FI122140B - Electric motor to operate a transport system - Google Patents

Description

FIELD OF THE INVENTION FIELD OF THE INVENTION

The present invention relates to an electric motor according to the preamble of claim 1.

5 PRIOR ART

Electric motors in conveying systems traditionally have a rotor and a stator positioned relative to one another, with an air gap between them. The motor magnetic circuit between the stator and the rotor is shaped such that the magnetic flux forms a loop passing substantially perpendicularly across the air gap in opposite directions, whereby the magnetic flux curves in the rotor and stator. Both the rotor and the stator are therefore made of ferromagnetic material to control the magnetic flux. The magnetic flux through the air gap of the motor, i.e. the air gap, contains harmonics which induce eddy currents in the ferromagnetic material of the moving rotor, causing power loss and heating of the rotor. Particularly many harmonics 20 occur in motors having a stator with a central winding.

The variation in magnetic flux density causes local saturation of the rotor ferromagnetic material, which distorts the magnetic flux. The result is an increase in engine ^ 25 torque color, which weakens the transport system oo? its operating characteristics.

δ x Publication FI93633B discloses an elevator machine having an α-disk rotor and wherein the stator forms a ...

g around the rotor of the gas sector. The air gaps g of the two sides of the rotor 30 and are substantially perpendicular to the axis of sa ^.

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PURPOSE OF THE INVENTION

It is an object of the present invention to provide a compact and lightweight motor for a conveying system, in which the eddy current losses of the rotor, in particular, are reduced, especially when using centralized winding as a stator winding. In the motor of the invention, the rotor does not necessarily need any ferromagnetic material. It is also possible to make the rotor smaller inertia than in the known engines of the transport systems 10. Also, in the motor according to the invention, the momentum color is smaller than known.

SUMMARY OF THE INVENTION

The engine according to the invention is characterized in what is stated in the characterizing part of claim 1. Other embodiments of the invention are characterized in what is set forth in the other claims.

Inventive embodiments are also disclosed in the specification and drawings of this application. The inventive content contained in the application may also be defined otherwise than as set forth in the claims below.

The inventive content may also consist of several separate inventions, especially if the invention is considered in the light of the express or implied subtasks or the benefits or classes of benefits achieved. In this case, some of the attributes contained in the claims below may be unnecessary for the discrete ideas of the keko S '. The features of the various embodiments of the invention may be applied within the scope of the inventive basic idea to other embodiments.

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^ 30 connection.

The transport system referred to in the invention may be, for example, an elevator system, an escalator system, a walkway system, a crane system, a conveyor system comprising one or more conveyor belts, or a road or rail transport system.

One electric motor according to the invention for driving the conveying system has a disc-shaped rotor 5 made of non-ferromagnetic material and first and second stator disposed on opposite sides of the same rotor disk to form a common magnetic circuit between said first and second stator and rotor. Thus, the first air gap between the first stator and rotor and the second air gap between the second stator and rotor are substantially parallel to the axis of rotation of the rotor. By electric motor is meant an engine which can both convert electrical energy into mechanical energy of the transport system, such as motion or potential energy, and also convert mechanical energy of the transport system back into electric energy, for example in the case of so-called motor regeneration. Non-ferromagnetic material means material that does not contain ferromagnetic material. As shown in the invention, the rotor parts which form part of the motor magnetic circuit are made of non-ferromagnetic material, but instead of the fastening means and other non-magnetic parts, q can naturally also contain ferromagnetic material.

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In a method according to the invention for manufacturing an electric motor of a conveying system, a disk-like rotor is made of non-ferromagnetic material; fitting the first and second stator to opposite sides of the same rotor disk; forming a joint between the first ° g and the second stator and rotor

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the magnetic circuit; adjusting the first stator at a predetermined distance from the first side of the rotor to form a first air gap substantially parallel to the axis of rotation of the rotor; and positioning the second stator at a predetermined distance from one side of the rotor to form another air gap substantially parallel to the axis of rotation of the rotor.

One of the electric motors according to the invention has a centralized break-through coil.

In one of the motors according to the invention, the permanent fracture winding is a centralized double-layer winding.

In an electric motor according to the invention, the width of the groove base is constant with respect to the length of the groove, whereby the winding effectively fills the groove.

In an electric motor according to the invention, the winding of the rotor and / or the stator is a fractional constant winding having a constant number of 2/5.

