JPH01126195A - Controller for varying speed for variable speed induction motor - Google Patents

Abstract

PURPOSE:To increase or reduce a varying speed according to the characteristic of a load and vary a speed smoothly or stop a device, by moving one of two stators rotationally and concentrically with a rotor, and by regulating the rotational speed. CONSTITUTION:A first stator 24 and a second stator 25 with windings 22, 23 applied to an external side section confronted with rotor cores 2, 3 are arranged in parallel with a mechanical frame 14. Between the mechanical frame 14 and the first stator 24, a slip bearing 26 is set, and the slip bearing 26 is fixed with a stop ring 28 fitted on the mechanical frame 14. The second stator 25 is fixed on the mechanical frame 14 with a fixing ring 27. The first stator 24 is moved rotationally and concentrically with a rotor 7 by the working of a miniature motor 30. Then, a voltage phase shifter is constituted by the rotational movement of the first stator 24, and the second stator 25.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a variable speed induction motor with good torque characteristics and efficiency and easy speed control.

[Prior art and its problems]

One way to control the speed of an induction motor is to change the power supply frequency. Although this method allows for continuous and wide-range speed control, it requires an expensive frequency converter, and in the process of converting alternating current to direct current and then back to alternating current using the frequency converter, harmonics and Radio waves are generated, which cause computers,
This may lead to damage such as malfunction of various other electrical control equipment or overheating of capacitors. Among these, countermeasures against harmonic interference can be taken by installing filters, but installing filters is costly. The method of varying the power supply frequency also has drawbacks such as generally insufficient performance at low speeds.

The method of controlling the speed by changing the number of poles of the motor during operation has the disadvantage that although it is possible to change the speed stepwise by changing the number of poles, it cannot control the speed to any desired speed over a wide range.

Yet another method of controlling speed by varying the voltage of the power supply is
Although speed control can be performed continuously, it has the disadvantage of poor efficiency, especially in the low speed range.

For wire-wound electric motors, there is a method of controlling the speed by changing the secondary resistance and changing the slip.

Although this method allows continuous speed control with relative ease, it requires maintenance and inspection due to wear and tear on the brushes because resistance is inserted into the rotor winding circuit from the outside via the brushes and slip ring. do. Note that in squirrel cage induction motors, speed control cannot be performed by changing the secondary resistance.

Techniques to deal with the above problems include, for example, Japanese Unexamined Patent Publication No. 54-2
It is disclosed in Japanese Patent No. 9005.

This device has two sets of stators each having independent stator windings facing the two sets of rotor cores, and is installed in common across the two sets of rotor cores, and is short-circuited at both ends. It is equipped with squirrel-cage conductors that are short-circuited to each other via a ring, and a high-resistance element that short-circuits the squirrel-cage conductors to each other at the center of the squirrel-cage conductors between two sets of rotor cores. This is a twin iron core squirrel cage electric motor characterized by having the windings shifted in phase by 180° and supplying power while matching the phases during operation after startup. This electric motor increases the starting torque and improves starting characteristics by shifting the phases of the stator windings by 180 degrees when starting, and during operation, the phases of the stator windings are adjusted to match the normal phase. It is unique in that it can be operated with torque characteristics. Therefore, in this electric motor, the phase shift of the rotating magnetic field can be limited to 09 and 1800 degrees, and although the starting characteristics are improved, since it is not originally a variable speed electric motor, it is difficult to handle loads that require speed changes. It is not suitable as a power source.

In addition, in the above-mentioned Japanese Patent Application Laid-open No. 54-29005, in order to alleviate the shock caused by sudden fluctuations in torque accompanying the transition from startup to steady operation, both stator windings are temporarily connected in series to the power supply circuit. Although providing an intermediate step for connection is described as an example, what can be achieved in this way does not necessarily enable speed change control.

Moreover, by switching to series, the voltage applied to the stator is halved, so the torque is reduced to 1/4, and this makes gear change control completely impossible, which is the main point disclosed in this publication. This is obvious from the fact that the purpose is not to change gears.

