FI119960B - Electric Machine Rotor Hub Module and Electric Machine Rotor - Google Patents

Description

ELECTRICAL MACHINE SWITCH MODULE AND ELECTRICAL MACHINE SWITCH

The invention relates to an electric machine rotor hub module according to claim 1 and to an electric machine rotor according to claim 8.

In permanent magnet synchronous machines, a magnetization field is created with permanent magnets mounted on the rotor of the machine. The permanent magnets are placed either on the air-side face of the rotor or the permanent magnets are embedded in the magnetic core of the rotor. Magnetic cores are mostly made of ferromagnetic iron plates assembled with rotor-length plate packages. The design of permanent magnets and plate packages is based on the magnetization power required by the electrical machine. The mechanical structure and the attachment of the various parts are affected, among other things, by the forces acting on them and the size of the electrical machine.

In electrical machines with a large number of poles and a large rotor diameter, especially low-voltage machines with a centralized winding of the stator, special requirements are imposed on tracking magnetization. In these machines, the constant number q is <1 when the constant number is defined as q = Q / (m * 2 * p), where Q represents the master number of the machine, m is the phase number of the machine and p is the number of poles of the machine. Centralized winding is understood to mean a stator winding in which a coil of winding is wound around one tooth of a stator. Due to the high number of poles, there is a small space per magnet pole in the circumferential direction of the rotor. The radial path of the magnetic flux is narrow. The use of the above-mentioned surface magnet is often not possible because the surface magnets do not provide sufficient magnetic flux density for heavily loaded applications.

Reliable attachment of permanent magnets and magnetic cores must be arranged in such a way that the flow of the magnetic flux is not disturbed. The good efficiency of a permanent magnet electrical machine also requires that the stray flux be as small as possible. The handling of large-diameter magnetic cores during the manufacture of an electrical machine is difficult, and consequently the manufacturing and manufacturing technology must be planned in advance so that the parts of the machine can be manufactured in advance in smaller and easier-to-handle parts.

It is an object of the present invention to provide an efficient and affordable rotor hub structure for a large diameter electrical machine. To accomplish this, the pole module according to the invention is known from the features of the characterizing part of claim 1. The rotor of the invention 30 is known from the features of the characterizing part of claim 8.

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Other preferred embodiments of the invention are known from the features of the dependent claims.

In the solution of the invention, the rotor hub structure of an electrical machine is formed by a plurality of hub modules which are mounted in a circumferential direction successively to the outer rotor pin 5 of the rotor. Magnetic plate packages for pole modules can be manufactured separately. This makes them easier to handle and can be done individually until finished. The number of parts to be mounted on the rotor center and the number of bores made in the rotor center are substantially reduced by the solution according to the invention. The assembly time of the rotor and the assembly time at the factory are also significantly reduced. The solution also facilitates the automation of manufacturing and co-10 assembly.

The solution according to the invention simplifies and substantially simplifies the manufacture of the frame structure when the frame structure is extruded from aluminum and does not require machining. Furthermore, the structure according to the invention minimizes diffusion between the poles, whereby the efficiency of the machine is improved.

With the rotor of the invention, the core part of the rotor magnetic circuit is formed by modules mounted on the outer periphery of the rotor, wherein at least two permanent magnets can be fitted to each module and the module forms two poles, and The manufacturing time of the rotor is accelerated and, in particular, the assembly time at the factory is reduced when the finished hub modules 20 can be mounted on the rotor center.

According to a preferred embodiment of the invention, the hub module is four rotor hub wide. The frame structure modules can thus be fixed to the rotor center at even intervals in the circumferential direction, with the fixing screws below each other permanent magnet.

According to a preferred embodiment, the hub module can be attached to its rotor center from its housing 25 between the plate packages. The body can then be secured without permanent magnets, which can be retrofitted, for example, in the radial direction of the rotor, and lockable in place by a mounting strip that fits into the grooves in the plate packages During installation, the permanent magnets may On the other hand, pre-magnetized permanent magnets can also be used within the scope of the invention. The mounting mounts on the permanent magnets not only support the permanent magnets against centrifugal forces, but also protect the permanent magnets from dirt and corrosion.

According to a preferred feature of the invention, the panel package and the body member are locked together by a form locking joint. Useful and functional joints are, in particular, a salmon-5 tail joint or a T-groove joint, of which there are many examples in the prior art. In the context of the present invention, they allow for a functional and practical configuration as well as a flexible variation in configuration. The plate package can be fitted in whole or in shorter portions to the body or even plate at a time.

