CN2128799Y - Parameter voltage change induction motor and its controlling apparatus - Google Patents
Parameter voltage change induction motor and its controlling apparatus Download PDFInfo
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- CN2128799Y CN2128799Y CN92214653U CN92214653U CN2128799Y CN 2128799 Y CN2128799 Y CN 2128799Y CN 92214653 U CN92214653 U CN 92214653U CN 92214653 U CN92214653 U CN 92214653U CN 2128799 Y CN2128799 Y CN 2128799Y
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Abstract
The utility model relates to a parameter voltage change induction motor and a control apparatus thereof. Each phase stator winding of the motor running in star-shaped connection are wound by two equivalent insulated wires with identical materials and equal cross section areas in parallel. Twelve terminals of three phases are connected with a wire outlet box. According to the value of a motor load rate, the utility model controls the motor windings by a control circuit and a main circuit, and realizes the parameter voltage transformation of the motor in order to achieve different running effect. When the motor load rate is less than 75%, the utility model can reduce motor current, and improves the efficiency and the power factor of the motor. The utility model is used for the electric drive systems of industry, agriculture, national defense, etc.
Description
The utility model belongs to induction motor and control device thereof
According to investigations, the induction asynchtonous motor of actual motion, most of actual loading is in light running for a long time far below its nominal load, and this is directed at decrease in efficiency, and power factor reduces.Induction motor is that 4～7 times of rated current degenerate grid voltage quality owing to there being starting current, produces a series of harmful effects.For many years, people are devoted for years in addressing the above problem.
Show according to the retrieval: " multifunctional motor " that Patent Office of the People's Republic of China accepts (application number 88105802.5) is each phase winding of stator to be divided into two cover windings embed, and a cover connects winding for Δ, and a cover Y connects winding, and two cover windings are 30 ° of electrical degrees of mutual deviation each other.Leading-out terminal has nine statures, so that change connection and operation, but has two problems: the one, " coiling and wiring are complicated ", the terminated line copper consumption is more; The 2nd, under the operation of Δ connection and two kinds of situations of Y-Δ connection operation, the current density that can only satisfy in a kind of situation lead equates that when the current density in running on lead was unequal, two cover heating in windings were inhomogeneous, might burn motor.
" automatic switching three-power motor " (application number 89103774.8) of being accepted by Patent Office of the People's Republic of China is to have two branch road parallel connections, double-deck repeatedly around two cover stator winding, the tail end of every phase first cover stator winding and the head end of the second cover stator winding link, the connection place is extracted a tap out, three-phase has nine leading-out terminals, is connected into the delta connection operation when heavy duty, when medium load, be connected into the Y connection operation of a part of number of turn, when underloading, be connected into the Y connection operation of the full number of turn.But also there are two shortcomings: the one, be not suitable for windings such as individual layer and mixing, if and by the turn ratio 11:5 of this patent working example, be not suitable for three and three multiple to utmost point motor, because the empty turn ratio that does not connect is 5/ (11+5) ≈ 1/3 when being connected into the mid power operation, for a phase winding, a certain conductor under extremely almost is that empty work need not entirely, mechanical oscillation will take place in operation in this case, and noise increases, shorten motor useful life, and material is used insufficient; The 2nd, manufacturing process is complicated.
The purpose of this utility model is a kind of induction motor of development, has both solved the problem of induction motor " low load with strong power ", starting current is reduced, and remedied the deficiency of above-mentioned two inventions.
