Compressor device

Abstract

The present disclosure relates to a compressor device, which is provided with: - a compressor element having an inlet for supplying gas and an outlet for discharging compressed gas, - a magnet-assisted motor provided with a motor housing in which a motor stator is mounted and a motor rotor is rotatably mounted in the motor stator, wherein the motor stator is provided with windings and wherein the motor housing is provided with or serves as a cooling jacket; - an oil supply line for injecting oil into the magnet-assisted motor; characterized in that the oil supply line is connected to one or more nozzles pointing to the heads or axial ends of the windings of the motor stator and is connected to the cooling jacket of the magnet-assisted motor, and the heads or axial ends of the windings are covered with a protective layer.

Description

Technical field

[0001] The present invention relates to a compressor device, which includes a magnet-assisted motor for driving the compressor device, such as a permanent magnet motor. Background art

[0002] More specifically, the present invention aims to ensure the optimal cooling of the magnet-assisted motor.

[0003] It is known that the maximum power of a magnet-assisted motor is limited by the maximum temperature of the magnet-assisted motor, especially by the maximum temperature of the stator windings.

[0004] To ensure the correct operation of the magnet-assisted motor, the temperature in these windings must not rise too high.

[0005] By cooling the magnet-assisted motor with a cooling medium such as oil, for example, the maximum power of the magnet-assisted motor can be increased.

[0006] Generally, the magnet-assisted motor is equipped with cooling channels in a magnet-assisted motor housing or sheath through which the cooling medium can flow.

[0007] This means that the heat generated must reach the cooling medium through convection of air in the stator and then through conduction of the magnet-assisted motor housing.

[0008] In other words, there is a thermal resistance between the heat in the windings and the heat in the cooling medium.

[0009] This means that the cooling of the stator windings is far from optimal, and therefore in practice, the maximum power of the magnet-assisted motor can only be increased to a limited extent. Summary of the invention

[0010] The present invention aims to solve at least one of the above and other drawbacks.

[0011] To this end, the present invention relates to a compressor device, which is equipped with:

[0012] - a compressor element having an inlet for supplying gas and an outlet for discharging compressed gas;

[0013] - a magnet-assisted motor provided with a motor housing including a motor stator and a motor rotor rotatably assembled in the motor stator, wherein the motor stator includes windings, and wherein the motor housing is provided with or serves as a cooling sheath,

[0014] - an oil supply line for allowing oil to be injected into the magnet-assisted motor,

[0015] It is characterized in that the oil supply pipeline is connected to one or more nozzles pointing to the heads or axial ends of the windings of the motor stator, and is connected to the cooling jacket of the magnet-assisted motor, and the heads or axial ends of the windings are provided with a protective layer.

[0016] The advantage is that by directly injecting oil onto the heads or axial ends of the windings, also known as "winding heads", the winding heads can be cooled more effectively.

[0017] Due to the lack of thermal resistance between the winding heads and the oil, the oil will be able to dissipate heat more effectively.

[0018] Because the winding heads are provided with a protective layer, they are protected from the oil sprayed thereon and, more importantly, from any condensates in the oil.

[0019] This will prevent any electrical problems caused by condensates.

[0020] Due to the forced cooling of the winding heads, the temperature will not increase so quickly, and thus the maximum motor power can be increased.

[0021] In a practical embodiment, the oil supply pipeline branches into two branch pipelines, where the first branch pipeline connects the oil supply pipeline to the nozzle, and the second branch pipeline connects the oil supply pipeline to the cooling jacket.

[0022] By providing two branch pipelines, a part of the oil can be directed to the cooling jacket to provide known conventional motor cooling, while the other part is directed to one or more nozzles to provide additional forced cooling of the winding heads.

[0023] For example, general motor cooling (where the oil will cool the motor housing to dissipate heat from the motor) can be provided as specific cooling directed to the winding heads, which are typically the motor hot spots.

[0024] In addition, the branched oil supply provides the possibility of adjusting the flow rate and / or temperature of each supply according to requirements or needs.

[0025] In an alternative embodiment, the oil supply pipeline is directly connected to the cooling jacket, where all the oil first enters the cooling jacket and then enters the nozzle.

[0026] When the oil has passed through the cooling jacket, the oil will be directed to the nozzle and sprayed onto the winding heads in the motor.

[0027] For example, this can be achieved by providing internal channels in the motor and / or the motor housing.