In one embodiment of the invention, said electric motor is a permanent magnet synchronous machine.

The rotor according to the invention can be made, for example, of fiberglass laminate, stainless steel or plastic.

In an elevator system, an electric motor according to the invention is arranged vertically in the elevator shaft close to the wall so that the axis of rotation is substantially ab c? horizontally, but the machinery may also be located elsewhere in the elevator shaft or it may also be located in the engine room, g Further, the electric motor according to the invention may be used in both counterweighted and counterweighted hoop systems.

In one embodiment of the invention, the drive motor drive wheel 30 is integrated with the rotor, and the combination of the rotor and drive wheel is adapted to rotate relative to a stationary shaft by means of a bearing arrangement. In another embodiment of the invention, the drive wheel and rotor are mounted on a shaft and the shaft is adapted to rotate through bearings 5 relative to the stator body.

ADVANTAGES OF THE INVENTION

Among other things, the invention provides at least one of the following advantages:

According to the invention, the rotor can be made of a non-ferromagnetic material, such as composite material, whereby the rotor becomes light and the rotor inert. Hereby, the kinetic energy bound to the inertia of the rotor is reduced, which is advantageous in transport systems. 15 - When the rotor forms a common magnetic circuit with stators disposed on opposite sides of the rotor, the magnetic flux passes substantially linearly through the rotor. In this case, the magnetic flux need not be rotated in the rotor, and the rotor need does not comprise ferromagnetic material controlling the magnetic flux. Thus, it is possible to make the rotor from a non-ferromagnetic material. Because the magnetic flux through the air gap of the engine always contains some

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^ 25 harmonics, and harmonics cause vortex currents in the ferromagnetic material, such a non-ferromagnetic material x dl rotor has no eddy current and produces a reduction in rotor power losses, an increase in motor efficiency and a rotor heating. Particularly o ...

a great advantage is achieved if the stator winding is made into a central winding, since the airflow provided by the central winding differs 6 strongly from the sinusoidal one, and the airflow harmonics thus cause considerable power losses in a ferromagnetic material rotor. On the other hand, when the central winding is used, the coil ends of the motor are considerably shortened, so that the motor according to the invention can be made at the same time not only low in power, but also small and light. In addition, as rotor losses are reduced, rotor ventilation can be reduced, which saves space and costs.

Since there is always some local saturation in a rotor made of ferromagnetic material such as dyna-plate, where the magnetic flux density is high, the permeability of the magnetic circuit in the ferromagnetic material rotor varies. This saturation permeation variation causes torque to the engine, which is reflected in the loss of driving comfort of the transport system. When the rotor is made of non-ferromagnetic material as disclosed in the invention, such permeation variation in the rotor does not occur, thereby reducing the torque of the motor and improving the ride comfort of the transport system. In this case, the motor noise is also quieter.

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00? By making the motor axial-flow motor such that the first and second air gaps are substantially parallel to the axis of rotation of the rotor, it is possible to make the motor flat and disc-shaped, which makes it easier to fit the motor into the conveying system.

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When rotor magnetization is performed with permanent magnets such that the rotor is made of a bonding matrix, for example, of a composite material, and the permanent magnets are attached to the bonding matrix, the 5 rotors become rigid and durable. Such an attachment matrix also provides the magnetic material with protection against corrosion. Thereby, it is also possible to fabricate the rotor such that the permanent magnets are enclosed within the mounting matrix, thereby improving the corrosion resistance.

It is possible to make the motor according to the invention in a completely enclosed structure, whereby the protection of the motor against, for example, dirt and moisture and, for example, ferromagnetic iron dust, is improved.

If the engine according to the invention is fitted to the elevator system, the drive wheel of the elevator can be mounted on the motor shaft, or the drive wheel can also be integrated as an integral part of the rotor.

According to the invention, the stator grooves may have open-to-20-meter grooves, whereby the central winding can be fitted to the stator through open grooves, which speeds up and simplifies the manufacture of the stator. The stator windings can also be closed in the grooves by groove closures, such as groove wedges. These groove wedges ^ 25 can also be made of ferromagnetic material.

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o o - the first and second stator windings arranged on either side of the rotor can be connected in parallel,

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whereby the parallel stator windings can be controlled by a single power control apparatus, such as o ...

o with the drive. On the other hand, the static windings C \ l ...

may also include interfaces to separate power control systems, whereby the windings may be controlled, for example, by separate inverters. In this case, if one of the stator windings or the inverters fails, the defective stator / inverter can be isolated and the motor 5 can be driven with limited torque by a still operating stator, thereby improving the reliability of the conveying system.

