JP3105231B2 - 2 stator induction motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention has a single rotor composed of two rotor cores and two stators, and faces two stators. The present invention relates to a two-stator induction motor capable of generating a phase difference between rotating magnetic fields generated around a rotor conductor and generating a high torque from a low speed to a high speed.

[Conventional technology]

For torque control and speed control of an induction motor having a plurality of stators, there is a method known in the prior art for changing a phase difference between stators. The method of changing this phase difference is to provide a phase difference by rotating the stator as mechanical, to provide some kind of phase difference by changing the connection of the stator winding as electrical, Further, there are various kinds such as those in which star delta switching is combined.

The above methods use various methods depending on the load or application, such as when the torque and speed of the induction motor are freely changed to cope with the load, when the speed at startup is smoothly increased, etc. .

[Problems to be solved by the invention]

The present invention responds to a load by providing several kinds of stepwise phase changes, and can be said to be an electric method.

The electrical method in the prior art is performed by switching the connection of the stator windings, and the phase difference can be implemented at electrical angles of 0 °, 60 °, 120 °, and 180 °. It was over ten and expensive.

Further, some induction motors are provided with a star-delta switching device for the purpose of improving the startability, but the wiring between the star-delta switching device and the motor is complicated despite a single stator. Was. In other words, the star-delta switching device cannot be provided directly on the motor because the device is large and the switching depends on human power or another power source, and the wiring between the star-delta switching device and the motor is structurally Many large capacity cables were required.

In most cases, switches or star-delta switching devices that switch the phase difference are switched by opening and closing the contacts. Temporary disconnection of the load current caused by this opening and closing causes fluctuations in the generated torque, and is driven by the operation of the switch. Was shocking the device.

SUMMARY OF THE INVENTION An object of the present invention is to provide an inexpensive two-stator induction motor that has the minimum required number of switches required for switching while having the torque characteristics at the phase difference, and is free from shocks due to switching.

[Means for solving the problem]

In order to solve the above-mentioned problem, the present invention has two rotor cores which are axially mounted on the same rotation shaft with a space or a non-magnetic core interposed therebetween, and communicates with the two rotor cores. A rotor integrally formed by providing a plurality of conductors; two stators arranged side by side to face each of the two rotor cores; and one of the two stators A voltage phase shifter for causing a phase difference between a rotating magnetic field generated around the rotor facing the stator and a rotating magnetic field generated around the rotor facing the other stator; 2 In the stator induction motor, the voltage phase shifter may be configured such that the windings of the two stators are connected in series delta connection, and the phase difference of the rotating magnetic field between the windings of the two stators is 0 °. And a second connection on / off switch having a phase difference of 120 ° between the first connection on / off switch and the rotating magnetic field. It was configured to have.

Furthermore, according to the present invention, the voltage phase shifter sets the windings of the two stators to a serial delta connection, and sets the phase difference of the rotating magnetic field between the windings of the two stators to 0 °. First
In parallel with the second connection on / off switch and the first and second connection on / off switches having a phase difference of 120 ° between the connection on / off switch and the rotating magnetic field, and having a phase difference of 0 ° on the parallel connection with the first and second connection on / off switches.
In order to solve the problem, a third connection on / off switch which can be switched to both of 120 ° is provided, and a switch of a semiconductor element is interposed between the third connection on / off switch and the stator winding. Means.

In the space between the two rotor cores or in the non-magnetic core portion, a connecting member for mutually resistance-short-circuiting any one of the plurality of conductors adjacent to each other is provided, and the voltage phase shifter is , Each of the switches, a switch of a semiconductor element, and a control unit for controlling the opening and closing of the switch by an arbitrary signal.
This is a means for solving the above-mentioned problem by being integrated with the stator induction motor.

(Operation)

The first operation of the present invention will be described. Each of the first connection on / off switch and the second connection on / off switch is
The phase difference between 0 ° and 120 ° is provided between the stators. Therefore, when only the first switch is closed and the power is turned on, the phase difference is 0 °, and conversely, when only the switch is closed and the power is turned on, the phase difference is 120 °. When the first switch and the second switch are simultaneously closed and the power is turned on, the phase difference becomes 60 °. That is, three phase differences of 0 °, 60 °, and 120 ° can be provided by the first and second switches.

