Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
  • H02K29/06—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
  • H02K29/06—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices
  • H02K29/08—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices using magnetic effect devices, e.g. Hall-plates, magneto-resistors
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
  • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
  • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
  • G01D5/244—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains
  • G01D5/24409—Interpolation using memories
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
  • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
  • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
  • G01D5/244—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains
  • G01D5/245—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains using a variable number of pulses in a train
  • G01D5/2451—Incremental encoders
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
  • G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
  • G01P3/42—Devices characterised by the use of electric or magnetic means
  • G01P3/44—Devices characterised by the use of electric or magnetic means for measuring angular speed
  • G01P3/48—Devices characterised by the use of electric or magnetic means for measuring angular speed by measuring frequency of generated current or voltage
  • G01P3/481—Devices characterised by the use of electric or magnetic means for measuring angular speed by measuring frequency of generated current or voltage of pulse signals
  • G01P3/487—Devices characterised by the use of electric or magnetic means for measuring angular speed by measuring frequency of generated current or voltage of pulse signals delivered by rotating magnets
• • 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
  • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
  • H02P6/14—Electronic commutators
  • H02P6/16—Circuit arrangements for detecting position

Definitions

• the present invention relates to a device for determining the position of a rotor of a rotating electrical machine comprising a stator.
• the invention finds a particularly advantageous application in the field of reversible machines, or alternator-starters, used in the automotive industry, both in alternator mode in engine mode at startup or in help with takeoff ("boost”) to from 500 rpm
• a reversible machine comprises an alternator comprising:
• a rotor comprising an inductor conventionally associated with two slip rings and two brushes through which an excitation current is fed;
• a polyphase stator carrying a plurality of coils or windings which are connected in a star or in a triangle in the most frequent case of a three-phase structure and which deliver to a rectifier bridge, in alternating operation, a converted electrical power.
• the machine has two bearings, a front and a rear, to attach it to the engine and to fix the stator.
• the stator surrounds the rotor.
• the rotor is carried by a shaft supported by the front and rear bearings.
• the brushes are connected to an alternator regulator to maintain the voltage of the alternator at a desired voltage for a battery depending on whether it is empty or charging.
• the alternator makes it possible to transform a rotational movement of the rotor, driven by the engine of the vehicle, into an electric current induced in the stator windings.
• the alternator can also be reversible and compose an electric motor, or rotating electrical machine, for driving in rotation, via the rotor shaft, the engine of the vehicle.
• This reversible alternator is called alternator-starter or alterno-starter. It makes it possible to transform mechanical energy into electrical energy and vice versa.
• alternator mode Palterno-starter loads including the vehicle battery and consumers while in starter mode the alternator-starter drives the engine also called internal combustion engine, the motor vehicle for startup.
• the stator In reversible machines of the automotive industry, for example, operating in motor or starter modes, the stator must be driven in order to apply at all times to the rotor the necessary torque both for moving it and for it. print the rotation required for engine operation.
• this torque to be applied to the rotor, and therefore the current to be supplied to the phases of the stator is a sinusoidal function of the position, indicated by an angle ⁇ , of the rotor relative to the stator, hence the need to determine this position. precisely.
• resolver a device known as the resolver disposed at the end of the rotor shaft of the machine.
• a resolver is described in US Patent 2002/0063491 A1. It itself comprises a stator and a rotor which are respectively fixed relative to the stator and the rotor of the machine. Said resolver measures the magnetic field from its own rotor. This magnetic field being fixed relative to said rotor which is itself fixed relative to the rotor of the machine, is representative of the position of the rotor itself of the machine.
• Resolvers are indeed expensive and their implementation to make them operational is complex because of the coupling to be performed between such a resolver and the machine itself requiring the presence of an electronic calculation component to provide a correct position of the rotor of the machine from the coupling parameters.
• the technical problem to be solved by the object of the present invention is to propose a device for determining the position of a rotor of a rotating electrical machine comprising a stator, which would make it possible to obtain the precise position sought while being cheap, simple to implement and insensitive to magnetic disturbances.
