CA2570941A1 - Method and device for cooling of electric motors - Google Patents
Method and device for cooling of electric motors Download PDFInfo
- Publication number
- CA2570941A1 CA2570941A1 CA002570941A CA2570941A CA2570941A1 CA 2570941 A1 CA2570941 A1 CA 2570941A1 CA 002570941 A CA002570941 A CA 002570941A CA 2570941 A CA2570941 A CA 2570941A CA 2570941 A1 CA2570941 A1 CA 2570941A1
- Authority
- CA
- Canada
- Prior art keywords
- cooling
- cooling medium
- motor
- stator
- rotor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K9/00—Arrangements for cooling or ventilating
- H02K9/19—Arrangements for cooling or ventilating for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Motor Or Generator Cooling System (AREA)
Abstract
Method for cooling of electric motors, particularly motors for trawl winches.
A tubular motor housing is covered at each end by an end lid with a bearing, for accommodating a rotor which is arranged in a stator with an intermediate tubular interstice connecting the ends of the motor. Cooling medium is introduced in a void at one end of the motor, for receiving heat from electrical components, and the cooling medium is circulated through a cooling device. The cooling is made more efficient by pumping cooling medium through the interstice between the rotor and the stator.
A tubular motor housing is covered at each end by an end lid with a bearing, for accommodating a rotor which is arranged in a stator with an intermediate tubular interstice connecting the ends of the motor. Cooling medium is introduced in a void at one end of the motor, for receiving heat from electrical components, and the cooling medium is circulated through a cooling device. The cooling is made more efficient by pumping cooling medium through the interstice between the rotor and the stator.
Description
Method and Device for Cooling of Electric Motors The invention relates to a method for cooling of electric motors, and a device utilizing this method on electric motors. It relates particularly to electric motors for trawl winches.
Background Trawl winches are traditionally hydraulic powered. Recently, electric motors have been used for this purpose. However, prior art electric motor concepts have been space demanding and heavy. One reason for this has been the demand for short time high output at lowering, towing and pulling in, which requires oversized electromagnetic components to avoid overheating. When running slowly, with slow moving motors, air based cooling will be very low.
This has created a need for developing electric motors with reduced dimensions, which can produce a higher output through more efficient cooling.
From EP patent application 919 512 it is known to cool an electric motor without letting the cooling medium contact the electrically active parts. This is achieved by making the motor housing being double walled for circulating cooling liquid through passages in one end cover of the motor. This design is neither economically nor technically satisfactory.
From EP patent specification 402 517 there is known an electric motor with a closed cooling compartment with cooling fins on the stator. Cooling medium is supplied to the cooling compartment and also to the parts of the motor adjoining the cooling compartment. The design of such a cooling compartment requires an extensive intervention in the motor design. This proposal will also not provide optimal cooling.
Object The main object of the invention is to provide an electric motor with a substantial higher output to meet high output demands without overheating. Thus, it is an object to provide a motor, particularly for trawl winches, with a cooling system ensuring effective absorption and dissipation of heat energy at its site of generation, wherein the equipment for cooling is as simple as possible.
It is a particular object to provide a method and a device which can be implemented with least possible modification of existing motors.
The Invention The method according to the invention is adapted for cooling of electric motors, and particularly trawl winches, when the motor housing is covered at each end with a shield having a bearing for accommodating a rotor which is arranged in a stator with an intermediate tubular magnetic slot. Cooling medium is introduced in a void at one end of the motor and pumped through the interstice between the rotor and the stator for transfer of heat from electrical components to the cooling medium. The cooling medium is then circulated through a cooling device. Surprisingly it has been found, that it is possible to achieve efficient cooling by pumping the cooling medium through the interstice between the stator and the rotor of the motor. Thus, a standard electrical motor used according to the invention can provide a substantially higher load.
A number of different liquids may be used as internal liquid and also as external liquid. Liquids may be selected according to the specific use and circumstances, also oil and water may be used as respectively internal and external liquids.
