Device and method for impregnating stator of electric machine

Abstract

The invention relates to a device for impregnating a stator (50) of an electric machine, comprising: a container (30) for accommodating at least one stator (50) to be impregnated, the container (30) being configured for accommodating a liquid impregnating agent; a plurality of input terminals (14, 15, 16) for connecting input conductors (54, 55, 56) of a winding of a stator (50) to be impregnated and a plurality of output terminals (41, 42, 43) for connecting output conductors (51, 22, 53) of a winding of a stator (50) to be impregnated. The invention also relates to a method for impregnating a stator (50) of an electric machine with a device according to the invention.

Description

Technical Field

[0001] The present invention relates to an apparatus and a method for impregnating the stator of an electric machine with a liquid impregnating agent. Background Art

[0002] An electric machine having a stator is known from DE 10 2023 000 728 A1. The stator includes a plurality of stator windings. The connection wires of the stator windings extend from the winding heads of the stator windings. The electric machine further includes a rotor that is rotatable relative to the stator about a rotational axis.

[0003] The windings of the stator must be mechanically and electrically strengthened and be resistant to chemical and electrical influences. For this purpose, it is known to apply a liquid impregnating agent, such as a resin or a resin curing agent mixture, to the windings and then cure it. For applying the impregnating agent, it is known to sprinkle the windings with the impregnating agent or immerse the windings in the impregnating agent. Summary of the Invention

[0004] Accordingly, an object of the present invention is to improve the apparatus and method for impregnating the stator of an electric machine.

[0005] This object is achieved by an apparatus for impregnating the stator of an electric machine having the features given in claim 1. Advantageous designs and improvements are the subject of the dependent claims. This object is also achieved by a method for impregnating the stator of an electric machine having the features given in claim 10.

[0006] The apparatus for impregnating the stator of an electric machine according to the present invention includes a container for receiving at least one stator to be impregnated, the container being configured to receive a liquid impregnating agent. The apparatus further includes a plurality of input terminals - in particular exactly three input terminals - for connecting the input wires of the windings of the stator to be impregnated. The apparatus further includes a plurality of output terminals - in particular exactly three output terminals - for connecting the output wires of the windings of the stator to be impregnated.

[0007] The input terminals and the output terminals enable the connection of the windings of the stator to be impregnated to a power source. The power source connected to the windings can cause current to flow through the windings, thereby heating the stator. At an elevated temperature, the viscosity of the impregnating agent decreases and the impregnating agent flows around the stator windings. Thus, with the apparatus according to the present invention, impregnation of the stator can be achieved relatively easily, at low cost, and in a short time.

[0008] According to a preferred design of the present invention, the container is configured in a cuboid shape and has a bottom plate, a first side wall, a second side wall, a first end wall, and a second end wall. Here, the side walls are opposite each other and the end walls are opposite each other. Thus, the container has a relatively simple structure.

[0009] According to a preferred design of the present invention, the device includes a terminal group having output terminals. The output terminals of the terminal group are electrically connected to each other. Thus, a star point is formed by the connection portions of the output wires of the windings of the stator to be impregnated.

[0010] According to a preferred design of the present invention, the device includes a plurality of terminal units, each of which contains one of the input terminals. Here, the input terminals of the terminal units are electrically isolated from each other. Thus, a polyphase power supply can be connected.

[0011] According to a preferred design of the present invention, the terminal units each have a contact for connecting to a power supply. Here, the contacts of the terminal units are electrically connected to the input terminals of the terminal units respectively.

[0012] According to a preferred design of the present invention, the device includes a power supply - in particular a three-phase power supply - having a plurality of feed lines - in particular exactly three feed lines. Each feed line is electrically connected to one of the contacts respectively. The power supply connected to the contacts enables current to flow through the windings, thereby heating the stator.

[0013] According to a preferred design of the present invention, the terminal units are fixed to the wall of the container. The terminal units pass through the wall of the container, and the input terminals are respectively arranged on the side of the wall opposite to the contacts. Thus, the power supply can be connected to the contacts outside the container.

[0014] According to a preferred design of the present invention, the container includes a drain port for discharging the liquid impregnating agent. Thus, after impregnation and before removing the stator from the container, the excess impregnating agent can be drained from the container.

