(armature) current and rotor coil current is the same? What is the relationship between them

The two are different.Coil current is branch current (ia), rotor current (ia) is more than the total

current branch. Branch of how many depends on the type of winding.In terms of single pile, shan bo

winding, the single lap winding of three phase generatora route.(2 a) is equal to the number of poles (2 p), namely Motor vehicle a = 2 p.Shan bo winding because has nothing to do with the number of magnetic poles, only two.Article 2 a = 2.So, shan bo winding rotor current Ia Ia = 2.After understand this, for the rotor.The cross-sectional area of.electricalmotor1.blogspot.com winding wire (guidelines) have a certain guiding role.

Delta connection of the motor and the difference between y connection

Under the small motor (4 kw) most using Y type connection, large motor usually adopt delta connection, star triangle decompression can also be used as a large motor starting, motor spare parts when starting torque motor coil Y type runtime is only half of the delta connection, but the current is only starting about a third of the triangle. Triangle when starting current is rated current of 4 to 7 times, but the torque is big. Speed is the same, but different torque For ordinary three-phase electricity, the phase voltage 220 v, line voltage 380 v. Y connection is three-phase power electricalmotor1.blogspot.com to one end of acmotortrading.blogspot.com each winding, the other three phase asynchronous motor end connect together. That each winding can gain phase voltage of 220 v. Delta connection is each winding end to end in order to form a triangle, three phase electricity in the Angle of the triangle. That each winding can gain line voltage of 380 v. If the phase voltage is 220 v, the rating of the motor is in y connection. If it is 380 v with delta connection. In particular, if the motor is belong to the rated voltage 380 v, you can use 220 v y connection step-down start, start to finish to switch to the delta connection

Y (IP44) three-phase asynchronous motor has the following good performance and structural features

(1) high efficiency level.Y series (IP44) small rotor three-phase asynchronous motor to keep the J02 series motor efficiency level is higher,the advantages of the weighted average efficiency is 0.413% higher than J02 series,Reached the international level.Due to the improvement of motor efficiency,has brought the huge power saving economic benefits to society.(2) the starting performance is better.Y series (IP44) motor series of locked-rotor torque than 33% higher than the average J02 series motor,starting torque reach JQ02 series high starting torque motor level,The minimum torque had guaranteed in more than 0.8 times the rated torque,and most also meet or exceed 1 times the rated torque.Therefore,the starting performance is very good,with load Starting is also very well.(3) low noise small vibration.Y series (IP44) audio power noise standards set by the three-phase asynchronous motor,according to the noise limit is divided into l and 2,for users to choose.Due to this series adopts special motor With bearing,thus greatly reduce running noise,checked by actual measured the noise lower than J02 series actual level for about 5-10

decibels,vibration is better than J02 series motor has decreased significantly.(4) the protective

performance is better.Y series (IP44) three-phase asynchronous motor's structure design has been

satisfied to the solid content and splash water protection requirements,so it can effectively prevent

the foreign body acmotor2.blogspot.com for motor and people The body of the damage.(5) the reliable running long service life.Y series (IP44) three-phase asynchronous motor's winding adopts class B insulation.When no more than 1000 meters above sea level,the temperature of the cooling centrifugal pump air is not more than 40 ℃,the motor Son of winding temperature rise limit method (resistance) less than 80 k.Therefore,in addition to a handful of electric motive specifications generally have more than 15 k temperature margin.The rise of temperature of the large margin can Extend the service life of motor and improve the reliability of the motor running.(6) beautiful appearance and easy.Y series (IP44) three-phase asynchronous motor end cover,connection Box cover,wind the appearance of main structure parts,such as older than traditional products to beautiful,generous.All series motor than J02 series volume shrink by an average of 15%,the average weight Reduce 12%.

Ac motor and dc motor

Ac motor and dc motor DC Motor (DC Motor) in the speed for the benefits of relatively simple, only control the size of the voltage has control of speed, but this kind of Motor is unfavorable in operating conditions such as high temperature, flammable, www.dongfeng-motor.com and due to the need to carbon brush Motor (am) as current converter components (brush Motor), so need to regular cleaning brush friction generated by dirt. Known as brushless motor without carbon brush motor, relative to the brush, because of less carbon brush and brushless motor shaft friction so more save electricity and quieter. Production difficulty is higher, the price also is higher. AC Motor (AC Motor), on the other hand, works under high temperature, flammable, and need not regular cleaning of carbon brush dirt, but in the speed is more difficult, because the control of AC Motor speed to control the frequency centrifugal pump of the alternating current (or the use of induction Motor, with increased internal resistance decreased under the same the frequency of the alternating current Motor speed), the control of the voltage will only affect the torque of the Motor. General household motor voltage of 110 v and 220 v two kinds, in industrial applications and 380 v 8500w gasoline generator or 440 v type.

