Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
  • G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
  • G01R15/20—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
  • G01R15/202—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices using Hall-effect devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
  • G01R35/005—Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
  • G01R31/382—Arrangements for monitoring battery or accumulator variables, e.g. SoC
  • G01R31/3828—Arrangements for monitoring battery or accumulator variables, e.g. SoC using current integration
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/0023—Electronic aspects, e.g. circuits for stimulation, evaluation, control; Treating the measured signals; calibration
  • G01R33/0029—Treating the measured signals, e.g. removing offset or noise

Definitions

• the invention relates to the technical field of electric current sensors and in particular that of current sensors using the Hall effect.
• the invention is particularly applicable to measuring the current of an electric battery, for example equipping motor vehicles.
• a method of compensating for errors due to the magnetic hysteresis of the sensors is also known.
• this method requires an active loop of current.
• Sensors using this method so-called closed-loop sensors then have a higher consumption and a higher cost than open-loop sensors.
• patent application EP 0779971 a hysteresis compensation method which provides for the suppression of value jumps during dynamic loading of a force sensor.
• patent application US2007038401 a hysteresis compensation method that provides a compensation of magnetic fields external to the sensor and measurable.
• the subject of the invention is thus a system for measuring electric current supplied by an electric battery, in particular a battery fitted to a motor vehicle, comprising:
• a device for compensation of measurement errors of the sensor comprising means for applying the measured current of an operation approaching the inverse of an operator characterizing the magnetic hysteresis of the sensor.
• the error compensation system further comprises a subtracter for deriving the offset error of the Hall effect current sensor from the measured current followed by a multiplier to compensate for the gain error of the current sensor. Hall effect.
• the operator is a Play operator and the means of application on the measured current of an operation comprise:
• a subtracter for determining the difference between the delayed measured intensity and the measured intensity; means for extracting a positive or negative sign from the difference between the delayed measured intensity and the measured intensity;
• the operation to approach the inverse of the operator Play is very simple. This is particularly interesting since it allows a real time correction of the measured intensity. Thus, for example, in the case of an application to a measurement of autonomy, it is possible to take into account the corrected intensity for a continuous display of the autonomy.
• the invention also relates to a method for measuring an electric current supplied by an electric battery, in particular a battery equipping a motor vehicle, comprising:
• a step of compensating measurement errors of the sensor comprising an application on the measured current of an operation approaching the inverse of an operator characterizing the magnetic hysteresis of the sensor.
• the error compensation step further comprises a step of corrections of the offset and gain errors of the Hall effect sensor.
• the operator is a Play operator according to which the hysteresis cycle of the actual intensity expressed as a function of the measured intensity comprises two parallel lines and the method comprises a preliminary step of characterization of the Hall effect sensor. comprising:
• the operator is a Play operator and said operation comprises:
• the system is connected for example to integrators.
• integrators This use is advantageous because in the particular case of a vehicle with electric propulsion, the current profile is not symmetrical (the current goes mainly from the battery to the electric motor) and the errors due to the magnetic hysteresis are particularly detrimental to, for example, the measurement of autonomy.
• the current profile is symmetrical (while driving the current between and out of the battery) which allows the compensation of errors due to the magnetic hysteresis for the measurement of autonomy.
• FIG. 2 schematically illustrates the operating principle of a Play operator
• FIG. 3 illustrates a transformation means according to one embodiment of the invention.
• FIG. 4 illustrates a transformation means according to another embodiment of the invention.
• Figure 1 illustrates a Hall effect sensor 1 represented by a ring crossed by the actual intensity IREEL. This sensor is connected to the output of a battery and measures from the actual IREEL intensity an IMES measured intensity.
• the IMES measurement shows measurement errors, namely offset and gain errors and errors due to the magnetic hysteresis of the Hall effect sensor. Linearity errors are usually already accounted for by the commercially available effect transducer.
