Generally speaking, the cost of purchasing an air compressor for use includes two parts: purchase cost and maintenance cost, which account for 20% of the total cost; The other part is the energy consumption during the operation of the air compressor, which accounts for 80% of the operating cost of the air compressor, indicating that the energy consumption of the air compressor is very serious. But why does the air compressor consume so much energy? There are several main reasons for this.
1. When the air compressor is running, using the appropriate voltage for operation can result in a significant waste of energy due to asymmetric power supply voltage or excessively high or low voltage. Due to the imbalance of single-phase loads in the three-phase four wire low-voltage power supply system, the three-phase voltage of the motor is asymmetric, causing the motor to generate negative sequence torque, increasing the three-phase voltage asymmetry of the motor, causing the motor to generate negative sequence torque, and increasing the losses during motor operation. In addition, the long-term low voltage of the power grid causes the current of the motor to be higher during normal operation, resulting in increased losses. The greater the asymmetry of the three-phase voltage, the lower the voltage, and the greater the losses.
2. Poor maintenance and management of air compressors require regular maintenance after a certain period of operation. If there are deviations in the components, timely repair or replacement is necessary. If the motor and equipment are not repaired and maintained as required, and left to operate for a long time, not only will the efficiency be low, but also the losses will continue to increase.
3. The motor load rate of the air compressor is low, which may be due to improper selection of the motor, excessive surplus or changes in production process, resulting in the actual working load of the motor being much lower than the rated load. The motor, which accounts for about 30% to 40% of the installed capacity, operates at 30% to 50% of the rated load, resulting in low operating efficiency but no reduction in energy consumption, leading to a large amount of energy waste.
4. Outdated and old motors are still in use. The manufacturing process of these motors is relatively rough, but the technology is not as advanced as it is now. They use E-grade insulation, which results in large volume, poor starting performance, low efficiency, and energy consumption. The working efficiency is not proportional to the cost, which is also one of the reasons for the serious energy consumption of air compressors.
