WO2013124571A1 - Procede et systeme d'estimation de la resistance d'isolement entre une batterie et une masse electrique - Google Patents
Procede et systeme d'estimation de la resistance d'isolement entre une batterie et une masse electrique Download PDFInfo
- Publication number
- WO2013124571A1 WO2013124571A1 PCT/FR2013/050320 FR2013050320W WO2013124571A1 WO 2013124571 A1 WO2013124571 A1 WO 2013124571A1 FR 2013050320 W FR2013050320 W FR 2013050320W WO 2013124571 A1 WO2013124571 A1 WO 2013124571A1
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- WIPO (PCT)
- Prior art keywords
- output voltage
- parameters
- determination
- capacitance
- voltage
- Prior art date
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Classifications
-
- 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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/52—Testing for short-circuits, leakage current or ground faults
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/025—Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
-
- 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
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
Definitions
- the technical field of the invention is the measurement of electric dipoles and more particularly the measurement of the insulation resistance within, for example, a vehicle comprising a high-voltage battery.
- the insulation resistance between a point of the battery connected to the high voltage (for example: the positive or negative terminal of the battery or a connector between the cells of the battery).
- the battery, or a bus high voltage) and the electric mass of the vehicle is an essential security component.
- the insulation resistance which makes it possible to prevent any electric shock of the passengers of the vehicle or of the living beings coming into contact with the vehicle.
- a double fault can create a short circuit. More generally, a double fault can be dangerous if a person touches the body of the vehicle, even if there is no short circuit. For example, in the case where the positive terminal is connected to the box and the negative terminal is connected to the ground, the user with the feet to the earth touching the box is then in direct contact with the two terminals positive and negative drums.
- patent application JP2003-250201 proposes a circuit for measuring the insulation resistance.
- the measuring circuit comprises a capacitance whose value is assumed to be known for measuring the insulation resistance. That being the case, Ordinary capacities generally have a value which varies according to the temperature, the voltage at their terminals or their aging. For this assumption to be valid and the measurement to be reliable, it is therefore necessary to use a capacity that is stable in value throughout its aging. This usually implies an extra cost compared to an ordinary capacity.
- An object of the invention is therefore to propose a method for measuring the insulation resistance intended to solve the defects mentioned above.
- the object of the invention is therefore to provide a method for estimating the insulation resistance between a terminal of a battery and an electrical ground, comprising:
- said measuring circuit comprising a resistor of known value and a capacitance
- the method further comprises:
- the capacitance of the measurement circuit is also determined from the parameters of the differential equation or of said complex impedance.
- the input signal applied is a square signal.
- the square signal has the advantage of being easy to generate and to contain many harmonics whose relative amplitudes are known.
- the determination of the parameters of the differential equation comprises:
- said measurement of the output voltage is carried out at several times and the determination of the parameters of said second equation uses a least squares method with the values at said several instants of the measured output voltage. and the input voltage.
- the method further comprises a frequency analysis of the output voltage measured at at least one frequency so as to determine for at least this frequency the value of the complex impedance, said application of a input signal to the input terminal of the measuring circuit, said output voltage measurement, said frequency analysis and said determination of the value of the complex impedance being performed by a network analyzer.
- the functionality of the network analyzer can be reduced since it is sufficient to characterize a complex impedance in transmission over a reduced frequency range and with a measurement accuracy of the order of ten percent.
- the method furthermore comprises a digitization of the measured output voltage and the frequency analysis is carried out by means of a Fourier transform or a Goertzel filtering of the voltage of digitized output.
- the frequency analysis can then be performed according to a conventional method using the Fourier transform.
- the frequency analysis can use Goertzel filtering. Goertzel filtering is faster than the Fourier transform since it does not require computation of the whole spectrum but is limited to the calculation of a spectrum line of the Fourier transform.
- the frequency analysis is performed at a fundamental frequency of the input voltage and / or at two harmonics of the input voltage.
- a triple determination makes it possible to choose the right measure among the three, by a voting system for example. It also allows rejection of measurements if there is too much dispersion between the three determinations.
- the invention also relates to a system for estimating the insulation resistance between a terminal of a battery and an electric ground, comprising a measurement circuit which comprises an output terminal, an input terminal, a resistor of known value and a capacitance, the output terminal being connected to a terminal of the battery and the input terminal being adapted to receive a known input signal having an input voltage.
- the system further comprises:
- FIG. 1 illustrates a block diagram of a measuring circuit according to one embodiment of the invention
- FIG. 2 illustrates a measurement method according to a first embodiment of the invention
- FIG. 3 illustrates a measuring method according to a second embodiment of the invention.
- FIG. 1 shows a measurement circuit CM comprising a resistor R and a capacitance CE, connected to a terminal of a high voltage battery Batt equipping an electric vehicle.