Energy saving conditions

Energy-saving equipment technical conditions To draft This standard by the shandong province economic and trade commission, the bureau of quality and technical supervision of shandong province is put forward. This standard by the shandong energy standardization technical committee to review. motor spare parts This www.dongfeng-motor.com standard drafting unit: shandong province product quality supervision and inspection institute. Main drafter of this standard: Dong Jiang, Carolyn lau, Wang Feng, XinFeng, Lu Jinduo, Gao Jing, John rambo, Chen Hengliang Lin. Standard number: DB37 / T728-2007 The scope of This standard specifies the conditions of use of motor energy saving device, technical requirements, test methods, inspection rule, marks, packaging, transport and storage. This standard applies to rated voltage 660 v and below and rated current under 600 a and motor energy saving devices. Terms and definitions Energy-saving device: 1, the motor used in electric three phase asynchronous motor motor before input, control motor energy saving operation of electrical equipment (not including the inverter). 2, www.facebook.com/guohong.trading power saving rate in the same condition, the same time, the use of motor energy saving devices save electrical energy (kW · h) and not to use motor energy saving devices use electricity (kW · h) ratio, expressed as percentage. Conditions of use 1) : the elevation 1000 meters, and the following; 2) ambient temperature: 0 ℃ ~ + 40 ℃. 3) relative humidity: 90% or less (+ 25 ℃); 4) no serious damage to insulation and corrosion of metal in the air gas, conductive dust and flammable and explosive medium.

Ac servo motor control

The structure of the dc servo motor as the common dc motor, and is done in order to reduce the moment of inertia of long and thin. It's exciting winding and armature respectively by two independent power supply. There is also a permanent magnet, namely the pole is a permanent magnet. Usually adopt the armature control, that is, f certain excitation voltage, establish flux Φ is also a constant value, and the control voltage in the armature Uc, institutional characteristics of the dc servo motor (n = f (T)) and dc separately excited motor, three-phase asynchronous motor under different control voltage (Uc control voltage rating) of mechanical characteristic curve. By the graph is: under certain load torque, when magnetic flux unchanged, if the rise in the armature voltage, the electric vehicle motor speed of the motor is higher; On the other hand, the lower the armature voltage, speed dropped; When Uc = 0, motor immediately halt. To motor reversal, can change the armature voltage polarity. Compared with dc servo motors and ac servo motor, it has mechanical properties is stiff, the output power is larger, rotation, large starting torque, etc The normal operation of the servo motor, as long as out of control voltage, the motor stop immediately. When servo motor loss control voltage, it is in single phase operation state, due to the rotor resistance is big, the rotation of the two opposite directions in the stator rotating magnetic field and rotor effect produced by the two torque characteristics (T1, T2 S1 S2 curve) and synthetic torque characteristics (t-s curve, with the ordinary single-phase asynchronous motor torque characteristics (T '-s curve). Then the synthesis of torque T is the brake torque, so as to make the motor stop quickly. Servo motor is single-phase runtime mechanical characteristic curve. 

A certain load, the control voltage Uc, the higher the speed is higher, in the control voltage, load, speed down. The structure of the ac servo motor stator is basically similar to capacitance split-phase single-phase asynchronous motor. On the stator winding with two position difference of 90 ° to each other, one is Rf excitation winding, it always pick on the ac voltage Uf; L, another is the control winding connection control signal voltage Uc. So is also called the two ac servo motor servo motor. wholesalemotor.blogspot.com Hollow cup rotor servo motor structure without control voltage ac servo motor, the stator is only produced by the pulse excitation winding magnetic field, rotor motionless. When a control voltage, stator and then produce a rotating magnetic field, the rotor rotate along the direction of the rotating magnetic field, in the case of constant load, the speed of the motor changes with the size of the control voltage, when the control voltage of opposite phase, servo motor will be reversed. The output power of the ac servo motor is 0.1 100 w. When the power supply frequency 50 hz, voltage is 36 v, 110 v, 220, 110 v; When the power supply frequency is 400 hz, the voltage have 20 v, 26 v, 36 v, 115 v, etc. Ac servo motor smooth operation, low noise. But control characteristic is nonlinear, and the rotor resistance is big, loss is big, efficiency is low, so compared with capacity of Y series motor, big volume, heavy weight, so is only applicable to 0.5 100 w small power control system. The working principle of ac motor fan servo motor with split-phase single-phase asynchronous motor, though similar, but the rotor resistance of the former is much larger than the latter, so compared with the single asynchronous motor, servo motor has three significant characteristics, due to the rotor resistance is big, the torque characteristic curve 1, with normal asynchronous motor torque characteristic curve, compared to 2 a significant difference between the two. It can make the critical slip S0 > 1, this not only makes the torque characteristic closer to linear mechanical properties, and has a large starting torque. Therefore, when the stator's a control voltage, rotor rotating immediately, which has the characteristics of starting fast, high sensitivity. The rate in the range of 0 to 1 S servo motor can stable operation.

The application of soft start the motor?

Widely used in coking production process equipment such as fan, water pump, and belt conveyor, generally need to directly under overloading starting motor, starting current is as high as 8 =; Times, power electric fan motor parts supply network voltage drop is too large, to be the impact of the driven equipment and control equipment failure rate is high. To solve the problem of high power motor start-up, generally USES the frequency-sensitive rheostat, since the lotus root transformer, B C % perkins diesel generator conversion and yanbian triangle startup mode, etc. But the traditional way of step-down start widespread starting equipment complex, small starting current and starting torque, etc. And the operation of the protection in motor, there are imperfect or insensitive. In recent years, with the development of power electronics technology and its related devices, three-phase asynchronous motor soft start technology has become increasingly perfect, and has been widely used. Soft starter is composed of microprocessor and high power thyristor, with microprocessor control thyristor conduction Angle, to control the output voltage. Therefore, the soft starter is actually can automatically control the step-down starter. Because you can adjust the output voltage and current closed-loop control, so be better than the series resistance and autotransformer such as traditional step-down starting way. 

