Permanent magnetic synchronous permanent magnet synchronous motor motor application prospect

Visible, dc thoughts have excellent authorized functions, its mechanical characteristics and speed

characteristics are parallel lines, this is the characteristics of all kinds of switch electric

thoughts have not. In addition, in fact, permanent magnetic iron remover. Dc current idea and

starting torque, high efficiency, speed control, good static characteristic features such as easily.

Good duty characteristics make dc thought for a long time before the 70 s, in the situation of speed

regulation, duty supplications, nearly became a unique selection. However, direct current (dc)

thought the authority of the fluff, the field winding on the stator attacks the main magnetic field,

the large dc power idea often also equipped with commutating ac electric motor parts

pole, in order to improve of the reversing of the motor function. Dc motor armature winding and been

planted on the rotor commutator, dc power supply through the brush and commutator will direct current

to the armature winding translates into alternating current in the armature winding, namely

mechanical current commutation. Tumultuous authority limit the dc thought to further reduce the

volume and weight, is double brush and commutator of the sliding contact caused by mechanical wear

and spark, the direct current idea obstacle, the more trustworthy authenticity is low, life is short,

cherish the maintenance of large amount of doing things. 

Commutation spark both the commutator of electric corrosion caused by nuisance source, or a radio will be harmless influence on the surrounding electrical equipment. Motor capacity, rotational speed is higher, the greater the subject becomes more important. So, in fact, permanent magnetic chuck. Ordinary direct current thoughts of brush and commutator limits the thoughts to burning with high speed, large capacity, depression and goods. On the switch power grid, people still usually manipulated exchange asynchronous electrical idea to drag xing machinery. Simple exchange asynchronous electrical thought has no authority, trustworthy real and long service life, low capital, cherish the simple maintenance. Compared with direct current (dc) idea, however, its speed control function is poor, small starting torque,

overload talent and low efficiency. Carnegie-give must be the onset of a rotating magnetic field from

the grid reactive power, so the power status is low, especially when the light load, which adds lines

and large power consumption. Permanent, since you know that a strong permanent magnet. Without beg

speed control of the situation, such as fan, water pump, the common machine tool drive, asynchronous

electric thought according to a leading fame, of course, this type of drag, visible in a large number

of energy wastage. Domain before the electric drive, rarely color synchronous electric thoughts,

learn to permanent magnetic iron remover. Its main cause motor fan is synchronous

electrical thought cannot under grid voltage starting, movement of the rotor pole under the effect of

rotating magnetic field, uniform torque is zero. They are also great frequency conversion power can

solve the starting and speed control of synchronous motor was thought subject, but in the 70 s,

variable frequency power supply of equipment are to think about. So, before the domain of electric

drive, using synchronous motor was thought as the original thoughts is seldom seen. In high power

within the boundaries, has no intention of occasional synchronous electric thoughts running example,

but it is often used to improve power factor of power grid enterprises.

The main technical points of the permanent magnet generator

1 magnetic circuit structure and the design calculation. The biggest difference between permanent

magnet generator and electrical excitation generator excitation magnetic field is that it is produced

by the permanent magnet. In permanent magnet motor is a magnetic source, and part of the magnetic

circuit. Magnetism of permanent magnet can not only associated with the manufacturing perkins diesel generator process of production, and also the shape and size of the permanent magnet, the magnetization machine capacity and the magnetization method, the specific performance data discreteness is very big. In motor and permanent magnet flux and provided by the magnetomotive force also varies with the magnetic circuit of the rest of the material performance, size and motor running state. In addition, the magnetic circuit structure of the permanent magnet generator is varied, leakage magnetic circuit is very complicated and the share of magnetic flux leakage is bigger. Part of the ferromagnetic materials and is easier to saturation, permeability is nonlinear. These have increased the complexity of the permanent magnet generator electromagnetic calculation, the accuracy of the calculation results under electrical excitation generator. Therefore, it is necessary to establish new design concept, to

improve the magnetic circuit structure and control system and analyze; Must be applied in modern

design method, the new methods of analysis and calculation, improve the accuracy of design

calculation; Must study the advanced test method and manufacturing process. 2 control problem. After

the permanent magnet generator is made electricalmotor1.blogspot.com without external energy can maintain its magnetic field, but also from external regulation, control of its magnetic field is extremely difficult. These make the application range is limited by the permanent magnet generator. 

