WO2007080004A1 - Method and device for measuring current - Google Patents

Method and device for measuring current Download PDF

Info

Publication number
WO2007080004A1
WO2007080004A1 PCT/EP2006/068500 EP2006068500W WO2007080004A1 WO 2007080004 A1 WO2007080004 A1 WO 2007080004A1 EP 2006068500 W EP2006068500 W EP 2006068500W WO 2007080004 A1 WO2007080004 A1 WO 2007080004A1
Authority
WO
WIPO (PCT)
Prior art keywords
phase
measurement
current
measuring
controllable switching
Prior art date
Application number
PCT/EP2006/068500
Other languages
German (de)
French (fr)
Inventor
Tero Jaervelaeinen
Gilles Schmitt
Original Assignee
Robert Bosch Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Publication of WO2007080004A1 publication Critical patent/WO2007080004A1/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
    • G01R19/2506—Arrangements for conditioning or analysing measured signals, e.g. for indicating peak values ; Details concerning sampling, digitizing or waveform capturing
    • G01R19/2509—Details concerning sampling, digitizing or waveform capturing
    • 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
    • G01R31/40—Testing power supplies
    • G01R31/42—AC power supplies
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/0003—Details of control, feedback or regulation circuits
    • H02M1/0009—Devices or circuits for detecting current in a converter
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/539—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency
    • H02M7/5395—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency by pulse-width modulation

Definitions

  • the invention relates to a method for current measurement with the features mentioned in claim 1.
  • the invention relates to a device for measuring current with the features mentioned in claim 6.
  • Methods for current measurement are required, in particular, in the case of clocked applications in the motor vehicle sector, in which, in particular by means of an inverter, a sinusoidal current supply of a consumer, such as an electrical machine, e.g. an Asynchronous rotary machine is generated.
  • a sinusoidal current supply of a consumer such as an electrical machine, e.g. an Asynchronous rotary machine is generated.
  • the measured values obtained serve to monitor, control or protect by switching off when a predetermined limit value is exceeded.
  • the transistors of an inverter are driven by predetermined switching times. This allows a timely, consecutive measurement of all three streams.
  • the inventive method with the features mentioned in claim 1 offers the advantage that the fact that the clock patterns are shifted or changed in time when a measurement window falls below a predetermined size, such that a measurement window of sufficient size is formed, essentially no human can be generated perceptible noises and at the same time using a current measuring resistor all phase currents can be measured.
  • controllable switching elements by means of controllable switching elements, a 3-phase AC current is generated.
  • a total of six controllable switching elements are provided, which form an inverter and generate 3-phase three-phase current from a direct current, wherein the control unit is designed accordingly.
  • a three-phase asynchronous motor is energized as a consumer.
  • the control unit and the inverter for generating three-phase variable frequency is formed to e.g. to allow starting of the three-phase asynchronous motor without further aids.
  • each measuring window the measurement of a phase current is possible.
  • the current measurement of all phase currents takes place on a current measuring resistor, through which a sum current, formed from the sum of all phase currents, flows.
  • the measuring windows allow the measurement of each - A -
  • two measurement windows are formed at each start of the period in order to determine two phase currents and to calculate the third phase current from the already determined phase currents.
  • the invention further includes a device for measuring current, in particular designed for current measurement in a multiphase
  • Switching element acting control signals is formed to a substantially sinusoidal current flow of the
  • Measuring window for measuring electrical currents in particular of phase currents form.
  • the device according to the invention can be embodied as an inverter, with which three-phase three-phase current can be generated.
  • the device may have a capacitance, formed by an electrolytic capacitor, which serves as a smoothing capacitor, wherein an electrolytic capacitor current increase can be minimized by the device or the method.
  • the controllable switching elements may be formed by semiconductor devices such as transistors.