- the battery Batt is, for example, a battery for propulsion or traction of the electric vehicle.
- Resistance Resol is the resistance between a terminal or any other point of the battery Batt and the electric mass M of the vehicle.
- the measuring circuit CM comprises an input terminal for receiving an input voltage Ue and an output terminal connected to one of the terminals of the battery Batt.
- the resistance R of the measuring circuit CM is of known value and the coupling capacitance CE of the measuring circuit is of a value which will be determined.
- FIG. 2 shows, in a first embodiment, a measurement method for measuring the output voltage and deriving the values of Risol and CE.
- the method comprises:
- the input signal is a square wave voltage of 0.5 Hz frequency, which has a high value of 5 volts and a low value of 0 volts.
- step 2 a second measurement step (step 2) of the output voltage Us
- step 3 a third step (step 3) of determining parameters of a differential equation between the input voltage Ue and the output voltage Us.
- This differential equation is obtained from a transfer function, for example.
- Equation 1 Equation 1
- step 3 of the method comprises:
- step 3A a step of filtering (step 3A) of the differential equation (equation 1) by a filter F1 of the first order of the form:
- parameter ⁇ is a setting parameter of the PMF method. It can for example be set according to the value of the bandwidth of the system to be identified.
- the use of the filter F1 makes it possible to avoid the difficulty represented by the calculation of the direct time derivatives of the input and output signals ù s (t) and ù e (t). Indeed, the calculation of these derivatives is made difficult by the presence in the real case of noise affecting the signals u s (t) and u e (t).
- the method also includes:
- x (t) is the signal Us (t) or Ue (t).
- the method comprises a step 3D during which the parameters of said second equation are determined.
- the temporal parameter t is varied from ti to dans in equation 2.
- a sampling period of 10 ms and a signal Ue ( t) 0.5 Hz square predict a variation of the time parameter so as to cover a period of the signal Ue (t).
- the temporal parameter could also be varied over a larger interval to obtain a better estimate of the parameters of equation 2.
- the vector ⁇ of the parameters to be determined can therefore be calculated such that:
- the method comprises a fourth step (step 4) of determining the insulation resistance Risol and the capacitance CE from said parameters. For this we use the change of variables of equation 1:
- R isol R ⁇ " ⁇ ⁇
- the measurement method presented thus makes it possible to estimate the value of the insulation resistance Risol and the capacitor CM at the end of a single embodiment of the illustrated process.
- the calculation steps 3A, 3B, 3C, 3D and 4 are for example implemented by one or more calculation blocks integrated in a digital processing unit.
- the calculation blocks implementing steps 3A, 3B, 3C, 3D and 4 can be implemented in the form of software modules or for some of them in the form of logic circuits.
- the complex impedance Z in transmission is connected to the output voltage Us by the following impedance equation:
- Us and i are respectively the output voltage Us and an intensity i which enters on the exponential write dipole.
- a network analyzer is used.
- the network analyzer is connected to the input terminal of the measuring circuit CM to send an input signal whose amplitude and frequency are known having a voltage Ue.
- the network analyzer will also measure the output voltage Us across the dipole.
- a digital analog converter is used between the network analyzer and the measuring circuit. The digital analog converter will sample the voltage Us which will then be transmitted in sampled form to the network analyzer.
- FIG. 3 shows, according to the second embodiment, the measurement method for determining the value of the insulation resistance Riso 1 and the capacitance CE of the measurement circuit CM from the measurement of the complex impedance.
- This process comprises:
- step 1 an application (step 1) of a voltage input signal Ue at the input of the measuring circuit.
- This application is performed by the network analyzer which can for example emit an input voltage Ue on the input terminal of the circuit CM;
- step 2 a measurement (step 2) of the output voltage Us at the terminals of the electric dipole comprising the capacitance CE of the measuring circuit CM and the insulation resistor Riso l.
- This measurement is performed by means of an analog digital converter which will digitize (step 2A) the voltage Us to transmit it in sampled form to the network analyzer;
- This determination further comprises a calculation of the value of the complex impedance of the dipole for each of the pulses ⁇ from the module and the angle of the impedance Z, according to the equation below:
- R represents the modulus of the complex impedance Z and ⁇ represents the angle (or phase) of the complex impedance Z.
- the determination step is performed by the network analyzer.
- the frequency analysis is performed over a frequency range (for example from 1 kHz to 5 kHz depending on the nominal value of the R, Risol and CE components) and comprises a fast FFT type Fourier transform. (according to an acronym well known to those skilled in the art meaning Fast Fourier Transform) digitized output voltage.
- the frequency analysis can be carried out by means of Goertzel filtering.