The invention can be realized particularly simply by pumping the cooling medium at one end of the motor and provide for an outlet at the other end.
The invention can be realized with a prior art electric motor with a tubular housing, each end of which being covered by a closed end shield with a bearing, for accommodating a rotor being arranged in a stator with an intervening tubular magnet slot and with inlet and outlet means on the electric motor, for cooling medium circulating through a cooling device by means of a circulation pump.
To conduct this method, a tubular motor housing covered at each end with an end lid having a bearing, for accommodating a rotor arranged in a stator with an intermediate tubular interstice utilized as passage for the flow of cooling medium and with an inlet and an outlet on the electric motor for cooling medium which is circulated through a cooling device. This may be carried out on a prior art motor without adaptation.
Further, it is an advantage if the cooling medium inlet and the cooling medium outlet are at opposite ends of the motor.
Background Trawl winches are traditionally hydraulic powered. Recently, electric motors have been used for this purpose. However, prior art electric motor concepts have been space demanding and heavy. One reason for this has been the demand for short time high output at lowering, towing and pulling in, which requires oversized electromagnetic components to avoid overheating. When running slowly, with slow moving motors, air based cooling will be very low.
This has created a need for developing electric motors with reduced dimensions, which can produce a higher output through more efficient cooling.
From EP patent application 919 512 it is known to cool an electric motor without letting the cooling medium contact the electrically active parts. This is achieved by making the motor housing being double walled for circulating cooling liquid through passages in one end cover of the motor. This design is neither economically nor technically satisfactory.
From EP patent specification 402 517 there is known an electric motor with a closed cooling compartment with cooling fins on the stator. Cooling medium is supplied to the cooling compartment and also to the parts of the motor adjoining the cooling compartment. The design of such a cooling compartment requires an extensive intervention in the motor design. This proposal will also not provide optimal cooling.
Object The main object of the invention is to provide an electric motor with a substantial higher output to meet high output demands without overheating. Thus, it is an object to provide a motor, particularly for trawl winches, with a cooling system ensuring effective absorption and dissipation of heat energy at its site of generation, wherein the equipment for cooling is as simple as possible.
It is a particular object to provide a method and a device which can be implemented with least possible modification of existing motors.
The Invention The method according to the invention is adapted for cooling of electric motors, and particularly trawl winches, when the motor housing is covered at each end with a shield having a bearing for accommodating a rotor which is arranged in a stator with an intermediate tubular magnetic slot. Cooling medium is introduced in a void at one end of the motor and pumped through the interstice between the rotor and the stator for transfer of heat from electrical components to the cooling medium. The cooling medium is then circulated through a cooling device. Surprisingly it has been found, that it is possible to achieve efficient cooling by pumping the cooling medium through the interstice between the stator and the rotor of the motor. Thus, a standard electrical motor used according to the invention can provide a substantially higher load.
A number of different liquids may be used as internal liquid and also as external liquid. Liquids may be selected according to the specific use and circumstances, also oil and water may be used as respectively internal and external liquids.
The invention can be realized particularly simply by pumping the cooling medium at one end of the motor and provide for an outlet at the other end.
The invention can be realized with a prior art electric motor with a tubular housing, each end of which being covered by a closed end shield with a bearing, for accommodating a rotor being arranged in a stator with an intervening tubular magnet slot and with inlet and outlet means on the electric motor, for cooling medium circulating through a cooling device by means of a circulation pump.
To conduct this method, a tubular motor housing covered at each end with an end lid having a bearing, for accommodating a rotor arranged in a stator with an intermediate tubular interstice utilized as passage for the flow of cooling medium and with an inlet and an outlet on the electric motor for cooling medium which is circulated through a cooling device. This may be carried out on a prior art motor without adaptation.
Further, it is an advantage if the cooling medium inlet and the cooling medium outlet are at opposite ends of the motor.
This will be particularly advantageous if at least one of the cooling medium inlet and outlet is arranged at the end shield of the motor. This brings a particular simple cooling system, with low investment. Further, it achieves a surprising efficient heat transfer.