By the way, the phase difference generated by the present invention is 0 °, 60 °, 120 ° as described above, and the connection of the stator winding at each phase difference is as follows. That is, the phase difference 0 ° and 12
At 0 °, the stator windings are connected in series and the whole is connected in a delta configuration.When the phase difference is 60 °, the stator windings are connected in parallel to form a star configuration. It becomes a connected parallel star connection. This means that the shared voltage of each winding in parallel delta connection is 1.15 times higher than the shared voltage in serial delta connection, and the torque characteristic proportional to the square of the voltage is the torque characteristic of 0 ° phase difference. The torque characteristic at a phase difference of 60 ° is larger. However, various characteristics such as the current value and the efficiency at the rated rotation speed are preferably at the phase difference of 0 °, and are finally switched to the phase difference of 0 ° for use.

The above works in the following manner. First, when the second switch is turned on and the power is turned on, the phase difference between the stators is
Start up at 120 ゜. The load is activated by a torque characteristic curve with a phase difference of 120 °. Next, after an elapse of an arbitrary time or at an arbitrary rotation speed, the first switch is turned on and the phase difference is changed to 60 ° while the second switch is kept as it is. Load is phase difference 60
The motor is further accelerated by the torque characteristic of ゜ and the rotation of the motor is increased. Finally, after an elapse of an arbitrary time or an arbitrary rotation speed (in this case, a rotation speed lower than the rotation speed at the intersection of the load torque and the torque characteristic curve with a phase difference of 0 ° or a lower rotation speed). When the second switch is released and the second switch is released, the phase difference becomes 0 °, and the load is driven by the torque characteristics of a general induction motor.

As described above, the phase difference can be changed in three stages only by opening and closing the first and second two connection opening / closing switches, and the number of contacts is far smaller than that of the related art. Also, as described above, the first
Since either one of the first and second switches is always on, the contact capacity of the first and second switches can be reduced, and the generated torque does not become zero without interrupting the load current. Furthermore,
Since there is a stage in which both the first and second switches are turned on and used, even if one or both switches are turned on due to an accident of the open / close switch, for example, welding of a contact or the like, an electrical accident may occur. Never.

As a second operation, a third connection on / off switch capable of switching the phase difference of the rotating magnetic field between both 0 ° and 120 ° is provided in parallel with the first and second connection on / off switches,
The operation of a switch having a semiconductor element interposed between the third connection on / off switch and the stator winding will be described.

Here, the switch of the semiconductor element is an element capable of steplessly controlling the disconnection and conduction depending on the firing angle. A general process from start to operation will be described step by step. The switch of the semiconductor element (hereinafter referred to as the semiconductor switch) is in a non-conductive state (ignition angle
180 °), the third connection on / off switch is switched to a phase difference of 120 °, and the firing angle of the semiconductor switch is gradually changed from non-conductive to conductive (firing angle 0 °). The voltage gradually increases, and gradually starts with a torque characteristic having a phase difference of 120 °. When the firing angle of the semiconductor switch is turned on, after turning on the second connection switch (phase difference 120 °), the firing angle of the semiconductor switch is interrupted and the third connection switch is set to 0 ° phase difference. Switch. Next, when the firing angle of the semiconductor switch is gradually changed from non-conduction to conduction, a series delta connection with a phase difference of 120 ° by the second connection switch and a series delta connection with a phase difference of 0 ° by the third connection switch. Appear simultaneously on the stator winding, and the stator winding gradually changes to a parallel star connection with a phase difference of 60 °.

This is as described in the above-mentioned operation, and is equivalent to the case where the first connection on / off switch (phase difference 0 °) and the second connection on / off switch (phase difference 120 °) are simultaneously turned on.

If the firing angle of the semiconductor switch is made conductive as it is, the torque characteristic of the phase difference of 60 ° exceeds the torque characteristic of the phase difference of 0 ° as described above, so when the firing angle of the semiconductor switch approaches the conductive state, When the second connection on / off switch (phase difference 120 °) is opened, the operation of the second connection on / off switch (phase difference 120 °) disappears and the stator winding has a phase difference of 0 ° by the third connection on / off switch. The plurality of stator induction motors reach operating torque by subsequently turning on the firing angle of the semiconductor switch.

Thereafter, when the first connection on / off switch is turned on and the firing angle of the semiconductor switch is interrupted, the operation is performed with an operation torque of a phase difference of 0 ° by the first connection on / off switch. This means that it is possible to change the driving torque by setting the third on / off switch to the phase difference of 120 ° after reaching the driving torque and controlling the firing angle of the semiconductor switch between non-conduction and conduction. Become.

As described above, the first effect is that the change of the phase difference is made in multiple stages and the change of the phase difference is made step by step with the minimum number of open / close switches. Became possible.