To achieve these goals, the utility model adopts following technical proposal:
Existing specified operation be the Δ connection design of electrical motor, be fabricated to the motor that specified operation is the Y connection, employed material is equal fully.The motor of Y connection operation is comprised it being that every phase stator winding of motor of Y connection operation equates with the cross-sectional area of equivalence now, and material identical two thoroughly do away with the edge leads and around.Every phase and around four statures of two leads be connected to outlet box, like this, three-phase just has 12 statures to be connected to outlet box, wherein 1U1,2U1,1V1,2V1,1W1,2W1 six statures are head end, 1U2,2U2,1V2,2V2,1W2,2W2 six statures are tail end.When operation, according to the height of load-rate of motor, by changing parameter and the voltage that connection changes phase winding, to reach different operational effects.When actual loading rate during in 70～100% scopes, the tail end of three-phase six conductors is unified into a bit and becomes the asterism of Y operation, each mutually the head of two leads respectively connect the head that becomes each phase for a bit, like this, three-phase just constitutes double joint Y operation.When actual loading rate during,, be connected into the triangle operation again the tail of each phase, after first the connection in 30～70% scopes.When actual loading rate during in 20～30% scopes, can be mutually behind two wire tail, the prime ministers' connection with each, again the tail end of a phase is connected to the mid point of another phase and constitutes the extend-triangle operation.When actual loading rate during, can be connected into single Y connection operation again behind each phase tail, the prime minister's connection less than 20% scope.In when starting, according to different load characteristics, take different connection startings, treat that electric motor starting finishes after, switch to needed connection operation again.When the empty load of motor starting, and the pull-in torque of dragging system was connected into single Y connection starting less than 0.5 o'clock with motor.When the motor light start, and the pull-in torque of dragging system was connected into the extend-triangle starting less than 0.7 o'clock with motor.When the motor heavy-load start, and the pull-in torque of dragging system can be connected into motor the delta connection starting greater than 1 o'clock.When distribution network allows across-the-line starting, motor is connected into the across-the-line starting of double joint Y connection.The control of this electric motor starting, operation is all adopted formation control device such as contactor, relay, has been realized the conversion of above-mentioned single Y, extend-triangle, triangle, double joint Y connection.
In order to realize the various conversions of above-mentioned various starting, operation connection, main order control is adopted in control of the present utility model.Motor---control device dragging system main circuit connection principle such as Fig. 7, control device control circuit connection principle such as Fig. 8.
In main circuit: three-phase contactor K
1The upper end link with motor stator winding 1U2,1V2,1W2 end respectively, lower end and motor stator winding 2U1,2V1,2W1 hold and link, and work as K
1When closed, 1U2,2U1 can join for a bit, and 1V2,2V1 can join for a bit, and 1W2,2W1 can join for a bit.Two phase contact K
2The lower end short circuit after link with the 2V2 of motor stator winding end, the upper end links with motor stator winding 2U2,2W2 respectively.Three-phase contactor K
3The upper end link with motor stator winding 2U1,2V1,2W1 end respectively, the lower end links with motor stator winding 2W2,2U2,2V2 end respectively, works as K
3When closed, 2U1,2W2 connection is for a bit, and 2V1,2U2 connection is for a bit, and 2W1,2V2 join for a bit.Three-phase contactor K
4The upper end link with motor stator winding 1U1,1V1,1W1 end respectively, the lower end links with motor stator winding 2W2,2U2,2V2 end respectively, works as K
4When closed, 1U1,2W2 connection is for a bit, and 1V1,2U2 connection is for a bit, and 1W1,2V2 join for a bit.Three-phase contactor K
5The upper end link with motor stator winding 1U1,1V1,1W1 respectively, the lower end links with motor stator winding 2U1,2V1,2W1 respectively, works as K
5When closed, 1U1,2U1 connection is for a bit, and 1V1,2V1 connection is for a bit, and 1W1,2W1 join for a bit.Two phase contact K
6The lower end short circuit after link with motor stator winding 1V2 end, the upper end links with 1U2,1W2 respectively.