  • a current measuring resistor can be provided, through which a sum current, formed from all phase currents of the three-phase current, is conducted. It is preferably provided that the consumer is a three-phase asynchronous motor.
  • phase current is possible in each measurement window, so that the measurement of all phase currents is possible.
  • control unit is designed to generate control signals which control the controllable switching elements in such a way that two measurement windows are generated at each start of the period. This allows, as the sum of the phase currents of 3-phase three-phase current is equal to zero, the determination of all three phase currents, wherein the current measurement takes place on a current measuring resistor through which the Summen ström formed from the three phase currents, is passed.
  • Figure 1 is a schematic representation of a circuit according to the invention.
  • Figure 2 is a schematic representation of inventive
  • Fig. 1 there is shown a circuit having an inverter function for driving a load such as e.g. a star-connected 3-phase asynchronous motor (PSM or ASM) shown.
  • a load such as e.g. a star-connected 3-phase asynchronous motor (PSM or ASM) shown.
  • PSM 3-phase asynchronous motor
  • the circuit has two input terminals 1, 2, with which the circuit to a DC voltage source (not shown) can be connected.
  • the circuit has a parallel to the input terminals 1, 2 connected to the electrolytic capacitor 3.
  • the circuit has six transistors 4 - 9, which are arranged in pairs and form an inverter for generating a 3-phase three-phase current.
  • Lines 10 - 12 form connections of connection points 13 - 15 of each pair of transistors 4 - 9 with windings 16 - 18 of a three-phase asynchronous motor (not shown).
  • a current measuring resistor 20 is arranged in a line section 19, which establishes a connection from the input terminal 2 to the transistors 5, 7, 9, a current measuring resistor 20 is arranged.
  • a measuring amplifier which has an operational amplifier 21.
  • an A / D converter 22 is connected to the operational amplifier 21, an A / D converter 22 is connected.
  • a current measuring device 23 is connected to the A / D converter 22.
  • a control unit 24 which is connected to the transistors 4 - 9 by control lines (not shown).
  • control unit 24 In operation, the control unit 24 generates, for example, pulse-width-modulated drive signals (see FIG. 2) which cause, by driving the transistors 4-9, three mutually phase-shifted electrical currents with a substantially sinusoidal profile, which are known in the windings 16-18 generate magnetic rotating field.
  • pulse-width-modulated drive signals see FIG. 2 which cause, by driving the transistors 4-9, three mutually phase-shifted electrical currents with a substantially sinusoidal profile, which are known in the windings 16-18 generate magnetic rotating field.
  • the transistors 4 - 9 are driven by the drive signals such that at the beginning of each period two measurement windows 25, 26 are available for measuring two phase currents.
  • a first phase current can then be detected in the first measuring window 25, for example a phase current flowing through the transistor 4 and the line 10.
  • a second measurement is carried out in which both the phase current flowing through the transistor 4 and the line 10 as well as the second phase current flowing through the transistor 6 and the line 11 are detected as a summation current.
  • the measured values After the measured values have been amplified by the operational amplifier 21, they are converted into digital values by the A / D converter 22 and supplied to the current measuring device 23. After two measurements have been taken, the difference between the two measured values obtained during the measurements in the two measuring windows 25, 26 can be determined by forming the difference between the phase current flowing through the transistor 6 and the line 11. Furthermore, since the sum current of all three phase currents must be equal to zero, the third phase current is calculated from the two already determined phase currents.
  • the drive may also be such that e.g. in the second measuring window, only the phase current flowing through the transistor 6 and the line 11 is determined. The difference between the two measured values is then eliminated.
  • the clock patterns are shifted or changed in time.
  • the displacement takes place in such a way that again measurement windows are available for measuring the phase currents.
  • the measurement windows are shifted or changed in such a way that two measurement windows for measuring two phase currents are available again at the beginning of a period. If the pulse width modulated drive signal has a large amplitude, in this case, the measurement window can be increased.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Control Of Ac Motors In General (AREA)