In short, although there is a description in JP-A-54-29005 that says "intermediate step of switching the stator windings to series connection and parallel connection with respect to the power supply circuit", this series connection is for the purpose of speed change. It is not a thing.

Further, the technology proposed in Japanese Patent Application Laid-open No. 49-86807 is an asynchronous electric motor having a squirrel cage rotor and a stator with polyphase windings, which includes conduction bars, short circuit end rings and ferromagnetic In those consisting of laminations, the stator consists of first and second winding sections, which sections are coaxially arranged adjacent to each other and to different parts of the rotor;
and is capable of being supplied with alternating current of the same frequency, and is characterized in that it is provided with means for varying the electromotive force induced in the rotor windings by means of the second winding section. Although it is possible to change the rotation speed by creating a phase difference between the two stator sections by mechanical or electrical means, it is possible to change the rotation speed when the phase angle between the two stator sections is in the same phase. It has a defect that the torque is small and the operation stops immediately when a load is applied, so it cannot be used for practical purposes at all, and it cannot be used as a power source for frequent starting and stopping when a load is connected. This left serious problems unresolved, such as the inability to do so.

[Purpose of the invention]

The present invention eliminates the drawbacks of the above-mentioned prior art and
In order to obtain a unique torque characteristic that cannot be achieved by the sum of the techniques disclosed in JP-A No. 4-29005 and JP-A-49-86807, the speed control range is wide and the speed control is stepless and arbitrary. The desired speed can be set at any variable speed, and it can be started with any torque, and the rated current that is almost the same as at the maximum rotational speed is applied over the entire speed range from the starting point to the maximum rotational speed. An object of the present invention is to provide a variable speed induction motor that has excellent torque characteristics and efficiency that are realized by cooling.

The variable speed induction motor of the present invention is used by being connected to a single-phase or three-phase power supply, and the rotor has a normal squirrel cage type, a double squirrel cage type, or a deep groove cage type.

It can be applied to any type of special squirrel cage type two-winding type. Note that the conductor used in the description of the present invention is a general term for the conductor installed in the squirrel cage rotor core and the winding wire wound around the wound rotor core.

[Means for solving problems]

In order to achieve the above technical problem, the present invention connects each of a plurality of conductors installed in each of a plurality of rotor cores to form an integral rotor, and A plurality of stators are arranged in parallel on the machine frame at the outer periphery facing each of the child cores, and each of the plurality of conductors is energized between the plurality of rotor cores when an arbitrary voltage is applied. A connecting member or a resistive member is used to short-circuit the stator, and at least one stator of the plurality of stators is provided with a drive device that rotates the stator concentrically with the rotor, so that the stator is freely rotatable. However, as a means of solving the problem, the drive device is provided with a rotation speed adjustment device for adjusting the rotation speed.

(Function) The present invention can reduce the voltage induced in the corresponding conductor portion of the rotor facing one of the plurality of stators and the voltage induced in the corresponding conductor portion of the rotor facing the other stator. The rotation speed of the rotor can be changed arbitrarily by creating a phase difference between the voltage applied and the rotation speed of the rotor, and large torque can be stably obtained.The rotation speed of the stator can also be adjusted to suit the characteristics of the load. You can arbitrarily adjust the rotational speed to increase or decrease the acceleration of the motor's rotational speed change to achieve smooth gear changes.Also, the speed can be changed smoothly by gradually increasing the speed from a stopped state until reaching a predetermined speed. It is possible to smoothly change speed or stop by adjusting the acceleration from a predetermined speed to a stopped state.

Embodiments Embodiments of the present invention will mainly be described with respect to a variable speed induction machine having a squirrel cage rotor, but the invention is not limited thereto.

Incidentally, in a wound rotor, the terminals of the windings wound around each of a plurality of rotor cores are connected for each phase to form an integral rotor winding. Of course, between the rotor cores, the phases of the rotor windings are short-circuited via a connecting member or a resistive member that conducts electricity when an arbitrary voltage is applied. It goes without saying that the windings wound around a plurality of stators may be connected in series or in parallel.

Embodiments of the present invention will be described based on FIGS. 1 to 11.

