JPS61227700A - Parallel running pole change motor - Google Patents

Abstract

PURPOSE:To enable general balanced parallel operation to be performed through the same bus bars with switches used at minimum, by setting the induced voltage of the idle windings of a plurality of motor units to be the same values. CONSTITUTION:Through bus bars A, the pole change motors M1, M2 of two-step speed are driven via a main switch SW1 for low speed operation and a main switch SW2 for high speed operation. The motors M1, M2 contain the same rated double windings, and by winding up armature core grooves with low speed windings and high speed windings at the same winding positions, the potential difference in a closing circuit constituted with idle windings is set to be zero. Accordingly, circulating current is not induced into the same closing circuit, and so the same phase terminals of each motor unit can be connected together in all. As the result, just with two switches SW1, SW2 used, general balanced parallel operation can be performed through the same bus bars.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a motor device for operating a plurality of two-speed pole-change motors having dual windings in parallel on the same bus bar.

[Technical background of the invention and its problems]

If pole change motors are classified according to the machine winding method,
One type obtains two speeds with a single winding, and the other uses multiple windings to obtain the desired multiple speeds.

There are some that combine the two to obtain multiple speeds.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A conventional example in which a plurality of two-speed pole-change electric motors having double windings among multiple windings are operated at the same time on the same bus bar will be described with reference to the drawings.

FIG. 4 is a system connection diagram for parallel operation (in the case of two motors) of two-speed pole-change motors with built-in double windings. Person is the common bus, SWl is the low-speed side main switch, SW is the high-speed side main switch, Ml is the Nll motor, M2 is the floor 2 motor U, V,
w is the terminal symbol of each phase of the motor, and the first letter of the subscript of the same symbol indicates the motor part, and the second letter is 1, which indicates the low-speed winding, and 2, which indicates the high-speed winding. Therefore, for example tJ
tt indicates the U phase at the low speed winding of the affected motor 1, and U□ indicates Up at the low speed winding of the 2 motor. sw,,sw4 is m
lE! The switch on the low speed side and the switch on the high speed side of the motive
sw, , 8W, is m2'! The low-speed side switch and high-speed side switch of the It motor are shown, respectively. As can be inferred from Figure 4, even though motors with the same rating were operated all at once, six switches were required even if there were two motors. Furthermore, if there were three or four electric motors, eight or ten switches would be required, respectively. For this reason, switching control of the switch related to operation has been extremely complicated.

Furthermore, the control device itself is extremely complex, resulting in high wiring and device costs, and has various other drawbacks.

The main reason for this is the existence of an electrical unbalance factor between the operating motors. Next, the unbalance factor will be explained with reference to Drawing C2.

Figure 5 is column 11! The winding arrangement of a low-speed winding (12-pole winding in this example) and a high-speed winding (4-pole winding in this example) that are wound in the armature core groove of motive M1 is shown. 1 to 36 are armature core groove numbers, ○, Δ1 port indicates U, V, W phase high-speed winding, O-marked U phase is J + "t * " S *
"4-Δ marked V phase is Yl t vt + 'S t '4
! The 10-mark W phase consists of towns 9w19w39w4. Same, U
Phase “1 y ” * s ” l t ” 4 is the other side coil of each coil of “b ” 2 * ” l * ” 4 of the above U phase, and if the so-called U-work ~ u4 is the upper coil, u '1
~u/ means the lower coil.

Although the lower coils of the other V and W phases are not shown, they are regularly arranged like the U phase. ◎, Δ3 mouth is U.

The low-speed windings of the V and W phases are shown, and the U phase marked with ◎ is shown with the coil ~u0. The other V-phase, W-phase, and lower coils are not shown for the sake of explanation. N, 8 indicates a 12-pole magnetic pole arrangement.

In the electric motor M1 with the winding arrangement described above, the low-speed side main switch SW is closed and the low-speed side switch S of the Nll motor is connected as shown in the wiring diagram of Fig. 4.
When W is closed, the bus voltage is applied to the low speed winding and the motor M1 is operated at low speed. on the other hand.