• the solution to the technical problem posed consists, according to the present invention, in that said device comprises a plurality of magnetic field sensors fixed with respect to the stator and able to deliver first signals representative of a rotating magnetic field detected by said sensors, and means for processing said first signals by an operator capable of providing second signals depending on said position.
• the first signals are three-phase electrical signals and the second signals are two-phase electrical signals.
• said operator is represented by a projection matrix of a multi-phase marker in a two-phase marker.
• the projection matrix is a Concordia matrix.
• the projection matrix is a Clark matrix.
• the device according to the invention leads to an accurate determination of the position of the rotor, in particular because of its independence vis-à-vis many parameters and its insensitivity to various disturbances and parasitic phenomena.
• several features of the determination device, object of the invention contribute to reduce the cost and simplify its implementation.
• the invention provides that said sensors are Hall effect sensors.
• the plurality of sensors consists of three sensors electrically phase shifted by 120 °.
• the plurality of sensors consists of two sensors electrically phase shifted by 90 °.
• the rotating magnetic field necessary for the operation of the device according to the invention can be obtained according to two different modes of production.
• said magnetic field is the magnetic field created by the rotor
• said magnetic field is created by a magnetized target linked to the rotor shaft.
• FIG. 1 is an axial sectional view of a rotary electrical machine comprising a position determining device according to the invention
• FIG. 2 is a view according to arrow 2 of the rotary electric machine of FIG. 1
• FIG. 3 is a perspective view of a sensor holder of the device for determining the invention of FIG. 1
• FIG. 4 is a diagram of a rotating electrical machine of FIG. 1 having an embodiment of a position determining device according to the invention
• FIG. 5 is a diagram of the embodiment of the position determining device of FIG. 4
• Fig. 6 is a diagram showing the variations of the sensor output signals of the device of FIG. 4
• Fig. 7 is a diagram of a signal processing chain by the position determining device of FIG. 4.
• FIG. 1 such a rotating electrical machine comprising, in a first embodiment:
• stator 8 provided here with three windings for definition of three phases 10 (shown in FIG 2), the stator also comprising poles,
• a rotor 4 having two pole wheels with claws 41, 42 fixed on a shaft 3, the claws also being called teeth 143.
• the teeth of the pole wheels are interlocked with each other.
• the teeth of one of the pole wheels define north poles, while the teeth of the other pole wheel define south poles.
• the rotor is thus magnetized. There is then the creation of pairs of north-south poles,
• the target is magnetic 50 and comprises an alternation of south poles and north poles regularly distributed, defined by permanent magnets for example.
• the target 50 comprises a number of pairs of magnetic poles identical to that of the rotor 4.
• Magnetic field sensors 52 the sensors being three in the case of a three-phase machine in the example taken, - a sensor holder 53 for carrying the three sensors 52, said sensor holder being fixed on the bottom of the rear bearing 14, and
• means MC for processing first signals from the sensors 52 by an operator [M].
• the magnetic field sensors 52 are implanted facing the target 50, and the sensor holder 53 is fixed on the face of the rear bearing 14 facing away from the target 50, as illustrated in FIG. Fig. 2, FIG. 2 being a view along the arrow 2 of FIG. 1 without the cover 17.
• the sensors 52 are implanted radially facing the target 50, perpendicular to the shaft 3 of the rotor 4, with definition of a gap between the sensors and the target so that the reading is radial, as illustrated in FIG. 1.
• the sensors 52 are located axially facing the target 50, in the axis of the shaft 3 of the rotor 4, with definition of an air gap between the sensors and the target so that the reading is axial.
• the magnetic field sensors 52 are located facing the rotor 4, and the sensor holder 53 is fixed on the face of the front bearing 13.
• the sensors 52 are located radially on the side of the rotor 50, perpendicular to the shaft 3 of the rotor 4 so that the reading is radial. In a second variant embodiment, the sensors 52 are located axially on the top of the rotor 4, in the axis of the shaft 3 of the rotor 4, so that the reading is axial.
• the sensors are overmolded on the sensor holder 53, the latter preferably being made of plastic. This allows the sensor assembly, sensor holder to be waterproof and thus to be less sensitive to salt spray and dust.
• Fig. 3 shows an exemplary embodiment of a sensor holder 53 for a radial reading.
• Said sensor holder 53 comprises in particular:
• a sector 55 making it possible to receive the sensors 52, said sensors being situated at the inner periphery of said sector in the example of radial reading, and
• Fig. 4 is a diagram of elements of the rotating electrical machine 1 comprising an embodiment of the device for determining the position of the rotor according to the invention.
• Fig. 5 is another schematization of the device for determining the position ⁇ (t) of the rotor 4. More precisely, by the expression rotor position is meant the position of a direction Oy related to the rotational movement of the rotor taken with respect to a fixed direction Ox linked to the sensor holder 53 and thus fixed with respect to the stator 8.
• the set of sensors consists of three sensors 52u, 52v, 52w Hall effect phase shifted between them 120 ° electrical.
• another arrangement of sensors may be provided, for example two Hall effect sensors which are 90 ° apart from each other or more than three sensors, for example five sensors 72 ° apart from each other.