Abstract

The invention relates to a method for measuring current, in particular in a multi-phase power supply system, in which a desired current flow in a load is effected by at least one controllable switching element, wherein a control unit produces driving signals acting on the at least one controllable switching element in order to achieve a desired current flow in the load, wherein clock patterns of the driving signals form measurement windows for measuring electric currents, in particular phase currents. Provision is made for the clock patterns to be offset in terms of time if a measurement window falls below a predetermined size such that a measurement window of a sufficient size is formed. The invention furthermore relates to a device for current measurement, in particular for carrying out the method according to the invention.

Description

ROBERT BOSCH GMBH, 70442 STUTTGARTROBERT BOSCH GMBH, 70442 STUTTGART
R. 313198R. 313198
Titeltitle
Verfahren und Vorrichtung zur StrommessungMethod and device for current measurement
Die Erfindung betrifft ein Verfahren zur Strommessung mit den im Anspruch 1 genannten Merkmalen.The invention relates to a method for current measurement with the features mentioned in claim 1.
Ferner betrifft die Erfindung eine Vorrichtung zur Strommessung mit den im Anspruch 6 genannten Merkmalen.Furthermore, the invention relates to a device for measuring current with the features mentioned in claim 6.
Stand der TechnikState of the art
Verfahren zur Strommessung sind insbesondere bei getakteten Anwendungen im Kfz-Bereich erforderlich, bei denen insbesondere mit- tels eines Wechselrichters eine Sinusbestromung eines Verbrauchers wie einer elektrische Maschine, z.B. einer Asynchrondrehstrommaschine erzeugt wird. Die ermittelten Messwerte dienen dabei zur Überwachung, zur Regelung oder zum Schutz durch Abschaltung bei Überschreiten eines vorgegebenen Grenzwerts.Methods for current measurement are required, in particular, in the case of clocked applications in the motor vehicle sector, in which, in particular by means of an inverter, a sinusoidal current supply of a consumer, such as an electrical machine, e.g. an Asynchronous rotary machine is generated. The measured values obtained serve to monitor, control or protect by switching off when a predetermined limit value is exceeded.
Üblicherweise werden zur Strommessung niederohmige Strommesswiderstände, sogenannte Strommessshunts bzw. Shuntwi- derstände mit einem nachgeschalteten Differenzverstärker zur Signalaufbereitung verwendet.Usually low-current current measuring resistors, so-called current measuring shunts or shunt resistors with a downstream differential amplifier are used for current measurement for signal conditioning.
Bei einer konventionellen Stromregelung in einem Drehstromnetz mit drei Phasen ist es erforderlich, mindestens zwei Phasenströme der drei Phasenströme zu messen. Um die benötigen Messungen und einen Überstromschutz zu realisieren werden drei Shuntwiderstände benötigt. Es ist dabei eine zeitgleiche Messung des Wechselrichters möglich. Dabei erzeugt die Taktung der Schaltzustände kein hörbares Geräusch, wenn keine periodischen Änderungen im Taktmuster vorgenommen werden um den Strom zu messen.In a conventional current control in a three-phase network with three phases, it is necessary to measure at least two phase currents of the three phase currents. To need the measurements and To realize overcurrent protection, three shunt resistors are required. It is a simultaneous measurement of the inverter possible. In this case, the timing of the switching states produces no audible noise when no periodic changes in the clock pattern are made to measure the current.
Bei einer Messung mit nur einem Shuntwiderstand werden die Transistoren eines Wechselrichters durch vorgegebene Schaltzeiten angesteuert. Dies erlaubt eine zeitnahe, aufeinanderfolgende Messung aller drei Ströme.In a measurement with only one shunt resistor, the transistors of an inverter are driven by predetermined switching times. This allows a timely, consecutive measurement of all three streams.
Jedoch ist hierbei eine minimale Messfenstergröße erforderlich. So werden periodisch, z.B. im ms-Bereich, alle zur Strommessung der drei Phasenströme benötigten Schaltzustände der Transistoren durchlaufen, um so eine zeitnahe Messung der drei Phasenströme zu ermöglichen. Diese periodische Abweichung vom Bestromungs- Taktmuster, das zur Erzeugung einer sinusförmigen Bestromung verwendet wird, erzeugt aber ein hörbares Geräusch, wenn normalerweise mit 20 kHz getaktet wird, da die Änderungen dann Frequen- zen im hörbaren Bereich erzeugen. Die Taktfrequenz kann nicht mehr erhöht werden, weil noch mehr Taktverluste entstehen und Totzeiteffekte nicht vernachlässigbar sind.However, this requires a minimum measurement window size. Thus, periodically, e.g. in the ms-range, all required to measure the current of the three phase currents switching states of the transistors, so as to enable a timely measurement of the three phase currents. However, this periodic deviation from the current clock pattern used to generate sinusoidal current will produce audible noise when normally clocked at 20kHz, since the changes will then produce frequencies in the audible range. The clock frequency can not be increased, because even more clock losses occur and dead time effects are not negligible.
