Commen motor: The motor is a device that converts electrical energy into mechanical energy. 70% -95% of the electrical energy absorbed by the motor is converted into mechanical energy. This is often called the efficiency value of the motor. It is an important technical indicator of the motor, and the remaining 30% 5% is consumed by the motor itself due to heat and mechanical loss, so this part of the power is wasted.
High-efficiency motor: A motor with a higher power utilization rate is called a high-efficiency motor, referred to as "high-efficiency motor".
For ordinary motors, it is not easy to increase efficiency by 1 percentage point. The material will increase a lot, and when the motor efficiency reaches a certain value, no matter how much material is added, it will not be improved. Most of the high-efficiency motors on the market today are replacement products of three-phase asynchronous motors, which means that the basic working principle has not changed.
High-efficiency motors improve motor efficiency mainly through:
1. Increase material: increase the outer diameter of the core, increase the length of the core, increase the size of the stator slot, and increase the weight of the copper wire to increase the efficiency. For example: Y2-8024 motor increases the outer diameter from the current Φ120 to Φ130 Some foreign countries have increased Φ145 while increasing the length from 70 to 90. The amount of iron per motor is increased by 3Kg. The copper wire is increased by 0.9Kg.
2. Use silicon steel sheet with good magnetic permeability. In the past, hot-rolled sheet with large iron loss was used, and now high-quality cold-rolled sheet with low loss, such as DW470. Even lower DW270.
3. Improve processing accuracy, reduce mechanical loss, replace small fans, reduce fan losses, and use high-efficiency bearings.
4. Optimize the electrical performance parameters of the motor, and optimize the parameters by changing the groove shape.
5. Use cast copper rotor (complex process and high cost).
Therefore, to make a truly efficient motor, the cost of design, raw materials, and processing is much higher, so that electricity can be converted into mechanical energy to the greatest extent.
Energy-saving measures for high-efficiency motors:
Motor energy saving is a systematic project that involves the entire life cycle of the motor. From the design and manufacture of the motor to the selection, operation, adjustment, maintenance, and scrap of the motor, the effect of energy saving measures must be considered from the entire life cycle of the motor. In this regard, the main consideration is to improve efficiency in 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 testing technology to reduce the power loss of the motor, improve the efficiency of the motor, and design an efficient motor.
When the electric motor converts electrical energy into mechanical energy, it also loses a part of its energy. Typical AC motor losses are generally divided into three parts: fixed loss, variable loss and stray loss. Variable loss varies with load, including stator resistance loss (copper loss), rotor resistance loss, and brush resistance loss; fixed loss has nothing to do with load, including core loss and mechanical loss. The iron loss is composed of hysteresis loss and eddy current loss, which is proportional to the square of the voltage, and the hysteresis loss is also inversely proportional to the frequency; other stray losses are mechanical losses and other losses, including friction losses in bearings and fans, rotors Wait for wind resistance loss due to rotation.
Features of high-efficiency motors:
1. Save energy and reduce long-term operating costs. It is very suitable for textiles, fans, pumps, compressors, and can save motor purchase costs by saving electricity for one year;
2. Start the inverter directly or use the inverter to adjust the speed, and the asynchronous motor can be completely replaced;
3. The rare earth permanent magnet high-efficiency energy-saving motor itself can save more than 15% of electric energy compared with ordinary motors;
4. The power factor of the motor is close to 1, which improves the quality factor of the power grid without adding a power factor compensator;
5. The motor current is small, saving transmission and distribution capacity, and extending the overall operating life of the system;
6. Power-saving budget: Take a 55-kilowatt motor as an example. High-efficiency motors save 15% of electricity compared to ordinary motors. Electricity costs are calculated at 0.5 yuan per degree. Energy-saving motors can be used to recover the cost of replacing motors within one year.
Advantages of efficient motors:
Direct start and full replacement of asynchronous motors.
Rare-earth permanent magnet high-efficiency energy-saving motors can save more than 3% of electric energy compared with ordinary motors.
The power factor of the motor is generally higher than 0.90, which improves the quality factor of the power grid without adding a power factor compensator.
The small motor current saves power transmission and distribution capacity and extends the overall operating life of the system.
Adding the driver can realize soft start, soft stop and stepless speed regulation, and the power saving effect is further improved.