In control circuit: the first, by following four branch road parallel connections: article one branch road is button S
1Normally open contact, contactor K
2, K
5often open after the auxiliary contact parallel connection and button S
2, S
3Normally closed interlock, contactor K
3, K
4Normally closed auxiliary contact, contactor K
2Coil series connection; The second branch road is contactor K
2, K
3, K
4often open after the auxiliary contact parallel connection and contactor K
5Normally closed auxiliary contact, contactor K
1Coil series connection; Article three, branch road is contactor K
3often open auxiliary contact and button S
4Normally closed interlock series connection back and button S
2The normally open contact parallel connection, this parallel circuits again with contactor K
2, K
4Normally closed auxiliary contact, contactor K
3Coil series connection; Article four, branch road is button S
4, S
3Normally open contact, contactor K
4often open the auxiliary contact parallel connection after, with contactor K
2, K
3Normally closed auxiliary contact, contactor K
4Coil series connection.After these four circuit branch parallel connections with button S
5Normally closed interlock series connection and constitute article one electricity loop.The second, by button S
5Normally open contact and contactor K
6often open after the auxiliary contact parallel connection and contactor K
1The series connection of normally closed auxiliary contact, and then with contactor K
5, K
6The circuit series connection of coils from parallel connection of coils, constitute second electricity loop.The 3rd, by connecting with button S again after first, second electric loop parallel connection.
Any two ends that two of this control circuit is connected to asynchronous motor U, V, W three phase mains gets final product.
The operating principle of control system is in Fig. 7, Fig. 8.
When the motor no-load starting, press single Y starting button S
1, K
2Coil electricity, K
2The normally open contact closure, normally closed interlock disconnects, K
1Coil electricity, K
1The normally open contact closure, normally closed interlock disconnects, the single Y starting of motor.After treating that electric motor starting finishes, if press S
2Button, K
2Coil blackout, K
2Each contact resets, K
3Coil electricity, K
3The normally open contact closure, normally closed auxiliary contact disconnects, the operation of motor extend-triangle; If press the button S
3, K then
2Coil blackout, K
2Each contact resets, K
4Coil electricity, K
4The normally open contact closure, normally closed interlock disconnects, the operation of motor triangle; If press the button S
5, K then
2, K
1Coil blackout, K
2, K
1Each contact resets, K
5, K
6Coil electricity, K
5, K
6The normally open contact closure, normally closed interlock disconnects, and is directed at K
2Coil is switched on again, K
2The normally open contact closure, normally closed interlock disconnects, motor double joint Y connection heavy service.
When the motor light start, press extend-triangle starting button S
2, K
3Coil electricity, K
3The normally open contact closure, normally closed interlock disconnects, K
1Coil electricity, K
1The normal switching closed, normally closed disconnection, the starting of motor extend-triangle.At this moment, if press S
4, K then
4Coil electricity, K
4The normally open contact closure, normally closed interlock disconnects, and motor is connected into the triangle light running; If press S
5, motor double joint Y connection heavy service then.
When the motor heavy-load start, press the button S
4, the starting of motor triangle.After treating that electric motor starting finishes, if light running, then not according to other any button; If heavy service then presses the button S
5, motor switches to double joint Y connection heavy service.
When distribution network allows across-the-line starting, then press S
5, motor is then delivered directly the electrical network starting.
Press the button S and get final product when stopping motor.
The effect of this utility model, this motor have identical runnability with the Y series motor that China Ministry of Energy present large-scale popularization is used when running on heavy duty.In running on, carry or during underloading the user can regulate operational effect easily, its electric current is reduced, efficient and power factor raise, and The theoretical analysis and actual measurement show, when the actual loading rate of motor is 50%, line current can reduce more than 13%, it is about 2% that efficient improves, and power factor improves more than 10%, aspect starting, when connecing to single Y starting, starting current is 1/4 of direct-on-line starting; When connecing when starting for extend-triangle, starting current is 3/8 of direct-on-line starting; When connecing when starting for triangle, starting current is 3/4 of direct-on-line starting.The kinetic energy that rises of this motor replaces the auto-induction voltage-reduced starting device fully.
This utility model is widely used in all systems that needs Electric Traction such as industry, agricultural, national defence.