In the second operation, in addition to the first operation, the change in torque is not stepwise, but is gradually changed from a phase difference of 120 ° to a phase difference of 0 °. This makes it possible to improve the startability and switch the phase difference without shock.

Next, in the space or the non-magnetic core portion between the two rotor cores of the two-stator induction motor, a connection for mutually resistance-short-circuiting any adjacent one of the plurality of rotating conductors. The operation when a material is provided will be described.

First, if a phase difference due to the first or second action is provided without a connecting member, as the phase difference increases, the voltage induced in the rotor decreases and the generated torque decreases. Further, when the phase difference is made 180 ° by another method, the voltage induced in the rotor finally becomes zero. The change in the torque characteristics at this time indicates the same change in the torque characteristics as in the primary voltage control. In this case, the present invention has a great effect that a simple open / close switch can be used instead of an expensive device required for primary voltage control.

On the other hand, when a connecting member is provided, if a phase difference is provided by the first or second action, a current flows through the connecting member as the phase difference increases, and the phase difference is reduced to 180 ° by another method. Then, current flows to the rotor conductor via the connecting member. That is, it has a torque characteristic of a phase difference of 180 °, and the change in the torque characteristic due to the change in the phase difference shows the same torque characteristic as the proportional change.

However, the operation has been described in the case where the connecting members are provided between all the adjacent rotor conductors and short-circuited with each other. However, the resistance is short-circuited between arbitrary arbitrary adjacent ones of the plurality of rotor conductors. When the connecting member is provided, as the phase difference increases, the current flows through the connecting member in the same manner as described above, but since the connecting member is provided between arbitrary conductors, the current flowing is limited, and the transition is proportional to the primary voltage control. Have a unique torque characteristic due to the interaction of

By the way, if the phase shift device is provided with a connection / opening / closing switch, a semiconductor switch, and a control unit for controlling the opening / closing of the semiconductor switch by an arbitrary signal, it is possible to change the phase difference and thereby change the output torque characteristics. It becomes possible to cope with load fluctuations, and for example, it becomes possible to automatically control an induction motor using a signal such as a rotation speed, a load current, or simply a timer. It is common knowledge that a general induction motor requires an expensive and large device to change the rotation speed and torque.

The number of wires required for connecting the induction motor of the present invention to a power supply and connecting a phase shifter including first and second connection changeover switches is three in the case of a three-phase specification, and the number of wires is three. Needs nine in total. When the phase shifter is provided on the power supply side, six wires are required from the motor side and three wires are required from the power supply side, and it is difficult to deal with the field. Here, by integrating the phase shifter with the electric motor, three wires from the power supply side are sufficient. When the size of a general motor is increased, the wiring work of six wires becomes complicated for Y- △ starting.
According to the present invention, the torque characteristic of the induction motor is changed by a phase shifter using two switches, and the number of wires is only three as a power source by integrating the phase shifter with the induction motor. Therefore, even if the motor becomes large, it is sufficient to check only the three wirings and the rotation direction of the power supply, even if the motor becomes large, so that the cost of wiring materials can be reduced and the work can be simplified.

〔Example〕

The present applicant has already described in detail the structure and operation of an induction motor comprising a plurality of stators, which is a part of the structure of the present invention, as Japanese Patent Application No. 61-128314.

Referring to FIG. 1, one embodiment of an electric motor which forms a part of the configuration of the present invention will be described. Reference numeral 1 denotes a two-stator induction motor according to the present invention, and the induction motor 1 has the following configuration. The rotor cores 2 and 3 made of a magnetic material are mounted on the rotor shaft 4 at arbitrary intervals. A non-magnetic core 5 is provided between the rotor cores 2 and 3, or a space is provided between the rotor cores 2 and 3. Rotor core
A plurality of conductors 6 are provided in communication with 2, 3 to form an integral rotor 7, and both ends of the plurality of conductors 6 connected in series are short-circuited by short-circuit rings 8,8. . In this embodiment, the conductors 6 provided on the rotor 7 are the rotor cores 2,.
In the portion of the non-magnetic core 5 between the three, each of the plurality of conductors 6 is connected via a connecting member 9 through which a current flows due to the phase difference of the rotating magnetic field.

A first stator 12 and a second stator 13 provided with windings 10 and 11 on outer portions facing the rotor cores 2 and 3 are arranged side by side on a machine frame 14, and the first stator 12 and the second stator 13 is fixed to the machine frame 14.

The connection between the windings 10 and 11 of the first stator 12 and the second stator 13 is a serial connection.

