CN1074197C

CN1074197C - Wire-wound variable-pole asynchronous motor with AC-DC converting output rotor

Info

Publication number: CN1074197C
Application number: CN97109052A
Authority: CN
Inventors: 王雪帆
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 1997-03-24
Filing date: 1997-03-24
Publication date: 2001-10-31
Anticipated expiration: 2017-03-24
Also published as: CN1166716A

Abstract

The present invention relates to a wire-winding pole-changing asynchronous motor winding with an AC-DC converting output rotor. The rotor winding has the composition mode that for the pole changing winding of the wire-winding rotor with n pole numbers, one pole number is appointed at will to divide the rotor winding into m phases. Each phase is divided into one section according to the phase of rest pole numbers to form all windings with one m phase symmetrical system. The AC output of each symmetrical system is respectively transformed into the DC for outputting through a rectifier on the rotor. 2 or 3 guiding wires are output by the whole rotor. The present invention has the method that the motor structure can be the same as the single speed motor, and the number o the leading-out wires of the rotor winding is small to make the rotor structure simplified. The present invention does not need a switch for switch.

Description

Rotor adopts the winding-type pole-changing asynchronous motor of friendship-straight unsteady flow output

The invention belongs to rotor and adopt the winding-type pole-changing asynchronous motor winding that friendship-straight unsteady flow is exported.

Prior art often adopts the method for wound rotor asynchronous motor rotor string additional resistance speed governing in the dragging of manufacturing machines such as metallurgy or lifting.This speed regulating method is simple and reliable, but that its shortcoming is an energy consumption is excessive, and underloading to reduce quick-acting fruits not obvious.For addressing this problem, can consider itself and pole changing are combined.

But present The Asynchronous Motor of Speed Adjustment in Polarity mostly is the cage-type rotor motor greatly, and this is that the number of poles of motor only is decided by stator because of its rotor itself does not have definite number of poles, and when stator poles changed, the rotor number of poles can change automatically thereupon; Common winding rotor motor but can not be accomplished this point, and wound rotor has definite number of poles, when changing stator poles, must change the rotor number of poles simultaneously, otherwise motor can not be worked.

The pole-changing of wound rotor generally is to use the way similar with the stator pole-changing, and rotor winding at this moment needs 6 outlets at least and draws through slip ring.But 3 slip rings only are housed generally on the common wound rotor, if 6 outlets all will be drawn, must install 3 slip rings additional, so, not only need to change rotor structure, and understand the frictional dissipation that increase between slip ring and the brush meaninglessly, simultaneously, too much lead-out wire also can make the pole-changing transition apparatus complicated.Therefore, but the wound rotor motor of pole changing also preferably only with three slip rings, what Practical significance too much slip ring does not have.

Only with the wound rotor pole-changing of three slip rings, the way that adopts has two at present: (1) a kind of number of poles lower rotor part winding is from short circuit; (2) the conjugation harmonic wave that utilizes the reverse method pole-changing to produce.These two ways, wherein (1) rotor winding can only seal in outer meeting resistance under a kind of number of poles, and another kind of number of poles is following to being in from short-circuit condition, it is inoperative to regulate guest performer's resistance, so in fact can only accomplish to be the wound rotor performance under a kind of number of poles; (2) though can accomplish all can seal in outer meeting resistance under two kinds of numbers of poles, its fatal shortcoming is that conjugation Harmonic Distribution coefficient is often much smaller than first-harmonic, causes the motor rotor leakage reactance big, and overload capacity is low, thereby can't use.

Rule of thumb, the wound rotor variable-pole winding wants to accomplish all to seal in outer meeting resistance under two kinds of numbers of poles and good performance is arranged, and the lead-out wire more than 6 or 6 still should be arranged, but present problem is, can only allow 3 slip rings on the rotor, all outlets can only be drawn via these 3 slip rings.