According to one embodiment of the invention, it is also possible to accommodate a plurality of rotor and two stator assemblies on both sides of the rotor on the same motor rotation axis, whereby the dimensioning of the motor can be increased.

LIST OF FIGURES

In the following, the invention will be described in more detail with reference to the accompanying drawings, in which: Figure 1 shows a rotor disk of an engine according to the invention and stator disposed on opposite sides of a rotor disk; fitted central winding δ ^ Fig. 4 shows an elevator motor according to the invention oo o ^ Fig. 5 shows another elevator x 25 motor according to the invention cc

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Fig. 6 shows a third hoop engine according to the invention.

Fig. 7 shows a power supply arrangement 9 for parallel stators of an engine of the invention

Fig. 8 shows a power supply arrangement in which the stator of the motor according to the invention is powered by separate frequency converters

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows a schematic view of how the rotor 2 and the two stators 3,4 in the motor 1 according to the invention are arranged relative to each other. The rotor 2 is made of a non-ferromagnetic material, which here is a composite, as a fixing matrix, and the permanent magnets 10 10 are enclosed within the fixing matrix. The permanent magnets are arranged one after the other on the same circumference such that the polarities of two consecutive magnets are in opposite directions. The direction of the magnitude vector of the magnetic field formed by the permanent magnets is substantially parallel to the rotation axis 8 of the rotor. The first stator 3 and the second stator 4 are arranged on opposite sides of the same rotor disk 2 to form a common magnetic circuit 5 between said first and second stator and rotor. In the motor, the first stator 20 3 and the second stator 4 are disposed on a air spaces 6.7 are formed which are substantially parallel to the rotation axis 8 of the rotor.

Fig. 2 shows a part of the magnetic circuit of the motor ab according to the invention in a straight line. Here, a central winding is fitted to the first 3 and i to the second 4 stators, o x Fig. 2 illustrates the flow of the magnetic flux in the magnetic circuit 5 of the motor at one point in time. The directions of the instantaneous current of the stator windings are then o ....

g is marked in the figure so that the cross (X) represents the current flow o CVJ towards the pattern and the dot (.) represents the flow away from the pattern. The magnetic flux is closed as a loop in the magnetic circuit 5 passing from the tooth of the first stator 3 through the first air gap 6 to the rotor 2, and from the rotor through the second air gap 7 to the tooth of the second stator 4. The magnetic flux curves at the second stator 4 at the stator back 5 and returns to the first stator 3 where the magnetic flux curves again. Because the magnetic flux passes substantially directly through the rotor in opposite directions, the rotor can be made of non-ferromagnetic material. Instead, the stator 3,4 is made of ferromag-10, as the magnetic flux curvature in the stator is controlled by ferromagnetic material. Since the rotating rotor 2 is of non-ferromagnetic material, the airflow harmonics caused by the central stator windings do not induce vortex currents in the rotor 15, thereby reducing power losses and thereby the rotor heating.

Figure 2 also illustrates an example of how the windings are closed in the grooves by closing the open groove openings with the groove closures 13, which are here groove wedges.

Figure 3 shows a stator 3,4 according to the invention fitted with a centralized double-layered winding 11. The motor stage belt 18 is then arranged around the tooth in adjacent grooves such that the phase current forms a loop around the tooth. In such a centered 25-layer winding, the rib ends 17 remain cold, which reduces the size and weight of the motor.

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Fig. 4 shows an elevator engine according to the invention. The elevator motor has a traction sheave 9 which is fixedly fixed to the rotor 2. The rotation axis · g 30 li 8 of the rotor is also marked in the figure. A stator 3,4 is disposed on either side of the disk-like rotor 2 o g, and this assembly of rotor 2 and two stators 3,4 is made into a closed structure 2,3,4.

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Fig. 5 shows another elevator motor according to the invention. Here, sets of rotor 2 are arranged on either side of the drive wheel 9 and two stator 3,4s arranged on both sides of the rotor.

Figure 6 shows a third elevator motor according to the invention. Here, two sets of rotors 2 and two stator 3,4s arranged on either side of the rotor are arranged side by side on the same axis of rotation 8.