[0015] According to a preferred design of the present invention, the device includes a storage tank for storing the liquid impregnating agent. The storage tank is hydraulically connected to the container such that the impregnating agent can be transported from the storage tank to the container and from the container to the storage tank. Thus, the impregnating agent can be introduced into the container in a simple manner before the start of impregnation, and the excess impregnating agent can be drained from the container in a simple manner after impregnation and before removing the stator from the container.

[0016] The method according to the present invention for impregnating the stator of an electric motor using the device according to the present invention includes the following steps:

[0017] Placing the stator to be impregnated into the container;

[0018] Connecting the windings of the stator to a power supply;

[0019] Heating the stator by passing current through the windings during a preheating period;

[0020] Injecting the impregnating agent into the container;

[0021] Keep the stator in the impregnating agent while passing additional current through the winding during the impregnation duration;

[0022] Drain the excess impregnating agent from the container;

[0023] Harden the impregnating agent located on the winding while passing additional current through the winding during the hardening duration;

[0024] Disconnect the winding of the stator from the power supply;

[0025] Remove the impregnated stator from the container.

[0026] Using the method according to the present invention, the stator of an electric machine can be impregnated relatively simply and at low cost in a short time.

[0027] Before placing the stator to be impregnated into the container, the feeder lines of the power supply have been electrically connected to a contact respectively. After placing the stator into the container, the input leads of the winding of the stator are connected to the input terminals respectively. Similarly, the output leads of the winding of the stator are connected to the output terminals respectively. In this way, the stator winding is connected to the power supply.

[0028] After turning on the power supply, the current of each phase of the power supply flows through one of the windings respectively and reaches the star point of the stator. Adjust the flowing current so that the stator is heated to a temperature of about 130 °C during the preheating duration. The preheating duration is, for example, between ten minutes and twenty minutes.

[0029] Then, fill the impregnating agent into the container until the stator is covered by the impregnating agent. Keep the stator in the impregnating agent while passing additional current through the winding during the impregnation duration. The impregnation duration is, for example, 5 minutes.

[0030] After the impregnation duration ends, drain the excess impregnating agent from the container. The duration for draining the impregnating agent is, for example, 10 minutes. Then adjust the flowing current so that the stator is heated to a temperature of about 160 °C during the hardening duration. The hardening duration is, for example, twenty-five minutes.

[0031] Then turn off the power supply. Disconnect the input leads of the stator winding from the input terminals. Similarly, disconnect the output leads of the stator winding from the output terminals. In this way, the stator winding is disconnected from the power supply.

[0032] For example, in order to cool, keep the impregnated stator in the container for a duration. Then take out the impregnated stator from the container.

[0033] Further advantages are given by the dependent claims. The invention is not limited to the feature combinations of the claims. For a person skilled in the art, in particular from the purpose posed and / or by comparison with the prior art, other reasonable combination possibilities of the claims and / or individual claim features and / or features of the description and / or features of the drawings can be obtained. Description of the Drawings

[0034] The invention will now be described in detail with reference to the drawings. The invention is not limited to the embodiments shown in the drawings. The drawings only schematically show the subject matter of the invention. Among them:

[0035] Figure 1 shows a device for impregnating a stator,

[0036] Figure 2 shows an enlarged view of a terminal group,

[0037] Figure 3 shows an enlarged view of a terminal unit.

[0038] List of Reference Signs:

[0039] 11 First terminal unit

[0040] 12 Second terminal unit

[0041] 13 Third terminal unit

[0042] 14 First input terminal

[0043] 15 Second input terminal

[0044] 16 Third input terminal

[0045] 17 First contact

[0046] 18 Second contact

[0047] 19 Third contact

[0048] 30 Container

[0049] 31 Bottom plate

[0050] 33 First side wall

[0051] 34 Second side wall

[0052] 35 First end wall

[0053] 36 Second end wall

[0054] 40 Terminal group

[0055] 41 First output terminal

[0056] 42 Second output terminal

[0057] 43 Third output terminal

[0058] 50 Stator

[0059] 51 First output wire

[0060] 52 Second output wire

[0061] 53 Third output wire

[0062] 54 First input wire

[0063] 55 Second input wire

[0064] 56 Third input wire Detailed implementation manner

[0065] Figure 1 An apparatus for impregnating a stator 50 of an electric machine is shown. The apparatus includes a container 30 for receiving the stator 50 to be impregnated. The stator 50 is located in the container 30. The container 30 is also designed to receive a liquid impregnating agent (not shown here).