• the interest of Hall effect sensors is to measure a magnetic field and to transpose this measurement into a representative signal of said magnetic field of magnitude equivalent to a voltage, frequency, current, digital ....
• the sensors 52u, 52v, 52w are intended to provide first s u , s v and s w signals representative of a magnetic field detected at each sensor and created by the movement of the rotor in the stator.
• the three sensors measure at the same time said magnetic field at different locations. This magnetic field is a sum of different magnetic fields from different sources.
• the magnetic field is created by said target 50 plus, if necessary, a leakage field created by the pole wheels 41, 42 of the rotor 4 itself.
• the first signals are three-phase electrical signals.
• the first signals may also be digital signals representative of the magnetic field.
• Fig. 6 illustrates the variations over time of the first signals s u , s v and s w delivered by the three sensors 52u, 52v and 52w in the case of three-phase electrical signals.
• These first ones have a continuous component s O ff S and offset including, where appropriate, the magnetic disturbances created by the rotor 4, and a substantially sinusoidal component reproducing the variations of the magnetic field detected by each sensor.
• Such an offset can have a value of 2.5V.
• the sinusoidal component depends in particular on the position of the sensor with respect to the rotor 4 (in the case of the second mode of realization) or to the target 50 (case of the first embodiment), this position being determined by the distance R illustrated in FIG. 5. More precisely, the component varies according to 1 / R 2 . Thus, the closer a sensor 52 is to the rotor 4 (case of the second embodiment) or the target 50 (case of the first embodiment), the more the variations of the sinusoidal component are important in amplitude.
• the maximum of the signals is reached when a sensor is opposite a north pole of the rotor 4 (case of the second embodiment) or of the target 50 (case of the first embodiment). The signals are on the contrary minimum each time a sensor is facing a south pole of the rotor 4 (case of the second embodiment) or the target 50 (case of the first embodiment).
• the set of signals s u , v and s w depends directly on the position ⁇ (t) of the desired rotor because the frequency of said signals depends on the rotation frequency of the rotor 4 (case of the second embodiment) and its number of poles or the number of poles of the target 50 (case of the first embodiment).
• the frequency of the first signals from the sensors 52 is equal to that of the rotation of the rotor 4 multiplied by the number of pairs of poles of the rotor 4 (case of the second embodiment) or the target 50 (case of the first embodiment realization).
• Fig. 7 gives a diagram of a processing chain for precisely extracting the position ⁇ (t) of the signals s u , s v and s w .
• the signal processing means MC which is preferably a microcontroller located in the electronic part which controls the machine, which electronic part is in a known manner in an outer casing or integrated with said machine.
• the matrix M is a projection matrix of a multiphase reference to a two-phase reference, thus transforming multiphase signals into two two-phase signals.
• the multiphase mark is a three-phase mark.
• the third output component h is not used in the context of the invention. It is composed of an average of the components s O ffset offset and a signal whose amplitude is a function of an error of phase shift between the signals provided by the Hall effect sensors where said sensors are not well mounted so that the first signals are not quite out of phase 120 ° for example.
• the projection matrix M is an inverse matrix of a matrix known as Concordia matrix C.
• the projection matrix M is an inverse matrix of a matrix known as the Clark C matrix.
• coefficients of these projection matrices are constant but are a function of conventions such as the direction of rotation of three-phase currents, the intensity of its currents .... Also, one can have a different normalization factor.
• the argument of an angle ⁇ (t) is calculated from the two second signals sin ⁇ (t) and cos ⁇ (t), the angle ⁇ (t) representing the position of the rotor 4.
• one of the advantages of the treatment illustrated in FIG. 7 is that it is independent of parameters such as the amplitude of the first signals s u , s v and s w or else such as offsets OffS and, which makes the result of the determination of the position ⁇ (t) insensitive to magnetic disturbances, in accordance with an object of the invention.
• the device according to the invention which has just been described with reference to FIGS. 1 to 7 is also insensitive to common-mode noise that could be applied to the first signals s u , s v and s w output magnetic field sensors 52u, 52v and 52w.
• the common mode noise is due to reference differences between a first signal measured by a sensor and referenced with respect to the mass of said sensor and the first signal received by the microcontroller MC and referenced with respect to the mass of said microcontroller MC. It happens that the two references are shifted relative to each other, this shift introducing an error called common mode parasite.
• the position determination device can also be implemented in all electrical machines where the position of the rotor relative to the stator must be known precisely.
• the invention is thus applicable to all types of electrical machines and for different operations.
• the invention can indeed be applied to machines operating as an alternator alone, as a single motor or as an alternator-starter, and asynchronous machines, synchronous claw machines with or without interpolar magnets or still machines with permanent magnet rotor.