The high-speed winding, which exists as an idle winding, has no bus voltage applied to it, but is excited by the 12 rotating magnetic poles generated by the low-speed winding. Now let's find the induced voltage due to this excitation in the U-phase winding.

Since it is 12-pole excitation, the electrical angle θ of the groove spacing is θ = number of poles x
18 grooves/number of grooves = 12 x tao /36 = eσ, and the induced voltage e in the valley-groove coil of the high-speed winding is e =
008 (calculated by iσ (Mizoki -1). (Only the cosine component is considered) Therefore, the induced voltage e, 11 of the u1 coil group of the high-speed winding is e, l"lX111QQ° (1-1)-1 -IXX16
0" (2-1) + lXl 6σ (3-t) Similarly, the induced voltage et12 of the h coil group is e, x = oos 60'
(10-1)+" 60m (11-1)+CK116
(f (12-1) Similarly, u* # "Induced voltage of 4 coil groups" a3 m '@4 is @,,=n6σ(i9-1
)−)−00160”(20−1)+lX186σ(2
1-1)! , 4 = m6o''(28-1)-)-OQ8
6σ(29-1)+00160'(30-1) Also, the lower coil group of high-speed winding "1 + "t t u'! e
The induced voltage of u'4 is e nl = cog5Q@(6-1) information60'(7-1
)-1-cQtl(5σ(8-1')e a'2 :=
, 1j+ 61)'(15-1)+"60" (16-
1)+"60"Q7-1)e,3'=(1011
60' (24-1) + co86 (f (25-1) inert60" G!6-1 ) eN4' = lx1! + 6σ (3
3-1)-1-00860" (34-1)++XI6σ
(35-1).

FIG. 6 shows the connections of the U-phase coil groups of the high-speed winding.

In this connection, by applying each of the above-mentioned induced voltages, the sum of the U-phase induced voltages EI! ! , find 1.

j! ' B u = (eut -6,1) + (e,;
-6,2')+(e,z-6,: )+(e knee 6u
4'). Specifically, by substituting and rearranging the formula obtained above, we get JP! , = 4 (lXIB120° - tooth 30σ), i.e.
U-phase terminal U3 shown in FIGS. 6 and 7. An induced voltage ΣE is generated between and the neutral point X.

Although only the U-phase has been described above, the other V-phase and W-phase can be obtained in the same way, and their values are the same vector quantity.

C: The induced voltage in the high-speed winding during low-speed operation is as follows:
This is a case where winding of the U-phase first coils of the high-speed winding and the low-speed winding is started from the same groove as the armature core groove level 1. Now, if there is a motor in which the winding of the first coil of the high-speed winding and the slow-speed winding is not started from the same groove, but with a 1% difference between the windings, the winding of the high-speed winding and the slow-speed winding will differ by 1%. The induced voltage is different from the above. This means that the 12 magnetic poles are shifted by one groove, and the induced voltages of all the coils differ by θ = 60''.As a result, when calculating the sum of the induced voltages of the U phase, zB,' = 4 (cossCr-(X)824
0°). In the case of Kono, only the U phase was obtained, but
The other V-phase and W-phase are found in the same way, and their values are the same vector quantities.

This situation I: Even if the motors are of the same rating, motors with different low-speed and high-speed winding arrangements have different induced voltages in their idle windings. Just connect it and drive.

Induced voltage difference C determined above: A current is caused to flow in a closed circuit of the winding terminals, and a so-called circulating current is generated.

This circulating current not only unnecessarily heats up the high-speed winding, which is an idle winding, but also induces extra current in the low-speed winding to counteract the ampere-turns caused by this circulating current, resulting in losses. Increased heating of the first winding or unbalance of the -order current. As a result, maintenance of the system becomes difficult due to burnout of windings and lack of protection coordination for one circuit.

[Purpose of the invention]

An object of the present invention is to provide a two-speed pole-change electric motor device with a built-in double winding that allows multiple motors to be operated in parallel on the same bus bar with the minimum number of switches.