The present invention is directed to the problems of the prior art, a kind of method that adopts ac-dc conversion is proposed, with the original lead-out wire more than 6 or 6 of winding-type pole-changing asynchronous motor rotor winding, being transformed to 2 or 3 lead-out wires draws through slip ring again, all can seal in outer meeting resistance under the n kind number of poles and regulate rotating speed to be implemented in, and the winding-type pole-changing asynchronous motor of good runnability can be arranged.

Rotor of the present invention adopts the winding-type pole-changing asynchronous motor of friendship-straight unsteady flow output, the main thought of its ac-dc conversion method is in the wound rotor variable-pole winding, the application bridge rectifier is direct current output with the interchange output transform of original rotor, thereby reach the purpose that reduces rotor winding lead-out wire, its design fundamentals and method can be summarized as follows:

To having the wound rotor variable-pole winding of n kind number of poles, specifying a kind of number of poles to do substantially extremely to divide the rotor winding at first arbitrarily is the m phase, be further divided into 1 section by the phase place of all the other numbers of poles mutually with every respectively then, (above n, m, l is positive integer), and make each section all have high relatively winding coefficient to constitute the symmetrical system of m with all the other corresponding sections mutually to all numbers of poles, promptly at this moment whole windings contain 1 symmetrical system of m altogether, the interchange output of each symmetrical system is transformed to direct current output through being installed in epitrochanterian rectifier respectively, after this 1 dc output end appropriate combination, the whole rotor externally lead-out wire of output is 2 or 3.

Illustrated in figures 1 and 2 is two kinds of possible combinations.Wherein, Figure 1 shows that the forward combination, only need two slip rings; Figure 2 shows that and separate combination, two cover systems are not contact on circuit, needs 3 slip rings, but allows each half-phase that higher voltage is arranged, and this is favourable to reducing the rectifier loss.

Rotor of the present invention adopts the winding-type pole-changing asynchronous motor of friendship-straight unsteady flow output, utilize 3 common phase bridge rectifiers that the ac output end that has 6 lead-out wires in the former rotor loop is handed over-straight conversion process, the winding of result after such simple process with compared originally, but under the constant situation of the character that guarantees crosstalk resistance under the n kind number of poles, the external lead-out wire of rotor is reduced to 2 or 3 by 6, thereby has solved this problem of the prior art.When adopting method pole-changing of the present invention, electric machine structure can be identical with single speed motor, rotor does not need switch yet and carries out changing-over, but it should be noted that, become direct current output owing to exchange output now, at this moment outer meeting resistance is preferably selected iron or copper alloy resistance for use, and does not use quick resistance frequently.

Fig. 1: the friendship of forward tandem compound-straight unsteady flow output winding-type pole-changing asynchronous motor rotor winding;

Fig. 2: the friendship-straight unsteady flow output winding-type pole-changing asynchronous motor rotor winding that separates combination.

Fig. 3: 8 utmost point slot-number phase graphs

Fig. 4: 16 utmost point slot-number phase graphs

Fig. 5: 16 utmost points, 3 phase distribution maps

Fig. 6: 8/16 utmost point, 48 grooves are handed over-straight conversion rotor winding coupling figure

Fig. 7: 8 utmost point M-n characteristic curves

Fig. 8: 16 utmost point M-n characteristic curves

In order to be illustrated more clearly in design of the present invention and structural principle, with two kinds of numbers of poles commonly used, three phase electric machine is that example is further described.

To given ultimate ratio p ₁/ p ₂(n=2) wound rotor variable-pole winding conceptual design: specify a kind of number of poles, for example p at first arbitrarily ₁, doing substantially extremely to divide the rotor winding is three-phase (m=3), adopts reverse method pole-changing technology by p then ₂Phase place with every two half-phases (l=2) that are further divided into mutually, these two half-phases are to p ₁, phase place is identical, to p ₂, phase place is then opposite, and three-phase has 6 half-phases, and it all is symmetrical having constituted respectively under two kinds of numbers of poles, respectively contains two three-phase system A1, B1, the C1 of three half-phases; A2, B2, C2, have 6 lead-out wires, the interchange of these two three-phase systems output is installed in epitrochanterian three-phase bridge rectifier DZ through two respectively is transformed to direct current output, to after these two dc terminal appropriate combination (as shown in Figure 1 and Figure 2), the whole rotor externally lead-out wire of output is 2 or 3 again.

