Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K19/00—Synchronous motors or generators
  • H02K19/02—Synchronous motors
  • H02K19/10—Synchronous motors for multi-phase current
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K21/00—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets
  • H02K21/12—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets
  • H02K21/14—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets with magnets rotating within the armatures
• • 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
  • H02K1/12—Stationary parts of the magnetic circuit
  • H02K1/16—Stator cores with slots for windings
• • 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
  • H02K1/27—Rotor cores with permanent magnets
  • H02K1/2706—Inner rotors
  • H02K1/272—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis
  • H02K1/274—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets
  • H02K1/2753—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets the rotor consisting of magnets or groups of magnets arranged with alternating polarity
  • H02K1/276—Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM]
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
  • H02K11/04—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for rectification
  • H02K11/049—Rectifiers associated with stationary parts, e.g. stator cores
  • H02K11/05—Rectifiers associated with casings, enclosures or brackets
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
  • H02K11/30—Structural association with control circuits or drive circuits
• • 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
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
  • H02P2207/07—Doubly fed machines receiving two supplies both on the stator only wherein the power supply is fed to different sets of stator windings or to rotor and stator windings

Definitions

• the present invention relates to a rotating electrical machine with optimized configuration.
• the invention finds a particularly advantageous, but not exclusive, application with high power reversible electrical machines that can operate in alternator mode and in motor mode coupled with a host element, such as a gearbox.
• the rotating electrical machines comprise a stator and a rotor secured to a shaft.
• the rotor may be integral with a driving shaft and / or driven and may belong to a rotating electrical machine in the form of an alternator, an electric motor, or a reversible machine that can operate in both modes.
• alternator mode when the rotor is rotating, it induces a magnetic field to the stator which transforms it into electric current to power the vehicle's electrical consumers and recharge the battery.
• motor mode the stator is electrically powered and induces a magnetic field driving the rotor in rotation to starter the engine and / or participate in the traction of the vehicle, independently or in combination with the engine.
• the stator is mounted in a housing configured to rotate the shaft on bearings by bearings. Furthermore, the stator comprises a body consisting of a stack of thin sheets forming a ring, whose inner face is provided with notches open inward to receive an electrical coil formed by phase windings. These windings pass through the notches of the stator body and form buns protruding from both sides of the stator body.
• the phase windings are obtained for example from a continuous wire covered with enamel or from conductive elements in the form of pins connected together by welding. These windings are polyphase windings connected in star or delta whose outputs are connected to an inverter also operating as a bridge rectifier.
• FIG. 1 represents characteristic curves of torque and power as a function of the rotational speed of such a rotating electrical machine respectively in the motor mode M_mth (see characteristic curve of torque C1 and power characteristic curve C2) and in FIG. generator mode M_gen (see characteristic curve of torque C3 and power characteristic curve C4).
• a defluxing range P_def is defined by reference to a ratio between a maximum rotation speed at constant torque N1 divided by the maximum rotational speed N2 of the electric machine.
• This defluxing ratio being high (greater than 2.5), the machine can operate at high speed while being in a state of quasi-short circuit.
• the machine In order to optimize the operation of the machine, in particular to achieve high operating speeds and therefore high power, it is necessary that the machine has a good steady state short-circuit current.
• This optimization of the machine must also take into account other parameters such as the compactness of the machine which is an important parameter for the integration of said machine into the vehicle, as well as the thermal behavior of the machine which is also a parameter important both for the safety of the users and not to damage the machine.
• the invention therefore aims to guarantee the holding of the short-circuit current in steady state while optimizing the compactness and the thermal characteristics of the electric machine.