• the system is equipped with a measurement error compensation device 2 connected to the output of the Hall sensor which compensates for measurement errors.
• the corrected intensity ICORR then has fewer measurement errors than the IMES intensity.
• the sensor 1 can be schematized by a blo c 3 followed by a blo c 4 representing the addition of measurement errors of the sensor 1.
• Block 3 corresponds to offset and gain errors.
• the blo c 4 corresponds to the errors due to the magnetic hysteresis.
• the measurement error compensation device 2 can be schematized by a block 5 followed by a block 6 representing the compensation of the measurement errors of the sensor 1.
• Block 5 corresponds to corrections of offset and gain errors
• block 6 corresponds to corrections of errors due to magnetic hysteresis.
• the block 5 will add to each IMES measurement a first constant K1 and will multiply the result by a second constant K2.
• the constant K1 is determined, for example, by averaging a plurality of measured current values IMES for a controlled true current IREEL having a zero value.
• the constant Kl therefore corresponds to the offset error of the Hall effect current sensor.
• the constant K2 is determined, for example, by averaging the ratio between the actual controlled intensity values IREEL cont and several corresponding measured IMES values.
• the constant K2 therefore corresponds to the inverse of the gain error of the sensor.
• Block 6 comprises means of application to the measured current of an operation approaching the inverse of an operator characterizing the magnetic hysteresis of the sensor 1.
• a prior characterization of the hysteresis by a operator for example a Play operator or a Preisach operator
• the block 6 will apply to the output intensity of the block 5 an operation approaching the inverse of this operator.
• inversion of the operator Preisach consumes many resources since it requires a variable for each sampling step. That is to say for example in the case of a current amplitude of + 1-6 A with a resolution of 0.5 mA, not less than 1200 variables. In addition to the large number of variables involved, inversion is performed by iterative calculation at each sampling step.
• the abscissa represents the actual current IREEL
• the ordinate axis represents the measured current IMES.
• the value of the measured current is represented respectively by the rising line D 1 or the descending line D 2.
• the slope of each of the straight lines D 1 or D 2 is 1.
• An example of a characterization of an effect sensor in the case of a Play operator as illustrated in FIG. 2 comprises:
• FIG. 3 shows a particular embodiment of the busses 5 and 6 of the device for compensating measurement errors of the sensor 1.
• the block 5 comprises a subtracter S1 to deduce the offset error of the Hall effect current sensor K1 of the measured current. IMES followed by a multiplier M1 to compensate for the gain error of the Hall effect current sensor 1 by multiplying the result of the subtraction by the inverse of the gain of the sensor, K2.
• Block 6 includes derivative sign determination means including delay applying means RET and subtracter S2 to determine the difference between the retarded intensity and the undelayed intensity.
• Block 6 also comprises extraction means EXT of the positive or negative sign of the derivative and allocation means, for example a multiplier M2, for assigning the sign extracted to the constant K3 corresponding to the width of the hysteresis cycle;
• Block 6 finally comprises a subtracter S3 for subtracting from the measured intensity IMES the constant K3 on which is assigned the sign: +/- K3.
• the corrected intensity is:
• FIG. 4 illustrates the steps of a method of measuring the intensity according to the invention using the Hall effect sensor 1.
• a first step 10 the current IREEL is measured by the sensor 1. The measurement obtained is IMES. Then, in a step 111, the offset and gain errors in the measured current IMES relative to the actual current IREEL are compensated. This step is carried out by block 5. Finally, in a step 112, the errors in the measured current IMES due to the magnetic hysteresis are compensated. This step is performed by block 6.
• the measured current IMES is corrected and has the value ICORR.

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Measurement Of Current Or Voltage (AREA)
• Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=47115952

Family Applications (1)

Country Status (5)

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Citations (1)

Family Cites Families (17)

• 2011
  • 2011-11-10 FR FR1160260A patent/FR2982674B1/fr active Active
• 2012
  • 2012-10-30 EP EP12780191.8A patent/EP2776852A1/de not_active Withdrawn
  • 2012-10-30 US US14/357,362 patent/US20140320142A1/en not_active Abandoned
  • 2012-10-30 WO PCT/EP2012/071469 patent/WO2013068278A1/fr not_active Ceased
  • 2012-10-30 CN CN201280060634.5A patent/CN103975246A/zh active Pending

Patent Citations (1)

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