Es sind weitere Verfahren bekannt, die unter Verwendung eines Shuntwiderstandes die Messung der drei Phasenströme erlauben, siehe z.B. Application note von Texas Instruments, Three Phase Cur- rent Measurement Using a Single Line Resitor on the TMS320F240, Literature number: BPRA077, May 1998). Dies Verfahren hat jedoch den Nachteil, dass die Messung asynchron zu der Taktperiode er- folgt. Daher muss der Messzeitpunkt bei diesem Verfahren für jede Taktperiode neu berechnet werden und die Tastverhältnisse müssen entsprechend angepasst werden. Dies bedeutet für einen μ- Controller einer Steuereinheit einen hohen Rechenaufwand allein aufgrund der Strommessung. Dieses Verfahren und andere, ver- gleichbare Verfahren, bei denen das Taktmuster zyklisch geändert wird, verursachen auch ein erhebliches akustisches Geräusch bei Taktfrequenzen von 20 kHz.Other methods are known that allow the measurement of the three phase currents using a shunt resistor, see eg Application note of Texas Instruments, Three Phase Current Measurement Using a Single Line Resistor on the TMS320F240, Literature Number: BPRA077, May 1998). However, this method has the disadvantage that the measurement is performed asynchronously with the clock period. Therefore, the measurement time must be recalculated for each clock period in this process and the duty cycles must be adjusted accordingly. This means for a μ controller of a control unit, a high computational effort due to the current measurement. This method and others, Similar methods, in which the clock pattern is cyclically changed, also cause significant acoustic noise at clock frequencies of 20 kHz.
Offenbarung der ErfindungDisclosure of the invention
Das erfindungsgemäße Verfahren mit den im Anspruch 1 genannten Merkmalen bietet demgegenüber den Vorteil, dass dadurch, dass die Taktmuster zeitlich verschoben oder geändert werden, wenn ein Messfenster eine vorgegebene Größe unterschreitet, derart, das ein Messfenster ausreichender Größe gebildet wird, im Wesentlichen keine vom Menschen wahrnehmbaren Geräusche erzeugt werden und zugleich unter Verwendung eines Strommesswiderstands alle Phasenströme gemessen werden können.The inventive method with the features mentioned in claim 1 offers the advantage that the fact that the clock patterns are shifted or changed in time when a measurement window falls below a predetermined size, such that a measurement window of sufficient size is formed, essentially no human can be generated perceptible noises and at the same time using a current measuring resistor all phase currents can be measured.
In bevorzugter Ausführungsform ist vorgesehen, dass mittels steuerbarer Schaltelemente ein 3-phasiger Drehstrom, erzeugt wird. Hierzu sind insgesamt sechs steuerbare Schaltelemente vorgesehen, die einen Wechselrichter bilden und aus einem Gleichstrom 3-phasigen Drehstrom erzeugen, wobei die Steuereinheit entsprechend ausgebildet ist.In a preferred embodiment, it is provided that by means of controllable switching elements, a 3-phase AC current is generated. For this purpose, a total of six controllable switching elements are provided, which form an inverter and generate 3-phase three-phase current from a direct current, wherein the control unit is designed accordingly.
Es ist bevorzugt vorgesehen, dass als Verbraucher ein Drehstrom- Asynchronmotor bestromt wird. Dabei ist die Steuereinheit und der Wechselrichter zur Erzeugung von Drehstrom variabler Frequenz ausgebildet, um z.B. ein Anlaufen des Drehstrom-Asynchronmotors ohne weitere Hilfsmittel zu ermöglichen.It is preferably provided that a three-phase asynchronous motor is energized as a consumer. In this case, the control unit and the inverter for generating three-phase variable frequency is formed to e.g. to allow starting of the three-phase asynchronous motor without further aids.
Ferner ist bevorzugt vorgesehen, dass in je einem Messfenster die Messung eines Phasenstromes möglich ist. Hierzu erfolgt die Strommessung aller Phasenströme an einem Strommesswiderstand, durch den ein Summenstrom, gebildet aus der Summe aller Phasenströme, fließt. Dabei erlauben die Messfenster die Messung jedes - A -Furthermore, it is preferably provided that in each case a measuring window, the measurement of a phase current is possible. For this purpose, the current measurement of all phase currents takes place on a current measuring resistor, through which a sum current, formed from the sum of all phase currents, flows. The measuring windows allow the measurement of each - A -
einzelnen Phasenstromes oder alternativ die Messung einer ausgewählten Anzahl der Phasenströme.single phase current or alternatively the measurement of a selected number of phase currents.
Bevorzugt ist vorgesehen, dass bei jedem Periodenbeginn 2 Mess- fenster gebildet werden, um so zwei Phasenströme zu bestimmen und den dritten Phasenstrom aus den bereits bestimmten Phasenströmen zu berechnen.It is preferably provided that two measurement windows are formed at each start of the period in order to determine two phase currents and to calculate the third phase current from the already determined phase currents.
Zur Erfindung gehört ferner eine Vorrichtung zur Strommessung, ins- besondere ausgebildet zur Strommessung in einem mehrphasigenThe invention further includes a device for measuring current, in particular designed for current measurement in a multiphase
Stromnetz, mit wenigstens einem steuerbaren Schaltelement zur imPower grid, with at least one controllable switching element for im
Wesentlichen sinusförmigen Bestromung eines Verbrauchers, wobei eine Steuereinheit zur Erzeugung von auf das wenigstens eineSubstantially sinusoidal energization of a consumer, wherein a control unit for generating on the at least one
Schaltelement wirkenden Ansteuersignalen ausgebildet ist, um eine im Wesentlichen sinusförmige Bestromung Bestromung desSwitching element acting control signals is formed to a substantially sinusoidal current flow of the
Verbrauchers zu erreichen, wobei Taktmuster der AnsteuersignaleTo achieve consumer, with clock pattern of the drive signals
