Introduce
YFB3 series dust explosion-proof low voltage three-phase asynchronous motor
Frame number: H80-355
Capacity: 0.55~315kW
Number of poles: 2~10P
Voltage: 720v and below
Pump motor loss is too high how to do?
- Variable loss varies with load, including stator resistance loss (copper loss), rotor resistance loss and brush resistance loss.
- Fixed loss is independent of load, including core loss and mechanical loss. The iron loss is also composed of hysteresis loss and eddy current loss, which is proportional to the square of the voltage, and the hysteresis loss is inversely proportional to the frequency.
- Other stray losses are mechanical losses and other losses, including the friction loss of bearings and the wind resistance loss caused by rotation of fans, rotors, etc.
Five measures to reduce motor losses:
First, stator loss: The main methods to reduce the motor stator I^2R loss are:
- Increase the cross-sectional area of the stator slot. In the case of the same stator outer diameter, increasing the cross-sectional area of the stator slot will reduce the magnetic circuit area and increase the magnetic density of the teeth.
- increase the stator slot full slot rate, this low voltage small motor effect is better, the application of the best winding and insulation size, large wire cross-sectional area can increase the stator slot rate.
- shorten the stator winding end length as much as possible, the stator winding end loss accounts for 1/4 ~ 1/2 of the total winding loss, reduce the winding end length, can improve the motor efficiency. Experiments show that the end length is reduced by 20% and the loss by 10%.
shorten the stator winding end length as much as possible, the stator winding end loss accounts for 1/4 ~ 1/2 of the total winding loss, reduce the winding end length, can improve the motor efficiency. Experiments show that the end length is reduced by 20% and the loss by 10%.
1, the use of heat treatment and finishing to reduce the rotor surface short circuit.
2, rotor groove inner surface insulation treatment.
3,Reduce harmonics by improving stator winding design.
4, improve the rotor groove design and coordination to reduce harmonics, increase the fixed and rotor tooth slots, the rotor groove shape design into a inclined slot, the use of series sinusoidal winding, spread winding and short distance winding can greatly reduce high harmonics; It is an effective method to reduce additional stray loss by using magnetic groove mud or magnetic groove wedge instead of traditional insulated groove wedge and filling the groove of motor stator core with magnetic groove mud.
Third, wind friction loss: wind friction loss accounts for about 25% of the total motor loss, should be paid due attention to. Friction loss is mainly caused by bearings and seals, which can be reduced by the following measures:
1, minimize the size of the shaft, but to meet the requirements of output torque and rotor dynamics.
2, the use of high-efficiency bearings.
3,Use efficient lubrication system and lubricant.
4,Adopt advanced sealing technology.
Four, rotor loss: motor rotor I^2R loss is mainly related to rotor current and rotor resistance, the corresponding energy-saving methods are mainly:
1, reduce the rotor current, which can be considered from the two aspects of improving the voltage and motor power factors.
2,Increase the cross-sectional area of the rotor slot.
3, reduce the resistance of the rotor winding, such as the use of thick wire and low resistance materials, this is more meaningful for small motors, because small motors are generally cast aluminum rotor, if the use of cast copper rotor, the total loss of the motor can be reduced by 10% to 15%, but today’s cast copper rotor required high manufacturing temperature and technology has not been popularized, its cost is higher than the cast aluminum rotor 15% to 20%.
Five,Iron core loss: Motor iron loss can be reduced by the following measures:
1, reduce the magnetic density, increase the length of the core to reduce the magnetic flux density, but the amount of iron used by the motor increases.
2, reduce the thickness of the iron chip to reduce the loss of induced current, such as using cold-rolled silicon steel instead of hot-rolled silicon steel sheet can reduce the thickness of the silicon steel sheet, but the thin iron core sheet will increase the number of iron chips and motor manufacturing costs.
3, the use of good magnetic permeability cold rolled silicon steel sheet to reduce hysteresis loss.
4, the use of high-performance iron chip insulation coating.
5, heat treatment and manufacturing technology, the residual stress after iron chip processing will seriously affect the loss of the motor, silicon steel sheet processing, cutting direction, impact shear stress on the loss of the core is greater. Cutting along the rolling direction of the silicon steel sheet and heat treatment of the silicon steel punching sheet can reduce the loss of 10% to 20%.
Maintenance methods
Professional Motor Maintenance and Repair Center Motor Maintenance Process: Cleaning the stator and rotor – Replacing carbon brushes or other components – Vacuum F-level pressure immersion paint – Drying – Calibrating dynamic balance.1. The usage environment should be kept dry regularly, the surface of the motor should be kept clean, and the air inlet should not be obstructed by dust, fibers, etc.2. When the thermal protection of the motor continuously operates, it should be determined whether the fault is caused by the motor being overloaded or the setting value of the protection device being too low. Only after eliminating the fault can it be put into operation.3. Ensure good lubrication of the motor during operation. A typical electric motor should be lubricated or replaced after running for about 5000 hours. If the bearings are found to be overheated or the lubrication deteriorates during operation, the hydraulic system should replace the lubricating grease in a timely manner. When replacing the lubricating grease, the old lubricating oil should be removed, and the oil grooves of the bearings and bearing covers should be cleaned with gasoline. Then, fill 1/2 (for 2 poles) and 2/3 (for 4, 6, and 8 poles) of the cavity between the inner and outer rings of the bearing with ZL-3 lithium grease.4. When the service life of the bearings ends, the vibration and noise of the motor operation will significantly increase. When the radial clearance of the bearings reaches the following values, the bearings should be replaced.5. When disassembling the motor, the rotor can be removed from either the shaft extension end or the non extension end. If it is not necessary to remove the fan, it is more convenient to remove the rotor from the non shaft extension end. When removing the rotor from the stator, it should be prevented from damaging the stator winding or insulation.6. When replacing the winding, it is necessary to record the form, size, number of turns, wire gauge, etc. of the original winding. When these data are lost, they should be obtained from the manufacturer. Changing the original design winding arbitrarily often deteriorates the performance of one or several aspects of the motor, and even makes it unusable.