introductionofmotor

1、Introduction of motor Abstract Motor is a device that converts electrical energy into mechanical energy. It is through the coil (is the stator windings) generated rotating magnetic field and the role of forming a magnetic force rotating torque to the rotor (such as the mouse cage closed aluminum fra

2、me). Motor by using the power of DC motor and AC motor, motor power system mostly AC motor and can be synchronous motor or is asynchronous motor (motor stator magnetic field speed and rotor rotating speed does not maintain synchronous speed). The motor is mainly composed of stator and rotor, the dir

3、ection of the force movement in the magnetic field is related to the direction of the current and the direction of the magnetic field (magnetic field). The working principle of the motor is the effect of the magnetic field on the current force, which makes the motor rotate. Key words: Motor ; power

4、; magnetic field ;current Basic parameter Process of invention Motor using the pass electrical conductor in a magnetic field by the principle of force (this is different on the argument that the magnetic effect of electric current, the current teaching version of ninth grade physics clearly to separ

5、ate the two), found that this principle is the Danish physicist, OE, 1777 August 14, was born in Lange Ron Arudejobbin a pharmacist family. Admitted to University of Copenhagen in 1799, received a doctorate in 1794. From 1801 to 1803 to Germany, France and other countries to visit, met many physicis

6、ts and chemists. In 1806 he was appointed professor of physics at the University of Copenhagen, in 1815 he was appointed Permanent Secretary of the Royal Society of denmark. In 1820 due to current magnetic effect this extraordinary discovery by the British Royal Society Copley medal. Since 1829, he

7、served as president of the Copenhagen Institute of technology. Died in Copenhagen in March 9, 1851. He has studied physics, chemistry and philosophy in many aspects. Owing to the influence of Kants philosophy and the natural philosophy of Xie Lin, it is believed that natural forces can be transforme

8、d into each other, and to explore the relationship between electricity and magnetism in the long term. April 1820 finally found the current of the magnetic needle, namely current magnetic effect. In July 21st of the same year with the theme of the effect of electric needle on the conflict published

9、his findings. This short paper caused great shock to the European physics community, which led to the emergence of a large number of experimental results, which opened up a new field of Physics - a new field of physics. In 1812, he first proposed the idea of the connection between light and electrom

10、agnetism. In 1822, he studied the compressibility of liquids and gases. 1825 refined aluminum, but the purity is not high. In the study of acoustics, he tried to find out the electric phenomenon caused by sound. His last research work was magnetic. He is an enthusiastic attention to scientific resea

11、rch and experiment of the teacher, he said: I dont like the way that no experimental boring lectures, all scientific research from the beginning of the experiment of. So popular with students. He was also an excellent speaker and natural science popularization worker, in 1824, the establishment of t

12、he Danish Association for the promotion of science, created the first Danish physics laboratory. In 1908 the establishment of the association oersted Medal to promote the Danish Natural Sciences, in recognition of the significant contribution of physicists. Named 1934 unit of magnetic field in the C

13、GS unit to OE. 1937 American Association of physics teachers set up a oersted Medal, physics teacher reward to make a contribution in physics teaching. In 1821, Faraday completed the first major electric invention. In the past two years before, OE have been found if current passes through the circui

14、t, it in the vicinity of the ordinary compass needle will shift. Faraday was inspired by the thought that if the magnet is fixed, the coil may be moving. According to this idea, he succeeded in inventing a simple device. In the device, as long as there is current through the line, the line will turn

15、 around a magnet. In fact Faraday invented the first electric motor, which was the first device to use electric current to move the body. Although the device is simple, but it is today in the world to use the ancestors of all motors. This is a major breakthrough. But its practical use is very limite

16、d, because at that time there is no other way to generate electricity in addition to the simple battery. Development present situation Chinas motor production began in 1917, the industry has formed a relatively complete industrial system in the country. With the development of electric power industr

17、y, the electric motor manufacturing industry in our country has shown great vitality, and the scale of production and marketing and the economic efficiency have been greatly improved. 2005-2011 years, Chinas motor manufacturing industry sales revenue increased by an average of 36.92%. In addition to

18、 the affected by the financial crisis in 2009, general downturn in manufacturing, motor year-on-year growth rate fell to 11.20% outside, other years, the market size of Chinas motor growth rate are in high level, an average in more than 20%, even in 2011, Chinas manufacturing industry, the pace of d

19、evelopment of a general slowdown in under, motor year-on-year growth still reached 21.87%. Motor manufacturing enterprises should establish their own brands, the force of high-end, expand overseas markets, guarantee product quality and after-sales service, to the development of navigation, aviation,

20、 military industry, nuclear power and special motors, such as new areas, in order to in the fierce market competition in an invincible position. In the whole society electricity consumption, about 70% of consumption in the industrial field, and the power consumption of the motor industry and occupy