And the failure rate is higher, the startup current impact on motor is extremely adverse. 3, soft starter start Soft starter starts, not only the operation is simple, and can be obtained from the motor initial starting torque, starting voltage can be increased. Selects the kick start function, can provide big promotion for motor torque, in order to overcome the inertia of load and quickly complete the boot process, the actual starting time of 261. By drum machine cold section in the practical application showed that the circulating water pump motor soft start technology not only can provide flexible start mode and excellent start features, can also provide soft start, soft start of belt optional kick start, current-limiting starting, double ramp up and started full pressure, etc. In addition, can provide various operations of protection, fault conditions directly read operation parameters www.dongfeng-motor.com of the motor, fault self-diagnosis function, with stepless regulating switch to eliminate the system of contact. Humanized menu interface can easily access or modify the parameters, to achieve centralized control through additional communication network interface. Also can effectively reduce the startup of mechanical stress, reduce the impact to mechanical transmission components.

Controlled operation of brushless dc motor electrical engineer

Brushless dc motor (BLDCM) is in a brush dc motor on the basis of development, but its drive current

is a standard form of communication; Brushless dc motor and can be divided into rate of brushless

motors and brushless torque motor. Generally, there are two kinds of brushless motor drive current,

one kind is trapezoidal wave (usually "square"), the other is a sine wave. Sometimes called before a

brushless dc motor, the latter is called ac servo motor,www.dongfeng-motor.com
exactly is a kind of ac servo motor. General electrical engineer brushless dc motor in order to

reduce the moment of inertia, usually adopts the structure of "thin". Brushless dc motor on the

weight and volume than a much smaller brush dc motor, the corresponding moment of inertia can be

reduced by 40% - 50%. Because of the permanent magnetic material processing problems, the brushless

dc motor general capacity are below 100 kw. That the mechanical properties of the motor and

regulating characteristics of good linearity, wide speed range, long service life, convenient

maintenance noise small, does not exist a series of problems caused by brush, so this kind of motor

in the control system has great application potential. The stator winding of the motor to make more

balanced three-phase y connection, with three phase asynchronous motor is very similar. On the rotor

of the motor with the magnetization of the permanent magnet has, in order to detect the polarity of

the motor rotor, inside the motor is equipped with position sensor. Drive consists of power

electronic devices and integrated circuit, its function is: accept the motor start, stop, brake

signal, to control the motor start, stop,www.facebook.com/guohong.trading
and the brake; Accept the position sensor signals and positive &negative, used to control the

inverter bridge on and off of each power tube produce continuous torque; Accept the speed instruction

and speed feedback signal, which is used to control and adjust the speed; To provide protection and

display, and so on. Because of brushless dc motor based on self-control type operation, so don't like

frequency control of motor speed synchronous motor overload start under plus startup winding on the

rotor, also won't generate oscillation and step out when load mutation. Medium and small capacity of

the permanent magnet brushless dc motor (BLDCM), now more than using high magnetic energy product of

rare earth ndfeb material (Nd - Fe - B). As a result, the volume of rare earth permanent magnet

brushless motor than three-phase asynchronous motor with capacity reduces a frame number. General

electrical engineer pointed out that nearly 30 years study of asynchronous motor frequency control of

motor speed, in the final analysis is looking for a way to control the asynchronous motor torque,

rare earth permanent magnet brushless dc motor is bound to its wide speed range, small motor

fanvolume, high efficiency and steady speed water pump and small error

characteristics appeared in the field of speed advantage. For brushless dc motor has the

characteristics of a dc motor, is also the device of frequency variation, so also known as dc

frequency conversion, the international general term for BLDC) motors running efficiency of the

brushless dc motor, torque at low speed, precision of speed is more good than any of the control

technology of inverter, so the industry concern. This product has production more than 55 kw, can

design to 400 kw, can meet the requirements of industry energy saving and high performance drive.

The motor of moisture-proof and baking

Due to the pumping station built in low-lying areas liable to waterlogging, more commonly in poorly

ventilated, drizzly conditions can easily be affected with damp be affected with damp, even suffering

from flood. Once the motor be affected with damp be affected with damp, when the voltage to be

affected with damp be affected with damp in the motor coil, it is easy to cause the breakdown of coil

winding and burning motor. So, even if used to dry the good motor, after stopping for a long time,

before start closing ventilation with full voltage current, must strictly check the windings of be

affected with damp be affected with damp. Examination method is the most commonly used high

resistance meter (that is, the shaking table) measuring insulation resistance and absorption ratio

(i.e. the insulation resistance R in 60 seconds to 15 seconds when the ratio of the R60 / R15). Motor

winding high efficiency three phase electric motor sinsulation resistance involves many factors, can be used commonly in practice the following standards: motor stator winding insulation resistance work every 1 kv voltage not less than 1 megohm; Rotor winding insulation resistance value not less than motor part 0.5 ohms. Usually below 500 v motor stator winding insulation resistance value not less than 0.5 ohms. 

