Shenyang German Machine Hydralic Transmission Machinery Co., Ltd.
Address：No。 14 Shen Da Road, Shenyang flood diversion area
Comparison of hydraulic coupler accessories and frequency converters:
Without considering the obvious advantages of hydraulic coupling parts in easy maintenance and low price, we take a typical 1500kW induced draft fan as an example: hydraulic coupling = inverter + air conditioning system + filter + lubricating oil station and hydraulic oil station + gear box (driving the feed pump). The role of frequency converter is mainly reflected in speed regulation. Hydraulic coupling is reliable in all aspects such as soft start, speed regulation, improvement of torsional transmission of whole shaft system and routine maintenance. The details are as follows:
1, the price of the hydraulic coupler is generally more than 20% lower than the frequency converter (depending on the power and voltage), and the higher power is only 50-70% of the frequency of the frequency converter system.
2, the peak torque generated by all frequency converters may damage the flexible coupling and even the machine.
3. Because the inverter drives the machine directly by the motor, it is necessary to choose the motor which is more powerful than the actual motor in order to help to start the starting.
High order 4, inverter output will reduce the efficiency of the motor, increasing heating. In order to heat the heat, the motor needs to increase or install the cooling fan. (the heat dissipation of the motor is proportional to the speed of the motor, and the motor is designed to be a constant speed when the hydraulic coupling is used).
5, the frequency converter can not provide the hydraulic coupling without load starting, isolation shafting vibration and other characteristics.
6. The wave generated by the frequency converter may interfere with the main power supply. When starting, the pulse may affect the other electronic systems connected by the main power supply (PLC computer, etc.).
7, the filter can prevent the frequency converter from generating pulse when starting, but the filter is very expensive and will reduce the efficiency of the frequency converter.
8, the frequency and voltage stability of the power supply is very high. If the power supply is abnormal when the typhoon or thunderbolt leads to the power supply, it is very easy to fail.
9, the frequency converter has high requirements for temperature and humidity。 It needs to be placed in a clean room with air conditioning。 The expenditure is also considerable。 Even the standby air conditioning system may be needed, and the power consumption of the air conditioning system itself can not be ignored。
10。 The principle of the frequency converter determines its structure is far more complex than the hydraulic coupling, which leads to its reliability far below the hydraulic coupler。
11, when the frequency converter fails, most of the field personnel can't get rid of it. It must be contacted with the supplier's professionals, and its parts are expensive and no substitute. Hydraulic couplings are simple mechanical devices, easy maintenance and cheap parts.
12, the development of electronic parts is changing rapidly. After a few years, it is impossible to purchase spare parts of converters. It can be seen from the update of computer CPU. Spare parts of hydraulic couplings can be supplied for life.
13, the use of hydraulic coupling to save the installation space, the frequency converter to additional space to place transformers, air conditioners, wave filters and other auxiliary components。
14, hydraulic coupling is integrated into speed-up, lubricating oil system, speed regulation and other functions。 First, the inverter is unable to realize the drive machine (pump or fan) is higher than the motor speed operation, and additional purchase and installation of lubricating oil is needed。