But as MOSFET and IGBT power electronic devices such as the rapid development of control technology, can not control the magnetic field in the application of permanent magnet generator and motor output control, only when the design needs to be ndfeb material, three new power electronic devices and computer control technology, the permanent magnet generator run under new conditions. 3 irreversible demagnetization problem. If the design or improper use, the permanent magnet generator in high (ndfeb permanent magnet) or low (ferrite permanent magnet) temperature, under the effects of the armature reaction current impulse, or in severe mechanical vibration that may produce irreversible retreat (or called excitation-loss), reduce the motor performance, can't even use. Thus both the research and development is suitable for motor manufacturers use inspection of the permanent magnet material thermal stability of the method and device, and to analyze the structure of various forms of resistance to electric fan motor parts demagnetization ability, in order to make the design and manufacturing, to ensure permanent magnet generator with magnetic.4 cost problem. Because of the rare earth permanent magnet materials, the price is more expensive,the cost of rare earth permanent magnet generator generally higher than the electrical excitation generator, the need to use its high performance and operating cost savings to compensate. When the design should not only according to the requirements of specific use situation, performance, price comparison to choose, and must carry on the structure of the process of innovation and design optimization in order to reduce costs.

The asynchronous motor fault analysis

Due to the large motor current is too large and the change of supply voltage and single phase operation, mechanical, manufacturing bruised bad insulation damage caused by such as winding interturn short circuit, short circuit between windings, winding interelectrode interphase short circuit and winding short circuit. 1. The fault phenomenon Ion of the magnetic field distribution, unbalanced three phase current and make the motor vibration and noise when running, serious when motor can't start, and have great short-circuit current in coil of short circuit, lead to rapid heating coil and burned. 2. The reason Insulation insulation aging motor overload for a long time, lost; Wire insulation damage; Winding be affected with damp be affected with damp decreased insulation resistance caused by insulation breakdown; End and not cushion layer insulation material or plastic damage; End connection wire insulation damage; Or been struck by lightning overvoltage insulation breakdown; Friction between rotor and stator winding end insulation damage; Too many metal foreign bodies fall into the inside of the motor and oil pollution. Methods to examine

3. (1) the external observation method. Observation of junction box, winding end with or without burning, winding overheating after leave a dark brown, and has a bad smell. (2) temperature control method. No-load running for 20 minutes (found abnormal should immediately stop), with the back ac synchronous motor of hand touch winding parts is more than normal temperature. (3) the electricity experiment method. With current meter measurement, if one phase current is too large, magnet generator have indicated that the phase short circuit. (4) the bridge inspection. Measuring a winding dc resistance, general difference should not exceed 5%, such as more than small, resistance of a phase short circuit fault. (5) short circuit detection method. There is a short circuit the winding under test, the sheet steel can produce vibration. (6) multimeter or megohmmeter. And any two phase winding insulation resistance measurement, if the reading of the minimum or zero, shows that the two phase winding and has a short circuit. (7) voltage drop. After the three winding in series into the low voltage security alternating current (ac), the measured reading a group of small fault. (8) current method. Motor no-load running, to measure the three phase current, in two phase switch, measure and contrast, if he does not change with the power switch, a phase winding large current has the short circuit. 4. Short circuit processing method (1) the short circuit point in the end. Insulating materials available to separate short-circuit point, also can be double insulated wire, to paint drying. (2) short circuit online slot. After the softening, find out the short circuit point repair, back into the trough, then paint drying. (3) the short route turns less than 1/12 of each phase winding, the serial number of turns all cut short route, connect the conduction part, forming a closed loop, supply urgent use. (4) winding short-circuit point when www.facebook.com/dongfeng.motor the number of turns more than 1/12, to dismantle all rewind.

The connection method of three phase asynchronous motor

Three-phase asynchronous motor in the process of production, a lot of details to our attention. Including the working process of the three-phase asynchronous motor wiring and step has received the attention, now online side have a lot of articles on this subject. Now let's detailed discuss the three-phase asynchronous motor in the process of line to use the right way. When we are in the connection of the three-phase ac asynchronous motor, the connection method is connected into a triangular or the decision of the star can't out of thin air and calm, must operate according to the provisions of the manufacturer, as to the rules, we can very clear on the motor nameplate. And Settings, at the end of the three stator windings are displayed in the factory when the factory set in advance, we are in the process of operation will not appear upside down at the end of the first operation. Three-phase asynchronous motor wiring, main is to consider three of the motor stator winding of each group has two thread derivation, the two leads to the thread end is called the head end, while the other end of the end of the call. In the process of wiring, three sets of components of six wiring head can connect the three-phase winding become the shape of a star or the shape of a triangle. But y connection is the main three wire winding at the end of the parallel. The triangle; Connection method is mainly the first end of the first phase in the three-phase winding is connected with the end of motor fan the third water pump phase, after the connection access a phase power; And then the second head end connected with the end of the first, and then connected to a phase power; Finally, will the rest of the head end of the end of the second and the third to connect, completes the connection after connected to a power supply operation.