According to a further preferred feature, the non-magnetic body is made of aluminum. The Alu-10 mine is useful as a base material for its electrical, magnetic and strength properties. Extruding aluminum makes it easy and inexpensive to produce a sufficiently precise piece.

According to a preferred embodiment, the rotor center is non-magnetic and electrically conductive, whereby the rotor center acts as a damping coil, damping the pulsating leakage 15 thereby reducing the resulting losses. Due to their thermal conductivity, the aluminum housing also contributes to the cooling of the rotor.

The invention will now be described in detail with reference to the drawings, in which: - Figure 1 shows a hub module according to the invention, - Figure 2 shows a hub module according to the invention mounted on a rotor and - Figure 3 shows another hub module according to the invention mounted on a rotor.

Figure 1 shows a pole module according to the invention, viewed from the end of the module. The module has a width of three magnetic poles in the circumferential direction of the rotor and has an aluminum extruded body structure 2. The module has a rotor length along the axis of the machine. The inner surface 4 of the frame structure is slightly curved corresponding to the cylindrical outer surface of the rotor center. In the circumferential direction of the rotor there is a mounting groove 3 at one end of the frame structure 2 and a corresponding mounting projection 5 at the other end. The outer surface of the module body has salmon-shaped projections or dowels 6 at each magnetic pole 8. The corresponding notch 12 of the salmon tail connection is formed at the bottom edge of a plate pack 10 formed of magnetically conductive plates. The plate packages 10 form the magnetic rotor core of the rotor. The rotor cores are magnetized with permanent magnets inserted between them to form alternately the N and S-5 poles of the rotor. Their upper edge forms the outer surface of the rotor facing the air gap of the electrical machine. Preferably, the side walls 14 of the board packages are slightly inclined so that a rectangular space 15 is provided between adjacent board packages for a permanent magnet. In the outermost part of the side walls 14 of the board packages, narrow fastening grooves 16 are formed into which the fastening strips 20 (Fig. 2) of the permanent magnets 18 are inserted after the permanent magnets 10 have been inserted. The rotor core is drilled with holes 22 in which the rotor core plates 24 are pressed together by means of threaded tongs 24 by means of the hub end plates 26.

Figure 2 illustrates the hub module 30 attached to the rotor center 28. The hub module 30 has four hubs, but otherwise corresponds to the module of Figure 1, and indeed the corresponding parts are numbered with the same reference numerals in Figures 1 and 2.

In the manufacture of the rotor, the plate packages 10 forming the core of the rotor are attached to the body structure of the hub module by means of a dovetail connection. The plates of the plate packages are made, for example, by cutting them to the correct shape. The disc packages are clamped tightly together by end plates 26 and threaded rods 24 passing through the disc packages. The body portion 2 'of each hub module is secured to the rotor center 28 ke-20 by two bolts 32 in the direction thereof which are fitted to the holes 34 between the hub cores. The number of fastening bolts 32 is dependent on the length of the rotor. The curvature of the base 31 of the hub module body portion 2 'corresponds to the curvature of the outer peripheral surface of the rotor center 28. The bolts 32 are fitted to the two extreme openings for the permanent magnets 18 of the hub module. On one side of the hub module is a rotor ke-25 rotary mounting slot 38 and on the other side a corresponding mounting projection 40 for positioning and supporting the hub ducts relative to one another. In place of the fixed pole module, permanent magnets 18 are placed in the radial direction of the rotor between the plate packages 10. Thus, some of the permanent magnets are between the disk packages of one pole module and some between the extreme disk packages of two adjacent pole modules. The permanent magnets are glued to the pole-30 duel and placed on the air-side side of the permanent magnets with a mounting strip 20 in the mounting grooves 16 formed therefor. The mounting strips support the permanent magnets against centrifugal forces and protect the permanent magnets against corrosion and other environmental influences.

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It is also an idea of the invention to assemble the hub modules directly on the surface of the rotor center, whereby the body part is first fixed to the rotor center and then the plate packages and further the permanent magnets are fitted. The body parts can then also be fastened to the plate package.

