Electric Motor Energy Saving Solutions
While the motor brings more convenience to production and life, its energy consumption cannot be ignored. In the face of the rising cost of purchasing mechanical products and the gradual increase in energy consumption, high-voltage motor maintenance manufacturers will recommend choosing energy-saving motors, or transforming the original motor, these are good choices for enterprises to save costs.
Select Energy-saving Motor
Compared with ordinary motors, the high-efficiency motor optimizes the overall design, selects high-quality copper windings and silicon steel sheets, reduces various losses, reduces losses by 20%~30%, and improves efficiency by 2%~7%.
Select Appropriate Motor Capacity
The state has made the following regulations for the three operating areas of three-phase asynchronous motors: the economic operation area is between 70% and 100% of the load rate; the general operation area is between 40% and 70% of the load rate; the load rate is 40% The following are non-economic operating areas. Improper selection of motor capacity will undoubtedly result in waste of electric energy. Therefore, using a suitable motor to improve the power factor and load rate can reduce power loss and save energy.
Use Magnetic Slot Wedge
The magnetic slot wedge mainly reduces the no-load iron loss in the asynchronous motor. The no-load additional iron loss is generated in the stator and rotor iron core by the harmonic magnetic flux caused by the cogging effect in the motor. The high-frequency additional iron loss induced by the stator and rotor in the iron core is called pulse vibration loss. In addition, the teeth of the stator and rotor are sometimes aligned and sometimes misaligned, and the magnetic flux of the tooth cluster on the tooth surface fluctuates, which can induce eddy currents in the tooth surface line layer, resulting in surface loss. Pulse vibration loss and surface loss are collectively called high-frequency additional losses, which account for 70% to 90% of motor stray losses, and the other 10% to 30% are called load additional losses, which are generated by leakage magnetic flux. Although the use of magnetic slot wedges will reduce the starting torque by 10% to 20%, the iron loss of the motor using magnetic slot wedges can be reduced by 60k compared to the motor using ordinary slot wedges, and it is very suitable for no-load or light-load starting motor transformation .
Adopt Y/△ Automatic Conversion Device
In order to solve the waste of electric energy when the equipment is lightly loaded, on the premise of not replacing the motor, a Y/△ automatic conversion device can be used to achieve the purpose of saving electricity. Because in the three-phase AC power grid, the voltage obtained by the different connection of the load is different, so the energy absorbed from the power grid is also different.
Motor Power Factor Reactive Compensation
Improving power factor and reducing power loss are the main purposes of reactive compensation. The power factor is equal to the ratio of active power to apparent power. Usually, a low power factor will cause excessive current. For a given load, when the supply voltage is constant, the lower the power factor, the greater the current. Therefore, the power factor is as high as possible to save electric energy.
Frequency Conversion Speed Regulation
Most of the loads of fans and pumps are selected according to the demand for full-load work. In practical applications, most of the time they are not in full-load work. Because it is difficult to adjust the speed of AC motors, windshields, return valves, or start and stop times are often used to adjust the air volume or flow. At the same time, it is difficult for large motors to frequently start and stop under the power frequency state, and the power shock is large, which will inevitably cause power loss and Current impact when switching on and off. It is the most scientific control method to directly control the load of fans and pumps with the frequency converter. When the motor runs at 80% of the rated speed, the energy saving efficiency is close to 40%. At the same time, closed-loop constant pressure control can also be realized, and the energy saving efficiency will be further improved. . Because the frequency converter can realize the soft stop and soft start of large motors, it avoids the voltage shock when starting, reduces the failure rate of the motor, prolongs the service life, and also reduces the capacity requirements and reactive power loss of the power grid.
Liquid Speed Regulation of Winding Motor
The liquid resistance speed control technology is developed on the basis of the traditional product liquid resistance starter. The resistance is adjusted by changing the distance between the plates to achieve stepless speed regulation. This makes it have good starting performance at the same time. It is powered on for a long time, which brings about the problem of heat generation. Due to the unique structure and reasonable heat exchange system, its working temperature is limited to a reasonable temperature. The liquid resistance speed regulation technology for winding motors has been rapidly popularized due to its advantages of reliable operation, convenient installation, large energy saving, easy maintenance and low investment. For some wound motors that do not require high speed regulation accuracy, wide speed regulation range, and infrequent speed regulation, such as large and medium-sized wound asynchronous motors of fans, pumps and other equipment, liquid speed regulation has a significant effect.