One embodiment of the present invention will be explained with reference to FIGS. 1 to 3. Reference numeral 1 denotes a variable speed induction motor according to the present invention, and the variable speed induction motor 1 has the following configuration. Rotor cores 2 and 3 made of magnetic material are mounted on the rotor shaft 4 with arbitrary intervals, and a non-magnetic core 5 is interposed between the rotor cores 2 and 3 or a space is provided between them. Each of the plurality of conductors 6 installed in the rotor core 2.3 is connected to the rotor core 2.
A plurality of conductors 6 are connected in series, and both ends thereof are connected to short-circuit rings 8.
, 8. Further, a plurality of ventilation cylinders 12 .
A plurality of ventilation holes 13 are formed perpendicularly through the outer circumference of the rotor 7. The conductor 6 installed in the rotor 7 is connected to the non-magnetic core 5 between the rotor cores 2 and 3 through a connecting member 9 that conducts electricity when a current with an arbitrary vector difference flows through each of the non-magnetic cores 5. That is, they are connected through a resistance material r made of nichrome wire, carbon-containing steel, conductive ceramic, etc. Bearing discs 15, 16 provided on both sides of the cylindrical machine frame 14 are connected to connecting rods 17 with nuts 18...
・Assemble integrally by tightening. Cooling impellers 19 and 20 are attached to both sides of the rotor 7, and both ends of the rotor shaft 4 are pivotally supported by bearings 21 and 21 fitted in bearing discs 15 and 16, so that the rotor 7 can be freely rotated. It's Toshide.

A first stator 24 and a second stator 25 having windings 22 and 23 on their outer sides facing the rotor cores 2 and 3 are arranged side by side in the machine frame 14, and the machine frame 14 and the first stator 24 are connected to each other. between sliding bearing 2
6 is installed, the sliding bearing 26 is fixed by a stop ring 28 fitted to the machine frame 14, and the second stator 25
is fixed to the machine frame 14 by a fixed ring 27. First stator 2
A gear 29 is fitted onto the outer circumferential surface of one side of 4. Machine frame 1
The drive gear 3 is attached to a small motor 30 fixed on the outer periphery of the drive gear 3.
The drive gear 31 is engaged with a gear 29 fitted to the first stator 24. With this configuration, the first stator 24 is rotated concentrically with the rotor 7 by the operation of the small motor 30. Thus, the rotation of the first stator 24 and the second stator 25 constitute a voltage phase shifting device.

Next, the configuration of the cooling device for the induction motor 1 will be explained. An air blowing port 34 and an air exhaust port 35 are bored in the outer periphery of the machine frame 14, and a blower 36 having a motor 37 is fixed to the air exhaust port 35, so that the air in the space 38 is circulated outside the machine frame 14. Also, cooling impellers 19 and 2 that rotate integrally with the rotor shaft 4
0. Air is taken in from the ventilation hole 32 and the side part 10°11,
It is provided to circulate air through the ventilation trunk 12 and the ventilation port 13. 33 is a vent for air circulation, which is located in the first part of the machine frame 14.
It is perforated in a portion facing the stator 24 and the second stator 25.

Next, the configuration of the means for detecting the rotational position of the first stator 24 will be explained with reference to FIG.

A magnetic body 39 is fixed on the outer periphery of the rotating first stator 24,
A rotational position detector 40 consisting of a plurality of magnetic sensors 40a to 40d is installed at any part of the machine frame 14 facing the magnetic body 39.
... are provided and communicate with a control device 42 that includes a rotational position indicator 41 that displays the rotational position of the first stator 24. 4
Reference numeral 3 denotes a solenoid for unlocking or locking the rotation of the first stator 24, and the rotation of the stator can be unlocked or locked by any known operating mechanism.

Another embodiment of the rotation mechanism and rotation position detection device will be described with reference to FIG.

A bearing 44 fixed to the machine frame 14 is rotatably provided with a rotating shaft 45 provided with a worm gear 46 that rotates integrally with the rotating shaft 45, and one end of the rotating shaft has a rotating shaft that rotates in forward and reverse directions. A pulse motor 47 for movement is provided concentrically with the rotating shaft 45, and the pulse motor 47 is fixed to the machine frame 14.