Fig. 3 shows an embodiment of the invention in which the attachment of the plate packages and the body part differs from the embodiment of Fig. 2. The reference numerals of Figure 3 correspond, where applicable, to the numbering used previously, the body 42 having a T-shaped peg 44 and a corresponding T-shaped groove 46 in the board package 43, provided with clamps 48 supporting the center magnets 10 of the permanent magnets. against. In this embodiment, the permanent magnets 18 are mounted in the axial direction of the rotor either in the openings between the plate packages or simultaneously with the plate packages 43. For corrosion protection, the outer surface 45 of the permanent magnets is coated with, for example, varnish or resin. The body portion 42 is secured by screws 50 extending through the rotor center 52, which are tightened inside the rotor center 52.

The embodiments shown in Figures 2 and 3 may also be combined where appropriate to realize the idea of the invention. The attachment between the plate package and the frame part can also be made by means of end plates, whereby the end plates are also bolted to the ends of the frame part. The junction of adjacent body members may also be, for example, curved or fully or partially inclined in the position described above.

The number of poles in the rotor according to the invention is large, at least more than ten. The solution of the invention effectively implements rotors having a number of poles of several dozen or more than one hundred. In electric machines with centralized winding, the winding layer being wound around one tooth, the rotor according to the invention is particularly useful.

The invention has been described above with reference to some embodiments thereof. However, the disclosure is not to be construed as limiting the scope of the patent, but the various embodiments may vary within the limits set forth in the following claims. For example, the hub module body may extend circumferentially at the boundary of the disk package and the permanent magnet. When the na module is assembled directly to the rotor center, the junction of the body members may also be at the plate package.

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Reference numerals: 2, 2 'frame structure; 3 mounting slots; 4 inner surface of the frame structure; 5 asen brackets; 6 salmon tail dressing; 8 magnetic poles; 10 disc packages; 12 salmon tailed fish; 14 5 side panel wall panel; 15 space for permanent magnet; 16 mounting grooves; 18 permanent magnets: 20 mounting mounts; 22 hole; 24 threaded rod; 26 end plate; 28 rotor center; 30 pole module; 31 base of base; 32 fixing bolts; 34 hole; 38 mounting slots; 40 mounting bracket; 42 body; 44 T-shirt; 45 outer surface of permanent magnet; 46 T-groove; 48 coatings; 50 screws; 52 rotor center 10

Claims (11)

A pole module (30) for an electric motor rotor, characterized in that it comprises an non-magnetic body part (2,2 ') which is at least as wide as two rotor poles (8) and at least two in the body part (2,2') plate pack (10) forming at least two of the rotor poles (8), wherein on the pole module (30) between two adjacent plate pack a space (15) into which a permanent magnet piece (18) can be fitted. 2. A pole module according to claim 1, characterized in that the pole module (30) is as wide as four rotor poles (8). 3. A pole module according to claim 1, characterized in that the pole module (30) can be fixed in its body part (2.2 ') between the plate packages in the rotor center (28). A pole module according to claim 3, characterized in that the permanent magnets (18) can be mounted on the pole module (30) in the radial direction of the rotor after attaching the pole module (30) and read in place with fastening strips (20). 5. A rotor according to any of the preceding claims, characterized in that the plate package 15 (10) and the body part (2,2 ') are fastened to each other with a mold-reading joint (6,12). 6. A rotor according to claim 5, characterized in that the plate package and the body part are connected to each other with a salmon-tailed ball joint (6,12) or a T-lock ball joint (44,46). 7. A rotor according to any of the preceding claims, characterized in that the non-magnetic body part (2,2 ') consists of aluminum. 8. A rotary magnetized electric motor rotor, the magnetic circuit of which comprises a core part formed by magnetically conductive plate pack (10), in which the permanent magnets (18) are fitted and the electric motor pole number is large, characterized in that the core part is formed by modules (30). which are fitted in the periphery of the rotor, wherein in each module (30) can be fitted at least two permanent magnets (18) which are fitted between the plate packages, and that the module forms the corresponding at least two poles (8) and that the pole modules (30) can be fixed in the rotor center (28). 9. A rotor according to claim 8, characterized in that the pole modules (30) comprise a plate package (10) and a non-magnetic body part (2,2 ') mounted in the plate package. 10. A rotor according to claim 9, characterized in that the non-magnetic body part (2,2 ') is electrically conductive and heat conducting. 11. A rotor according to any one of claims 8-10, characterized in that the pole modules (30) comprise openings (15) directed towards the outer surface of the rotor (15) for permanent magnets 5 (18), and that the openings (15) can be closed with fastening strips (20). ).