 Next, a first embodiment of the present invention is shown in FIGS.

FIG. 2 is a connection diagram of the present invention. One terminal of each coil of the stator windings _{11 (U 1, V 1,} W 1) a source A through a power switching device S _0, B, the other terminal with connecting to C (X
_1, Y _1, Z ₁₎ and is connected to one terminal of the connection opening and closing the switch S _1. One terminal of each coil of the stator winding 100 (U
₂ , V ₂ , W ₂ ) to the other terminal of the connection on / off switch S ₁ , and the other terminals (X ₂ , Y ₂ ,
Z ₂ ) is connected to a power supply so that the stator winding 10 and the stator winding 11 are in a series delta connection. Also, one of the connection opening and closing the switch S ₂ is connected in parallel to one terminal of the connection opening and closing the switch S _1, the other, the stator winding 10 and stator windings 11 and is electrically 120 ° phase difference And connected to one terminal (U ₂ , V ₂ , W ₂ ) of the stator winding 10.

The operation in the above configuration will be described. First, when the connection switching switch S ₁ (hereinafter referred to as switch S ₁ ) is closed and the power switching device S ₀ is closed, the stator winding 11 and the stator winding 10 are connected in series. This is shown in FIG. That is, the coils U _{1 to} X ₁ of the stator winding 11 and the coils U _{2 to} X ₂ of the winding 10 are in series, and at this time, the phase difference between the shared voltages of the two coils is 0 °.
At this time, the shared voltage of each coil is 1/2 of the power supply voltage E _AB . The same applies to other phases.

Next, when the connection open / close switch S ₂ (hereinafter referred to as switch S ₂ ) is closed while S ₁ is closed, the phases of the switch S ₁ are short-circuited, so that the stator winding 11 and the stator winding 10 are connected in parallel to the power supply. It becomes Y connection. This is shown in FIG. Vector diagram of the shared voltage E ₁ 'of share of the coil U ₁ to X ₁ voltage E ₁ and the coil U ₂ to X ₂ the fourth
As shown in FIG. 2, the phase difference is switched to 60 °. here
E _AB indicates the line voltage of the power supply.

At this time, the magnitude of E ₁ is It has become. Although this voltage rise is within the allowable range of the power supply voltage fluctuation and does not cause any problem, this voltage rise has an advantage that the torque characteristics are improved.

Then shared voltage of Releasing the only switch S ₁ divided voltage of each coil and as winding 10 described above becomes 5 11 12
It has a phase difference of 0 ° between the stators. At this time, the shared voltage of each coil is 1/2 of the power supply voltage.

It is possible to provide a phase difference of three stages by two connection off switch of the switch S ₁ and switch S ₂ as described above.

By the way, when the above-mentioned phase difference is 60 °, that is, the switch S ₁
And between the phases of the switch S ₁ by the switch S ₂ is in a state in which the switch S ₂ is turned is in a short-circuit state, therefore accidents such even by short-circuit other causes of contact failure or the like to burn the electric motor does not occur.

Further, when the switches S ₁ and S ₂ for switching the phases are opened and closed, one of them is always in a closed state, so that there is no interruption of the load current by opening and closing the switches. Furthermore, since there is no interruption of the load current and the gap voltage becomes half of the power supply voltage, it is possible to use a small electrical capacity of the connection on / off switch, and the voltage phase shifter using the switches S ₁ and S ₂ can be used. Can be reduced in size.

 FIG. 6 is a connection diagram showing a second embodiment of the present invention.

One terminal U ₁ , V ₁ , W ₁ of each coil of the stator winding 11 is connected to a three-phase power source A, B, C, and the other terminal X ₁ , Y ₁ , Z ₁ is connected to a _first terminal.
Of is connected to one terminal of the connection opening and closing the switch S _1. Also, one terminal U ₂ , V ₂ , W ₂ of each coil of the stator winding 10 is connected to the other terminal of the connection on / off switch S ₁ , and the other terminal X ₂ of each coil of the stator winding 10 is connected. , Y ₂ , Z ₂ to the terminals V ₁ , W
_1, is connected to the U _1. That is, each coil of the stator winding 11 and 10 are connected so as to be connected in series △ after the input of the connection opening and closing the switch S _1.

The one of the second connection opening and closing the switch S ₂ is connected in parallel to one terminal of the connection opening and closing the switch S _1, the other stator winding
10 are connected to one terminal V ₂ , W ₂ , U ₂ . That is connected so that the phase difference angle of the rotating magnetic field to produce a rotating magnetic field generated with the stator winding 11 by introduction of only connection closing switch S ₂ of the stator windings 10 is connected to a 120 ° series △ an electrical angle It is.