Fig. 1 is the utility model motor windings expanded view, only draws the U phase among the figure, and for clear, V, W omit mutually.
Fig. 2 is the Pareto diagram of the utility model motor windings leading-out terminal on terminal box internal wiring plate
Fig. 3 is that the utility model motor windings double joint Y connects winding diagram
Fig. 4 is that the utility model motor windings triangle connects winding diagram
Fig. 5 is that the utility model motor windings extend-triangle connects winding diagram
Fig. 6 is that the single Y of the utility model motor windings connects winding diagram
Fig. 7 is the utility model motor---control device system major loop elementary diagram
Fig. 8 is the utility model control device control loop elementary diagram
Fig. 9 is electric current, efficient, the power factor curve of two kinds of connection operations of the utility model motor embodiment.
The utility model is described in further detail below in conjunction with accompanying drawing.
4 kilowatts of The parameter voltage variation induction asynchtonous motor of having developed is one, 4 utmost point interconnected cage motors, stator winding with the high strength enamelled wire of two φ=1.00 millimeter and around, every groove conductor several 26, developed winding diagram such as Fig. 1 for clarity, have only drawn the U phase among the figure, after all the other V, 120 ° of of of of electrical of W differed degrees interdependent time, winding method was mutually just the same with the U that draws.Among Fig. 1, solid line is represented first lead, and dotted line is represented second lead.Represent three phase windings with U, V, W, as Fig. 2, first lead of " 1 " on alphabetical left side expression, second lead of " 2 " expression; The head end of " 1 " expression lead on letter the right, the tail end of " 2 " expression lead.Three-phase 12 statures on terminal block put in order for:going up horizontally-arranged is 1U2,2U2,1V2,2V2,1W2,2W2, and following horizontally-arranged is 1U1,2U1,1V1,2V1,1W1,2W1, as Fig. 2.If motor actual loading rate is when 70～100% scopes, motor can be connect operation into double joint Y, be about to 1U2,2U2,1V2,2V2,1W2,2W2 connection among Fig. 2 for a bit, it is asterism, 1U1,2U1 connection becomes the U phase for a bit, and 1V1,2V1 connection becomes the V phase for a bit, 1W1,2W1 connection becomes the W phase for a bit, as Fig. 3.If motor actual loading rate is when the 30-70% scope, after two wire tail, prime ministers of each phase are connect, be connected into the delta connection operation again, be about to 1U2,2U1 connection among Fig. 2 for a bit, 1V2,2V1 connection is for a bit, 1W2,2W1 connection is for a bit, and becomes U, V, W phase, U, V, W is linked into triangle to move again, be that 1U1,2W2 connection is for being connected to the U phase of power supply after a bit, be connected to the V phase of power supply after 1V1,2U2 are unified into a bit, be connected to the W phase of power supply after 1W1,2V2 are unified into a bit, as Fig. 4.When motor was connected into the delta connection operation, because variation has taken place the parameter voltage of motor, by theory analysis as can be known, iron loss reduced, and efficient and power factor improve, and electric current reduces, and does not have Harmonic Interference.If motor actual loading rate is when 20～30% scopes, two wire tail, prime ministers of each phase can be joined constitute one mutually after, again the tail end of a phase is connected to the mid point of another phase and constitutes the extend-triangle operation.Be about to 1U2,2U1,2W2 connection among Fig. 2 for a bit, 1V2,2V1,2U2 connection be for a bit, and 1W2,2W1,2V2 join for a bit, and 1U1,1V1,1W1 connect the three-phase of power supply respectively, as Fig. 5.If motor actual loading rate is less than 20%, can be behind two wire tail of each phase of motor, the prime minister's connection, be unified into single Y connection operation again, be about to 1U2,2U1 connection among Fig. 2 for a bit, 1V2,2V1 connection is for a bit, and 1W2,2W1 connection becomes U, V, W phase for a bit, 2U2,2V2,2W2 is joined for any becomes asterism again, be connected to three phase mains by 1U1,1V1,1W1, as Fig. 6.