Next, the connection of the windings 22 and 23 wound around each of the first stator 24 and the second stator 25 will be explained based on FIG. 4.5. What is shown in FIG. The windings 22 and 23 provided on each of the second stators 24 and 25 are star-connected and connected in series to a power source. That is, the terminals A, B, and C of the winding 22 of the first stator 24 are connected to the commercial three-phase power supply A, B, and C, and the terminals a, b of the winding 22 are connected to the commercial three-phase power supply A, B, and C.
, c are connected to the terminals A, B, and C of the winding 23 of the second stator 25, and the terminals a, b, and c of the winding 23 are short-circuited and connected.

Moreover, the one shown in FIG. Second stator 24.25
The windings 22 and 23 are connected in series and delta-connected to a commercial three-phase power supply, but a detailed explanation thereof will be omitted. In addition, 7A in FIG.

7B shows the connection of the wire-wound rotor wound around the rotor cores 2 and 3.

The operation of the above configuration will be explained below.

When the windings 22 of the first stator 24 are energized from a commercial three-phase power source, a rotating magnetic field is generated in the stator 24, 25, a voltage is induced in the rotor 7, and a current is generated in the conductors 6 of the rotor 7. The flow causes the rotor 7 to rotate.

When the rotation R of the first stator 24 with respect to the second stator 25 is set to zero, each stator 24.25
There is no phase shift in the voltage induced in the conductor 6 of the rotor 7, and as will be described in detail later, no current flows through the resistive material r formed with the connecting member 9, so it is different from general induction. It has the same torque characteristics as an electric motor.

Next, a case will be described in which the small motor 30 is operated to rotate the first stator 24 by a phase angle of θ. The magnetic flux φ1 of the rotating magnetic field created by the first stator 24 and the second stator 25.
The phase of φ2 is shifted by θ with respect to the conductor 6 of the rotor 7, and therefore the first stator 24 and the second stator 25
The voltage 61. induced in the conductors 6 of the rotor 7 due to the voltage 61.
The phase of 62 will be shifted by θ. Now, using the voltage ω induced in the conductors 6 of the rotor 7 by the second stator 25 as a reference, the voltage is set to 4-8E. Here, S is slip and E is the induced voltage when slip is 1. At this time, the voltage sum 1 induced in the conductors 6 by the first stator 24 is 6+=SEεj·.

(E-Induced voltage when slip 1) What is shown in Fig. 6 is the slip S of the rotor 7 when the resistive material r... that short-circuits the plurality of conductors 6... is not installed. , which shows the relationship with the rotor input active power P, where the voltage phase is θ=O.

When , the effective power P is maximum, and 0°
When , it becomes smaller than that.

Here, if the resistance and inductance of the conductor 6 are R and L, and the angular frequency of the power source is ω, then the effective power P
The maximum value of appears when S = (R/ωL).

Since the active power P is proportional to the driving torque of the induction motor,
By rotating the first stator 24, the voltage induced in the rotor 7 can be adjusted and the speed of the rotor can be controlled steplessly, but as the phase difference increases, the torque decreases rapidly. It is of no practical use. .

Next, from the short circuit ring 8 of the conductor 6 of the rotor 7 to the connecting member 9
Let the respective resistances up to R1 and R2 and the inductance be 1. Let L2 be the angular frequency of the power source, ω be the angular frequency of the power source, and r be the resistance of the resistive material that short-circuits each conductor 6..., then the electrical equivalent circuit of the rotor 7 will be as shown in Figure 7,
Code I+.

12 and I3 indicate the current flowing through each branch.

Next, when converting the circuit shown in FIG. 7 into an equivalent circuit viewed from both stators 24 and 25 sides, it becomes as shown in FIG. 8, and RI=R
2, When θ-0° at Ll-12, l3-II-12
= 0, and no current flows through the resistor material r.

This means that when θ-〇°, the torque T is equal to the value when r is absent. Therefore, when θ=0°, it has the same torque characteristics as a conventional induction motor.

Next, when RI=R2, Ll-L2 and θ=180'', it becomes II--12, l3-II-I?-2I+, and in the conventional induction motor, the resistance of the rotor conductor 6... is RI= If R2-R is used, the result is the same as if R were increased to R+2r.