Below with n=2, m=3, l=2,8/16 utmost point, 48 groove wound rotor windings are example, and above-mentioned wound rotor ac-dc conversion 3 slip rings output variable-pole winding conceptual design is specifically described.

At first make 48 grooves, 8 utmost point slot-number phase graphs are also pressed row 6 five equilibriums with it, and every five equilibrium phase bandwidth is 60 °, is labeled as A1 respectively, C2, and B1, A2, C1, B2 promptly is respectively aforementioned 6 half-phase windings (m=3, l=2), as shown in Figure 3, and A1 wherein, B1, C1, and A2, B2, C2.

Remake 48 grooves then, 16 utmost point slot-number phase graphs, as shown in Figure 4.With the groove of above-mentioned 6 half-phase windings number, also be A1, B1, C1, and A2, B2, these two parts of C2 are drawn again by 16 utmost point phase places, as shown in Figure 5.As can be seen, two parts still constitute two symmetrical three-phase alternating current systems respectively.Different is, for 8 utmost points, every phase phase bandwidth is 60 °, and two part phase places are just in time opposite; For 16 utmost points, every phase phase bandwidth is 120 °, and two part phase places are identical.

Winding wire ring recess number concrete the connection as shown in Figure 6.As can be seen, for interchange, if only allow 3 lead-out wires, these two three-phase systems do not have how to connect combination so, and perhaps 8 utmost points or 16 utmost points always have the most of electric current of phase place official post that existence is bigger under a kind of number of poles and do not pass through outer meeting resistance, and through behind the friendship-DC converter, two 3 cross streams systems are separated from each other, and under the situation that allows 3 lead-out wires, then can guarantee no matter be that 8 utmost points or 16 electrode currents must could constitute the loop by outer meeting resistance equally.

Scheme shown in Figure 6 changes around experiment for carried out winding on a YZR180L support wound rotor motor, and wherein stator employing connection is the 2Y/ Δ.During respectively with rotor short-circuit and string one-level outer meeting resistance measured M-n (torque-speed) characteristic curve as shown in Figure 7 and Figure 8, fine line is represented rotor short-circuit among the figure, heavy line represents that rotor seals in resistance, abscissa is free calibration, only has relative meaning.As can be seen, the characteristic curve under two kinds of numbers of poles all has highly significant to change, and this illustrative experiment motor properties reaches the expection requirement fully.

Claims

1. a rotor adopts the winding-type pole-changing asynchronous motor that friendship-straight unsteady flow is exported, the rotor winding is the variable-pole winding with two kinds of numbers of poles, its constituted mode is, specify a kind of number of poles to do substantially extremely to divide the three-phase that the rotor winding is 120 ° of symmetries of mutual deviation at first arbitrarily, the phase place by another kind of number of poles is further divided into 1 section mutually with every then; When 1=2, these two sections for a kind of number of poles, and phase place is identical; And for another kind of number of poles, phase place is opposite, 1 when getting other numerical value, also should make each section that two kinds of numbers of poles are all had high relatively winding coefficient, each section constitutes the three-phase symmetrical system by three symmetrical principles with all the other two corresponding sections with this then, promptly at this moment whole windings contain 1 symmetrical system altogether, the interchange output of each symmetrical system is transformed to direct current output through being installed in epitrochanterian rectifier respectively, after this 1 dc output end appropriate combination, the whole rotor externally lead-out wire of output is 2 or 3.

2. according to the winding-type pole-changing asynchronous motor of the said friendship of claim 1-straight unsteady flow output, the interchange output of its rotor can be connected with a resistance by two slip rings after being installed in epitrochanterian rectifier DZ and being transformed to direct current output.

3. according to the winding-type pole-changing asynchronous motor of the said friendship of claim 1-straight unsteady flow output, the interchange output of its rotor can be connected with two resistance by 3 slip rings after being installed in epitrochanterian rectifier DZ and being transformed to direct current output.