Large and medium-sized motor market prospect is very optimistic

Motor electric fan motor parts as an important device of electromechanical energy conversion, is the basis of the electric transmission equipment, a large number of used in fan, water pump, compressor, textile machinery, steel rolling
equipment, air conditioner and machine, printing machine, paper machine, the urban metro and rail transportation, lifting machinery, construction machinery and mining vehicle, to the national economy, energy utilization and electricalmotor1.blogspot.com environment protection plays a very important role. In general, large and medium-sized motor, quick speed, carrying heavy because of the large linear velocity, the basic use of thick-walled sliding bearing. Draws sliding bearing is one of the main products for China's large and medium-sized ac motor thick- walled sliding bearing, with the continuous development of large and medium-sized motor market, the demand of thick wall bearing will also increase. Provide broad space for development strategy draws
shares type. Undertake machinery equipment, bearings, hydraulic lift, investment promotion to join the industry such as network publicity,ac induction motor network promotion, press release, etc.

Small and medium-sized motor international standards

All kinds of motor factory in accordance with the national standard, according to the design and test data of the motor and regulation of the normal running state and conditions of each motor, called the rated operating condition of the motor. And characterization of the performance of the motor rated various values, such as voltage, current, power, etc. Is called the rating of the motor. For three-phase asynchronous motor under the specific meaning of these ratings, for your reference (in no particular order for each order, does not represent any meaning) : models. According to product performance, structure and USES the symbol rated power. The rated operating (refers to the voltage, frequency and current rating) case, the motor shaft output mechanical power to the rated power of the motor rated voltage. Motor under rated operating condition of the line ac induction motor voltage to the rated voltage of the motor. General provisions of motor voltage should not be higher or lower than 5% of the rating. Such as the three-phase stator winding can have two kinds of connection, with two corresponding rated voltage value. (if: when is higher than the rating voltage, excitation current will increase, iron losses increase, winding overheating phenomenon. When the voltage is lower than the rating, in the case of motor full load, will cause speed dropped, current is added, the winding overheating. 

Low voltage, maximum torque of the motor will be significantly reduced (1) rated current. Refers to the three phase asynchronous motor under the rated voltage, rated frequency and rated load is running, the line current in the three-phase stator winding, the unit is A. Due to the connection of the stator winding in a different way, rated voltage, rated current of the motor is also different. For example, a power rating of 10 kw three-phase asynchronous motor, its winding triangle connection, the rated voltage of 220 v, rated current is 68 a. Its winding star connection, the rated voltage of 380 v, rated current for 39 a. In other words, marked on the nameplate: connection - triangle/star; Rated voltage - 220/380 v. 68/39 rated current, a. (2) the rated speed. Refers to the motor under the rated voltage, rated frequency and rated load is running, the rotor revolutions per minute, the unit for r/min. Its value is slightly lower than the synchronous speed. (3) the rated frequency. Refers to the motor by the frequency of the ac power, our country power plant produces alternating current (ac), frequency of 50 hz. Reduce the frequency, speed, stator current increase. (4) connection. Refers to under the rated voltage of the motor stator winding connection mode. There are generally two motor part star and triangle connection. The y connection, connection of windings can withstand voltage is 1/3, square root of connection mode must be stipulated in the nameplate. Otherwise, the motor will be burned. 