Due to the rotation of the rotor 7, the cooling impeller 19°20 opens the machine frame 1 through the ventilation holes 32 formed in the bearings 9115 and 16.
The outside air is sucked into the cooling impeller 19.20.
．． The second stator 24° 25 and the windings 22, 23 are ventilated and cooled, and the rotor cores 2, 3, conductors 6, . ...,
The connecting members 9, etc. are cooled to stably perform their respective functions. Also, 1st. The rotation of the second stator 24, 25 is carried out by rotating the small motor 30 in forward and reverse directions using a switch, but this is not limited to the small motor 30, and other forward and reverse motors may also be used, as well as gas, liquid cylinders, etc. Any drive device such as a servo mechanism can be used. The rotation of the stator is controlled to an arbitrary rotation speed in relation to the operation of the drive device that rotates the stator.

The drive device shown in Fig. 3 is a pulse motor 47 and a gear 2.
It consists of a worm gear engaged with 9, and a pulse motor 4.
7, the number of pulses sent from the control device @42 to the pulse motor 47 and the pulse interval are used to control the amount of rotation and the speed of rotation. In this embodiment, the worm gear also has the function of fixing rotation.

Next, the effect of connecting the windings 22 and 23 wound around the first stator 24 and the second stator 25 in series will be explained.

Since the windings 22 and 23 are connected in series, the windings 22 and 23 are connected in series.
A current is input from a commercial three-phase power source and flows between the windings 22 and 23, but if there is a difference in the resistance of each of the windings 22 and 23 or a difference in the capacitance of the stator 24 and 25. Also, independently of that, each winding 22.23
The magnitudes of the currents flowing in the conductors 6 of the rotor 7 are equal, so that the magnitudes of the currents flowing in the conductors 6 of the rotor 7 are equal from each of the first stator 24 and the second stator 25.
The re-stator is adjusted according to the effect that the magnitude of the current induced by the current flowing in 24
．． 25 to conductors 6 of the rotor 7 to be equal in magnitude, and the vector difference current caused by the phase difference in voltage between the stators 24 and 25 is Due to the synergistic effect of the force that inevitably flows through the resistive material r... which connects each of the plurality of conductors 6... to the connecting member 9, the slippage and slippage shown in FIG. Improved efficiency in terms of torque characteristics and the ability to generate large torque in each shift range.
Even when a load is connected, it is easy to start in each speed range, and it can be used to suit the starting characteristics of the load for smooth starting or high output, etc. Optimal support for power sources that frequently start and stop. As mentioned above, the speed of the rotor 7 is controlled only by controlling the phase shift by rotating the first stator 24 and increasing or decreasing the current flowing through the conductors 6 of the rotor 7. The rotational speed of the child 7 can be changed arbitrarily.

Note that the first stator 24 has windings 22 and 23 connected in series.
and the second stator 25 to the conductor 6 of the rotor 7, respectively.
・For the magnitude of the current flowing through the multiple conductors 6...
The ratio of the current that flows in a short circuit through the resistive material r... is determined by the value of Pθ (P - number of pole pairs, θ = phase angle), regardless of the resistance value and slippage of the resistive material r... (The above ratio is maximum when Pθ = π and becomes zero when Pθ = 0.) If Pθ is constant, the same slip as when the secondary insertion resistance of a general wound induction motor is constant. When it comes to torque characteristics, when Pθ becomes small, the ratio of current flowing through the conductor 6 of the rotor 7 becomes small, and reducing Pθ means reducing the secondary insertion resistance of a general wound induction motor. It will have the same effect. and re-stator 24
, 25, even if the phase difference θ is arbitrarily changed, depending on the selection of the slip value and the design of the resistance value of the connecting member 9, the rated current and rated torque characteristics of the maximum speed can be changed, respectively. It is possible to act almost simultaneously in the speed change range of . Also, 1st. Second stator 24.25
Even if the windings 22 and 23 of
Almost no voltage is induced from the stator to the rotor conductors 6..., and the windings 22.
23 are more efficient than those connected to the power supply in parallel,
The phenomenon is that the torque decreases.

