Efficient and energy-saving motor technology and industry development significance

From the perspective of energy conservation and environmental protection, high-efficiency motors are the current international development trend, and the United States, Canada, and Europe have successively issued relevant regulations. According to the operating time of electric motors in Europe, the CEMEP standard divides efficiency into three levels: eff1 (highest), eff2, and eff3 (lowest), which were implemented step by step from 2003 to 2006. The latest IEC60034-30 standard divides motor efficiency into four levels: IE1 (corresponding to eff2), IE2 (corresponding to eff1), IE3, and IE4 (highest). China promises to implement IE2 and above standards from July 1, 2011.
At present, industrial energy consumption in China accounts for about 70% of the total energy consumption, with motor energy consumption accounting for about 60% to 70% of industrial energy consumption. Coupled with non industrial motor energy consumption, the actual energy consumption of motors accounts for over 50% of the total energy consumption. However, the proportion of efficient and energy-saving motor applications is low nowadays. According to a sampling survey of 198 motors from key domestic enterprises conducted by the National Center for Quality Supervision and Inspection of Small and Medium Sized Motors, only 8% of the high-efficiency and energy-saving motors that reach level 2 or above are considered to be of great waste to the entire society's resources.
Energy saving measures for high-efficiency motors
Energy conservation of electric motors is a systematic engineering project that involves the entire life cycle of electric motors. From the design and manufacturing of electric motors to the selection, operation, adjustment, maintenance, and scrapping of electric motors, the effectiveness of energy-saving measures should be considered from the entire life cycle of electric motors. In this regard, both domestic and foreign efforts should be made to improve efficiency from the following aspects.
The design of energy-saving motors refers to the use of modern design methods such as optimization design technology, new material technology, control technology, integration technology, and experimental detection technology to reduce power loss of the motor, improve the efficiency of the motor, and design an efficient motor.
Electric motors, while converting electrical energy into mechanical energy, also lose some of their own energy. Typical AC motor losses can generally be divided into three parts: fixed loss, variable loss, and stray loss. Variable losses vary with load, including stator resistance losses (copper losses), rotor resistance losses, and brush resistance losses; Fixed losses are independent of load, including core losses and mechanical losses. Iron loss is composed of hysteresis loss and eddy current loss, which are proportional to the square of voltage, and hysteresis loss is also inversely proportional to frequency; Other stray losses include mechanical losses and other losses, including friction losses of bearings and wind resistance losses caused by rotation of fans, rotors, etc.
Characteristics of high-efficiency motors
1. Saving energy and reducing long-term operating costs, it is very suitable for use in textiles, fans, water pumps, and compressors. By saving electricity for one year, the cost of motor purchase can be recovered;
2. Directly starting or using a frequency converter for speed regulation can fully replace the asynchronous motor;
3. The rare earth permanent magnet high-efficiency energy-saving motor itself can save more than 15% of electrical energy compared to ordinary motors;
4. The power factor of the motor is close to 1, improving the quality factor of the power grid, without adding a power factor compensator;
5. Low motor current, saving transmission and distribution capacitance, and extending the overall operating life of the system;
6. Energy saving budget: Taking a 55 kW motor as an example, efficient motors save electricity compared to regular motors