More than 1000 v motor must absorb the measure, its value according to the rules should be followed: R60 / R15 1.3 or higher If cannot meet this requirement, he must to dry the motor. Commonly used methods for motor drying process with external drying, current drying and combined drying method of both. (a) outside to dry Namely the use of external heat source for dry processing, commonly used measures are: 1. Waft hot: using equipped with electric heaters of blower waft hot air drying process in order to achieve the purpose of; Baking: 2. The bulb in the sealed box, the use of a number of around 200 w bulb for baking, as well as around the motor for baking, can also be unwrapped motor, put the light bulb in the stator hole for baking. Baking heat infrared light bulbs or infrared thermal pipe may be adopted. It should be pointed out that baking temperature overheats, especially hole baking, motor stator winding of the damage caused by high temperature easy. Conditional situations can be baked with temperature control technology. Baking temperature control in less than 125 ℃ advisable. (2) current dry Also known as internal drying or short circuit drying. According to the size of the impedance of the motor and the

power supply to the motor three-phase winding in series or in parallel, then access a variable

resistor, adjust current to about 60% of the rated current value, electricity to dry. Note: by water

soak dry method cannot adopt the motor current, external drying should be adopted, or scope of the

external drying method is adopted to safety first, www.facebook.com/dongfeng.motor then

combined with the current drying method is adopted.

Motor selection guide

Mechanical motor selection directly affects the operation efficiency and service life of the machine, so choose a reliable motor manufacturer product is crucial to its roughly may refer to the following aspects: Voltage and frequency; Domestic voltage grade of 6 kv + - 5%, the power supply voltage within ac induction motor the scope of this change does not affect the performance of the motor parameters. Level of domestic frequency 50 hz + - 2%, power frequency within the scope of this change does not affect the performance of the motor parameters. Motor installation location, high altitude and working environment temperature; < > rotary motor norm and performance stipulated in GB/T755 able motor installation location is not higher than 1000 m above sea level, is not higher than 40 degrees Celsius temperature environment. If the installation environment does not exceed more than the environment can be carried out in accordance with the standard data operation, if more than the above range of the motor output, generally less than the power of the sample, contact the ac motor electric 65kw manufacturer. Choose according to environment protection grade; Cement plants, flour mills, mining and other dust field should be more choose IP55 / IP54 products; Environment better no dust occasions to select IP23 / IP44 products. And if there is a protective measures should be considered when outdoor use and prevent the combining practical considerations such as canopy product protection grade. The load of the motor types; Usually a fan, water pump, compressor, machine load appropriate chooses squirrel-cage motor, ball mill, crusher, mill type appropriate chooses type motor. If you need speed regulating motor according to the speed control mode or speed, such as feedback motor, frequency conversion motor, etc. Often use squirrel-cage motor load is light, general selection around the linear motor in the load. Motor auxiliary equipment. Can consider cold wind power, space heater, temperature measuring element (our configuration for high voltage motor temperature measuring element, please information sima in shaanxi province jindu motor www.dongfeng-motor.com co., LTD.), current transformer, thin oil station (our stand number more than 500 and 710 stand above the 2 pole motor motor basically equipped with pressure circulating oil lubrication sliding axis), vibration components, etc

The working principle of numerical control instrument lathe

Numerical control instrument lathe using fast clamping collet chuck, direct drive power electric motors spindle motor, the size of the disc quickly operating lever type, the vertical and horizontal to the positioning control turning, part of the instrument lathe with the installation of flange, tailstock, die with threading device, can processing and outer circlea and inner circle, cutting, end face, cutting groove, tapering, drilling, reaming, tapping screw, milling, grinding, etc. Widely used in electrical electric motor cooling fan appliances, fasteners, automotive, motorcycle accessories, instruments and meters, hardware appliances, stationery, film and television equipment, mechanical and electrical products, plumbing pipe fittings, valves, bearing ring, axial and other small parts, glasses manufacturing production and processing, and other small workpiece is the most ideal high-efficiency equipment hardware machinery processing industry. Because use hand push feed, fast clamping collet chuck, plunger type limit device, a quick hand plate, motor direct drive spindle running, turning, positioning control of a single continuous processing fixed kinds of artifacts and appearance, and improve working efficiency 10 times more than ordinary lathe, especially suitable for large quantity, small parts processing. But instead of other machine tools, to save the energy.