Messfenster zur Messung von elektrischen Strömen, insbesondere von Phasenströmen, bilden. Dadurch, dass die Steuereinheit ferner derart ausgebildet ist, dass die Taktmuster zeitlich verschoben wer- den, wenn ein Messfenster eine vorgegebene Größe unterschreitet, derart, das ein Messfenster ausreichender Größe zur Verfügung steht, wird eine erhebliche Geräuschreduzierung erreicht.Measuring window for measuring electrical currents, in particular of phase currents form. The fact that the control unit is also designed such that the clock patterns are shifted in time when a measurement window falls below a predetermined size, such that a measurement window of sufficient size is available, results in a considerable reduction in noise.
Die erfindungsgemäße Vorrichtung kann dabei als Wechselrichter ausgebildet sein, mit der 3-phasiger Drehstrom erzeugt werden kann. Hierzu kann die Vorrichtung eine Kapazität, gebildet durch einen E- lektrolytkondensator, aufweisen, der als Glättungskondensator dient, wobei durch die Vorrichtung bzw. das Verfahren eine Elektrolytkondensatorstromerhöhung minimiert werden kann. Die steuerbaren Schaltelemente können durch Halbleiterbauelement wie Transistoren gebildet sein. Ferner kann ein Strommesswiderstand vorgesehen sein, durch den im ein Summenstrom, gebildet aus allen Phasenströmen des 3-phasigen Drehstromes geleitet wird. Bevorzugt ist dabei vorgesehen, dass der Verbraucher ein Drehstrom-Asynchronmotor ist.The device according to the invention can be embodied as an inverter, with which three-phase three-phase current can be generated. For this purpose, the device may have a capacitance, formed by an electrolytic capacitor, which serves as a smoothing capacitor, wherein an electrolytic capacitor current increase can be minimized by the device or the method. The controllable switching elements may be formed by semiconductor devices such as transistors. Furthermore, a current measuring resistor can be provided, through which a sum current, formed from all phase currents of the three-phase current, is conducted. It is preferably provided that the consumer is a three-phase asynchronous motor.
In einer bevorzugten Ausführungsform ist vorgesehen, dass in je ei- nem Messfenster die Messung eines Phasenstromes möglich ist, sodass die Messung aller Phasenströme möglich ist.In a preferred embodiment, it is provided that the measurement of a phase current is possible in each measurement window, so that the measurement of all phase currents is possible.
In einer bevorzugten Ausführungsform ist vorgesehen, dass die Steuereinheit zur Erzeugung von Steuersignalen ausgebildet ist, die die steuerbaren Schaltelemente derart ansteuern, dass beijedem Periodenbeginn zwei Messfenster, erzeugt sind. Dies erlaubt, da die Summe der Phasenströme von 3-phasigen Drehstrom gleich Null ist, die Bestimmung aller drei Phasenströme, wobei die Strommessung an einem Strommesswiderstand erfolgt, durch den der Summen- ström, gebildet aus den drei Phasenströmen, geleitet wird.In a preferred embodiment, it is provided that the control unit is designed to generate control signals which control the controllable switching elements in such a way that two measurement windows are generated at each start of the period. This allows, as the sum of the phase currents of 3-phase three-phase current is equal to zero, the determination of all three phase currents, wherein the current measurement takes place on a current measuring resistor through which the Summen ström formed from the three phase currents, is passed.
Die Erfindung wird nachfolgend in einem Ausführungsbeispiel anhand der zugehörigen Zeichnungen näher erläutert. Es zeigen:The invention will be explained in more detail in an embodiment with reference to the accompanying drawings. Show it:
Figur 1 eine schematische Darstellung einer erfindungsgemäßen Schaltung, undFigure 1 is a schematic representation of a circuit according to the invention, and
Figur 2 eine schematische Darstellung von erfindungsgemäßenFigure 2 is a schematic representation of inventive
Ansteuersignalen.Drive signals.
In Figur 1 ist eine Schaltung mit Wechselrichterfunktion zur Ansteuerung eines Verbrauchers, wie z.B. eines sterngeschalteten 3-Phasen Asynchronmotors (PSM oder ASM) dargestellt.In Fig. 1 there is shown a circuit having an inverter function for driving a load such as e.g. a star-connected 3-phase asynchronous motor (PSM or ASM) shown.
Die Schaltung weist zwei Eingangsanschlüsse 1 , 2 auf, mit denen die Schaltung an eine Gleichspannungsquelle (nicht dargestellt) angeschlossen werden kann. Die Schaltung weist einen parallel zu den Eingangsanschlüssen 1 , 2 angeschlossenen Elektrolytkondensator 3 auf. Ferner weist die Schaltung sechs Transistoren 4 - 9 auf, die paarweise angeordnet sind und einen Wechselrichter zur Erzeugung eines 3-phasigen Drehstromes bilden. Leitungen 10 - 12 bilden Verbindungen von Anschlusspunkten 13 - 15 von jedem Transistorpaar 4 - 9 mit Wicklungen 16 - 18 eines 3-Phasen Drehstromasynchronmotors (nicht dargestellt).The circuit has two input terminals 1, 2, with which the circuit to a DC voltage source (not shown) can be connected. The circuit has a parallel to the input terminals 1, 2 connected to the electrolytic capacitor 3. Furthermore, the circuit has six transistors 4 - 9, which are arranged in pairs and form an inverter for generating a 3-phase three-phase current. Lines 10 - 12 form connections of connection points 13 - 15 of each pair of transistors 4 - 9 with windings 16 - 18 of a three-phase asynchronous motor (not shown).