(5) the insulation class. According to the insulation materials used in the winding, in accordance with its allowed heat degree level. Small and medium sized three-phase asynchronous motor insulation class has A, E, B, F and H class. The working temperature of the motor is mainly restricted by insulation material. If the temperature above the temperature of the insulating material is allowed to work, insulation aging quickly, it will shorten the service life. Repair of motor, the insulation of the chosen materials should comply with the regulations of nameplate insulation class. (6) work quota. Refers to the works of the motor, namely in the duration of the provisions under the working conditions of running or working cycle. Motor operation, according to the heating condition can be divided into three basic operation modes: continuous operation, short run and intermittent operation; Run continuously - the power of the running for a long time, as stipulated in the nameplate, such as the use of the water pump, fan and machine tool equipment on the motor way is continuous operation mode. The short run - time is only allowed within the stipulated time according to the rated power operation, and again before starting should conform to the provisions of the enough cooling time downtime. Intermittent operation - motor running in intermittent way, such as cranes and crane equipment with motor is intermittent operation mode respectively. The point at which the motor run for a long time continuously, the value of working temperature higher than the ambient temperature. Rules surrounding environment in our country the highest temperature of 40 ℃. If, for example, the permission of the motor temperature rise to 65 ℃, it allowed working temperature is 650 = 40 to 105 ℃. Without the permission of the motor temperature rise associated with grade insulating materials used. In operation of the motor temperature rise a great influence on the service life of insulation materials, theoretical analysis shows that in the operation of the motor insulation temperature higher than the rated temperature 8 ℃, its service life will be shorten half. 

(7) the rated power factor. Refers to under the rated output power of the motor, stator winding between phase voltage and phase current phase Angle cosine, about 0.70 ~ 0.90. Motor no-load running, the power factor of about 0.2 left again. The higher the power factor of motor, power distribution equipment utilization ratio, the higher the starting current. Refers to the current motor at starting moment, it is commonly used and the ratio of the rated current of multiples. The three-phase asynchronous motor starting current is usually 4 to 7 times the rated current. The rotor voltage. Wound rotor asynchronous motor stator winding with rated voltage, the voltage between the rotor rotates not two slip ring. Rated efficiency. (8) for motor, the input power and output power range, the difference is equal to the motor itself loss power, including copper loss, iron loss, mechanical loss and so on. Efficiency refers to the ratio of output power and input power, which is about (75 ~ 92) %. The higher the efficiency, the smaller the loss of the motor rotor current. Wound rotor asynchronous motor used in the rotor current rating. Starting torque. Starting torque is the point at which the motor starting torque, it is commonly used and the ratio of the rated torque multiples. Usually 1-1.8 times www.facebook.com/dongfeng.motor the rated torque. The weight. Refers to the weight of the motor itself, when lifting handling in order to offer reference.

Hot summer, the motor running problems should be paid attention to

In the operation of the motor in the hot summer work should pay attention to the following: 1, monitoring the power supply voltage change in voltage should not be more than or less than 10% of the rated voltage range, if lower than this range, should be appropriately reduced load operation. At the same time, the three-phase voltage imbalance also cannot too much. The difference of any two phase voltage should not exceed 5%, otherwise will make motor fever too fast. Motor power are best a voltmeter and switch directly to monitor. 2, monitors the running motor current Under normal circumstances operation shall not exceed the nameplate rating. Also should pay attention to whether the three phase current balance and any two interphase current difference should not be more than 10% of the rated current, otherwise the motor has a fault. Particular attention to whether there is a lack of phase operation. Shall furnish ammeter monitoring of large capacity motor running current, capacity should also be smaller motor line current is measured with a clip-on ammeter at any time. 3, monitoring the temperature of the motor The temperature rise shall not exceed allow the limits of the motor nameplate. In operation of the motor temperature rise is monitoring the motor running condition of direct and reliable way. 

Check the temperature rise method can refer to the 144 q. Online road furnish voltmeter, ammeter, and overload protection device, also is Motor vehicle the main way to monitor the temperature rise. 4, monitor the motor running in induction motor price the noise, vibration and smell when the motor running, voice even, smooth operation, insulating paint smell and the smell. In case of abnormal noise, vibration, insulating paint smell, etc., that motor overheating or other failures. 5, surveillance gear work To watch if there's any loose for pulley or coupling, transmission belt with and without sliding phenomenon (sliding belt is too loose), belt joint are in good condition. 6, monitor the condition of the bearing Pay attention to the bearing noise and fever. When using a thermometer to measure, rolling bearing heating temperature not over 95 ℃, sliding bearing heating temperature not over 80 ℃. Bearing abnormal sound or overheating, is poor lubrication bearing, wear and tear caused by severe. 7, monitor the condition of the fuse Should always pay attention to whether there is a photograph of blown fuse, lest cause lack of phase operation make the motor overheating. In a word, the motor in the process of running, monitoring the current, the change of temperature, found problems in a timely manner.