Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K5/00—Casings; Enclosures; Supports
  • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
  • H02K5/12—Casings or enclosures characterised by the shape, form or construction thereof specially adapted for operating in liquid or gas
  • H02K5/132—Submersible electric motors
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K1/00—Details of the magnetic circuit
  • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D13/00—Pumping installations or systems
  • F04D13/02—Units comprising pumps and their driving means
  • F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
  • F04D13/08—Units comprising pumps and their driving means the pump being electrically driven for submerged use
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K1/00—Details of the magnetic circuit
  • H02K1/02—Details of the magnetic circuit characterised by the magnetic material
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K1/00—Details of the magnetic circuit
  • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
  • H02K1/22—Rotating parts of the magnetic circuit
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K3/00—Details of windings
  • H02K3/42—Means for preventing or reducing eddy-current losses in the winding heads, e.g. by shielding
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K5/00—Casings; Enclosures; Supports
  • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
  • H02K5/12—Casings or enclosures characterised by the shape, form or construction thereof specially adapted for operating in liquid or gas
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K5/00—Casings; Enclosures; Supports
  • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
  • H02K5/16—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields
  • H02K5/167—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields using sliding-contact or spherical cap bearings
  • H02K5/1677—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields using sliding-contact or spherical cap bearings radially supporting the rotor around a fixed spindle; radially supporting the rotor directly
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
  • H02K7/08—Structural association with bearings
  • H02K7/09—Structural association with bearings with magnetic bearings
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K2201/00—Specific aspects not provided for in the other groups of this subclass relating to the magnetic circuits
  • H02K2201/03—Machines characterised by aspects of the air-gap between rotor and stator
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K2213/00—Specific aspects, not otherwise provided for and not covered by codes H02K2201/00 - H02K2211/00
  • H02K2213/03—Machines characterised by numerical values, ranges, mathematical expressions or similar information