21、the entire industry of electricity 70%. To improve the efficiency of the motor can be mainly through 2 ways, through a frequency converter, AC motor to improve the operation efficiency; two is the use of high efficiency motors. The frequency converter is different such main industry, energy efficien

22、cy is more than 30%, in some of the industry even as high as 40%-50%. Efficient motor market application proportion is still relatively low, but the minimum energy efficiency standards and subsidies to support future efficient motor market application proportion will rise sharply. 2012 1-12 months,

23、Chinas total exports of electric motors and generators 3 billion 96 million units, compared with the same period in 2011 reduced by 8.2%, total exports amounted to $9 billion 224 million, an increase of 5%. The month of December, Chinas exports of electric motors and generators for 274 million 800 t

24、housand Taiwan, exports amounted to $818 million. In the investment, it should be before the introduction of favorable policies in advance layout. Efficient motor market applications are still low, but in the minimum energy efficiency standards and subsidies to support the future, the future efficie

25、ncy of the market will be a substantial increase in the proportion of motor market. The motor system comprises a control device, motor, drag device, transmission device and network load, is a complex system involving multidisciplinary and multi field. Strategic emerging industries, contract energy m

26、anagement policy, market-oriented energy-saving environmental protection service system construction, comprehensive utilization of resources and remanufacturing and energy-saving products Huimin engineering, motor is extended to the motor industry development has brought great opportunities, and the

27、 motor manufacturers and motor supporting enterprises also ushered in the renewal of product market growth potential. Especially in order to adapt to the low carbon economy era of energy saving technology innovation trend, high efficiency motor has gradually become the mainstream of the future marke

28、t. Chinas motor more than 2 trillion kwh electricity, accounting for about 60% of electricity consumption and industrial consumption 80%. High efficiency motor energy consumption than ordinary motor lower 20% 30%, but in our country, motor market share of only 10%, so vigorously promote efficient mo

29、tor will be for the country to promote energy-saving emission reduction has a certain significance, the potential market opportunities also emerging. Although there are many kinds of motor products in our country, but the efficiency is not high, there is a serious phenomenon of big horse drawn cart,

30、 and the promotion and application of high efficiency motors have no time to delay. Chinas Twelfth Five Year Plan period will concentrate around the motor system energy-saving projects, equipment manufacturing restructuring and revitalization, new energy technical field vigorously promote optimizati

31、on development of a group of highly efficient energy saving and environmental protection of key products, eliminated a number of general efficiency of motor products, to promote the upgrading of products. In the high energy behind the mechanical and electrical equipment ministry announced the (produ

32、ct) out of the directory (second batch), the electrical equipment list, indicating that Chinas motor industry will face a new development of the market and technology. To effectively eliminate inefficient motors, speed up the promotion of efficient motors, the National Standardization Management Com

33、mittee issued version of the small three-phase asynchronous motor energy efficiency limit value of energy efficiency and energy efficiency grades in the implementation of the national standard in September 2012, small motor industry faced with greater impact. At present, Chinas mass production of Y

34、, Y2, Y3 series three-phase asynchronous motor will be prohibited from production, enjoy the national Hui Min project YX3 series of high efficiency three-phase asynchronous motor will likely no longer receive policy subsidies. Efficient motor research and development and promotion is like the arrow,

35、 the industry is concerned about an unprecedented degree of attention. Startup mode Motor starting methods include: full pressure direct start, self coupling decompression starting, y- delta starter, soft starter, inverter. Full pressure direct start ： In the power grid capacity and load two are all

36、owed to direct starting pressure, total pressure can be used direct starting. Manipulation of advantage is easy to control, simple maintenance, and more economical. Mainly used for small power motor starting, from the point of view of energy conservation, more than 11kw of the motor is not suitable

37、to use this method. Self coupling decompression starting ： By using the multi tap decompression of the self coupling transformer, it can not only adapt to the need of different load starting, but also get a larger starting torque. It is a reduced starting method which is often used to start large ca

38、pacity motor. The biggest advantage is that the starting torque is larger, when the winding tap in 80%, the starting torque can reach 64%. And the starting torque can be adjusted by the tap. So far is still widely used. Y- Delta starting ： For the normal operation of the stator winding is connected

39、in a triangle method of squirrel cage asynchronous motor, if the stator windings are connected into a star at the start, after waiting for after the start and delta connected, you can reduce the starting current, and reduce its impact on the power grid. This starting method is called star delta deco

40、mpression starting, or short for star delta starting (y- delta starting). When starting the star delta, the starting current is the original 1/3. If the starting current is 6 to 7ie, the starting current is 2 to 2.3 times. This means that the starting torque is reduced to 1/3 when the starting torqu