Three-phase asynchronous motor connector

A change, triangular connection motor y connection Normal operation by delta connection of three-phase asynchronous motor, in order to reduce power use, can take three phase electric fan motor parts windings into star after online on the power supply voltage of 380 v, about 34% of the rated power is the power of the motor. For example, the 380 v delta connection 10 KW three-phase asynchronous motor to change into a star, meet online voltage of 380 v three-phase power use, at this time the power output of the motor is about 3.4 KW. Second, the three-phase asynchronous motor single-phase asynchronous motor Y connection and delta connection of three-phase motor changes the same way. Open the three-phase asynchronous motor terminal box, between any two phase power terminal access to a capacitor. The capacitor between V1 and W1, for example, it is at this point to connect single-phase power supply between the U1 and V1 or W1 (assuming the power of connect between the U1 and V1 motor, the power supply in U1 and electric opportunity inversion between W1,) can transform the original three-phase asynchronous motor converted a single-phase asynchronous motor. This method is especially suitable for no occasion of three-phase power supply using three-phase asynchronous motor. The capacity of the capacitor C = KP obtained are available, and where C is the capacity of the capacitor, the unit is the micro method (u F); P is the power of the motor, the unit is a kilowatt (KW); K is the empirical coefficient, take 0.06 when y-connection three-phase asynchronous motor, triangle sexual connection for 0.1. For example, 10 kw three-phase asynchronous motor when the star connection KP = C = 0.06 x 10 = 0.6 u F; 10 kw three-phase asynchronous motor triangle connection KP = C = 0.1 x 10 u F = 1. Changed to: after instead www.dongfeng-motor.com of capacitor terminals, such as the case of U1 power cord, another power cord by V1 connector on the W1 can realize inversion, the inversion of the inversion principle of single-phase asynchronous motor with the same principle Connect power: after the change is a single-phase capacitance motor, its effective power is 70% of the original motor power, for example: 10 kw three-phase asynchronous motor connector into effective power single-phase capacitor motor is about 7 kw. Convert into single-phase capacitor start motor, its effective power is 40% of the original asynchronous motor motor power, for example: 10 kw three-phase asynchronous motor connector into effective power for 4 kw single-phase capacitor start motor. To pick up after each phase winding voltage for no more than the rated voltage of the winding. What kind of motor depends on specific convert into being dragged the power of agricultural machinery. When convert into single-phase capacitor start motor, need to add one more time relay, wiring method is: put the time delay of time relay to disconnect the instantaneous closure in series capacitor circuit, the normally closed contact of time relay coil in parallel on both ends of single-phase power supply (time relay coil of the rated voltage is the same as the power supply voltage). After connected circuit, adjust the delay time of time relay, can work normally. Its working principle is: when switched on, time relay and motor for electricity at the same time, the capacitor circuit switched on, the motor starts, when the speed reached about 80% of the rated speed (implementation) by adjusting the delay time relay time delay disconnect instantaneous closure of time relay normally closed contacts disconnect, cut off the capacitor circuit, motor function.

The application of soft start the motor?

Widely used in coking production process equipment such as fan, water pump, and belt conveyor,

generally need to directly under overloading starting motor, starting current is as high as 8 =;

Times, power supply network voltage drop is too large, to be the impact of the driven equipment and

control equipment failure rate is high.www.facebook.com/dongfeng.motor To solve

the problem of high power motor start-up, generally USES the frequency-sensitive rheostat, since the

lotus root transformer, B C % conversion and yanbian triangle startup mode, etc. But the traditional

way of step-down start widespread starting equipment complex, small starting current and starting

torque, etc. And the operation of the protection in motor, there are imperfect or insensitive. In

recent years, with the development of power electronics technology and its related devices, three-

phase asynchronous motor soft start technology has become increasingly perfect, and has been widely

used. Soft starter is composed of microprocessor and high power thyristor, with microprocessor

control thyristor conduction Angle, to control the output voltage. Therefore, the soft starter is

actually can automatically control the step-down starter. Because you can adjust the output voltage

and current closed-loop control, so be better than the series resistance and autotransformer such as

traditional step-down starting way. Drum cold section in our factory now chiller water circulating

pump motor as an example, the motor power < 95 DE, rated current 755 f, rated voltage 7 > 56, 755

(power lines, cable main section < 45 (4 pairs of power supply and the main transformer capacity <

555 d6f, motor overload starting. 1, the total pressure directly By the relevant calculations,

short-circuit capacity of power motor part system bus voltage drop in 437, the motor terminal voltage is the voltage of 89: left and right sides, directly below the motor starter needed; 6: the requirement of the terminal voltage, hard to conform to the requirements of the launch, it must adopt step-down start. 2, autotransformer step-down start Calculation result is: the < = > 3? ; 3 @ 7 a, B = * > 3? 29 the C7, B = > 3 D? "2" "C7E F = >" 351.

Using autotransformer buck up, there is the startup time is too long, start the difficulty and the

need to increase a step-down starting set of problems. And the failure rate is higher, the startup

current impact on motor is extremely adverse. 3, magnet generator  soft starter start Soft starter starts, not only the operation is simple, and can be obtained from the motor initial starting torque, starting voltage can be increased. Selects the kick start function, can provide big promotion for motor torque, in

order to overcome the inertia of load and quickly complete the boot process, the actual starting time

of 261. By drum machine cold section in the practical application showed that the circulating water

pump motor soft start technology not only can provide flexible start mode and excellent start

features, can also provide soft start, soft start of belt optional kick start, current-limiting

starting, double ramp up and started full pressure, etc. In addition, can provide various operations

of protection, fault conditions directly read operation parameters of the motor, fault self-diagnosis

function, with stepless regulating switch to eliminate the system of contact. Humanized menu

interface can easily access or modify the parameters, to achieve centralized control through

additional communication network interface. Also can effectively reduce the startup of mechanical

stress, reduce the impact to mechanical transmission components.