Definitions

• the invention relates to a synchronous reluctance motor for driving an underwater pump with a stator-rotor arrangement, wherein the rotor comprises a flow barrier cut for the expression of one or more magnetic pole pairs.
• the invention relates to an underwater pump with such a drive motor.
• Submersible motor pumps are used to convey liquid media in boreholes.
• the outside of the housing of the motors is completely or partially wetted by the pumped medium, usually groundwater.
• the pump drive motors used are encapsulated to prevent the penetration of the fluid into the engine compartment.
• the engine compartment is filled with a suitable liquid medium, preferably with a water-glycol mixture or oil, which wets both the unprotected rotor and in the case of an unprotected stator, the stator together with plastic-insulated winding wires or in the case of a protected stator, a can.
• a suitable liquid medium preferably with a water-glycol mixture or oil, which wets both the unprotected rotor and in the case of an unprotected stator, the stator together with plastic-insulated winding wires or in the case of a protected stator, a can.
• the injected medium ensures sufficient cooling capacity of the engine.
• the medium ensures a constant lubrication of the hydrodynamic plain bearings and may provide a desirable anti-corrosive effect of the active parts.
• Submersible motor pump units are installed in suitable boreholes in the area of the pumped medium.
• the drilling costs vary depending on the drilling depth and the required Bohrioch bemessers.
• Straight borehole depths of a few hundred meters cause enormous costs, which are halted for example by limiting the permissible Bohrioch bemessers.
• the active part length of the motor must be correspondingly increased.
• the associated very slim design of the unit can increase the ratio of rotor length to the rotor diameter.
• the active part length of the rotor is at least twice as large as the rotor diameter. For manufacturing reasons, therefore, a relatively large air gap must be realized, which is significantly larger than conventional motors fails.
• the air gap dimensions of submersible motors are more than twice the air gap dimensions of conventional motors.
• the object of the invention is therefore to modify a known synchronous refuktance motor in such a way that it can also be used in an underwater pump is, however, without having to accept appreciable losses in efficiency and power factor.
• a synchronous Reiuktanzmotor which has a stator and a stator operatively connected to the rotor.
• the rotor comprises a flux barrier cut for the expression of one or more pairs of magnetic poles.
• the rotor of the synchronous reluctance machine may preferably be provided with a cylindrical soft magnetic element coaxially arranged on the rotor axis.
• the soft magnetic element preferably comprises flux-conducting and flux-barrier sections which differ from each other in a different degree of magnetic permeability.
• the large magnetic conductivity portion is designated as the d axis of the rotor and the portion of comparatively lower conductivity as the q axis of the rotor.
• An optimal torque yield occurs when the d-axis has the largest possible magnetic conductivity and the q-axis has the lowest possible magnetic conductivity.
• This requirement can be achieved by forming a plurality of air-filled recesses in the soft magnetic element along the q-axis.
• the soft magnetic element is a laminated core, which is constructed from a plurality of stacked in the axial direction of the rotor sheets.
• This design prevents the occurrence of eddy currents in the soft magnetic element, in particular, offers a Construction of the laminated core according to the technical teaching of US 5,818,140, to which reference is expressly made in this context.
• ferrofluid According to the filling medium previously used in the engine compartment is replaced by a ferrofluid.
• a suitable choice of the ferrofluid used leads to a relative permeability of p R > 1.
• the increase in the permeability in the air gap corresponds in its effect to a geometric reduction of the magnetic air gap.
• the magnetically active air gap is correspondingly reduced.
• the greater the value of the permeability in the air gap the more advantageous is the efficiency and power factor of the synchronous reluctance motor used.
• the interaction between rotor and stator is enhanced.
• certain engine principles can also be used where, due to the technical conditions, a comparatively large air gap condition.
• ferrofluid allows the use of a synchronous reluctance motor for driving an underwater pump with a satisfactory efficiency and power factor.
• the fluid used improves the heat dissipation in the engine compartment.
• hydrodynamic sliding bearings are constantly lubricated and the ferrofluid can have a corrosion-protective effect on the active parts of the synchronous reluctance motor used.
• the ferrofluid has one or more magneto-responsive components which are magnetizable and typically superparamagnetic.
• the magnetic components can be present in different forms in a carrier liquid.
• the combination of particles and carrier liquid forms the ferrofluid.
• the components are present as particles suspended in the carrier liquid.
• the individual particles are colloidally suspended in the carrier liquid.
• the particle size is in the nano range, preferably between 1 nm and 10 nm, with particular particle sizes in the range between 5 nm and 10 nm prove to be favorable.
• One or more particles suitably consist of at least one of iron, magnetite, cobalt or a special alloy.
• the particles may be provided with a surface coating, in particular a polymeric coating. It is possible to add a surface-active substance which adheres to the surface of the particles as a monomolecular layer.
• the radicals of polar molecules of the surfactant repel each other and thus prevent clumping of the particles.
• the viscosity of the ferrofluid used is in the range of that of water, i. H. in the range of about 1 mPa-s at 20 ° C.
• the use of the ferrofluid entails a negative side effect, since the increased permeability in the engine compartment also increases scattering losses that occur. Unlike air-filled engines, the spread of the scattering field lines is no longer inhibited but encouraged, which is why the losses occur significantly.
• means may be provided in the region of at least one winding head of the stator for reducing the forehead control occurring.
• one or more elements are placed in this area to displace the ferrofluid in this area.
• Suitable elements are one or more plastic bodies, which are preferably attachable to one or more winding heads or can be attached to these.
• Alternative means for reducing the occurrence of frontal scattering arise by casting the winding heads or foaming the space around the winding heads. Basically, materials with non-magnetic properties are suitable.
• the rotor of the synchronous reluctance machine preferably consists of a laminated rotor core.
• the rotor core has individual flow barriers for the expression of one or more pairs of poles. Flush barriers are formed in a conventional manner by recesses in the rotor core, which are usually filled with air. In this case, there is a risk that the ferrofluid gets into the cavity of the river barriers.
• the rotor or at least a part of the rotor is designed encapsulated in order to seal off the rotor body from the ferrofluid.
• one or more flow barriers can be sealed separately and protected against undesired liquid entry. It is also possible to fill the flow barriers with a suitable material, such as plastic, to prevent the ingress of liquid.
• the invention further relates to an underwater pump with a synchronous reluctance motor driving the pump according to the features of the motor according to the invention or an advantageous embodiment of the synchronous reluctance motor.
• the underwater pump obviously has the same advantages and properties as the synchronous reluctance motor according to the invention or an advantageous embodiment of the motor, for which reason a renewed description is dispensed with at this point.
• FIG. 1 shows a schematic longitudinal section of the synchronous reluctance motor according to the invention
• Figure 2 is a schematic cross-sectional view of the rotor of the synchronous reluctance motor according to the invention.
• Figure 3 a detail of the stator of the synchronous reluctance motor according to the invention.
• the synchronous reluctance motor 10 shown in FIG. 1 has a conventional stator 11 and a rotor 12 which is rotatably mounted to the stator 11 and which is itself arranged coaxially on the shaft 13.
• the rotor body consists of a laminated package, for example a laminated core, wherein the individual layers or sheets are stacked in the axial direction of the shaft 13.
• a schematic representation of a single layer is shown in FIG.
• the distance between the rotor and stator walls is called the air gap.
• the motor interior is filled with a ferrofluid 20 in FIG. 1, which increases the permeability in the region between stator 11 and rotor 12 and compensates for the comparatively large geometric distance.
• the interaction between rotor 12 and stator 11, ie the reluctance force, is increased by the increased permeability.
• the ferrofluid 20 used consists of a few nanometer sized magnetic particles which are colloidally suspended in a suitable carrier liquid.
• the viscous properties of the ferrofluid 20 used are selected so that the friction between the rotor and ferrofluid 20 is as small as possible.
• the ferrofluid 20 has a viscosity in the order of the viscosity of water.
• Occurring scattering losses in the region of the winding heads 15 of the stator 1 1 should be reduced by one or more plastic body 16 as much as possible.
• the plastic body is mounted on the corresponding winding head 15 and surrounds this to complete displacement of the ferrofluid.
• FIG. 3 shows a detailed view of a cross section through the stator pack 1 with winding space 17.
• a slot wedge 30 is provided, which displaces the ferrofluid in the slot slot to form a magnetic slot
• FIG. 2 shows a cross section through the rotor core 12.
• the drawing schematically illustrates a single flow barrier of a rotor layer 41.
• the otherwise air-filled recess 40 of the rotor layer 41 is completely filled or foamed with a plastic-like material in order to prevent possible entry of the fluid.
• the complete rotor body 12, as indicated in Figure 1 be executed encapsulated.
• the rotor surface is completely coated with a suitable material 50 to protect the rotor body from liquid ingress.