• the present invention relates to a rotating electric machine of a motor vehicle.
• the machine comprises a rotor extending along an axis of rotation and comprising at least one permanent magnet and a stator surrounding the rotor and comprising a body provided with a plurality of notches and an electric winding, the winding comprising phase windings arranged in the notches, each phase winding being formed by at least one conductor.
• the rotor comprises 3 or 4 or 5 pairs of poles and the stator comprises two three-phase systems each formed by three coupled phase windings. in triangle.
• the number of conductors per notch is strictly greater than 2 and each conductor has an active portion inserted into a corresponding notch, the active portion of substantially rectangular section having a radial length less than or equal to 3.6 mm.
• substantially rectangular section of wire makes it possible to improve the coefficient of filling of the conductors in the notches and thus to improve the power of the machine.
• substantially rectangular section is meant that the corners of the conductors may be slightly rounded for manufacturing issues.
• a number of conductors per notch strictly greater than two allows to have a greater degree of latitude in terms of choice of the number of turns per winding.
• the radial width of the conductors is less than or equal to 3.6 mm associated with a number of pairs of rotor poles of between 3 and 5 makes it possible to minimize the resistance of the conductors, thereby limiting the Joule losses of the conductors. All these parameters taken together therefore lead to a better thermal resistance, a better resistance of the short-circuit current in steady state and a better compactness of the rotating electrical machine.
• the rotating electrical machine can thus operate at a higher speed in a secure manner.
• the two three-phase systems are independent of one another and the rotating electrical machine comprises an inverter comprising two independent modules each connected to a three-phase system.
• the inverter is connected to a DC bus having a voltage of between 30 and 60 volts.
• an orthoradial length of an active portion of a conductor is greater than or equal to 1 .4 mm.
• an outer diameter of the stator body is between 80 mm and 180 mm.
• the outer diameter of the stator body is selected from one of the following values: 80, 90, 100, 110, 153, 161 and 180 millimeters.
• a maximum power of said rotary electrical machine is between 8 kW and 30 kW.
• the number of conductors per slot is even.
• the number of conductors per notch is 4.
• the number of conductors per notch may be equal to 6, 8 or 10.
• the conductors are aligned radially with each other within a corresponding notch.
• each phase winding is formed from a plurality of conductors in particular in the form of pins electrically connected to each other.
• the pins extend in the form of a U comprising two active parts extending in respective notches and a connecting portion connecting the two active parts.
• a phase winding is formed by welding together the free ends of the active parts of different pins.
• free ends is meant the ends of the active parts that are not connected to the connecting portion.
• each phase winding is formed from a continuous conductor.
• This continuous conductor is for example a wire.
• the conductive wire comprises active portions of substantially rectangular section and connecting portions between two adjacent active portions of rounded section, in particular substantially round.
• the conductors have a rectangular section with rounded corners.
• said rotating electrical machine comprises a coolant circuit.
• the machine is a synchronous machine.
• the machine is a permanent magnet machine.
• said rotating electrical machine takes the form of a motor, a generator, or a reversible electric machine.
• FIG. 1 shows the characteristic curves of torque and power as a function of the speed of rotation of a rotating electrical machine used in the context of the invention.
• FIG. 2 is a longitudinal sectional view of a rotating electrical machine according to an exemplary embodiment of the present invention.
• FIG. 3 is a perspective view of the wound stator and the rotor of the rotary electric machine of FIG.
• Fig. 4 is a partial cross-sectional view of the rotor and wound stator according to an exemplary embodiment of the present invention.
• FIG. 5 shows graphical representations of the evolution of the ratio between the resistance of a high frequency electric stator conductor and the resistance of a low frequency electric stator conductor as a function of the radial dimension of an active portion of a stator conductor respectively for a rotor with 3 and 5 pairs of poles.
• FIG. 6 represents the evolution of the total axial height of the rotating electrical machine as a function of the number of pole pairs of the rotor.