Figure 7 shows an engine power supply arrangement in which the first and second stator windings are connected in parallel. In this case, the parallel stator windings are fed by a single frequency converter 14 connected between the mains 19 and the stator windings parallel to the first 3 and the second 4 15 stator.

Figure 8 illustrates a power supply arrangement in which power is provided to the first 3 and the second 4 stator of the motor of the invention by separate frequency converters 14,15. The inputs of both inverters are then connected to the mains 19. The output of the first frequency converter 14 is connected to the stator winding terminal of the first stator 3 and the output of the second frequency converter 15 is connected to the static winding terminal 25 of the second stator. In this case, the frequency converters ab control the stator windings separately by supplying alternating amplitude and frequency alternating voltage to the static o x windings.

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It will be apparent to one skilled in the art that the invention is not limited to the foregoing embodiments wherein

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o the work is described by way of example, but many

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and various embodiments of the invention are possible within the scope of the inventive idea defined in the claims set forth below.

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Claims (7)

Elevator motor (1) having a central breakage winding 5 in the elevator motor stator (3, 4) and magnetized by permanent magnets (10) in the elevator motor rotor (2), characterized in that the disc motor rotor (2) of the elevator motor is manufactured ferromagnetic composite material to a bonding matrix to which the permanent magnets (10) are fixed and that the elevator motor has a drive wheel (9) which is fixedly connected to said rotor (2), either attached to the rotor or integrated with the rotor (15); and the second (4) stator is arranged on opposite sides of the same rotor disk (2) to form a common magnetic circuit (5) between said first and second stator and rotor and that first air gap (6) between the first stator (3) and rotor (2) and the second air gap (7) between the second stator (4) and the rotor (2) being substantially the axis of rotation of the rotor n (8). ς Elevator motor according to claim 1, characterized by cvj. . .., 25 that the permanent magnets (10) are a closed fastener? inside the rice. δ Elevator motor according to one of the preceding claims, characterized in that the first (3) and second (4) stator have a central winding (11). o o g 30 Elevator motor according to one of the preceding claims, characterized in that the first (3) and the second (4) stator have open slots (12) and that the first and second stator are fitted with a central winding (11). ) through open slots. 5. Hissmotor enligt nägot av de föregäende patentkraven, kännetecknad av, att lindningarna inneslutits i spären 5 genom att spärmynningarna tillslutits med spärförslutningar (13). Elevator motor according to one of the preceding claims, characterized in that the windings are closed in 5 grooves by closing the open grooves in the grooves (13). 6. Hissmotor enligt nägot av de föregäende patentkraven, kännetecknad av, att den första och den andra statorlindningen är parallellkopplade. Elevator motor according to one of the preceding claims, characterized in that the first and second stator windings are connected in parallel. Elevator motor according to one of the preceding claims, characterized in that the first stator winding (3) comprises a connection to the first power control device (14) and the second stator winding (4) comprises a connection to the second power control device 15). 1. Hissmotor (1), hissmotors stator (3, 4), and hissmotors rotor (2), magnetiser av permanentmagneter (10) , cantilevers av: att hissmotorns with rondellform rotor (2) and rotating nets icke-ferromagnetiskt compositmaterial till en fästmatris 10 i flashing a permanent magnet (10), att hissmotorn försedd med en drivskiva (9) som är fast förbunden och antingen första i rotorn eller första integrerad i rotorn, att hissmotorns första (3) och andra (4) stator för 15 belägna nap motatsatta sidor av rotorskivan (2) första en gemensam magnetkrets (5) bildas av den första och den andra statorn och rotorn, och att det första luftgapet (6) mellan den första statorn (3) och rotorn (2) och det andra luftgapet (7) 20 mellan den andra statorn (4) och rotorn (2) väsentligen har samma riktning som rotorns rotationsaxel ( 8). Hissmotor enligt patent krav 1, a rotary encoder, a permanent magnet (10) and an inertial matrix. 03 cp. 't co § 4. Hissmotor enligt face av de föregaende patentkraven, GO o kännetecknad av, att den första (3) och den andra (4) ^ statorn har öppna sparmynningar (12) och att den concentrerade lindningen (11) monterats i den första och den andra statorn via spärmynningarna. 7. Hissmotor enligt visgot av de föregäende patentkraven, kännetecknad av, att den första statorlidningen (3) omfattar en anslutning account en (14) och den andra statorlidningen (4) omfattar en anslutning account en andra 15 effektstyr. δ CVJ 00 o δ X cc CL 00 o o 00 o o CM