A third of the B contact of the connection opening and closing the switch S ₃ is connected via a switch T of the semiconductor device connected in parallel with the connection opening and closing switch S _2, A contact of connection closing switch S ₃ via a switch T of the semiconductor element connection It is connected in parallel with the opening and closing switch S _1. Wherein the B contact magnet switch S ₃ (not shown) is closed and the contacts at the time of non-excitation, A contacts the contact is opened when the magnet switch S ₃ is non-excited and vice versa When the magnet is excited, the B contact is opened and the A contact is turned on.

Here the switch S ₃ is shows an integral closing switch including a contact A, B contacts, it is also possible to configure the switch S ₃ in two separate switches.

The operation in the above configuration will be described. The description will be made in the order from start to operation. First, when the three-phase power supplies A, B, and C are used, the connection open / close switches S ₁ , S ₂ , and S ₃ (hereinafter, switches)
Since S _1, S _2, and S ₃₎ is a magnet not excited but now in S ₁ and S ₂ are open, in a state where B contact of the switch S ₃ is closed, the stator windings 11 The stator winding 10 is provided with a phase difference of 120 ° and is connected in series with the power supply via the semiconductor element T. This is shown in FIG. If the firing angle is set to 0 ° using a triac or a thyristor connected in parallel with the opposite polarity to the semiconductor element T, the sharing voltages E ₁ , E ₂ , E ₃ , E ₁ ′, E ₂ ′ and E ₃ ′ are 1/2 of the line voltage of the power supply, and the sharing voltage E ₁ of the coils U _{1 to} X ₁ of the stator winding 11 and the sharing of the coils U _{2 to} X ₂ of the stator winding 10 The phase difference of the voltage E ₁ ′ is θ =
120 ゜. The same applies to other phases. Therefore, the phase difference θ between the two rotating magnetic fields generated by the stator windings 11 and 10 is 120
It becomes ゜.

Further, if the firing angle of T of the semiconductor element is set to 180 °, no current flows in each coil, so that the shared voltage of each coil becomes zero and the torque acting on the rotor is zero.

Therefore, first, when the firing angle of the semiconductor element T is started from 180 ° and the firing angle is gradually reduced, the shared voltage of each coil gradually increases, and the torque acting on the rotor gradually increases. When the torque becomes larger than the load torque, the rotor starts to rotate, and when the firing angle is set to 0 °, the rotation speed increases to a slip l at the intersection of the load characteristic and the torque characteristic of θ = 120 ° shown in FIG. As described above, since the torque gradually increases from zero by controlling the firing angle, a smooth start can be performed.

Next, the following operation is performed to further increase the rotation speed from the speed corresponding to the slip l in FIG.

I.e. 180 ° of the firing angle of the semiconductor element T to close the switch S ₂ to excite the magnet switch S ₂ of Figure 6. Next, the magnet of the switch S ₃ is excited to switch S ₃
Is opened and the A contact is closed. FIG. 9 shows the connection state of each coil at this time.

That is, since the firing angle of the semiconductor element T is 180 ° and no current flows through the semiconductor element T, the connection state is exactly the same as when the firing angle of the semiconductor element T is set to 0 ° in FIG. The rotation speed does not change more than the speed corresponding to the slip l in FIG.

Next, when the firing angle of the semiconductor element T is set to 0 ° in the connection state of FIG. 9, the terminals X ₁ and U ₂ , Y ₁ and V ₂ , and Z ₁ and W _{2 of} the coil are short-circuited. Therefore, the shared voltages E ₁ , E ₂ , E ₃ ,
E ₁ ′, E ₂ ′, E ₃ ′ are as shown in FIG.

That shared voltage E ₁ of the coil U ₁ to X shared voltage E ₁ of ₁ and coil U ₂ to X ₂ 'is a line voltage of the power supply And the phase difference θ is 60 °. The same applies to other phases. Therefore, the torque characteristic at this time is represented by θ =
It has a characteristic of 60mm.

However, the torque characteristic of the phase difference of 60 ° exceeds the torque characteristic of the phase difference of 0 ° as shown in FIG. Therefore, when shifting from the phase difference 120 ° to the phase difference 60 °, the firing angle of the semiconductor element T is stopped at δ ゜ close to 0 ° in the connection in FIG. 9, that is, stopped at the phase of the slip m in FIG. When the firing angle is controlled as described above, the rotation speed increases from the slip 1 in FIG. 8 to a speed corresponding to the slip m.