In contrast to the above, the windings 2 of the first stator 24 and the second stator 25
2.23 are connected in parallel to a commercial three-phase power supply, the windings 22.23 of the first stator 24 and the second stator 25.
23 are the same, the voltages induced from each of the re-stators 24 and 25 to the conductors 6 of the rotor 7 are the same, and the phases of the voltages differ by Pθ,
... The current flowing through the resistance material r... with the connecting member 9 between them is (1/2) (Resistance material r
The current is approximately proportional to the resistance value of... However, in the conductor 6 of the rotor 7, in addition to the current flowing through the resistance material r... ) flows in a superimposed manner. (The above sum voltage is Pθ
= π is zero and becomes maximum when Pθ = 0, and the impedance of the rotor conductor is composed of the resistance of the conductor and the secondary leakage reactance, so it varies depending on the slip). Therefore, the current flowing in the conductor 6 of the rotor 7 The ratio of the current flowing between the plurality of conductors 6 through the resistive material r to the magnitude of the current varies depending on the slip and resistance value even if Pθ is constant, and when Pθ is constant, The slip and torque characteristics are the characteristics shown in Figure 10, which are a mixture of the characteristics when the secondary insertion resistance of a general wound induction motor is constant and the characteristics when the primary voltage of a general induction motor is controlled. Become. This characteristic is the first. Although the speed control range is narrower than the characteristic when the windings 22, 23 of the second stator 24, 25 are connected in series, it can be used in the case of a load with reduced torque characteristics. .

Next, one embodiment of automatic control of the variable speed induction motor 1 will be described with reference to the block diagram shown in FIG.

Input/output circuit 50. Control circuit 51. The rotor shaft 4 is connected to the input side of the control device 42, which includes an arithmetic circuit 52, a memory circuit 53, etc.
A speed detector 48 such as a tachometer generator equipped with a speed indicator 49 attached to the machine frame 14, a rotation position detector 40 for detecting the rotation position of the first stator 24, and a temperature detector attached at an appropriate position within the machine frame 14. A small motor 30. is connected to the output side of the control device 42. The motor 37 of the lit exhaust device 36 that cools and radiates heat from the conductor 6..., the connecting member 9, etc. A solenoid 43 is connected to the rotary speed setter 55 or a keyboard 56 to input the following control values into the memory circuit 53 of the control device 42 in addition to the rotary speed set value.

That is, the first stator 24 corresponding to the phase angle 0° to 180°
The detection value of the rotation position detector 40 that detects the rotation angle (0° to 180° in electrical angle), the speed control value that controls the rotation speed of the induction motor 1, and the Several types of start-up settings that match the start-up characteristics of the load and temperature sensor 5 are available.
A reference temperature setting value, etc. for controlling the motor 37 to increase or decrease with respect to the temperature detected by step 4 is input.

When the operation preparation key is input from the keyboard 56 at the start of operation, the rotation position detector 40 detects the current rotation position of the first stator 24, and also detects the starting characteristics of the load connected to the rotor shaft 4. In response to a signal output from the memory circuit 53 of the control device 42 according to a suitable starting setting value, the solenoid 43 is actuated to unlock the gear 29 fitted to the first stator 24, and the small motor 30 is activated. The small motor 30 is activated to rotate the first stator 24, and when it reaches the desired starting rotation position, the small motor 30 automatically stops. Then, the variable speed induction motor 1 starts rotating.

The acceleration of the speed change of the variable speed induction motor 1 is related to the rotational speed of the small motor 30, but it is set in advance depending on the type of load communicated to the variable speed induction motor ii. When the speed is controlled, the speed change speed of the variable speed induction motor 1 can be arbitrarily adjusted.

It is also possible to combine the variable speed induction motor 1 of the present invention with a conventionally known pole number converter, thereby expanding the speed range of the motor and making it possible to use it in a high efficiency range.