In einem Leitungsabschnitt 19, der eine Verbindung von dem Ein- gangsanschluss 2 mit den Transistoren 5, 7, 9 herstellt, ist ein Strommesswiderstand 20 angeordnet. Mit dem Strommesswiderstand 20 ist ein Messverstärker verbunden, der einen Operationsverstärker 21 aufweist. Mit dem Operationsverstärker 21 ist ein A/D- Wandler 22 verbunden. Mit dem A/D-Wandler 22 ist eine Strommesseinrichtung 23 verbunden. Mit der Strommesseinrichtung 23 ist eine Steuereinheit 24 verbunden, die durch nicht dargestellte Steuerleitungen mit den Transistoren 4 - 9 verbunden ist.In a line section 19, which establishes a connection from the input terminal 2 to the transistors 5, 7, 9, a current measuring resistor 20 is arranged. Connected to the current measuring resistor 20 is a measuring amplifier which has an operational amplifier 21. To the operational amplifier 21, an A / D converter 22 is connected. A current measuring device 23 is connected to the A / D converter 22. Connected to the current measuring device 23 is a control unit 24 which is connected to the transistors 4 - 9 by control lines (not shown).
Im Betrieb erzeugt die Steuereinheit 24 bspw. pulsweitenmodulierte Ansteuersignale (siehe Fig. 2), die bewirken, das durch Ansteuerung der Transistoren 4 - 9 drei zueinander phasenverschobene elektrische Ströme mit im wesentlichen sinusförmigen Verlauf erzeugt werden, die in den Wicklungen 16 - 18 ein bekanntes magnetisches Drehfeld erzeugen.In operation, the control unit 24 generates, for example, pulse-width-modulated drive signals (see FIG. 2) which cause, by driving the transistors 4-9, three mutually phase-shifted electrical currents with a substantially sinusoidal profile, which are known in the windings 16-18 generate magnetic rotating field.
Ferner werden durch die Ansteuersignale die Transistoren 4 - 9 derart angesteuert, dass zu Beginn jeder Periode zwei Messfenster 25, 26 zur Messung von zwei Phasenströmen zur Verfügung stehen. Mit Hilfe des Strommesswiderstands 20 kann dann im ersten Messfenster 25 ein erster Phasenstrom erfasst werden, bspw. ein durch den Transistor 4 und die Leitung 10 fließende Phasenstrom. Anschließend wird im zweiten Messfenster 26 eine zweite Messung durchgeführt, bei der sowohl der durch den Transistor 4 und die Leitung 10 fließende Phasenstrom als auch der durch den Transistor 6 und die Leitung 11 fließende zweite Phasenstrom als Summenstrom erfasst wird.Further, the transistors 4 - 9 are driven by the drive signals such that at the beginning of each period two measurement windows 25, 26 are available for measuring two phase currents. With the aid of the current measuring resistor 20, a first phase current can then be detected in the first measuring window 25, for example a phase current flowing through the transistor 4 and the line 10. Subsequently, in the second measuring window 26, a second measurement is carried out in which both the phase current flowing through the transistor 4 and the line 10 as well as the second phase current flowing through the transistor 6 and the line 11 are detected as a summation current.
Nachdem die Messwerte von dem Operationsverstärker 21 verstärkt wurden, werden sie vom A/D-Wandler 22 in Digitalwerte gewandelt und der Strommesseinrichtung 23 zugeführt. Nach Durchführung zweier Messungen kann aus der Differenz der beiden Messwerte, die während der Messungen in den beiden Messfenstern 25, 26 gewonnen wurden, durch Differenzbildung der durch den Transistor 6 und die Leitung 11 fließende Phasenstrom bestimmt werden. Ferner wird, da der Summenstrom aller drei Phasenströme gleich Null sein muss, aus den beiden bereits ermittelten Phasenströmen der dritte Phasenstrom berechnet.After the measured values have been amplified by the operational amplifier 21, they are converted into digital values by the A / D converter 22 and supplied to the current measuring device 23. After two measurements have been taken, the difference between the two measured values obtained during the measurements in the two measuring windows 25, 26 can be determined by forming the difference between the phase current flowing through the transistor 6 and the line 11. Furthermore, since the sum current of all three phase currents must be equal to zero, the third phase current is calculated from the two already determined phase currents.
Alternativ hierzu kann die Ansteuerung auch derart erfolgen, dass z.B. im zweiten Messfenster lediglich der durch den Transistor 6 und die Leitung 11 fließende Phasenstrom bestimmt wird. Die Differenzbildung der beiden Messwerte entfällt dann.Alternatively, the drive may also be such that e.g. in the second measuring window, only the phase current flowing through the transistor 6 and the line 11 is determined. The difference between the two measured values is then eliminated.
Wenn ein Zeitfenster zur Strommessung zu klein ist, werden die Taktmuster zeitlich verschoben oder geändert. Dabei erfolgt die Ver- Schiebung derart, das wieder Messfenster zur Messung der Phasenströme zu Verfügung stehen. Insbesondere werden die Messfenster derart verschoben oder geändert, dass wieder am Anfang einer Periode zwei Messfenster zur Messung zweier Phasenströme zur Verfügung stehen. Wenn das pulsweitenmodulierte Ansteuersignal eine große Amplitude aufweist, kann in diesem Fall das Messfenster vergrößert werden. If a time window for current measurement is too small, the clock patterns are shifted or changed in time. In this case, the displacement takes place in such a way that again measurement windows are available for measuring the phase currents. In particular, the measurement windows are shifted or changed in such a way that two measurement windows for measuring two phase currents are available again at the beginning of a period. If the pulse width modulated drive signal has a large amplitude, in this case, the measurement window can be increased.

