced; Thus, the working reliability and economy of the whole cooling fan system have been improved
in order to give the best protection to the synchronous motor working in the humid environment, the surface of the stator winding of the synchronous motor is coated with an insulating layer of epoxy resin material. At the power output shaft of the motor, the wear-resistant INPRO labyrinth shaft end connection mode is adopted; According to the manufacturer, it can well prevent the invasion of moisture
before leaving the factory, the performance of this stepless speed regulation cooling method was tested in two cooling towers, and the diameter of the cooling fan used in the test was 5.5m. The results of energy detection of the drive system show that compared with the traditional drive system, this stepless speed regulating cooling fan can save 13% energy. Since the space required for installing this system is less, the cooling fan system that now uses the reducer can be transformed and supplemented with this stepless speed regulation cooling fan system. The rated driving power of this system is 7~145kw, the fan speed is 150~500r/min, and the fan diameter is 2.1~5.5m
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