[Summary of the invention]

In order to obtain balanced parallel operation of two-speed pole-changing motors with double windings of the same rating on the same bus and with a minimum number of switches, the low-speed and high-speed windings of all motors are The wires are wound in the armature core groove in the same manner. That is, the positional relationship between the winding start groove of the U-phase low-speed winding and the winding start groove of the U-phase high-speed winding is the same as that of the three-phase winding. As a result, the magnitude of the induced voltage in the idle windings of all motors is made the same, the potential difference in the idle windings forming a closed/open circuit is zero, and no circulating current is caused to flow in the circuit.

[Embodiments of the invention]

Embodiment 1 FIG. 1 is a system connection diagram in the case where a two-speed pole-change motor with built-in double windings is operated in parallel and balanced on the same bus bar according to a first embodiment of the present invention.

1 indicates the busbar, M1 and M2 indicate a two-speed pole change motor with built-in double windings, SW indicates the main switch for low-speed operation, and SW indicates the main switch for high-speed operation.

The terminals of each phase of the low-speed winding of the motor Ml are Ull wvll.
*Wo, each phase terminal of high speed winding is UlRwvll *
``The terminals of each phase of the low-speed winding of H1 heavy electric machine M2 are U□ev*
1 sW! 1. The terminals of each phase of the high-speed winding are U-, V,...
W,, (2 shows.

Here, the winding positional relationship of the low-speed and high-speed windings of the motors M1 and M2 in the armature core groove is completely the same, an example of which is shown in FIG.

FIG. 2 shows a case where the winding start groove of the first coil group of low speed and high speed elongation phases is positive 1.

Next, the effect will be explained.

In FIG. 1, when the switch SW is turned on and the switch SW is open, the busbar voltage is applied to the low speed winding, and the motors M1 and M2 are operated. At this time.

Although the high-speed side switch SW is open, the high-speed windings of the magnetic motors M1 and M2 form a closed circuit between the three-phase terminals.

That is, one is U,, -V□-V□-Ul! −”
12 m The other one is UKt-W,, -W,, -U,,
-〇8. , change "vlt-w, , -w, , -v, , -v□
It is a closed circuit.

As mentioned above, during low-speed operation, the high-speed winding, which serves as an idle winding, is excited by the magnetic poles (12 magnetic poles in the explanation) generated in the low-speed winding. As a result, in the case of a pole change motor in which the winding start groove of the first coil group of the slow-speed winding and the high-speed winding is in the armature core group 1, as shown in FIG. 2 as an embodiment of the present invention.

The U-phase induced voltage is zB = 4 (c
rIil, 2σ-ooi3QQ''), and since this is a three-phase balanced winding, for the other V and W phases [
will be exactly the same.

Here, as described above, in all motors of the present invention, the winding start groove of the first coil group of the slow-speed winding and the high-speed winding is the armature core groove-1. In other words, since the winding positions of the low-speed winding and the high-speed winding are exactly the same, the induced voltage of the high-speed winding, which acts as an idle winding, is the same value for all phases of other motors, and is vector-like. It is also the same value. Therefore, no potential difference occurs in the closed circuit between the three-phase terminals of the high-speed winding formed by connecting these motors together. Therefore, no circulating current flows in the closed circuit.

In this way, the winding position relationship of the low-speed windings and high-speed windings of all motors in the armature core groove of multiple two-speed pole-change motors with built-in double windings of the same rating. By making them exactly the same, (1) the induced voltage values of the idle windings of all motors can be made the same value, and the potential difference in the closed circuit constituted by the idle windings is made zero.

(2) As a result, heating of the winding and current balance on the excitation winding side (-side) are maintained without inducing a circulating current in the closed circuit.

(3) Accurate protection coordination of system circuits is maintained.

(4) No extra switch is required. Therefore, the configuration of the control circuit related to operation is simplified and operation becomes easy.

It has many advantages such as.

Embodiment 2 FIG. 3 shows the main part of the second embodiment. The system connection diagram for the pole-converting motor with this coil arrangement is the same as that shown in FIG. 1 of the first embodiment, so please refer to this diagram as well.

In this second embodiment, the winding start groove of the low-speed winding is shifted by one groove from that in the first embodiment. The rest is as in Example 1.

Next, the effect will be explained.

