The energy saving project of the motor system has been listed as one of the 12 or 50 key energy-saving projects in China, and it is a key area for national energy conservation and emission reduction work. In March of this year, the Ministry of Finance and the National Development and Reform Commission confirmed at the national high-efficiency motor promotion work conference that the national high-efficiency motor promotion task in 2011 was 31.77 million kilowatts, accounting for about 30% of the domestic domestic motor sales. Low-voltage high-efficiency motor 20 million kilowatts, high-voltage high-efficiency motor 10 million kilowatts, rare earth permanent magnet motor 1.77 million kilowatts.
However, recently, some enterprises and industry experts have reported to the China Energy News reporter that there are many problems in promoting large-scale high-efficiency motors (355kw-25000kw) in China, including the reliability of efficiency tests, and the reliability of motor products that meet high-efficiency standards. It is not conducive to the expansion of China's overseas motor market. Our reporter launched an investigation and interview on this.
High-efficiency motors were first proposed by the American Electrical Manufacturers Association, but they only specified motors with powers below 367 kW. For large-capacity high-voltage motors, no country in the world, any standard tried to build a series of high-efficiency motors. An industry authority who did not want to be named told this reporter.
A number of industry insiders told this reporter that there are two main problems in large-scale high-efficiency motors: First, there is no scientific basis for the efficiency of high-efficiency motor efficiency, and second, third-party testing of efficiency cannot be implemented because of the large amount of motor. Consumers simply cannot determine whether the motor efficiency really meets the value of the manufacturer's test report.
According to our reporter, although most manufacturers will establish a standard series of large-capacity asynchronous motors, due to the variety of large-scale equipment and the particularity of the working conditions, the actual user directly selects the standard series of motors, even if the same Large-scale motors with power ratings often have large differences in motor performance requirements when ordering actual orders. Most orders require non-standardized designs. Relatively speaking, small motors are easy to serialize and generalize, and the above problems are no longer present. In order to determine whether large motors meet the requirements of high-efficiency motors, most motors are tested for efficiency each time. At present, the motor efficiency test value is generally determined by the enterprise itself, and the state does not have the conditions for all the third parties to measure the high-efficiency motor.
We have seen a two-pole motor with a high-efficiency motor mark on the use site, which uses a blower driven by a small motor mounted on the top to replace the fan on the rotor of the motor. However, when calculating the efficiency of the motor, they did not count the loss of the blower motor. This high-efficiency motor is obviously only efficient on paper. An electrical industry expert in China told this reporter.
There are no strict regulations on the calculation of high efficiency motor efficiency, and many users are also skeptical about the actual efficiency values that the motor can achieve. The above person said.
As far as manufacturing technology is concerned, Huang Guozhi, a professor-level senior engineer of the Shanghai Electric Apparatus College, told this reporter that the motor design technology is very mature. To improve the efficiency of the motor, the amount of effective materials such as copper and iron can only be increased to reduce The purpose of motor copper loss and iron loss. The capacity of large-capacity motors is very small due to the loss of power, and the efficiency of the motor is already high. The effect of increasing the amount of material to increase the efficiency of the motor is not obvious. The result is that the volume and weight of the motor are increased. The efficiency improvement is only a few tenths to one percentage point.