Claims

R. 313198Patentansprüche R. 313198Patent claims
1. Verfahren zur Strommessung, insbesondere in einem mehrphasigen Stromnetz, bei dem durch wenigstens ein steuerbares Schaltelement eine gewünschte Bestromung eines Verbrauchers erfolgt, wobei eine Steuereinheit auf das wenigstens eine steuerbare Schaltelement wirkende Ansteuersignale erzeugt, um die gewünschte Bestromung des Verbrauchers erreichen, wobei Taktmuster der Ansteuersignale Messfenster zur Messung von elektrischen Strömen, insbesondere von Phasenströmen, bilden, dadurch gekennzeichnet, dass die Taktmuster zeitlich verschoben werden, wenn ein Messfenster eine vorgegebene Größe unterschreitet, derart, das ein Messfenster ausreichender Größe zur Verfügung gebildet wird.1. A method for current measurement, in particular in a multi-phase power grid, in which by at least one controllable switching element, a desired energization of a consumer takes place, wherein a control unit on the at least one controllable switching element acting drive signals generated to achieve the desired energization of the consumer, wherein clock pattern of Control signals measuring windows for measuring electrical currents, in particular of phase currents, form, characterized in that the clock patterns are shifted in time when a measurement window falls below a predetermined size, such that a measurement window of sufficient size is available.
2. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass mittels steuerbarer Schaltelemente (4 - 9) ein mehrphasiger Dreh- ström erzeugt wird.2. The method according to claim 1, characterized in that by means of controllable switching elements (4-9) a multi-phase rotary Ström is generated.
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass als Verbraucher ein Drehstrom-Asynchronmotor oder ein Permanentmagnet-Synchronmotor bestromt wird.3. The method according to claim 1 or 2, characterized in that a three-phase asynchronous motor or a permanent magnet synchronous motor is energized as a consumer.
4. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass in je einem Messfenster die Messung eines Phasenstromes möglich ist.4. The method according to any one of the preceding claims, characterized in that in each case a measuring window, the measurement of a phase current is possible.
5. Verfahren nach Anspruch 4, dadurch gekennzeichnet, dass die steuerbaren Schaltelemente (4 - 9) derart angesteuert werden, dass (m-1 ) Messfenster gebildet werden. 5. The method according to claim 4, characterized in that the controllable switching elements (4-9) are controlled such that (m-1) measuring windows are formed.
6. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass, dass bei jedem Periodenbeginn oder Periodenende (m-1 ) Messfenster gebildet werden.6. The method according to claim 5, characterized in that at each period start or period end (m-1) measuring windows are formed.
7. Vorrichtung zur Strommessung, insbesondere zur Durchführung des Verfahrens nach einem der vorhergehenden Ansprüche, insbesondere ausgebildet zur Strommessung in einem mehrphasigen Stromnetz, mit wenigstens einem steuerbaren Schaltelement zur gewünschten Bestromung eines Verbrauchers, wobei eine Steuer- einheit zur Erzeugung von auf das wenigstens eine Schaltelement wirkenden Ansteuersignalen ausgebildet ist, um die gewünschte Bestromung des Verbrauchers erreichen, wobei Taktmuster der Ansteuersignale Messfenster zur Messung von elektrischen Strömen, insbesondere von Phasenströmen, bilden, dadurch gekennzeich- net, dass die Steuereinheit (24) ferner derart ausgebildet ist, dass die Taktmuster zeitlich verschoben oder geändert werden, wenn ein Messfenster eine vorgegebene Größe unterschreitet, derart, das ein Messfenster ausreichender Größe zur Verfügung steht, in dem das Taktmuster so wenig wie möglich geändert wird.7. A device for current measurement, in particular for carrying out the method according to any one of the preceding claims, in particular designed for current measurement in a multi-phase power grid, with at least one controllable switching element for the desired energization of a consumer, wherein a control unit for generating on the at least one switching element Actuating control signals is formed to achieve the desired energization of the consumer, wherein clock patterns of the control signals measuring windows for measuring electrical currents, in particular of phase currents form, thereby gekennzeich- net that the control unit (24) is further designed such that the clock pattern in time be shifted or changed when a measurement window falls below a predetermined size, such that a measurement window of sufficient size is available in which the clock pattern is changed as little as possible.
8. Vorrichtung nach Anspruch 7, dadurch gekennzeichnet, dass die Vorrichtung zur Erzeugung von mehrphasigen Drehstrom ausgebildet ist.8. Apparatus according to claim 7, characterized in that the device is designed for generating multi-phase AC current.
9. Vorrichtung nach Anspruch 7 oder 8, dadurch gekennzeichnet, dass der Verbraucher oder ein Permanentmagnet- Synchronmotor ein Drehstrom-Asynchronmotor ist.9. Apparatus according to claim 7 or 8, characterized in that the consumer or a permanent magnet synchronous motor is a three-phase asynchronous motor.
10. Vorrichtung nach einem der Ansprüche 7 bis 9, dadurch ge- kennzeichnet, dass in je einem Messfenster die Messung eines10. Device according to one of claims 7 to 9, character- ized in that in each case a measurement window, the measurement of a
Phasenstromes möglich ist.Phase current is possible.
11. Vorrichtung nach Anspruch 9, dadurch gekennzeichnet, dass die Steuereinheit (24) zur Erzeugung von Steuersignalen aus- gebildet ist, die die steuerbaren Schaltelemente (4 - 9) derart ansteuern, dass (m-1 ) Messfenster erzeugt sind.11. The device according to claim 9, characterized in that the control unit (24) for generating control signals from is formed, which drive the controllable switching elements (4-9) such that (m-1) measurement window are generated.
12. Vorrichtung nach Anspruch 11 , dadurch gekennzeichnet, dass, dass bei jedem Periodenbeginn oder Periodenende (m-1 ) Messfenster erzeugt sind. 12. The device according to claim 11, characterized in that at each period start or period end (m-1) measuring windows are generated.
PCT/EP2006/068500 2005-12-28 2006-11-15 Method and device for measuring current WO2007080004A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102005062759A DE102005062759A1 (en) 2005-12-28 2005-12-28 Current measuring method for multi-phase power supply system in motor vehicle, involves shifting clock sample, when measuring window falls below preset parameter, in such a way that another window of sufficient parameter is formed
DE102005062759.5 2005-12-28

Publications (1)

Publication Number Publication Date
WO2007080004A1 true WO2007080004A1 (en) 2007-07-19

Family

ID=37781984

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2006/068500 WO2007080004A1 (en) 2005-12-28 2006-11-15 Method and device for measuring current

Country Status (2)

Country Link
DE (1) DE102005062759A1 (en)
WO (1) WO2007080004A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111527691A (en) * 2018-01-04 2020-08-11 罗伯特·博世有限公司 Method for operating a synchronous machine