- Goertzel filtering is faster because, unlike the Fourier transform, it does not need to compute the entire spectrum but is limited to calculating a spectrum line of the sampled Fourier transform.
- the relative amplitude of the different frequency components is known. More precisely with a square signal taking the values +1 or -1, the amplitude of the component of the square signal is 4 / ⁇ at the fundamental frequency, the amplitude of the harmonic 3 is 4 / (3 ⁇ ⁇ ) and the amplitude of the harmonic 5 is 4 / (5 ⁇ ⁇ ).
- the frequency of the input signal corresponding to said fundamental frequency will be chosen so as to minimize the signal - to - noise ratio of the spectrum of the output voltage. This is possible for example by avoiding the frequencies linked to a power electronics such as an inverter for example in another part of the vehicle electronics or by avoiding the problems related to the aliasing of the signals of the power electronics. .
- the frequency of the input signal can also be chosen according to the nominal value of the components R, Risol and CE.
- the frequency of the input signal may be chosen such that the CE capacitance to be used is small. Indeed, the higher the capacity, the more expensive it usually is.
- the method further comprises:
- step 4 a determination (step 4) of the value of the insulation resistance Risol and of the capacitance CE of the measurement circuit CM from the impedance for at least one frequency considered. For this, we use the equation below:
- the calculation step 4 is for example implemented by a calculation block integrated in a digital processing unit of the network analyzer.
- the calculation block implementing step 4 can be implemented in the form of software modules or in the form of logic circuits.
- a value of the insulation resistance Riso l can be derived from each of the complex impedances. We can then compare the different isolation resistances to control the relevance of the measurement.
- the CE capacitance measurement enables the detection of the value of the EC capacitor deviating from its nominal value. the capacity. This makes it possible, for example, for abnormal aging to obtain an onboard diagnostic function of the vehicle electronics.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP13710469.1A EP2817644B1 (fr) | 2012-02-22 | 2013-02-15 | Procédé et système d'estimation de la résistance d'isolement entre une batterie et une masse électrique |
JP2014558179A JP2015508171A (ja) | 2012-02-22 | 2013-02-15 | バッテリと電気的接地との間の絶縁抵抗を推定するための方法及び装置 |
US14/380,494 US10302691B2 (en) | 2012-02-22 | 2013-02-15 | Method and system for estimating the insulation resistance between a battery and an electrical earth |
KR1020147026452A KR102021438B1 (ko) | 2012-02-22 | 2013-02-15 | 배터리와 전기 접지 사이의 절연 저항의 측정 방법 및 시스템 |
CN201380015598.5A CN104204823B (zh) | 2012-02-22 | 2013-02-15 | 用于估算电池与电接地极之间的绝缘电阻的方法和系统 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR1251591 | 2012-02-22 | ||
FR1251591A FR2987133B1 (fr) | 2012-02-22 | 2012-02-22 | Procede d'estimation de la resistance d'isolement entre une batterie et une masse electrique |
Publications (1)
Publication Number | Publication Date |
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WO2013124571A1 true WO2013124571A1 (fr) | 2013-08-29 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/FR2013/050320 WO2013124571A1 (fr) | 2012-02-22 | 2013-02-15 | Procede et systeme d'estimation de la resistance d'isolement entre une batterie et une masse electrique |
Country Status (7)
Country | Link |
---|---|
US (1) | US10302691B2 (fr) |
EP (1) | EP2817644B1 (fr) |
JP (1) | JP2015508171A (fr) |
KR (1) | KR102021438B1 (fr) |
CN (1) | CN104204823B (fr) |
FR (1) | FR2987133B1 (fr) |
WO (1) | WO2013124571A1 (fr) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2019179736A1 (fr) | 2018-03-23 | 2019-09-26 | IFP Energies Nouvelles | Procede de determination d'au moins deux resistances equivalentes d'isolement d'un systeme electrique |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR3014206B1 (fr) * | 2013-12-04 | 2015-12-11 | Renault Sas | Estimation de la resistance d'isolement entre une batterie de vehicule automobile et la masse |