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Control Of Motors That Do Not Use Commutators (AREA)
• Transmission And Conversion Of Sensor Element Output (AREA)
• Electric Propulsion And Braking For Vehicles (AREA)
• Hybrid Electric Vehicles (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34946707

Family Applications (1)

Country Status (11)

Families Citing this family (12)

Citations (1)

Family Cites Families (11)

• 2004
  • 2004-06-30 FR FR0407262A patent/FR2872644B1/fr not_active Expired - Fee Related
• 2005
  • 2005-06-30 KR KR1020067027748A patent/KR20070047250A/ko not_active Application Discontinuation
  • 2005-06-30 JP JP2007518646A patent/JP2008504799A/ja active Pending
  • 2005-06-30 EP EP05779717A patent/EP1776593A2/de not_active Withdrawn
  • 2005-06-30 US US11/570,930 patent/US7944168B2/en active Active
  • 2005-06-30 RU RU2007103362/28A patent/RU2007103362A/ru not_active Application Discontinuation
  • 2005-06-30 CN CN2005800213844A patent/CN101076733B/zh active Active
  • 2005-06-30 WO PCT/FR2005/001663 patent/WO2006010864A2/fr active Application Filing
  • 2005-06-30 BR BRPI0512289-9A patent/BRPI0512289A/pt not_active Application Discontinuation
  • 2005-06-30 MX MXPA06014538A patent/MXPA06014538A/es not_active Application Discontinuation
  • 2005-06-30 CA CA002566909A patent/CA2566909A1/fr not_active Abandoned

Patent Citations (1)

Also Published As

Similar Documents

Legal Events