〔Effect of the invention〕

As explained above, according to the present invention, at least one stator out of a plurality of stators is concentric with a rotor formed of a plurality of rotor cores and a plurality of conductors. Since a drive device for rotating the variable speed induction motor is provided, and a rotation speed adjustment device for adjusting the rotation speed is connected to the drive device, the speed change speed of the variable speed induction motor can be changed from the start of operation to the time of stop. That is, since the acceleration of the load connected to the variable speed induction motor can be adjusted as desired, the speed change can be increased or decreased depending on the characteristics of the load. In particular, for loads that require adjustment of acceleration from a stopped state to gradually increase speed until reaching a predetermined speed, or adjustment of acceleration from a predetermined speed to a stopped state, for example, elevator 1 loading It has remarkable effects such as allowing the lateral movement of a machine lift to speed up, decelerate, and stop smoothly, resulting in high efficiency and preventing troubles such as cargo collapse.

[Brief explanation of the drawing]

Figures 1 to 11 show examples of the present invention, with Figure 1 being a side sectional view of an induction motor, and Figure 2 being a side sectional view showing a stator rotation mechanism and rotation position detection mechanism. , Fig. 3 is a diagram of an embodiment in which a pulse motor is used for the rotation mechanism and the rotation position is detected by a memory calculation circuit, Figs. 4 and 5 are wiring diagrams of the windings wound around both stators, and Fig. Figure 6 is a diagram showing the relationship between rotor slip and active power, Figure 7 is an electrical equivalent circuit diagram of the rotor, Figure 8 is an electrical equivalent circuit diagram seen from the stator side, and Figure 9 is a diagram of the stator. Diagram showing the relationship between speed and torque when windings are connected in series,
FIG. 10 is a diagram showing the relationship between speed and torque when the stator windings are connected in parallel to a power source, and FIG. 11 is a block diagram showing the configuration of automatic control. 1... Variable speed induction motor, 2, 3... Rotor core,
4... Rotor shaft, 5... Non-magnetic core, 6... Conductor, 7... Rotor, 8... Short circuit ring, 9... Connecting material, 10° 11... Side part, 12... Ventilation barrel, 13...
・Vent, 14...Machine frame, 15.16...Bearing board,
17...Connecting rod, 18...Nut, 19.20...
- Cooling impeller, 21... bearing, 22.23... winding, 24... first stator, 25... second stator, 26
... Sliding bearing, 27 ... Fixed ring, 28 ... Stop ring, 29 ... Gear, 30 ... Small motor, 31 ... Drive gear, 32 ... Ventilation port, 33 ...
... Ventilation port, 34... Ventilation port, 35... Ventilation port, 3
6... Exhaust fan, 37... Motor, 38... Space, 39... Magnetic body, 40, 40a, 40b, 4
0c, 40d... Rotation position detector, 41... Rotation position indicator, 42... Control device, 43... Solenoid, 44... Bearing, 45... Rotation shaft, 46 ...Worm gear, 47...Pulse motor-148...
Speed detector (49...speed indicator, 50...input/output circuit, 51...control circuit, 52...arithmetic circuit, 53
...Memory circuit, 54...Temperature detector, 55...Rotation speed setting device, 56...Keyboard.

Claims (3)

[Claims] (1) A plurality of conductors installed in each of a plurality of rotor cores are connected to form an integral rotor, and in an outer peripheral portion facing each of the plurality of rotor cores. , a plurality of stators are arranged in parallel on the machine frame, and each of the plurality of conductors is short-circuited between the plurality of rotor cores via a connecting member or a resistive material that conducts electricity when an arbitrary voltage is applied. In addition, at least one stator among the plurality of stators is provided with a drive device for rotating the stator concentrically with the rotor so as to be rotatable, and the drive device is configured to rotate the stator. A variable speed induction motor characterized by being provided with a rotational speed adjustment device for adjusting the speed. (2) The drive device eliminates a phase shift between a voltage induced in a rotor conductor facing a rotatable stator and a voltage induced in a rotor conductor facing another stator. °
The variable speed induction motor according to claim 1, wherein the variable speed induction motor is configured to be able to be arbitrarily set and maintained within a range of 180° from 180°. (3) The variable speed induction motor according to claim (1) or (2), wherein the drive device is formed by a pulse motor.