[0066] The container 30 is configured in a cuboid shape. The container 30 has a bottom plate 31, a first side wall 33, a second side wall 34, a first end wall 35 and a second end wall 36. The side walls 33, 34 are opposed to each other, and the end walls 35, 36 are opposed to each other. The bottom plate 31, the side walls 33, 34 and the end walls 35, 36 enclose a pool-shaped receiving area inside the container 30 for receiving the stator 50 and the impregnating agent. The lid side opposite to the bottom plate 31 is open.

[0067] Currently, the stator 50 has a first winding, a second winding and a third winding. The windings are wound with conductive metal wires. For example, the metal wires are coated with an insulating paint layer. Each winding has input wires 54, 55, 56 and output wires 51, 22, 53. The windings are arranged concentrically about the central axis of the stator 50.

[0068] The apparatus includes a terminal group 40. The output wires 51, 22, 53 of the windings of the stator 50 are electrically connected to the terminal group 40. The terminal group 40 electrically forms the star point of the stator 50.

[0069] The apparatus includes a first terminal unit 11, a second terminal unit 12 and a third terminal unit 13. The first terminal unit 11 has a first contact 17. The second terminal unit 12 has a second contact 18. The third terminal unit 13 has a third contact 19.

[0070] The terminal units 11, 12, 13 are fixed to the first side wall 33 of the container 30. The terminal units 11, 12, 13 pass through the first side wall 33 of the container 30. The contacts 17, 18, 19 are arranged outside the accommodation area of the container 30.

[0071] The device includes a three-phase power supply (not shown here). The power supply has three feeder lines. Each feeder line is electrically connected to one of the contacts 17, 18, 19 respectively. The terminal units 11, 12, 13 are electrically connected to an input wire 54, 55, 56 respectively.

[0072] The device includes a storage tank for storing a liquid impregnating agent. Here, the storage tank is hydraulically connected to the container 30 such that the impregnating agent can be conveyed from the storage tank to the container 30 and can be conveyed from the container 30 to the storage tank. For this purpose, the device includes, for example, a pump. Alternatively or additionally, the container 30 includes a drain port for discharging the liquid impregnating agent.

[0073] Figure 2 There is shown Figure 1 An enlarged view of the terminal group 40 of the device shown. The terminal group 40 has a first output terminal 41, a second output terminal 42 and a third output terminal 43. Thus, the device includes three output terminals 41, 42, 43 for connecting the output wires 51, 22, 53 of the stator 50 to be impregnated.

[0074] The first output wire 51 of the stator 50 is connected to the first output terminal 41. The second output wire 52 of the stator 50 is connected to the second output terminal 42. The third output wire 53 of the stator 50 is connected to the third output terminal 43.

[0075] The output terminals 41, 42, 43 of the terminal group 40 are electrically connected to each other. Thus, the output wires 51, 22, 53 of the stator 50 are also electrically connected to each other. Thus, the terminal group 40 electrically forms the star point of the stator 50.

[0076] Figure 3 There is shown Figure 1 An enlarged view of the terminal units 11, 12, 13 of the device shown. The first terminal unit 11 has a first input terminal 14. The second terminal unit 12 has a second input terminal 15. The third terminal unit 13 has a third input terminal 16. Thus, the device includes three input terminals 14, 15, 16 for connecting the input wires 54, 55, 56 of the stator 50 to be impregnated.

[0077] The first input wire 54 of the stator 50 is connected to the first input terminal 14. The second input wire 55 of the stator 50 is connected to the second input terminal 15. The third input wire 56 of the stator 50 is connected to the third input terminal 16.

[0078] The first contact 17 is electrically connected to the first input terminal 14. The second contact 18 is electrically connected to the second input terminal 15. The third contact 19 is electrically connected to the third input terminal 16. The input terminals 14, 15, 16 of the terminal units 11, 12, 13 are electrically isolated from each other. Therefore, the contacts 17, 18, 19 are also electrically isolated from each other.