Next, the following operation is performed to further increase the rotation speed from the speed corresponding to the slip m in FIG.

That is, when off while switches S ₂ arc angle δ ° in terms of the semiconductor device T from the position of the sliding m, connection shown in FIG. 9 is
It changes as shown in FIG.

When the firing angle of the semiconductor device T in this connection state 0 °, shared voltage E ₁ of the coil U ₁ to X shared voltage E ₁ of ₁ and coil U ₂ to X ₂ 'is 1 of the line voltage of the power supply / 2, and the phase difference θ
Becomes 0 °. The same applies to other phases. Therefore, the torque characteristic at this time is the characteristic of θ = 0 ° in FIG. 8, and the rotational speed is a speed corresponding to the slip n in FIG.

Therefore, in the connection state shown in FIG.
If it is controlled from ゜ to 0 °, the rotation speed becomes the slip m in FIG.
The speed increases to a speed corresponding to the slip n. The speed corresponding to the slip n is the speed in the highest operating state.

Then by closing the switch S _1, the firing angle of the semiconductor element T 18
0 When opening the ° switch S ₃ is changed, the semiconductor element T
Irrespective of the above, the connection is made by a simple open / close switch, so that the circuit during operation is very simple.

In operation, the semiconductor element T and a switch S ₃ B
By acting on the contact point, an intermediate torque characteristic between a phase difference of 0 ° and a phase difference of 60 ° can be derived, and acceleration / deceleration during operation is possible. This is a torque characteristic of 60 ° phase difference,
The control is performed by controlling the firing angle of the semiconductor element T so as to include a torque characteristic having a phase difference of 0 °.

The operation of the first, second, and third opening / closing switches S ₁ , S ₂ , and S ₃ ,
Control of the firing angle of the switch T of the semiconductor element and the stator winding
FIG. 12 summarizes the relationship between the phase difference θ between the two rotating magnetic fields 11 and 10 and the rotational speed in a table.

The slightly increased shared voltage at θ = 60 ° has the advantage of bringing the torque characteristic closer to the characteristic of the proportional transition.

In the above description, the firing angle of the semiconductor element T is controlled in all of the semiconductor elements T of each phase shown in FIG. 6, but an arbitrary angle is controlled in the range of θ = 120 ° to 60 °. The firing angle of the semiconductor element T of one phase may be maintained at 180 °. This is useful for preventing mutual interference between the phase semiconductor elements T.

When the semiconductor elements T of the respective layers are constituted by thyristors connected in parallel with opposite polarities, S ₁ , S ₂ , and S ₃ are connected in parallel in the off state, that is, in the connection state shown in FIG. If the firing angle of one of the thyristors is maintained at 180 ° and the firing angle of the other thyristor is set to 0 °, the current flowing through each coil becomes a half-wave rectified current and includes a DC component. The rotor is braked.

Therefore, if the firing angle of one thyristor of the thyristors connected in parallel with the opposite polarity is maintained at 180 ° and the firing angle of the other thyristor is controlled, the DC current flowing through the coil is controlled, so the rotor The brakes can be controlled.

In the first and second embodiments described above, it has been described on the assumption that each of the plurality of conductors 6 of the rotor is connected via the connecting member 9 through which current flows due to the phase difference of the rotating magnetic field. However, here, the connecting member 9 which can be similarly implemented
An example of a torque characteristic curve is shown in the case where there is no (A), and in the case where a connecting member is provided between adjacent arbitrary conductors 6 among a plurality of conductors of the rotor (B).

FIG. 13 shows a torque characteristic curve (A) when there is no coupling material and a torque characteristic curve (B) when a coupling material is provided between adjacent arbitrary conductors 6 among a plurality of conductors of the rotor. The torque characteristic curve (A) shows the same change in the torque characteristic as when the primary voltage control is performed, and the torque characteristic curve (B) shows the proportionality obtained by changing the primary voltage control and the resistance value of the secondary rotor. It shows a change similar to the torque characteristic obtained by summing up the transition.