[0028] Different from the case of parallel oil flow with two branch pipelines, this serial flow provides the advantage that forced integration can be achieved.

[0029] Of course, it is not excluded that the oil is first directed to the nozzle for spraying onto the winding head and then only reaches the cooling jacket.

[0030] In an alternative embodiment, the motor stator is provided with axially oriented grooves or channels, and / or axially oriented grooves or channels are provided in the housing at the location of the motor stator.

[0031] These grooves will allow the sprayed oil to flow along the motor stator and / or the housing while providing further cooling.

[0032] The sprayed oil can also flow out between the motor rotor and the motor stator or through the laminations of the motor stator. Description of the Drawings

[0033] In order to better show the features of the present invention, some preferred embodiments of the compressor device according to the present invention will be described below with reference to the drawings as examples without any restrictive features, wherein:

[0034] Figure 1 A cross-sectional view schematically showing a part of the compressor device as claimed in the present invention is shown;

[0035] Figure 2 Is shown in more detail Figure 1 The magnet-assisted motor of

[0036] Figure 3 Is schematically shown Figure 1 A part of the compressor device shown and the associated oil circuit. Detailed Description of the Invention

[0037] Figure 1 Is a schematic view of a compressor device 1 according to the present invention.

[0038] The compressor device 1 mainly comprises a compressor element 2 and a magnet-assisted motor 3.

[0039] In this case, but not essential for the present invention, the compressor element 2 is provided with a screw compressor element.

[0040] It includes a compressor housing 4 having an inlet 5 for supplying the gas to be compressed and an outlet 6 for supplying the compressed gas.

[0041] The gas can be, for example, air, but this is not essential for the present invention.

[0042] Two cooperating screw rotors 7 are installed in the compressor housing 4, which are capable of compressing the gas sucked in by rotation.

[0043] For this purpose, the screw rotor 7 is rotatably mounted in the compressor housing 4 by means of its shaft 8 via bearings 9.

[0044] One of the two screw rotors 7 is driven by the motor.

[0045] Figure 2 The motor 3 is shown in detail.

[0046] In this case, the magnet-assisted motor 3 is a permanent magnet motor 3, but this is not essential for the present invention.

[0047] The motor 3 includes a motor housing 10, which includes a motor stator 11 and a motor rotor 12 rotatably arranged in the motor stator 11.

[0048] The motor stator 11 is provided with windings 13, which are generally arranged around a laminated iron core 14, also known as a lamination.

[0049] According to the invention, the axial ends 15 of these windings 13, also known as the "heads" of the windings 12, are provided with a protective layer 16.

[0050] This means that these heads are provided with a layer applied on, above and around the windings 13.

[0051] The protective layer 16 is preferably thermally conductive, electrically insulating and waterproof and oil-proof.

[0052] The protective layer 16 can include, for example, epoxy resin, but a polymer material is another option.

[0053] It is not excluded that the entire winding 13 or even the entire motor stator 11 has a protective layer 16, rather than only the axial ends 15 having it.

[0054] For this purpose, the protective layer 16 will extend over the entire winding 13 or over the entire motor stator 11.

[0055] The protective layer 16 is generally a thin layer, for example, 0.1 mm to 1 mm thick. Of course, it is not excluded that the thickness of the protective layer 16 is between 1 mm and 5 mm, for example.

[0056] Alternatively, the protective layer 16 can be much thicker and the axial ends 15 of the windings 13 are encapsulated in a protective material. Obviously, the entire winding 13 or the entire motor stator 11 can also be encapsulated in a protective material.

[0057] In this case, the motor housing 10 also serves as a cooling jacket 17. It is not excluded that the motor housing 10 is provided with a separate cooling jacket 17.

[0058] As Figure 1As shown, the compressor device 1 is a vertical compressor device 1, in which the motor rotor 12 of the magnet-assisted motor 3 extends along the axial direction X-X', which is vertically positioned during the normal operation of the compressor device 1, and the magnet-assisted motor 3 forms the head or upper part of the compressor device 1, and the compressor element 2 forms the base or lower part of the compressor device 1.

[0059] Furthermore, according to the present invention, an oil supply line 18 is also provided to inject oil into the magnet-assisted motor 3.

[0060] Figure 3 The oil supply line 18 is shown. It can be seen that in this example, it is part of the oil circuit 19, but it is not essential for the present invention.