It also makes possible to adapt the invention at existing, installed motors, as the cooling system can be added with simple adaptations.
Example Below, the invention is described further with reference to the drawings, wherein Figure 1 shows schematically a cooling system according to the invention, while Figure 2 shows a section through a prior art motor to be included in the cooling system.
Figure 1 shows a cooling system according to the invention. It is connected to a motor 1 which is supplied with a cooling medium at an inlet 5 at one end of the motor and wherein the cooling medium is withdrawn at an outlet 6 at the other end.
From the outlet the cooling medium is circulated in a circuit with a fluid-to-fluid heat exchanger 4, powered by a circulation pump 2. A tank 3 with cooling medium provides sufficient supply of cooling medium.
Figure 2 shows a prior art DIN-standardized electric motor 1 which has two closed end shields or covers 7 and 8. Such motors will always have an interstice 9 which is open towards the cavities inside the end covers. The Figure also shows two bearings 10 and 11 arranged in the end covers. Cooling medium which is supplied through an inlet in one end covers 7 has to flow through the interstice 9 before leaving through an outlet in the opposite end cover 8.
In all electric motors, the heat generated is a limiting factor to the output.
By cooling according to the invention, the dimensional criterias for the load is changed thereby allowing higher loads for a certain size of the motor. This allows the use of smaller and lighter motors for certain purposes, e.g. operation of trawl winches, than previously possible. This will be of particular advantage when such winches are to be sized for towing when used for trawling, with low or zero rotation, but a high torque load.
It also makes possible to adapt the invention at existing, installed motors, as the cooling system can be added with simple adaptations.
Example Below, the invention is described further with reference to the drawings, wherein Figure 1 shows schematically a cooling system according to the invention, while Figure 2 shows a section through a prior art motor to be included in the cooling system.
Figure 1 shows a cooling system according to the invention. It is connected to a motor 1 which is supplied with a cooling medium at an inlet 5 at one end of the motor and wherein the cooling medium is withdrawn at an outlet 6 at the other end.
From the outlet the cooling medium is circulated in a circuit with a fluid-to-fluid heat exchanger 4, powered by a circulation pump 2. A tank 3 with cooling medium provides sufficient supply of cooling medium.
Figure 2 shows a prior art DIN-standardized electric motor 1 which has two closed end shields or covers 7 and 8. Such motors will always have an interstice 9 which is open towards the cavities inside the end covers. The Figure also shows two bearings 10 and 11 arranged in the end covers. Cooling medium which is supplied through an inlet in one end covers 7 has to flow through the interstice 9 before leaving through an outlet in the opposite end cover 8.
In all electric motors, the heat generated is a limiting factor to the output.
By cooling according to the invention, the dimensional criterias for the load is changed thereby allowing higher loads for a certain size of the motor. This allows the use of smaller and lighter motors for certain purposes, e.g. operation of trawl winches, than previously possible. This will be of particular advantage when such winches are to be sized for towing when used for trawling, with low or zero rotation, but a high torque load.
Such use of a liquid cooling medium, directly into the inner part of the electric motor, will also mean better protection against corrosion from saline air and sea water when operated in such environments. The liquid cooling medium must be an electrically non-conductive fluid. In addition, it is preferable that it have a lubricating capability, for example to lubricate the bearings. Furthermore, it should have an appropriately low viscosity, which may be in the region of 32cSt. Also it is desirable that the fluid have a water absorption capability, allowing emulsification of water in the fluid for later separation in a water absorbing filter.
While the above description points out fundamental novel features of the invention in association with a preferred embodiment thereof, it will be understood that various omissions, substitutions and changes in the form and details of the method and device may be made by those skilled in the art without departing from the scope and spirit of the invention which is set out in the claims appended hereto.
While the above description points out fundamental novel features of the invention in association with a preferred embodiment thereof, it will be understood that various omissions, substitutions and changes in the form and details of the method and device may be made by those skilled in the art without departing from the scope and spirit of the invention which is set out in the claims appended hereto.