Three-phase asynchronous motor speed control application

Widely used three-phase asynchronous motor, but after running through a long time, can produce all kinds of fault, determine the cause of the problem in time, the corresponding processing, is to prevent failure, ensure the normal operation of equipment is an important work. A, after electrify motor does not turn, then fuse 1. The cause of the problem (1) the lack of a power supply, or set the main circle a contrary; (2) and stator winding short circuit; (3) of the stator winding grounding; (4) of the stator winding wiring error; (5) fuse section is too small; 5. The power cord short circuit or grounded. 2. The troubleshooting (1) to check whether there is a knife switches are not good, can be a phase break power supply circuit; Eliminate the reverse fault; (2) find out short circuit point, repair; 3. Eliminate grounding; (4) detected misconnection, be corrected; 5. Replace the fuse; (3) to eliminate ground point. Second, l. the cause of the problem (1) set, rotor winding circuit (a break) or loss of electric power supply a photograph; (2) winding lead beginning end wrong or winding inside the; (3) the power supply circuit of loose contact, contact resistance; (4) the motor load is too large or rotor stuck; (5) the power supply voltage is too low; 6. Small motor assembly is too tight or bearing grease is excellent; All landowners bearing stuck. 2. Troubleshooting (1) find out the breakpoint repair; (2) check the winding polarity; Judge winding ends is correct; (3) fastening screw loose connection, use the multimeter judge whether each joint false, repair; (4) the lightening or detect and eliminate the mechanical failure, (5) check also is the surface connection misconnection Y; Whether due to the large power supply wire carefully make the pressure drop, corrected, 6 reassemble makes it flexible; Replace the qualified grease; All landowners to fix the bearing. 

Four, after electrify motor cannot turn, but no ring, no peculiar smell and smoke 1. The cause of the problem (1) the power did not pass (at least two phase flux); (2) the blown fuse (at least two mutually fusing); (3) overcurrent relay adjusted too small; (4) control equipment connection errors. 2. The troubleshooting (1) check the power supply circuit switch, fuse, junction box, is there a breakpoint, repair; (2) check the fuse model, fusing the reason, a new fuse; (3) regulating relay setting value and motor coordination; (4) correct wiring. Third, the motor starting difficulty, rated load, motor speed is lower than the rated speed 1. The cause of the problem (1) the power supply voltage is too low; (2) the surface connection motor misconnection Y; (3) the cage rotor welding or fracture; (4) stator coil of local pick up, pick up the wrong; (3) increase the number of turns when repair motor winding too much; (5) motor overload. 2. The troubleshooting (1) to measure the power supply voltage, trying to improve; (2) the correct connection; (3) check the open welding and breakpoint and repair; (4) found it by accident, shall be corrected; (5) to restore the correct number of turns; 6. Lightening. After electrify motor does not turn a hum Five, motor racing, load, ammeter pointer instability, oscillation Article 1. The cause of the problem (1) the cage rotor guide open welding or broken; (2) wound rotor fault (a circuit) or poor contact brush, collector ring short circuit devices. Article 2. The troubleshooting (1) find out fault repair or replacement of the rotor; (2) check and repair wound rotor circuit. Six, motor no-load current imbalance, phase difference is big 1. The cause of the problem (1) the rewind, stator three phase winding circle number not equal; (2) the first end winding wrong; (3) the power supply voltage imbalance; (4) there winding interturn short circuit and coil reverse fault. 

2. The troubleshooting (1) to make child winding around; (2) check and correct; (3) to measure the power supply voltage, trying to eliminate imbalance; (4) forms in addition to the winding faults. Seven, motor running noise is not normal, there are sound 1. The cause of the problem (1) the rotor and stator insulation paper or slot wedge facies; (2) oil bearing wear or with sand and other foreign body; (3) loose stator iron core; (4) bearing oil shortage; (5) to fill or brush wind hood fan, air duct and stator iron core facies; All landowners supply voltage is too high or not balance; End of the stator winding fault or short circuit. 2. The troubleshooting (1) clip insulation, low cutting slot wedge; (2) replace bearing or cleaning bearing; (3) maintenance and repair, motor parts the rotor iron core; (4) come on; 5. Clean up the air duct; Reinstall the place; 6. Remove the scratch, when necessary, the car small rotor; 7) check and adjust the power supply voltage; The stator windings faults was eliminated. Eight, the number of motor vibration in the operation of the larger 1. The cause of the problem (1) due to wear and tear bearing clearance is too large; (2) uneven air gap; (3) the rotor unbalance; (4) shaft bending; (5) core deformation or loose; 6. Coupling (pulley) center is not correct; All landowners fan imbalance; Today casing or base strength is not enough; Pet-name ruby motor loose bolts; Attending open cage rotor welding circuit; Wound rotor circuit; The stator winding fault. 2. The troubleshooting (1) repair the bearing, if necessary, to replace; (2) adjust the air gap, and make it evenly; (3) correction of rotor dynamic balance; (4) straightening shaft; Calibration overlapping iron core (5), 6 to correction, to comply with the rules; All landowners overhaul fan, balance correction, correct its geometry shape; Today to reinforce; Pet-name ruby fastening bolts; Attending to repair the rotor winding; The repair of the stator winding. Nine, motor no-load current balance, but value is big 1. The cause of the problem (1) to repair, the stator winding turns to reduce too much; (2) power supply voltage is too high; (3) Y after motor misconnection Δ; (4) in the motor assembly, rotor installed backwards, making the stator core unaligned, effective length cut short; (5) the air gap is too large or uneven; 6 overhaul when the demolition of the old winding, using hot tear open method is undeserved, make the iron core loss. 2. The troubleshooting (1) rewind stator winding, restore the correct number diesel generating set of turns; (2) managed to restore rated voltage; (3) to connect to Y; (4) to assembly; (3) to replace the new rotor or adjust the air gap; (5) maintenance core or recalculate winding, appropriately increase the number of turns.