• FIG. 2 shows a rotating electrical machine 10 comprising a stator
• stator 1 1 polyphase surrounding a rotor 12 mounted on a shaft 13 extending along an axis X corresponding to the axis of the machine.
• the stator 1 1 surrounds the rotor
• stator January 1 is mounted in a housing 14 provided with a front bearing 15 and a rear bearing 16 bearing rotatably the tree 13.
• This electric machine 10 may be intended to be coupled to a gearbox belonging to a motor vehicle traction chain.
• the electric machine 10 may be coupled to a crankshaft of the vehicle or directly to the wheel drive chain of the vehicle.
• the machine 10 may be coupled to a portion of the vehicle by a pinion 17 as shown in Figure 2.
• the machine 10 may be coupled to a portion of the vehicle by a pulley or other coupling means.
• the machine 10 is able to operate in an alternator mode to supply, in particular, energy to the battery and to the on-board vehicle network, and in a motor mode, not only to start the engine of the vehicle, but also to participate in pulling the vehicle alone or in combination with the engine.
• the electric machine 10 may be implanted on a motor vehicle axle, in particular a rear axle.
• the electric machine 10 takes the form of an electric motor or a non-reversible generator.
• the power of the electric machine 10 is advantageously between 8kW and 30kW.
• the rotor 12 comprises a body 19 in the form of a package of sheets.
• Permanent magnets 20 may be implanted inside cavities 21 in a V-shaped configuration, as shown in FIG. 4, or may be implanted radially inside the pack of sheets, the lateral faces two consecutive magnets can be be the same polarity, as shown in Figure 3.
• the rotor 12 is then the flux concentration type.
• the permanent magnets 20 extend ortho-radially inside the cavities 21 of the body 19.
• the magnets 20 may be of rare earth or ferrite depending on the applications and the desired power of the machine 10.
• the stator 1 1 comprises a body 24 constituted by a bundle of sheets and an electric coil 25.
• the body 24 is formed by a stack of sheets of independent sheets from each other and held in pack form by means of a suitable fastening system.
• the body 24 is provided with teeth 28 delimiting two by two notches 30 for mounting the stator winding 25.
• two successive notches 30 are separated from each other by a tooth 28.
• an outer diameter L1 of the stator body 24 is between 80 and 180mm.
• the outside diameter L 1 of the stator body 24 is selected from one of the following values: 80, 90, 100, 1 10, 153, 161 and 180 mm.
• the coil 25 comprises a set of phase windings 26 passing through the notches 30 and forming bunches 33 projecting on either side of the stator body 24, as shown in FIGS. 2 and 3.
• the outputs of the phase windings 26 are connected to an inverter 34 which can also operate as a rectifier bridge.
• the inverter 34 comprises power modules provided with power switching elements, such as MOS transistors, connected to the phase outputs.
• Each phase winding 26 may be formed from a plurality of conductors 35 constituted by pins 37. These pins 37 may have a U-shaped whose ends of the branches are interconnected for example by welding. Alternatively, each phase winding 26 is formed from a continuous conductive wire wound inside the stator January 1 in the notches 30 to form one or more turns. In all cases, there are active portions 40 of a conductor 35 located inside the notches 30 and connecting portions 41 interconnecting two active portions 40 adjacent. The active portions 40 thus correspond to the portions of the conductors 35 extending axially inside the notches 30, while the connecting portions 41 extend circumferentially inside the buns 33 to interconnect the active portions 40.
• the conductors 35 may for example be made of a material based on enamelled copper.
• the phase windings 26 are each associated with a series of notches 30, so that each notch 30 receives several times the conductors 35 of the same phase.
• the stator January 1 comprises two three-phase systems, preferably independent, A1, B1, C1 and A2, B2, C2 each formed by three phase windings 26, as shown in Figure 4. This ensures the compactness of the inverter 34 by facilitating the arrangement of the power modules of the inverter 34 in a cylinder located at the rear of the machine for the integrated systems (see Figure 2) or in a substantially parallelepipedic space on the side of the machine 10.
• Each three-phase system A1, B1, C1; A2, B2, C2 is coupled in a triangle to optimize the compactness of the electrical machine 10.
• the double-triangle coupling makes it possible to avoid the integration of the neutral bars into the wound stator 1 1 which are relatively bulky.
• Each three-phase system A1, B1, C1; A2, B2, C2 is electrically connected to a module independent of the inverter 34.
• Each independent module comprises power elements and a control module dedicated to the corresponding three-phase system.
