Motor small encyclopedia: motor six kinds of energy saving schemes.
The motor energy consumption performance is mainly in the following aspects:
1. Low motor load rate. Due to improper motor selection, large amount of rich or production process change, will make the actual work load is far less than the rated load of the motor, about 30% ~ 40% of the installed capacity of motor running in 30% ~ 30% of the rated load, low operating efficiency.
2. The power supply voltage is not symmetrical or the voltage is too low. Due to the three phase four wire system of low voltage power supply system of single-phase load imbalance, makes the asymmetry of three-phase voltage of the motor, negative sequence torque motor, increasing the asymmetry of three-phase voltage of the motor, the motor produces negative sequence torque, increase the loss of the motor running. In addition, the long-term low voltage of the power grid makes the motor current of the normal operation be larger, thus the loss is increased. The greater the asymmetry of the three-phase voltage, the lower the voltage, the greater the loss.
3. The old and old motor is still in use. These motors adopt E - grade insulation, large volume, poor start-up performance and low efficiency. Despite years of transformation, there are still many places to use.
4. Poor maintenance management. Some units do not maintain the motor and equipment according to the requirements, running the motor for a long time, which makes the loss increase continuously.
Therefore, it is worthwhile to study the energy conservation plan for these energy consumption.
There are six types of motor energy saving schemes:
1. Select energy-saving electric motors. Efficient motor compared with the ordinary motor, optimize the overall design, selects the high quality of copper winding and silicon steel sheet, reduces the various losses, loss decreased by 20% ~ 20%, the efficiency is increased by 2% ~ 7% investment capital is recovered in general is 1 ~ 2 years, some for a few months. Compared with the J02 series, the efficiency of the motor is 0.413% higher than that of the J02 series. Therefore, it is imperative to replace the old motor with efficient electric motors.
Second, the appropriate choice of motor capacity to achieve energy saving. Countries for three phase asynchronous motor operating area are the following three rules: the load rate is between 70% ~ 100% area of economic operation load rate is between 40% ~ 70% for general operation load rate below 40% for the non-economic operation areas. Improper motor capacity selection will undoubtedly result in waste of electricity. Therefore, suitable electric motors are adopted to improve the power factor and load rate, which can reduce power loss and save energy.
3. Use magnetic groove wedge instead of the original slot wedge. The magnetic slot wedge mainly reduces the load loss in the asynchronous motor, and the no-load additional iron loss is generated in the stator and rotor iron core by the harmonic flux caused by the slot effect in the motor. The high frequency additional iron loss induced by stator and rotor in iron core is called pulse vibration loss. In addition, the stator and rotor teeth are sometimes staggered and staggered. The magnetic flux of the tooth surface is changed, and the surface loss can be generated by the induced eddy current at the surface of the tooth surface. Pulse vibration loss and surface loss are combined with high frequency additional loss. They account for 70%~90% of the stray loss of the motor, and the other 10%~30% is called load additional loss, which is generated by leakage flux. Although the use of magnetic slot wedge can make the start torque by 10% ~ 20%, but USES the magnetic slot wedge motor than using common slot wedge motor iron loss can be reduced 60 k, and fit in with the no load or light load to start the motor.
4. Use the Y/ delta automatic switching device. In order to solve the waste phenomenon of electric energy when the equipment is light load, it is possible to use the automatic switching device of Y/ delta to achieve the purpose of saving electricity without changing the motor. Because the voltage is different in the three-phase ac power grid, the energy absorbed from the grid is different.
The power factor of the motor is reactive. To improve the power factor, reducing power loss is the main purpose of reactive power compensation. Power factor is equal to the ratio of the active power and apparent power, usually, the power factor is low, will cause too much electricity, for a given load, when the power supply voltage must be, the power factor is lower, the greater the current. So the power factor is as high as possible to save energy.
Vi. Winding motor liquid speed adjustment. Liquid resistance speed regulation technology is developed on the basis of traditional liquid resistance starter. It is still used to adjust the resistance of plate spacing to achieve stepless speed regulation. Which makes it has a good starting performance at the same time, the electricity for a long time, it brought a fever warming, with unique structure and reasonable heat exchange system, its working temperature is limited under the reasonable temperature. Coiling machine with liquid resistance speed control technology, with its reliable operation, easy installation, energy saving, easy maintenance and low investment, greater got rapid promotion, for some of the speed control accuracy is not high, asked not to wide range of speed regulation, and do not frequent wound rotor motor speed control, such as fan, water pump equipment of large and medium-sized wound rotor asynchronous motor use liquid control effect is remarkable.