Motor winding embedded line maintenance

Wound rotor motor is a class of asynchronous motor. Asynchronous motor is according to the rotor winding form, divided into wound rotor and cage. The working principle of asynchronous motor is when the three-phase stator winding of the motor (the difference between 120 degree Angle), after the ventilation with balanced three-phase alternating current (ac), will produce a rotating magnetic field, the rotating magnetic field cutting rotor winding, thus produce induced current in the rotor winding, rotor winding is closed path), the rotor of current-carrying conductor under the effect of the stator rotating magnetic field will produce electromagnetic force, as to form the electromagnetic torque on the motor shaft, drive motor rotation, and the motor rotating direction and rotating magnetic field in the same direction. So the asynchronous motor is also known as induction motor. 1 composition and the function Three-phase asynchronous motor consists of stator and rotor two rotor cutting machine basic parts. Is the fixed part of the motor stator, to produce a rotating magnetic field, mainly by the stator core, stator winding and base parts. The rotor is rotating part of the motor, the rotor iron core and rotor winding and the rotor parts, its effect is obtained rotational torque under the action of a rotating magnetic field. Different rotor according to its structure is divided into squirrel cage rotor and rotor winding. Two basic characteristics and USES asynchronous motor Asynchronous motor mainly used as a motor. It is the industrial and agricultural production permanent magnet motors for sale and the most widely used in national economic sectors and demand one of the biggest motor. 

Metal cutting machine tools, steel rolling equipment, air blower, grinder, water pump, oil pump, light machinery, textile machinery, mining machinery, etc., the vast majority USES the asynchronous motor drive. In people's everyday life, the application of the asynchronous motor is increasingly widely, such as electric fans, washing machines, refrigerators, air conditioning and other household electrical appliances, the use of single-phase asynchronous motor. Drag motor for electric drive, the vast majority of asynchronous motor, its power consumption accounts for about 60% of the total load of power grid. Asynchronous motor is widely used because it has a simple structure, convenient use, reliable operation, high efficiency, and easy, low cost, etc. Asynchronous motor itself, the high performance is poorer, to have a broad smooth speed range, generally USES the dc motor. Nearly one hundred and twenty years, on the basis of the power electronic device and a microcomputer developed ac induction motor speed control system, make the speed regulating performance of asynchronous motor is able to change, and thus its application more widely. Asynchronous motor is running, must absorb reactive power from the grid, which will make the power factor of power grid. Due to the power factor of power grid can use other way to compensate, so this does not prevent the widespread use of asynchronous motor. Main classification 3 asynchronous motor Many different kinds of asynchronous motor, have different classification from different angles. According to the number of stator phase points are single-phase asynchronous motor, three-phase asynchronous motor. According to the rotor winding form, generally can be divided into wound rotor and cage type two kinds. Squirrel-cage asynchronous motor, and a single cage, double squirrel cage and deep www.dongfeng-motor.com slot. According to the size of the motor or power, is divided into large, medium, small size and low power motor. According to the motor protection form into open, protected, enclosed. In addition, you can press the motor run time of ventilation and cooling, installation structure, insulation class, working methods such as classification, here is differ a list.

Seven methods for three-phase asynchronous motor drive

The seven kinds of three-phase asynchronous motor control method and characteristics:Introduces seven kinds of three-phase asynchronous motor speed control mode and its characteristic, pointed out its

applicable occasions and situations. For three-phase asynchronous motor speed formula: n = 60 f/p (1

- s) from the type, change the power supply frequency f, slip ratio of the motor very logarithmic p

and s can be too much to change speed.A,classification:1,from the www.facebook.com/dongfeng.motor perspective of the nature of speed regulation,different way of speed adjustment is nothing but change synchronous ac motor synchronous speed or not turn two. Don't change the synchronous speed control methods are: 1) the wound rotor motor rotor series resistance speed dc chopper, 2), 3) cascade speed regulation and application of the electromagnetic slip clutch, 4) hydraulic coupling, such as 5) oil-film clutch speed regulation. Don't change the synchronous speed of speed regulation method is widely used in the production of machinery.2, the change of the synchronous speed logarithmic multi- speed motor, stator can change of the stator voltage, frequency, frequency control of motor speed has no commutator motor speed regulation and so on.

3, from the energy point of view, when there are 1) high speed control method and (2) low speed regulation method two: an induction refers to the effective speed control is constant, so there is no slip loss, such as multi-speed motor, frequency control of motor speed and slip loss can be recovered speed control methods (such as cascade speed regulation, etc.). Have slip loss speed regulation method belongs to the low speed, such as rotor series resistance speed control method, the energy loss in the rotor circuit; Electromagnetic clutch speed regulation method of energy loss in the clutch coil; Hydraulic coupler speed regulation and energy loss in the oil of hydraulic coupling. In general slip loss increases with expanding range of speed regulation, if the speed range is not big, energy loss is small.A, logarithmic pole change speed regulation method: this method of speed control is in change of the stator winding red way to change the speed cage motor stator polar logarithmic to achieve. This method is suitable for don't

need a stepless speed regulation of production machinery, such as metal cutting machine tools,

elevators, lifting equipment, fan, water pump, etc.Characteristics are as follows: 1, with a hard

mechanical properties, good stability; 2, no rotor cutting machine slip loss, high efficiency; 3, simple

wiring and convenient control, low price; 4, have used differential is bigger, cannot obtain smooth

speed regulation; 5, can be used with regulating speed control, electromagnetic slip clutch, smooth

speed characteristics of high efficiency. Second, the method of frequency control of motor speed:

frequency control of motor speed is to change the frequency of the motor stator power, to change its

synchronous speed control method. 