• the two independent modules are housed in the same housing of the inverter 34 covering the rear bearing.
• the inverter 34 is preferably connected to a DC bus having a voltage of between 30 and 60 volts.
• the first notch comprises the phase A1
• the second notch comprises the phase A2
• the third notch comprises the phase B1
• the fourth notch comprises the phase B2
• the fifth notch comprises the phase C1
• the sixth notch includes phase C2.
• another phase configuration can be envisaged.
• the conductors 35 advantageously have a substantially rectangular section at least in their active portion 40 and are aligned radially with respect to each other within the corresponding notch 30.
• Such a winding configuration stored with conductors 35 of substantially rectangular section reduces the height of the buns 33 and promotes the compactness of the machine with respect to a random winding round wire.
• the conductive son may be stamped only in the active portions 40 and have a round section in the connecting portions 41.
• the substantially rectangular section of the active portions 40 may have rounded corners so as not to damage the enamel.
• the conductors 35 may have a substantially square section.
• the number of conductors 35 inside each notch 30 is advantageously strictly greater than two in order to have a degree of freedom in terms of choice of the number of turns per phase winding 26.
• the number of conductors 35 by notch is even. It is here equal to 4 but could alternatively be different, and especially equal to 6, 8 or 10.
• the conductors 35 are subjected to film and proximity effects which lead to make the current density in the conductor 35 non-uniform. This results in an increase in the apparent resistance of the It is customary to quantify this increase in resistance by a ratio between the high frequency resistance AC and the DC resistance of the same conductor 35 at a very low frequency of a few Hertz.
• the main factor influencing the resistance AC is the radial length L2 of the conductor 35 inside the notch 30, as well as the electric frequency fe linked to the polarity of the rotor 12 for the same speed of rotation.
• FIG. 5 represents, for an electrical machine 10 having a stator diameter L1 of the order of 160 mm and a rotational speed of 20000 revolutions / min, the evolution of the ratio between the resistance AC of a stator conductor at high frequency and the DC resistance of this low frequency stator conductor as a function of the radial length L2 of the active portion 40 of a conductor 35 respectively for a rotor with 3 pole pairs (see curve C5) and 5 pairs of poles (see curve C6).
• the maximum radial length L2 of the conductor 35 is 3.6 mm for a machine with five pairs of poles. Such a value guarantees a suitable behavior for a machine with three pairs of poles whose AC / DC ratio is generally lower than that of the machine with five pairs of poles.
• the orthoradial length L3 of an active portion 40 is greater than or equal to 1 .4 mm. This length L3 has little effect on the AC resistance of the conductors 35. Indeed, as can be seen in FIG.
• FIG. 6 represents the evolution of the total axial height L4 of the stator 1 1 of the electric machine 10 (see FIG. 2) as a function of the number of pairs of poles p of the rotor 12.
• axial height is meant the distance between the two ends of the front and rear buns 33.
• the notches traversed by the same phase winding are further apart from each other and the portions of the conductors forming the buns must therefore be larger.
• a polarity of more than five pairs of poles generates too many losses.
• the optimum polarity is between 3 and 5 pairs of poles, that is to say that the rotor 12 may comprise 3 or 4 or 5 pairs of poles.
• the rotating electrical machine 10 may comprise a coolant circuit having an inlet and a liquid cooling outlet for circulating the liquid in a chamber 44 arranged at the outer periphery of the stator January 1, as shown in FIG. electrical 10 may be cooled by water or oil. In an alternative embodiment, the machine can be cooled by air, for example by means of a fan.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Windings For Motors And Generators (AREA)
• Permanent Magnet Type Synchronous Machine (AREA)
• Iron Core Of Rotating Electric Machines (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=59070835

Family Applications (1)

Country Status (7)

Families Citing this family (5)

Family Cites Families (10)

• 2017
  • 2017-03-29 FR FR1752610A patent/FR3064834B1/fr active Active
• 2018
  • 2018-03-22 JP JP2019553213A patent/JP2020512806A/ja active Pending
  • 2018-03-22 EP EP18712219.7A patent/EP3602755A1/de not_active Withdrawn
  • 2018-03-22 US US16/498,948 patent/US20210111614A1/en not_active Abandoned
  • 2018-03-22 KR KR1020197028576A patent/KR102362548B1/ko active IP Right Grant
  • 2018-03-22 WO PCT/EP2018/057345 patent/WO2018177896A1/fr unknown
  • 2018-03-22 CN CN201880019390.3A patent/CN110462996A/zh active Pending

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