[0061] In this case, the oil circuit 19 is arranged to first direct all the oil to the motor 3 and then to the compressor element 2.

[0062] The oil circuit 19 flows back from the compressor element 2 via the oil reservoir 20 and the oil cooler 21 to the motor 3 to form a closed loop for the oil.

[0063] The oil supply line 18 is connected to one or more nozzles 22, and the one or more nozzles are directed at the head 15 or the axial end 15 of the winding 13 of the motor stator 11 and the cooling jacket 17 of the motor 3.

[0064] These nozzles 22 directly inject the oil in the form of an oil stream or a "jet" onto the head 15 of the winding 13.

[0065] It is not excluded that the nozzles 22 atomize the oil, that is, inject the oil in the form of small droplets onto the head 15 of the winding 13.

[0066] In the example shown, the above-mentioned nozzles 22 are located at the axial ends 23 of the motor stator 11 and the motor rotor 12, where the nozzles 22 are axially oriented.

[0067] A plurality of nozzles 22 can be provided, for example, two to eight, and are preferably symmetrically positioned around the axis X-X' of the motor rotor 12.

[0068] In this case, the nozzles 22 are located at the top, that is, at the axial end 23 of the motor 3 facing away from the compressor element 2, but it is not excluded that additional or alternative nozzles 22 are located at the bottom, that is, on the axial end 23 of the motor 3 pointing to the compressor element 2.

[0069] The nozzles 22 can also be located on the side of the motor housing 10, that is, at the position of the jacket 24 of the motor housing 10. In this case, the nozzles 22 are radially directed so that they point to the head 15 of the winding 13.

[0070] Also in this case, the nozzle 22 can be located at the top as well as at the bottom.

[0071] The exact position of the nozzle 22 generally depends on the design of the motor 3, and in particular on the design of the motor housing 10.

[0072] If the motor housing 10 does not allow oil supply through the motor housing 10, an alternative solution is to design the motor rotor 12 to be at least partially hollow and integrate the nozzle 22 in the hollow motor rotor 12.

[0073] Obviously, the nozzle 22 points radially outwards, while radial channels are provided in the motor rotor 12 to allow oil to pass through.

[0074] As described above, the oil supply line 18 is connected to the nozzle 22 and the cooling jacket 17.

[0075] This means that the oil guided through the oil supply line 18 to the motor 3 will enter both the nozzle 22 and the cooling jacket 17.

[0076] In the example shown, this is done in parallel, since the oil supply line 18 branches into two branch lines 25a, 25b, as Figure 3 shown.

[0077] The first branch line 25a connects the oil supply line 18 to the nozzle 22, and the second branch line 25b connects the oil supply line 18 to the cooling jacket 17.

[0078] In this case, the compressor device 1 is also equipped with means 26 for controlling the amount of oil flowing to the first and second branch lines 25a, 25b, and a controller 27 for controlling the control means 26.

[0079] This allows control of the amount of oil flowing to the nozzle 22 between no oil and all or almost all of the oil.

[0080] If the control means 26 are not provided, the oil will be continuously ejected through the nozzle 22.

[0081] In this case, the control means 26 are designed as a three-way valve 28, but can also be designed as a conventional valve installed in one of the two branch lines 25a, 25b.

[0082] Furthermore, in this example, the compressor device 1 has measuring means 29 for determining the temperature of the head 15 or the axial end 15 of the winding 13 of the motor stator 11, and the controller 27 is provided with an algorithm for controlling the regulating means 26 based on the temperature of the head or the axial end 15 of the winding 13 of the motor stator 11.

[0083] These measuring means 29 include, for example, temperature sensors.

[0084] In addition, in the illustrated example, an axially oriented groove 30 or passage is also provided at the location of the motor stator 11 within the motor housing 10.

[0085] Just like the nozzle 22, these grooves 30 can be positioned symmetrically about the axis X-X' of the motor rotor 12.

[0086] Alternatively or additionally, axially oriented grooves 30 or passages can also be provided within the motor stator 11 itself.

[0087] The oil injected through the nozzle 22 can flow out along these passages or grooves 30.

[0088] The oil can also flow out through the space between the motor rotor 12 and the motor stator 11 or through the laminations 14 of the motor stator 11.

[0089] The operation of the compressor device 1 is very simple and is described as follows.