YE2-90 ~ 355 series (IP55) high-efficiency three-phase asynchronous motor is the latest development of a fully-enclosed self-fan-cooled squirrel-cage high-efficiency three-phase asynchronous motor. Efficiency of this series of motors
The index reaches the energy efficiency level 3 in China's GB18613-2012 "Energy Limit Values and Energy Efficiency Levels for Small and Medium-sized Three-phase Asynchronous Motors". YE2-90 ~ 355 series high-efficiency three-phase asynchronous motors have high efficiency and various performance indicators have reached the international advanced level. The motor is used to drive long-term running loads such as fans and pumps, which can save considerable power and help protect the environment.
YE2-90 ~ 355 series (IP55) high-efficiency three-phase asynchronous motors are installed in a size that meets the International Electrotechnical Commission's IEC72-1 standard. Motors with a center height of H160 and above are equipped with non-stop oil injection and drainage devices, and installation heat is reserved The space of the thermistor and moisture-proof heating belt is convenient for users to choose. The motor stator adopts F-level insulation, but the temperature rise is evaluated according to 80K, the motor temperature rise margin is large, and the life is long; the rotor adopts aluminum casting process, which has high reliability.
YE2 series high-efficiency three-phase asynchronous motor parameters:
Power range of this series motor: 0.75 ~ 315KW;
Frame height: H90 ~ 355
Enclosure protection grade: IP54, IP55, IP65
Case material: cast iron case (H80-355mm), cast aluminum case (H80-160mm)
Cooling method: IC411
Working mode: continuous working system (SI)
Power range: 0.75-315kw
Number of poles: 4, 6, 8
Rated voltage: 220 / 380V 230 / 440V 380 / 660V 400 / 690V;
Insulation class: F (stator temperature rise within 80K)
Rated frequency: 50Hz, 60Hz
Features of YE2 series high efficiency three-phase asynchronous motor:
High efficiency, low noise, low vibration, high starting torque, compact structure, novel design, beautiful appearance, convenient use and maintenance, etc. If the power is 3KW and below, it is the Y connection method. If the power is 4KW and above, it is the △ connection method. Ambient temperature: -15 ℃ ≤0≤40 ℃, altitude: no more than 1000 meters.
At present, energy and environmental protection are getting more and more attention. The electric power consumption of motors accounts for 70% of China's entire industrial power consumption and 50% of the country's total power consumption. Therefore, the motor industry has become one of the industries with the greatest energy saving potential. Actively promoting high-efficiency motors is the most important way to achieve motor energy saving.
The high-efficiency and energy-saving motor is to improve the design, materials and processes of ordinary motors, thereby improving energy utilization efficiency. According to China's motor energy efficiency standards, motor energy efficiency is divided into three levels: energy efficiency level one is an ultra-efficient motor, energy efficiency level two is a high-efficiency motor, and energy efficiency level three is an ordinary motor. Motor energy saving is divided into three modes according to the size of the motor: medium and large motors use system energy saving methods, micro motors use DC, frequency conversion and other technologies, and small and medium motors are mainly used in industrial fields to improve motor technology. Taking the most widely used small and medium-sized motors as an example, the current secondary energy efficiency is 87.5% -97.5%, and the efficiency of ordinary motors is 75% to 95%. High-efficiency motors are 1% to 10% more efficient than ordinary motors, which can reduce about 20% to 40% of power loss. Rare-earth permanent magnet high-efficiency motors completely save the excitation energy, and their energy efficiency is 10% to 15% higher than ordinary motors, which can reduce energy loss by more than 50%.
"Hero" sees the same, high efficiency and energy saving have become the consensus of the global motor industry development
The global motor is developing in the direction of high efficiency and energy saving, and the market prospect is very broad. The United States, Canada, Mexico, Brazil, Australia and New Zealand have successively established energy efficiency standards for electric motors. Such as the NEMAPremium ultra-high energy efficiency standard formulated by the United States on top of the EPACT standard, the EU's EU-CEMEP standard, the Australian AS / NS1359.5-2000, and the Chinese GB18613-2006 standard.
The "task" that must be completed-the only way for sustainable development
In October 2010, the Chinese government promised the world on the eve of the Copenhagen conference: by 2020, China ’s energy consumption per unit of GDP and carbon dioxide emissions will be reduced by 40% -45% compared to 2005. In March 2011, the "Twelfth Five-Year Plan" clearly stated that during the "Twelfth Five-Year Plan" period, China's GDP grew at an average annual rate of 7%, and energy consumption per unit of GDP and carbon dioxide emissions were reduced by 16% and 17%, respectively.