CN107219404B (zh) * | 2016-03-21 | 2020-11-10 | 华为技术有限公司 | 一种频率调节的方法及装置 |
JP6725349B2 (ja) * | 2016-07-13 | 2020-07-15 | 株式会社ケーヒン | 地絡検知装置 |
JP6767801B2 (ja) * | 2016-07-13 | 2020-10-14 | 株式会社ケーヒン | 地絡検知装置 |
CN108333492B (zh) * | 2018-02-01 | 2021-01-01 | 宁德时代新能源科技股份有限公司 | 绝缘检测电路及方法、电池管理系统 |
CN113252980A (zh) * | 2021-03-31 | 2021-08-13 | 华为技术有限公司 | 一种光储系统及对地绝缘阻抗检测方法 |
KR20240011935A (ko) * | 2022-07-19 | 2024-01-29 | 현대자동차주식회사 | 이차전지의 절연 평가장치 |
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US5365179A (en) * | 1992-03-19 | 1994-11-15 | Electronic Development, Inc. | Apparatus and method for measuring ground impedance |
US5382946A (en) * | 1993-01-08 | 1995-01-17 | Ford Motor Company | Method and apparatus for detecting leakage resistance in an electric vehicle |
JP2003250201A (ja) | 2002-02-26 | 2003-09-05 | Nissan Motor Co Ltd | 車両用地絡検出装置 |
US20040130326A1 (en) * | 2002-10-16 | 2004-07-08 | Yazaki Corporation | Ground-fault detecting device and insulation resistance measuring device |
US20070008666A1 (en) * | 2005-07-11 | 2007-01-11 | Nissan Motor Co., Ltd. | Ground fault detector for vehicle |
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US5698964A (en) * | 1995-10-20 | 1997-12-16 | Dell Usa, L.P. | Adaptive power battery charging apparatus |
JP3678151B2 (ja) | 2001-01-11 | 2005-08-03 | 日産自動車株式会社 | 電気車両の地絡検出装置 |
JP2005114496A (ja) * | 2003-10-07 | 2005-04-28 | Yazaki Corp | 状態検出方法及び絶縁抵抗低下検出器 |
JP4280145B2 (ja) | 2003-10-23 | 2009-06-17 | 矢崎総業株式会社 | 絶縁抵抗低下検出器およびその自己診断方法 |
CN1873429B (zh) * | 2005-06-03 | 2010-12-08 | 华为技术有限公司 | 一种测量通讯线路电压、绝缘电阻及电容的方法和电路 |
US7863910B2 (en) * | 2005-08-29 | 2011-01-04 | Nec Corporation | Insulation resistance detecting apparatus |
JP4826264B2 (ja) * | 2006-01-19 | 2011-11-30 | 日産自動車株式会社 | 地絡検出装置 |
JP5052414B2 (ja) * | 2008-05-28 | 2012-10-17 | ダイハツ工業株式会社 | 車両用絶縁抵抗測定装置 |
JP2010256023A (ja) * | 2009-04-21 | 2010-11-11 | Pues Corp | 漏電検出装置 |
CN102341714B (zh) * | 2009-12-15 | 2016-01-20 | 株式会社Pues | 绝缘劣化检测装置 |
-
2012
- 2012-02-22 FR FR1251591A patent/FR2987133B1/fr not_active Expired - Fee Related
-
2013
- 2013-02-15 JP JP2014558179A patent/JP2015508171A/ja active Pending
- 2013-02-15 US US14/380,494 patent/US10302691B2/en active Active
- 2013-02-15 EP EP13710469.1A patent/EP2817644B1/fr active Active
- 2013-02-15 KR KR1020147026452A patent/KR102021438B1/ko active IP Right Grant
- 2013-02-15 CN CN201380015598.5A patent/CN104204823B/zh active Active
- 2013-02-15 WO PCT/FR2013/050320 patent/WO2013124571A1/fr active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5365179A (en) * | 1992-03-19 | 1994-11-15 | Electronic Development, Inc. | Apparatus and method for measuring ground impedance |
US5382946A (en) * | 1993-01-08 | 1995-01-17 | Ford Motor Company | Method and apparatus for detecting leakage resistance in an electric vehicle |
JP2003250201A (ja) | 2002-02-26 | 2003-09-05 | Nissan Motor Co Ltd | 車両用地絡検出装置 |
US20040130326A1 (en) * | 2002-10-16 | 2004-07-08 | Yazaki Corporation | Ground-fault detecting device and insulation resistance measuring device |
US20070008666A1 (en) * | 2005-07-11 | 2007-01-11 | Nissan Motor Co., Ltd. | Ground fault detector for vehicle |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2019179736A1 (fr) | 2018-03-23 | 2019-09-26 | IFP Energies Nouvelles | Procede de determination d'au moins deux resistances equivalentes d'isolement d'un systeme electrique |
Also Published As
Publication number | Publication date |
---|---|
US20150226782A1 (en) | 2015-08-13 |
FR2987133A1 (fr) | 2013-08-23 |
EP2817644A1 (fr) | 2014-12-31 |
CN104204823B (zh) | 2018-06-05 |
FR2987133B1 (fr) | 2014-02-07 |
JP2015508171A (ja) | 2015-03-16 |
CN104204823A (zh) | 2014-12-10 |
US10302691B2 (en) | 2019-05-28 |
EP2817644B1 (fr) | 2019-04-03 |
KR20140126398A (ko) | 2014-10-30 |
KR102021438B1 (ko) | 2019-09-16 |
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