Starting.During empty load of motor starting (dragging the DC generator of no excitation as induction motor), the single Y connection that motor is connected into Fig. 6 is started, and behind the proceed-to-send, switches to needed connection operation again.Because the impedance of single Y connection is 4 times of impedance of double joint Y connection, so single Y connection starting current is 1/4 of a double joint Y connection starting current, 1/4 of double joint Y connection is also reduced in torque.During light start, the extend-triangle that motor is connected into Fig. 5 starts, and behind the proceed-to-send, switches to needed connection operation again.Because the impedance of extend-triangle connection is 8/3 of double joint Y connection impedance, so the starting current extend-triangle is 3/8 of double joint Y, its starting torque is also reduced to 3/8 of double joint Y.During the nominal torque starting, the delta connection that motor is connected into Fig. 4 is started, and behind the proceed-to-send, switches to needed connection operation.Because the impedance of delta connection is 4/3 of double joint Y connection impedance, its starting current is 3/4 of double joint Y, and 3/4 of double joint Y is also reduced in torque.Direct-on-line starting is connected into Fig. 3 double joint Y starting to motor.
To the 4KW three-phase squirrel-cage induction motor of having developed.Because the load factor scope that double joint Y connection and delta connection motor move is the wideest, move the most generally, the operation characteristic that these two kinds of connections are moved under rated voltage is tested.Test gained system effectiveness η=f(β), powerfactorcos
1=f(β), stator current relative value I
1*=and f(β) curve retouches in Fig. 9.During test, induction asynchtonous motor drags a DC generator, system effectiveness be the DC generator power output than asynchronous motor input power, so be called system effectiveness, β is the induction motor load factor.Among Fig. 9: the efficiency curve when 1. curve is the operation of double joint Y connection.2. curve be ▲ efficiency curve during the connection operation, more 1., 2. two curves, when load factor less than 70% the time, efficient when the efficient the during operation of ▲ connection is higher than the operation of double joint Y connection, load factor during double joint Y is low more, change into ▲ connection operation after, its efficient improves many more, when load factor was 50%, system effectiveness can improve about 2%.Power factor curve when 3. curve is the operation of double joint Y connection, 4. curve be ▲ power factor curve during the connection operation, and more 3., 4. two curves, the power factor curve of ▲ power factor curve when moving during than double joint Y connection is much higher, when load factor is 50%, can be up to 14%.Stator line current curve when 5. curve is the operation of double joint Y connection, 6. curve be ▲ stator line current curve during the connection operation, more 5., 6. two curves, stator line current curve when the stator line current curve ratio double joint Y connection of ▲ connection operation is moved is low, load factor is low more, curve is 6. manyly more 5. low than curve, and when load factor was 50%, 5. 6. curve hanged down about 14% than curve.Comprehensive above several main and important performance index, the parameter voltage variation induction asynchtonous motor, when heavy duty, the y series motor of using with China Ministry of Energy large-scale popularization has identical runnability, during underloading, carry out the parameter voltage variation operation,, all be better than the Y series motor of same model for three indexs that have been listed as.