Claims (5)
1. Method for cooling of electric motors, particularly motors for trawl winches, with a tubular motor housing being covered at each end by an end shield with a bearing, for accommodating a rotor which is arranged in a stator with an intermediate tubular magnetic slot connecting said ends of the motor, and wherein cooling medium is introduced in a void at one end of the motor and pumped through the interstice between the rotor and the stator for transfer of heat from electrical components to the cooling medium. The cooling medium is then circulated through a cooling device.
2. Method according to claim 1, characterized in that the cooling medium is supplied at one end of the motor and withdrawn from the opposite end.
3. Device in an electric motor, particularly a motor for use with trawl winches, for conducting the method according to claim 1, with a tubular motor housing covered at each end with an end lid having a bearing, for accommodating a rotor arranged in a stator with an intermediate tubular interstice utilized as passage for the flow of cooling medium and with an inlet and an outlet on the electric motor for cooling medium which is circulated through a cooling device.
4. Device according to claim 3, characterized in that the cooling medium inlet and the cooling medium outlet are arranged at opposite ends of the electric motor.
5. Device according to claim 3 or 4, characterized in that at least one of the cooling medium inlet and outlet is arranged on an end lid of the electric motor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002570941A CA2570941A1 (en) | 2006-12-12 | 2006-12-12 | Method and device for cooling of electric motors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002570941A CA2570941A1 (en) | 2006-12-12 | 2006-12-12 | Method and device for cooling of electric motors |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2570941A1 true CA2570941A1 (en) | 2008-06-12 |
Family
ID=39521242
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002570941A Abandoned CA2570941A1 (en) | 2006-12-12 | 2006-12-12 | Method and device for cooling of electric motors |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2570941A1 (en) |
-
2006
- 2006-12-12 CA CA002570941A patent/CA2570941A1/en not_active Abandoned
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2894927C (en) | Cooling arrangement of a pump intended for pumping a liquid | |
| US8896166B2 (en) | Electric drive unit | |
| DE10141397B4 (en) | Motor driven compressor | |
| JP4682716B2 (en) | Motor cooling device | |
| SG188613A1 (en) | Permanent magnet motor with a closed cooling system | |
| US20070108852A1 (en) | Method and device for cooling of electric motors | |
| DE102011005588A1 (en) | Electric motor-cooling | |
| JP2002310088A (en) | Dry type submerged motor pump with cooling water sealed type heat exchanger | |
| WO2016170546A1 (en) | Submersible pump with cooling system for motor through surrounding water | |
| JP2015025429A (en) | Submersible motor pump | |
| EP4361470A1 (en) | Cooling and lubrication apparatus of electrical drive assembly, and electrical drive assembly | |
| EP1913676B1 (en) | Coolant pump for electric motors | |
| DE102012112379A1 (en) | Drive axle of mobile working machine e.g. industrial truck, has engine compartment and transmission chamber that are located adjacent to one another in axle housing of drive axle and are fluidly connected to each other through opening | |
| EP1398508A2 (en) | Canned centrifugal pump | |
| JP2019161899A (en) | Cooling system of rotary electric machine and cooling method of rotary electric machine | |
| CA2570941A1 (en) | Method and device for cooling of electric motors | |
| JP2001516414A (en) | Apparatus for supplying pressurized liquid to equipment, high-speed water-cooled motor / generator therefor | |
| CN104131982A (en) | Oil pump for special transformer and integrated special rectifying device | |
| US7048518B2 (en) | Pump | |
| JP2011250601A (en) | Electric motor | |
| CN112671173B (en) | Circulating cooling system and method for rotor brushless motor in unmanned boat | |
| NZ551787A (en) | Liquid cooling for an electric motor | |
| CN212033943U (en) | Self-circulation heat dissipation device for motor of submersible electric pump | |
| JP2022551076A (en) | Motor cooling structures, drive assemblies and vehicles | |
| CN109494935A (en) | The cooling system and marine propulsion of marine propulsion |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |
Effective date: 20121212 |