2020 target expectation "Eleventh Five-Year Plan" phased results "Twelfth Five-Year Plan" remaining target of "13th Five-Year Plan" is 40% -45% lower than 2005, down 19.1%, 16%, 11.7% -19.1%
To improve energy utilization efficiency and achieve the energy conservation and emission reduction targets smoothly, effective measures must be taken simultaneously in the three links of energy production, energy transmission and energy consumption. Electricity consumption accounts for about 50% of energy consumption, and motor power consumption accounts for half of the entire society. Therefore, improving the energy efficiency of motors will be an essential and important link in China's energy conservation and emission reduction policies. If all the ordinary motors in use are replaced with high-efficiency motors, the annual power consumption can be saved by about 66 to 110 billion kilowatt-hours. Under the same conditions, the entire country's power consumption can be reduced by about 2 percentage points. China's total energy consumption and energy consumption per unit of GDP have fallen by about 1 percentage point. Therefore, motor energy saving has become an inevitable way to achieve energy saving and emission reduction in China.
"Carrots and Sticks", the combination of subsidies and mandatory standards to accelerate the promotion of efficient motors in China
The "Twelfth Five-Year Plan" proposes vigorous development of seven strategic emerging industries, and the motor industry, as a leading industry in energy conservation and environmental protection, new energy, new energy vehicles, and high-end equipment manufacturing, must be strongly supported by national policies. The promotion of high-efficiency motors representing energy conservation and environmental protection will continue to increase.
In order to promote the promotion of high-efficiency motors, the state began to provide financial subsidies for high-efficiency motors on June 18, 2010; in order to achieve the goal of promoting 31.77 million kilowatts of high-efficiency motors in 2011, the subsidy level was increased on March 8 of the year, as shown in the following table:
In addition to increasing subsidies, the state has also continuously introduced mandatory policies to increase the promotion of high-efficiency motors. The "GB18613-2006" standard for the entire motor industry stipulates that since July 1, 2011, the motor industry has adopted the energy efficiency level two as a compulsory standard. Motors lower than the energy efficiency level two are not allowed to be produced and sold; in 2012, the Ministry of Industry and Information Technology issued The 12th Five-Year Plan for Energy Conservation of Industrial Systems was set. In this plan, the growth target of IE2 is set in 2015. The entire IE2 motor will reach more than 80% of the entire motor market. On March 16, the Ministry of Industry and Information Technology ’s website said The catalogue of obsolete electromechanical equipment is open for comments. The planned high-energy-consumption obsolete electromechanical equipment includes 135 items in 12 categories. This will accelerate the process of eliminating obsolete electromechanical equipment. The state adopts a combination of subsidies and compulsory measures to continuously improve motor energy efficiency standards and encourage the development of efficient and energy-saving motor markets.
Turning roads, bright future
Although the current promotion rate of high-efficiency motors is much lower than policy expectations. However, in analyzing the policies over the years, we can see that in the face of practical difficulties, the country's willingness to implement is getting stronger and stronger, and its determination is very firm. In the future, the trend of more enterprises adopting high-efficiency motors will not change, and the government's policy direction of vigorously promoting energy-efficient motors will not change.
Generally speaking, the market price per kilowatt of high-efficiency motors of the same specification is about 20% higher than ordinary motors, of which the price of rare earth permanent magnet high-efficiency motors is about 40% higher. However, from the perspective of the entire motor life cycle, the initial purchase, installation, and maintenance costs account for only about 10% of the total cost, and the electricity required for operation will account for about 90%. Choosing high-efficiency motors to save electricity costs is more in the long run.
From the point of view of the entire country, in 2011, the national electrical power consumption of motors exceeded 2 trillion kilowatt-hours. If all high-efficiency motors were used, the overall efficiency of the motor system could be increased by 3% to 5%, and annual power savings would be 66 to 110 billion kilowatt hours. Annual power generation at the Three Gorges Power Station. Based on an estimate of 0.6 yuan / kWh, the annual electricity cost savings are 39 to 66 billion yuan. Therefore, in the future, under the dual role of policy promotion and consideration of the company's own interests, huge demand for high-efficiency motors is bred.