Landscapes

• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Iron Core Of Rotating Electric Machines (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Synchronous Machinery (AREA)
• Rotary Pumps (AREA)
• Details And Applications Of Rotary Liquid Pumps (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
• Motor Or Generator Frames (AREA)

Priority Applications (8)

Applications Claiming Priority (2)

Publications (2)

Family

ID=48087558

Family Applications (1)

Country Status (11)

Families Citing this family (6)

Citations (1)

Family Cites Families (20)

• 2012
  • 2012-04-04 DE DE102012205567A patent/DE102012205567A1/de not_active Withdrawn
• 2013
  • 2013-02-14 CA CA2869344A patent/CA2869344A1/en not_active Abandoned
  • 2013-04-03 RU RU2014144348A patent/RU2014144348A/ru unknown
  • 2013-04-03 CN CN201380015920.4A patent/CN104285360A/zh active Pending
  • 2013-04-03 KR KR1020147027821A patent/KR20140141632A/ko not_active Ceased
  • 2013-04-03 US US14/390,487 patent/US20150171698A1/en not_active Abandoned
  • 2013-04-03 EP EP13715657.6A patent/EP2834905A2/de not_active Withdrawn
  • 2013-04-03 WO PCT/EP2013/057002 patent/WO2013150061A2/de active Application Filing
  • 2013-04-03 JP JP2015503868A patent/JP2015514387A/ja active Pending
  • 2013-04-03 BR BR112014024013A patent/BR112014024013A8/pt not_active Application Discontinuation
• 2014
  • 2014-09-12 ZA ZA2014/06729A patent/ZA201406729B/en unknown

Patent Citations (1)

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