Claims (1)
1, a kind of parameter voltage variation induction motor and control device thereof, comprise motor stator, rotor, support, end cap, outlet box, be connected to the main circuit of outlet box and three phase mains and be connected in the induction motor three phase mains control circuit of two-phase arbitrarily, it is characterized in that:
(1) specified operation be delta connection design of electrical motor, be fabricated to the motor that specified operation is a star connection, every phase stator winding of the motor of star connection operation with equivalence, that cross-sectional area equates and material is identical two thoroughly do away with the edge leads and around, every phase and around two four statures that thoroughly do away with the edge leads be connected to outlet box, U, V, W three-phase have 12 statures to be connected to outlet box, wherein six stature 1U1,2U1,1V1,2V1,1W1,2W1 are head end, and other six stature 1U2,2U2,1V2,2V2,1W2,2W2 are tail end;
(2) the three-phase contactor K in the main circuit
1The upper end link with the tail end of first lead of motor threephase stator winding respectively, the head end of second lead of its lower end and threephase stator winding links, two phase contact K
2The lower end short circuit after link with the tail end of V second lead mutually of motor stator winding, its upper end connects three-phase contactor K with the tail end of motor stator winding U, W second lead mutually respectively
3The upper end link with the head end of second lead of motor threephase stator winding respectively, its lower end connects three-phase contactor K with the tail end of second lead of motor threephase stator winding respectively
4The upper end link with the head end of first lead of motor threephase stator winding respectively, its lower end connects three-phase contactor K with the tail end of second lead of motor threephase stator winding respectively
5The upper end be connected with the head end of first lead of motor threephase stator winding respectively, the lower end links two phase contact K with the head end of second lead of motor threephase stator winding respectively
6The lower end short circuit after, connect with motor stator winding V first lead tail end mutually, its upper end connects with the tail end of motor stator winding U, W first lead mutually respectively;
(3) its control circuit by article one electricity loop be composed in series with button S again after second electricity loop is in parallel, the electric loop of article one by four circuit branch parallel connections after with button S
5Normally closed interlock series connection constitute, four circuit branch situations in parallel are: article one branch road is button S
1Normally open contact, contactor K
2, K
5often open after the auxiliary contact parallel connection and button S
2, S
3Normally closed auxiliary contact, contactor K
3, K
4Normally closed auxiliary contact, contactor K
2Coil series connection, the second branch road is contactor K
2, K
3, K
4often open after the auxiliary contact parallel connection and contactor K
5Normally closed auxiliary contact, contactor K
1Coil series connection, the 3rd branch road is contactor K
2often open auxiliary contact and button S
4Normally closed interlock series connection back and button S
2The normally open contact parallel connection, again with contactor K
2, K
4Normally closed auxiliary contact, contactor K
3Coil series connection, the 4th branch road is button S
4, S
3Normally open contact, contactor K
4often open the auxiliary contact parallel connection after, with contactor K
2, K
3Normally closed auxiliary contact, contactor K
4Coil series connection, second electricity loop is by button S
5Normally open contact and contactor K
6often open after the auxiliary contact parallel connection and contactor K
1The series connection of normally closed auxiliary contact, and then with contactor K
5, K
6Coils from parallel connection of coils after circuit series connection constitute.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN92214653U CN2128799Y (en) | 1992-05-17 | 1992-05-17 | Parameter voltage change induction motor and its controlling apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN92214653U CN2128799Y (en) | 1992-05-17 | 1992-05-17 | Parameter voltage change induction motor and its controlling apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2128799Y true CN2128799Y (en) | 1993-03-24 |
Family
ID=33763801
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN92214653U Expired - Lifetime CN2128799Y (en) | 1992-05-17 | 1992-05-17 | Parameter voltage change induction motor and its controlling apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2128799Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100340058C (en) * | 2005-04-01 | 2007-09-26 | 上海匣承机电科技有限公司 | Three-phase AC. electric motorelectricity-saver |
| CN113037143A (en) * | 2021-04-23 | 2021-06-25 | 大庆恒特电机有限公司 | Flexible dragging method of oil pumping unit |
-
1992
- 1992-05-17 CN CN92214653U patent/CN2128799Y/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100340058C (en) * | 2005-04-01 | 2007-09-26 | 上海匣承机电科技有限公司 | Three-phase AC. electric motorelectricity-saver |
| CN113037143A (en) * | 2021-04-23 | 2021-06-25 | 大庆恒特电机有限公司 | Flexible dragging method of oil pumping unit |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CX01 | Expiry of patent term |