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008001025A1 (en) * 2008-04-07 2009-10-08 Robert Bosch Gmbh Method and device for current measurement in phase lines
DE102010001181A1 (en) * 2010-01-25 2011-07-28 Robert Bosch GmbH, 70469 Method and device for current measurement in a multiphase power network
DE102011003897A1 (en) * 2011-02-10 2012-08-16 Robert Bosch Gmbh Method and device for current measurement
CN102175907A (en) * 2011-03-10 2011-09-07 华北电力大学（保定） Flexible wide area power grid phase measurement system
DE102013216224A1 (en) * 2013-08-15 2015-02-19 Robert Bosch Gmbh Method and device for determining phase currents and an exciter current of an electrical machine and motor system
DE102018115821A1 (en) * 2018-06-29 2020-01-02 Elmos Semiconductor Aktiengesellschaft Method for determining the phase currents in a multi-phase H-bridge to control a PMSM
DE102018115844A1 (en) * 2018-06-29 2020-01-02 Elmos Semiconductor Aktiengesellschaft Method for determining the phase currents in a multi-phase H-bridge for controlling a PMSM using a single shunt resistor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3529591A1 (en) * 1985-08-19 1987-02-26 Siemens Ag Method and device for operating an invertor
US5146148A (en) * 1988-11-04 1992-09-08 Europe Patent Ltd. Process and a device for changing the effective speed of a polyphase asynchronous motor and a suitable motor system for the application of the process
EP0502226A1 (en) * 1991-03-06 1992-09-09 Siemens Aktiengesellschaft Method and apparatus for simulating the currents in an inverter fed rotating field machine
US5969958A (en) * 1995-01-23 1999-10-19 Danfoss Method for measuring phase currents in an inverter
US20060006899A1 (en) * 2004-07-12 2006-01-12 Ronan De Larminat Current sensing in a two-phase motor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3529591A1 (en) * 1985-08-19 1987-02-26 Siemens Ag Method and device for operating an invertor
US5146148A (en) * 1988-11-04 1992-09-08 Europe Patent Ltd. Process and a device for changing the effective speed of a polyphase asynchronous motor and a suitable motor system for the application of the process
EP0502226A1 (en) * 1991-03-06 1992-09-09 Siemens Aktiengesellschaft Method and apparatus for simulating the currents in an inverter fed rotating field machine
US5969958A (en) * 1995-01-23 1999-10-19 Danfoss Method for measuring phase currents in an inverter
US20060006899A1 (en) * 2004-07-12 2006-01-12 Ronan De Larminat Current sensing in a two-phase motor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111527691A (en) * 2018-01-04 2020-08-11 罗伯特·博世有限公司 Method for operating a synchronous machine
CN111527691B (en) * 2018-01-04 2024-05-14 罗伯特·博世有限公司 Method for operating a synchronous machine

Also Published As

Publication number Publication date
DE102005062759A1 (en) 2007-07-05

Similar Documents

Publication Publication Date Title
WO2007080004A1 (en) Method and device for measuring current
DE102009039672B4 (en) Method for determining the rotor position of a field-oriented synchronous machine
EP0579694A1 (en) Process and circuits for determining machine-related electromagnetic and mechanical state variables on electrodynamic induction machines supplied via converters.
EP3639362B1 (en) Method for determining phase currents of a pwm controlled inverter driven rotating polyphase electric machine
DE102009011674A1 (en) Method for operating electrical machine, involves feeding alternative voltages in one of stator windings, where alternative voltage has multiple voltage impulses
DE102008052933A1 (en) Method for operating an electric motor
EP1820032A1 (en) Method for measuring current using a shunt and measuring current device
EP4186157B1 (en) Parameter identification method for ac machines and control device using the same
DE102013204382A1 (en) Control device and method for driving a rotary field machine
EP3656050B1 (en) Electrical machine
DE1613512C3 (en) Circuit for supplying a rotating field motor
EP2911293A2 (en) Rotating field machine and method for determining the angular position of its rotor
DE102005028605B4 (en) Method for current measurement with a shunt and device for current measurement
DE19828046A1 (en) Brushless DC motor
DE102018206286A1 (en) Method and device for current measurement of an inverter
EP1768253A2 (en) Method and device for messuring current with a shunt
WO2001014897A1 (en) Method and device for measuring the ohmic resistance of a stator circuit of an induction machine
DE102022208793A1 (en) Method for controlling an arrangement with at least one circuit breaker
WO2013068156A2 (en) Method for calibrating a multiphase inverter, operating apparatus, computer program, and computer program product
DE2532356C2 (en) Device for measurement and limit value monitoring of the phase relationship between current and voltage of a three-phase machine connected to a three-phase line
EP3544173A1 (en) Method and device for determining inductivity of an electromagnetic actuator
EP3297153A1 (en) Method and device for determining a position of a rotor of an electronically commutated electrical machine
DE102019208954A1 (en) Method for determining phase currents of an inverter, device and vehicle
DE4435346A1 (en) Operating method for converter-fed permanently excited rotor machine with unipolar stator winding supply
DE102015012450A1 (en) Method for operating an electrical device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase

Ref document number: 06829996

Country of ref document: EP

Kind code of ref document: A1