[0079] Therefore, the first phase of the power supply is electrically connected to the first input wire 54 of the stator 50 via the feeder line, the first contact 17, and the first input terminal 14. Therefore, the second phase of the power supply is electrically connected to the second input wire 55 of the stator 50 via the feeder line, the second contact 18, and the second input terminal 15. Therefore, the third phase of the power supply is electrically connected to the third input wire 56 of the stator 50 via the feeder line, the third contact 19, and the third input terminal 16.

[0080] Therefore, current flows from the first phase of the power supply through the first winding to the star point of the stator 50. Similarly, current flows from the second phase of the power supply through the second winding to the star point of the stator 50. Similarly, current flows from the third phase of the power supply through the third winding to the star point of the stator 50.

Claims

1. An apparatus for impregnating a stator (50) of an electric machine, the apparatus comprising: a container (30) for receiving at least one stator (50) to be impregnated, wherein the container (30) is for receiving a liquid impregnating agent, a plurality of input terminals (14, 15, 16) - in particular exactly three input terminals (14, 15, 16), the input terminals being for connecting input wires (54, 55, 56) of the winding of the stator (50) to be impregnated, a plurality of output terminals (41, 42, 43) - in particular exactly three output terminals (41, 42, 43), the output terminals being for connecting output wires (51, 22, 53) of the winding of the stator (50) to be impregnated.

2. The apparatus according to claim 1, characterized in that the container (30) is configured in a cuboid shape and has a bottom plate (31), a first side wall (33), a second side wall (34), a first end wall (35) and a second end wall (36), the first side wall (33) is opposite to the second side wall (34), and the first end wall (35) is opposite to the second end wall (36).

3. The apparatus according to any one of the preceding claims, characterized in that the apparatus comprises a terminal group (40) containing the output terminals (41, 42, 43), the output terminals (41, 42, 43) of the terminal group (40) are electrically connected to each other.

4. The apparatus according to any one of the preceding claims, characterized in that the apparatus comprises a plurality of terminal units (11, 12, 13), each terminal unit having an input terminal (14, 15, 16), the input terminals (14, 15, 16) of the terminal units (11, 12, 13) are electrically isolated from each other.

5. The apparatus according to claim 4, characterized in that the terminal units (11, 12, 13) respectively have contacts (17, 18, 19) for connecting to a power supply, the contacts (17, 18, 19) of the terminal units (11, 12, 13) are respectively electrically connected to the input terminals (14, 15, 16) of the terminal units (11, 12, 13).

6. The apparatus according to claim 5, characterized in that the apparatus comprises a power supply - in particular a three-phase power supply, the power supply has a plurality of feed wires - in particular exactly three feed wires, each feed wire is respectively electrically connected to one of the contacts (17, 18, 19).

7. The apparatus according to any one of claims 4 to 6, characterized in that the terminal units (11, 12, 13) are fixed on the walls (33, 34, 35, 36) of the container (30), the terminal units (11, 12, 13) pass through the walls (33, 34, 35, 36) of the container (30), the input terminals (14, 15, 16) are respectively arranged on the side of the walls (33, 34, 35, 36) opposite to the contacts (17, 18, 19).

8. The apparatus according to any one of the preceding claims, characterized in that the container (30) includes a drain port for discharging the liquid impregnating agent.

9. The device according to any one of the preceding claims, characterized in that the device comprises a storage tank for storing a liquid impregnating agent, the storage tank is hydraulically connected to a container (30) such that the impregnating agent can be conveyed from the storage tank to the container (30) and from the container (30) to the storage tank.

10. A method of impregnating a stator (50) of an electric machine using the device according to any one of the preceding claims, the method comprising the steps of: placing the stator (50) to be impregnated into the container (30); connecting the windings of the stator (50) to a power supply; heating the stator (50) by passing a current through the windings during a preheating period; filling the container (30) with the impregnating agent; holding the stator (50) in the impregnating agent while passing an additional current through the windings during an impregnation period; draining excess impregnating agent from the container (30); hardening the impregnating agent located on the windings while passing an additional current through the windings during a hardening period; disconnecting the windings of the stator (50) from the power supply; removing the impregnated stator (50) from the container (30).

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