41、e is directly started by the triangle method. Suitable for no load or light load starting. And compared with any other decompression starter, the structure is simple and the price is the cheapest. In addition, the star delta starting mode has an advantage, that is, when the load is light, the motor

42、can be operated in the star connection method. At this point, the rated torque and the load can be matched, so that the efficiency of the motor can be improved, and the power consumption is saved. Soft starter： This is the use of a phase shifted controlled silicon pressure principle to realize motor

43、 voltage starting, mainly used for motor starting control, start effect is good but the cost is high. Because of the use of SCR thyristor when the harmonic interference is large, has a certain impact on the power grid. In addition the grid fluctuations will also affect the thyristor conduction, espe

44、cially a plurality of controllable silicon in the same power grid equipment. So the SCR fault rate is higher, because it involves the power electronic technology, so the maintenance staff requirements are also higher. Frequency converter ： Inverter is the highest technology content in the field of m

45、odern motor control, control function of the most complete, the best control effect of the motor control device, which by changing the frequency of the power grid to adjust the speed and torque of the motor. Because it involves power electronic technology, computer technology, high cost, maintenance

46、 of technical personnel is also high, so it is mainly used in the need for speed control and high speed control requirements of the field. Speed regulating method A lot of motor speed control method, can adapt to the change of the speed of different production machinery. The general motor speed when

47、 the output power will change with speed. From the point of view of energy consumption, speed control can be roughly divided into two kinds: (1) Keeping the input power constant. By changing the energy consumption of the speed regulating device, the output power is adjusted to adjust the speed of th

48、e motor. (2) Control the input power of the motor to adjust the speed of the motor. Motor, motor, brake motor, variable frequency motor, variable speed motor, three-phase asynchronous motor, high voltage motor, multi speed motor, two speed motor and explosion proof motor. Structure classification Ba

49、sic structure 一 、 The structure of a three-phase asynchronous motor is composed of a stator, a rotor and other accessories. (一) stator (stationary part) 1、stator core Function: part of the magnetic circuit of the motor, and the stator winding is arranged on the motor. Structure: the stator core is m

50、ade of silicon steel sheet with insulation layer on the surface of 0.350.5 mm thick, which is formed by punching and laminating. There are several types of stator core slot ： Semi closed type slot ： motor efficiency and power factor is higher, but the winding embedding and insulation are more diffic

51、ult. Generally used in small low voltage motor. Semi open slot： can be embedded into the shape of the winding, generally used for large, medium and low voltage motor. The winding is winding can advance through insulating treatment and then into the groove. The opening slot: to embed the winding insu

52、lation, convenient method, mainly used in high voltage motor. 2、stator winding Function ： is the circuit of the motor, through the three-phase alternating current, generating a rotating magnetic field. Structure ： 120 in the space of each other three degrees electric angle, symmetrical arrangement o

53、f the structure of the same winding connection, the coils of these coils are embedded in the stator slot. The main insulation of the stator winding project has the following three kinds: (to ensure that the conductive part of the windings and the reliable insulation between the core and the reliable

54、 insulation between the windings). a、Ground insulation ： insulation between stator windings and stator core. b、Interphase insulation ： insulation between the stator windings of each phase. c、Turn to turn insulation ： insulation between turns of each line of each phase of the stator winding. Connecti

55、on in motor terminal box ： Motor terminal box has a wiring board, three-phase windings of the six thread arranged on two rows, and the provisions of row three wiring pilefrom left to right order number for 1 (U1), 2 (V1), 3 (W1), row three wiring pile from left to right order number for 6 (W2), 4 (U

56、2), 5 (V2). The three-phase windings are connected into a wye connected or connected in a triangle. Where manufacturing and maintenance should be in accordance with this sequence number. 3、seat Function: ： the fixed stator core and the front and back end cover to support the rotor, and the role of p

57、rotection, heat dissipation and so on. Structure: ： frame is usually cast iron parts, large asynchronous motor base general welding steel plate into, the miniature motor base used aluminum pieces. Closed type motor base outside the radiating ribs to increase the heat dissipation area, protection of

58、the motor frame at both ends of the end cover is provided with a ventilation hole, inside and outside the motor of air forced convection direct, to facilitate heat dissipation. (二) Rotor (rotating part) 1、Rotor core of three phase asynchronous motor ： Role: ： as part of the magnetic circuit of the m

59、otor and the rotor winding in the iron core slot. Structure ： the material used is the same as the stator, by the 0.5 mm thick steel sheet punching, lamination, silicon steel sheet with a uniform distribution of the hole, used to place the rotor winding. The stator core is usually used to flush the

60、rotor core with the inner circle of the silicon steel sheet which is backward in the stator core. The rotor iron core of the general small asynchronous motor is directly pressed on the rotating shaft, and the rotor core of the large and medium-sized asynchronous motor (rotor diameter is in 300400 mm