[0090] During the operation of the compressor device 1, the compressor element 2 will be driven by the magnet-assisted motor 3.

[0091] The screw rotors 7 will compress the gas drawn in through their cooperative action.

[0092] During operation, oil will be injected into the compressor element 2 as well as the motor 3.

[0093] The oil supply line 18 will first direct all the oil to the motor 3.

[0094] The second branch line 25b will direct the oil to the cooling jacket 17.

[0095] This oil will be able to draw heat from the motor housing 10 in a known manner to cool the motor 3.

[0096] The oil is also directed to the nozzle 22 through the oil supply line 18 and the first branch line 25a.

[0097] As described above, the nozzles 22 are positioned in place to allow them to atomize the oil at the axial ends 15 of the windings 13 of the motor stator 11.

[0098] The small oil droplets will be able to draw heat from these axial ends 15 of the windings 13, and then, compared to the oil flowing through the cooling jacket 17, these axial ends will be cooled more effectively.

[0099] The protective layer 16 on the axial ends 15 of the windings 13 protects the windings from the oil injected onto the windings.

[0100] The controller 27 will control how much oil is directed to the nozzle 22 through the first branch line 25a.

[0101] For this purpose, in this case, the controller 27 is provided with an algorithm to control the control device 26 based on the temperature of the windings 13 of the motor stator 11.

[0102] In this case, the above algorithm causes the controller 27 to control the control device 26 such that when the temperature of the axial end 15 of the winding 13 measured by the measuring device 29 is lower than a predetermined maximum temperature T max no oil will flow to the first branch pipeline 25a.

[0103] In other words, oil will only be atomized onto them when the temperature of the heads 15 of the windings 13 rises too high and cooling is required.

[0104] It is also not excluded to control the amount of oil guided to the nozzle 22 through the first branch pipeline 25a based on the measurement results of the measuring device 29.

[0105] Then, the atomized oil can flow downward toward the other heads or axial ends 15 of the winding 13 via three paths to also cool these axial ends 15 of the winding 13.

[0106] These three paths are:

[0107] - via the aforementioned axially oriented grooves 30 or channels provided in the motor stator 11, between the motor housing 10 and the motor stator 11;

[0108] - between the motor rotor 12 and the motor stator 11;

[0109] - through the laminations 14 of the motor stator 11.

[0110] The oil will also cool the motor stator 11 and possibly the motor rotor 12.

[0111] In this case, the oil will also flow past the motor 3 under the action of gravity in the direction of the compressor element 2.

[0112] However, even if the vertical compressor element 1 is not involved, the oil will still flow toward the compressor element 2 by the force of the oil pressure and / or vacuum generated by the compressor element 2.

[0113] When the oil has reached the bottom of the motor 3, it will be guided through the oil passage 19 to the compressor element 2 to be sprayed, for example, into the compressor housing 4 or the bearing 9.

[0114] The oil will leave the compressor device 1 together with the compressed gas through the outlet 6.

[0115] The oil separator separates the oil, and the oil will pass along the oil reservoir 20 through the oil passage 19 and then enter the oil cooler 21 to be sprayed back into the motor 3 from there.

[0116] Although the above examples show and describe the oil supply to the nozzle 22 and the cooling jacket 17 in parallel, it is not excluded that this is done serially.

[0117] This means that the oil supply to the nozzle 22 and the cooling jacket 17 can also be arranged in series, where the oil supply line 18 is directly connected to the above-mentioned cooling jacket 17 such that all the oil first reaches the cooling jacket 17 and then reaches the nozzle 22.

[0118] In other words, no branch lines 25a, 25b are provided here.

[0119] In this case, a passage is provided in the motor housing 10 which allows the oil to be guided to the nozzle 22 for injection into the motor 3 after being guided through the cooling jacket 17.

[0120] It should also be noted that in this case, the oil supply line 18 is connected to the nozzle 22, although not directly, but through the cooling jacket 17 and any other passage in the motor housing 10.

[0121] This method has the advantage that no additional measures are required to regulate the oil supply.

[0122] The present invention is in no way limited to the embodiments described by way of example and shown in the drawings, but rather the compressor device according to the present invention can be realized in all shapes and sizes without going beyond the scope of the present invention.