Even in the case of all motors with windings shifted by one groove, the sum of the induced voltages of the υ phase Σg4 is Σ as described in the explanation of the conventional example.
E = 4 (Cluster 6C - Fish 240°), which is different from the case shown in Fig. 2, but between electric motors that are connected and operated in the same way, the values are the same for all phases, and the values are also the same in terms of vectors.

Therefore, no potential difference occurs in the closed circuit between the three-phase terminals of the high-speed winding constructed by connecting these motors together.

Therefore, no circulating current flows in the closed circuit. Therefore, the same effects as in Example 1 are achieved.

The present invention is based on the embodiments described above and shown in the drawings.
For example, (1) the same method is possible even if there are two dual-winding, three-speed, pole-change motors C, although the present invention is not limited thereto. That is, in the case of a pole change motor in which one winding provides one speed and the other winding provides two speeds.

(2) When operating a pole change motor that obtains three speeds using triple windings, all windings at the same speed are operated at once.

etc. can also be used as a modification of the present invention.

〔Effect of the invention〕

As explained above, according to the present invention, the following effects can be obtained.

(Li) By setting the induced voltages of the idle windings of multiple motors to the same value, it is possible to reduce the potential difference in the closed circuit created by collectively connecting the idle winding terminals of each motor to zero, and Therefore, all common-mode terminals of each motor can be connected together.As a result, conventionally, each motor,
required for each winding. Switches are no longer required, and no matter how many electric motors are operated, the use of only two switches enables batch balanced parallel operation from bus to busbar.

(2) Since there are only two main switches, the motor control circuit is extremely simplified, the number of components of the control circuit is drastically reduced, and the control itself is also extremely easy (2).

(3) A closed circuit that is created when a conventional switch inserted in each motor and each winding breaks down due to trouble, etc., induces circulating current, causing coil burnout, increased loss, and - Although the unbalance of the secondary current causes a phenomenon in which the protection coordination of the circuit is not maintained, the present invention allows balanced parallel operation without overcoming these drawbacks.

Like the above? Two inventions (the effects of the two inventions are extremely large).

[Brief explanation of drawings]

11th! ! O is a system connection diagram showing the first embodiment of the parallel operation pole number conversion motor device of the present invention, Fig. 2 is a winding arrangement diagram for the groove of the motor in Fig. The winding layout diagram of the electric motor, Figure 4 is the system connection diagram of the conventional example,
5 is a winding arrangement diagram and a low-speed side magnetic pole formation diagram for @6 of the electric motor in FIG. 4, and FIG. FIG. 7 is a connection diagram showing one phase of the coil shown in FIG. 6. FIG. Person... bus bar, SW,... low speed side main switch, SW,
...High-speed side main switch, Ml...Nll motor, M2
...Nl12 electric motor s UIx, vlj* ”11
”・11 & 11 motor low speed winding each phase terminal, U,,, V
□, Wl,...FkLl Motor high-speed winding each phase terminal, U
□, V□, W□...Floor 2 motor low speed winding each phase terminal, U
tt* Vote Wet 42 '4 Motor high speed winding each phase terminal, 1 to 36...' @ Machine core groove dove, O...High speed winding U phase, Δ...High speed winding V phase 1 port ...High speed winding W phase, u'11 uQ I uSsu'4...High speed winding lower phase coil, ◎...Low speed winding U phase, Δ...
・Low speed winding V phase 1 port・・・Low speed winding 2 phase 1 port. s, @pole, ult "* e 'It u4"" High-speed winding U-phase coil group, 'Iev!*Ma3.v, ... High-speed winding V-phase coil group, "1 v Wt * 114 I
iv4...High-speed winding W-phase coil group. Agent Patent Attorney Mr. Inoue Figure 1 Figure 4

Claims (1)

[Claims] In a pole number changing motor device that operates multiple two-speed pole number changing motors with built-in double windings in parallel on the same bus,
The groove storage positions of the coils of the low-speed and high-speed armature windings of each motor are all the same, and the low-speed and high-speed winding ends are bundled together to connect the low-speed switch and the high-speed switch. A parallel operation pole number conversion electric motor device characterized in that it is connected to the same bus bar through a speed switch.