In order to obtain a torque characteristic curve similar to the primary voltage control in the torque characteristic curve (A), an expensive power supply voltage control device for controlling the primary voltage was generally required. It became feasible with two open / close switches. Further, in order to realize the same torque characteristics as obtained by the sum of the primary voltage control and the proportional transition in which the resistance value of the secondary rotor is changed in the torque characteristic curve (B), the primary voltage and the secondary side Although it was common to require expensive and complex devices to control both the rotor's secondary resistance and the present invention, the present invention provides a method for controlling the rotor's secondary resistance between any adjacent one of a plurality of conductors of the rotor. The proportional transition of the secondary resistance value of the wound induction motor and the primary voltage control were performed simultaneously by the total of providing the connecting material and providing the phase difference with the two open / close switches. It has become possible to obtain a torque characteristic with a small current.

FIG. 14 shows an example of a connecting member provided on the rotor in order to obtain the torque characteristic curve (B) by a front sectional view of the rotor. The number and the mounting position of the connecting members are changed depending on the desired torque characteristics, the balance of the rotor, and the like.

By the way, as shown in FIG. 2 and FIG.
If the voltage phase device consisting of S ₁ and S ₂ is provided on the motor side, only three wires are required from the power supply side to the motor, and complicated wiring for starting Y- △ as seen in a general large motor is required. It is possible to provide an electric motor that can be operated at a high torque from a low speed to a high speed without need.

Next, control of the voltage phase device will be described with reference to FIGS. First, in the configuration of FIG. 15, the induction motor 1 is connected to a three-phase power supply 22 having a switching device. Further, the induction motor is integrally provided with a voltage phase shifter 20, and the voltage phase shifter is connected to a control unit 21 incorporating a sequence circuit including a timer. Next, the configuration of FIG. 16 will be described. The induction motor 1 is a three-phase power supply 22 having a switchgear.
Connected to The induction motor is integrally provided with a voltage phase shifter 20. The voltage phase shifter is connected to a control unit 23 composed of a hard logic circuit or the like, and the control unit 23 has a speed of the motor. The signal of the speed detector 24 for detecting is connected.

The above operation will be described. Each control unit 21, 23
Phase shifter by time limit by timer or signal of detector 24
This is for opening and closing the 20 connection opening / closing switches described above.
For example, in the case of the control unit 21, a general Y- △ start is about 10
Since switching is performed in seconds, starting with a phase difference of 120 ° and switching to a steady operation with a phase difference of 0 ° are performed, for example, with a phase difference of 12 °.
Start at 0 ° and set the time to switch to the next phase difference of 60 ° 4 to 5 seconds after starting, and set the time to switch from 60 ° to 0 ° from 4 ° to 5 ° after switching to 60 °. Thus, the voltage phase shifter 20 sequentially switches the phase difference from 120 ° to 0 ° in three stages. Needless to say, the above-mentioned time limit should be changed depending on the load.

In the case of the control unit 23, the control unit may include a simple logic circuit or a microprocessor as necessary, which is based on the current state of the art, but receives a signal from the detector 24, A circuit that converts the signal as necessary, a circuit that compares the converted signal with a predetermined reference value, a circuit that stores a predetermined reference value, and a signal output that outputs a signal by the previous comparison It will have a circuit and the like. The phase shifter 20 is sequentially switched by the signal of the signal output circuit to change the phase difference. Although the speed detector 24 is used here as the detector, means for detecting the state of the electric motor, such as a device for detecting the number of revolutions, is used.

By the way and timed in the control unit 21, and the predetermined reference value of the control unit 23, it is to be determined by the output of the load torque and GD ² and the electric motor. Further, each control unit is a simple one that only controls the opening and closing of the two connection on / off switches, and is used as a control unit of an induction motor having a three-stage phase difference for the voltage phase shifter of the connection on / off switch. It is also possible to incorporate and configure.

The torque characteristic of the multiple stator induction motor according to the present invention varies slowly from a phase difference of 180 ° to 120 ° depending on the characteristics of the motor. It can be used without much difference compared with four-stage phase control of {120, 60}, 0 ゜.

(Effect)

As described above, the setting of the phase difference of the two-stator induction motor
With a simple voltage phase shifter, it can be set in three stages, and the phase difference is three types for starting, medium speed, and operation. In particular, the motor is suitable for the purpose of improving the startability of the torque characteristic or the squared reduction torque characteristic and reducing the start-up time, and does not require an expensive control device such as an inverter. In addition, since the wiring to the motor is simply formed by integrating the voltage phase shifter into the motor, in the case of a three-phase power supply, three wires are required for the motor, and if anyone does not misunderstand the rotation direction, anyone can wire it. Is possible.

Therefore, it is possible to diversify the torque, expand the applications of multiple stator induction motors that can generate high torque from low speeds to the rated rotation range, and make a greater contribution to any field that requires high torque motors. Was.