Claims

1. A compressor device, the compressor device being provided with: - A compressor element (2), the compressor element having an inlet (5) for supplying gas and an outlet (6) for discharging compressed gas, - Magnet-assisted motor (3), said magnet-assisted motor being provided with a motor housing (10), a motor stator (11) being mounted in said motor housing, and a motor rotor (12) being rotatably mounted in said motor stator (11), wherein, The motor stator (11) is provided with a winding (13), and wherein, the motor housing (10) is provided with or serves as a cooling jacket (17); - An oil supply line (18), the oil supply line being used for injecting oil into the magnet-assisted motor (3); It is characterized in that the oil supply line (18) is connected to one or more nozzles (22) pointing to the head or axial end (15) of the winding (13) of the motor stator (11), and is connected to the cooling jacket (17) of the magnet-assisted motor (3), and the head or axial end (15) of the winding (13) is covered with a protective layer (16), Wherein, the oil supply line (18) branches into a first branch line (25a) and a second branch line (25b), wherein, the first branch line (25a) connects the oil supply line (18) to the nozzle (22), and the second branch line (25b) connects the oil supply line (18) to the cooling jacket (17); and the compressor device (1) is further provided with control means (26) for controlling the amount of oil flowing to the first branch line (25a) and the second branch line (25b) and a controller (27) for controlling the control means (26).

2. The compressor device according to claim 1, wherein, The protective layer (16) is thermally conductive, electrically insulating and resistant to water and oil.

3. The compressor device according to claim 2, characterized in that, The protective layer (16) comprises epoxy resin.

4. The compressor device according to any one of claims 1 to 3, characterized in that, The nozzle (22) is located at one or more of the following positions in the motor housing (10): - At the axial ends (23) of the motor stator (11) and the motor rotor (12), wherein, the nozzle (22) is axially oriented, - At the side of the sheath (24) passing through the motor housing (10), wherein, the nozzle (22) is radially oriented.

5. The compressor device according to any one of claims 1 to 3, characterized in that The motor rotor (12) is at least partially hollow, and at least one of the nozzles (22) is integrated in the motor rotor (12).

6. The compressor device according to claim 1, characterized in that, The compressor device (1) is further provided with measuring means (29) for determining the temperature of the head or axial end (15) of the winding (13) of the motor stator (11), and the controller (27) is provided with an algorithm for controlling the control means (26) based on the temperature of the head or axial end (15) of the winding (13) of the motor stator (11).

7. The compressor device according to claim 6, characterized in that, The algorithm causes the controller (27) to control the control device (26) such that when the temperature of the head or axial end (15) of the winding (13) is lower than a preset maximum temperature T max no oil will flow to the first branch pipeline (25a).

8. The compressor device according to any one of claims 1 to 3, characterized in that, The oil supply line (18) is directly connected to the cooling jacket (17), wherein all the oil first reaches the cooling jacket (17) and then reaches the nozzle (22).

9. The compressor device according to any one of claims 1 to 3, characterized in that The protective layer (16) extends over the entire winding (13) or over the entire motor stator (11).

10. The compressor device according to any one of claims 1-3, characterized in that, At least the head or axial end (15) of the winding (13) is encapsulated in a protective material.

11. The compressor device according to any one of claims 1-3, characterized in that, The oil supply line (18) is part of an oil circuit (19) which is also part of the compressor device (1), wherein the oil circuit (19) is designed such that all oil is first directed to the magnet-assisted motor (3) and then to the compressor element (2).

12. The compressor device according to any one of claims 1 to 3, characterized in that, The motor stator (11) is provided with axially oriented grooves (30) or channels, and / or the motor housing (10) is provided with axially oriented grooves (30) or channels at the location of the motor stator (11).

13. The compressor device according to any one of claims 1-3, characterized in that, The nozzle (22) atomizes the oil.

14. The compressor device according to any one of claims 1-3, characterized in that, The magnet-assisted motor (3) is a permanent magnet motor (3).

15. The compressor device according to any one of claims 1-3, characterized in that, The compressor element (2) is a screw compressor element (2).

16. The compressor device according to any one of claims 1-3, characterized in that, The compressor device (1) is a vertical compressor device (1), wherein the motor rotor (12) of the magnet-assisted motor (3) extends in the vertically oriented axial direction (X-X') during normal operation of the compressor device (1), wherein the magnet-assisted motor (3) forms the head or upper part of the compressor device (1), and the compressor element (2) forms the base or lower part of the compressor device (1).

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