Variable frequency speed regulation system is the main equipment to provide frequency conversion power of inverter, the inverter can be divided into ac - dc - ac frequency converter and ac - ac frequency converter two kinds big, cross - straight - to pay inverter are mostly used in China at present. This method is suitable for the requirement of high precision, better speed control performance. Its features: 1, high efficiency, speed the process of no additional loss; 2, wide application range, can be used in the cage type asynchronous motor; 3, large range of speed regulation, and the characteristics of hard, high precision; 4, complex technology, high cost, maintenance difficulties. Three, cascade speed regulation method: cascade speed regulation refers to the wound rotor motor rotor loop series adjustable the additional

potential to change the slip of the motor, to achieve the purpose of speed control. Most of the slip

power is absorbed by series of additional potential to recycle produce additional device, the

absorption of returning the slip power grid or conversion of energy use. According to the slip power

utilization way, cascade speed regulation can be divided into motor cascade speed regulation,

mechanical cascade speed regulation and thyristor cascade speed regulation form, adopts thyristor

cascade speed regulation. This method is suitable for the ac synchronous motor fan, water pump and the rolling mill, mine hoist, the extrusion machine use. 

Its characteristic is: 1, but will slip loss in the process of speed feedback to the grid or production machinery, high efficiency; 2, unit capacity is proportional to the speed range, saving investment, apply to speed range in production machinery from 70% to 90% of the rated speed; 3, speed regulating device failure can switch to run at full speed, avoid production; 4, thyristor cascade speed regulation low power factor, harmonic impact is bigger. Four, wound rotor motor rotor series resistance speed control methods: wound rotor asynchronous motor rotor string into the additional resistance, make the slip of the motor, motor under low speed running. The series resistance, the greater the lower the speed of the motor. This method is simple, easy to control, but the slip power consumption in the form of heat on the

resistance. Step speed, mechanical properties of soft. Five, the stator voltage regulating speed

control methods: changes of motor stator voltage, be able to get a different set of mechanical

characteristic curve, in order to gain different speed. Due to the torque of the motor and the

voltage is proportional to square, thus maximum torque decreased a lot, the smaller range of speed

regulation, and makes difficult to apply general squirrel-cage motor. In order to enlarge the speed

range, regulating speed rotor resistance value should be adopted for the big cage motor, such as

torque motor, USES for regulating speed or frequency on the wound rotor motor series resistor. 

In order to expand the stable operation range, speed above 2:1 Settings when feedback control should be

adopted to achieve automatic adjustment speed. Regulating speed control is a main device can provide

voltage change of power supply, the current commonly used ways with saturable reactor in series

voltage regulator, autotransformer and thyristor voltage regulation. Thyristor voltage regulation

mode is the best. Regulating speed generally applicable to the production machinery under 100 kw.

The characteristics of the pressure regulating speed: 1, the pressure regulating speed control

circuit is simple, easy to realize automatic control; 2, in the form of heat transfer differential

pressure regulating process power consumption in the rotor resistance and low efficiency. Six,

electromagnetic speed regulating motor speed adjustment method: by cage motor electromagnetic speed

control motor, electromagnetic slip clutch and dc excitation source (controller) of three parts. Dc

excitation power is small, usually by a single-phase half-wave or full wave thyristor rectifier,

change the thyristor conduction Angle, can change the size of the field current. Electromagnetic slip

clutch armature, poles and excitation windings of three parts. The armature and the latter is no

mechanical contact, can free rotation. Armature and motor rotor coaxial connecting said active part,

by the motor drive; Pole docking with the shaft coupling and load according to secondary part. When

the armature and pole are static, such as passing a dc excitation winding, the surface will form

several along the air gap circle on N, S alternating polarity magnetic pole, the magnetic flux

through the armature. 

When the armature motor rotates with drag, because of the relative movement between the armature and pole, thus make the armature induced eddy current, the eddy current and magnetic flux interact to produce torque, driving a pole rotor according to the same direction, but its speed constant is lower than the speed of the armature N1, this is a way of slip speed, change of slip clutch dc excitation current, you can change the clutch output torque and rotational speed. This method is suitable for medium and small power, the requirement is smooth, short-time running at low speed production machinery. Electromagnetic speed regulating motor speed control features: 1, device structure and the control circuit is simple, reliable operation and convenient maintenance; 2, speed smooth, stepless speed regulation; 3, no harmonic of power grids affected; 4, the speed loss and low efficiency. Seven, and hydraulic coupler speed regulation method: hydraulic coupler is a kind of hydraulic transmission device, generally consists of pump wheel and turbine, working, they referred in the seal housing. Into a certain amount of working fluid in the shell, when the impeller rotates, under the prime in the liquid by the rotating blades to promote, in under the action of centrifugal force along the outer ring into the turbine and pump wheel is on the same shift to the turbine blades to thrust, the mechanical operation of the production. Hydraulic coupler shell power transfer capacity and the relative to the size of the amount of liquid is the same. In the process of work, the change rate of liquid can change coupler turbine speed, achieve stepless speed regulation. This method is suitable for the fan and water pump speed. Its characteristic is: 1, the power to adapt to the scope is big, can meet different power from tens of kilowatts to thousands of kilowatts of needs; 2, simple structure, reliable operation, convenient use and maintenance, and low cost. 3, small size, can let big; 4, convenient control, easy to realize automatic control.