[Brief description of the drawings]

1 is a side sectional view of a two-stator induction motor, FIG. 2 is a connection diagram of a phase shifter, FIG. 3 is a connection diagram at a phase difference of 0 °, and FIG. 4 is a connection diagram and a voltage at a phase difference of 60 °. Vector illustration of a
FIG. 5 is a connection diagram at a phase of 120 °, FIG. 6 is a connection diagram of the second embodiment, FIG. 7 is a connection diagram at a phase difference of 120 °,
8 is a torque characteristic curve diagram, FIG. 9 is a connection diagram in which a phase difference changes from 120 ° to 60 °, FIG. 10 is a diagram showing a parallel star connection with a phase difference of 60 °, and FIG. 11 is a phase difference diagram. FIG. 12 is a diagram showing the switching of each switch and the firing angle, and FIG. 13 is a torque characteristic curve (A) when there is no connecting material and a plurality of rotors. FIG. 14 is a diagram showing an example of a torque characteristic curve (B) in a case where a connecting material is provided between arbitrary conductors of a plurality of conductors. FIG. 14 shows a case where a connecting material is provided between any of a plurality of conductors of a rotor. FIG. 15 is a control block diagram by a timer sequence, and FIG. 16 is a control block diagram by a logic circuit. 1 ... 2 stator induction motor, 2, 3 ... rotor core, 4 ...
... rotor shaft, 5 ... non-magnetic core, 6 ... rotor conductor,
7 ... rotor, 8 ... short-circuit ring, 9 ... connecting material, 10, 11 ...
... stator winding, 12 ... first stator, 13 ... second stator,
14 ... machine frame, 20 ... phase shifter, 21 ... control unit, 22 ... power supply side, 23 ... control unit, 24 ... speed detector.

Claims (6)

(57) [Claims] 1. A semiconductor device comprising: two rotor cores which are axially mounted on the same rotation shaft with a space or a non-magnetic core interposed therebetween; and a plurality of conductors communicating with the two rotor cores are provided. An integrally formed rotor, two stators arranged side by side facing each of the two rotor cores, and one of the two stators has a rotation facing the rotor. A two-stator induction motor having a voltage phase shifter for producing a phase difference between a rotating magnetic field generated around the stator and a rotating magnetic field generated around the rotor opposed to another stator. A first connection on / off switch that sets the windings of the two stators in series delta connection and sets the phase difference of the rotating magnetic field between the two windings of the stator to 0 °;
A second connection on / off switch in which the windings of the two stators are connected in series delta connection and the phase difference of the rotating magnetic field is 120 °, wherein only a first connection on / off switch is closed. A phase difference of 0 °, a phase difference of 120 ° of a series delta connection in which only the second connection on / off switch is closed, and a phase difference of 60 ° of a parallel star connection in which the first and second connection on / off switches are closed simultaneously. A two-stator induction motor characterized in that: 2. A semiconductor device comprising: two rotor cores mounted on the same rotating shaft with a space or a non-magnetic core interposed therebetween; and a plurality of conductors communicating with the two rotor cores. An integrally formed rotor, two stators arranged side by side facing each of the two rotor cores, and one of the two stators has a rotation facing the rotor. A two-stator induction motor having a voltage phase shifter for producing a phase difference between a rotating magnetic field generated around the stator and a rotating magnetic field generated around the rotor opposed to another stator. A first connection on / off switch that sets the windings of the two stators in series delta connection and sets the phase difference of the rotating magnetic field between the two windings of the stator to 0 °;
A second connection on / off switch in which the windings of the two stators are connected in series delta connection and the phase difference of the rotating magnetic field is 120 °, and wherein the windings of the two stators are connected in series delta connection; A third connection on / off switch capable of switching the phase difference of the rotating magnetic field to both 0 ° and 120 °, a semiconductor element switch interposed between the third connection on / off switch and the stator winding, A two-stator induction motor, comprising: 3. A connecting member for short-circuiting any adjacent one of the plurality of conductors to each other in a space between the two rotor cores or in a non-magnetic core portion. The two-stator induction motor according to claim 1. 4. A two-stator induction motor according to claim 1, wherein the voltage phase shifter includes a control unit for controlling the connection of the connection switch by an arbitrary signal. 5. The two-stator induction motor according to claim 2, wherein the voltage phase shifter includes a control unit that controls opening and closing of a connection switch and a switch of a semiconductor element by an arbitrary signal. 6. A two-stator induction motor according to claim 1, wherein the voltage phase shifter is integrated with a machine frame of the two-stator induction motor.