WO2020026618A1 - Dispositif de détection de courant électrique - Google Patents

Dispositif de détection de courant électrique Download PDF

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Publication number
WO2020026618A1
WO2020026618A1 PCT/JP2019/024006 JP2019024006W WO2020026618A1 WO 2020026618 A1 WO2020026618 A1 WO 2020026618A1 JP 2019024006 W JP2019024006 W JP 2019024006W WO 2020026618 A1 WO2020026618 A1 WO 2020026618A1
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WIPO (PCT)
Prior art keywords
power semiconductor
input
detection device
current detection
integrator
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PCT/JP2019/024006
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English (en)
Japanese (ja)
Inventor
政光 稲葉
正浩 長洲
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株式会社日立パワーデバイス
独立行政法人国立高等専門学校機構
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Publication of WO2020026618A1 publication Critical patent/WO2020026618A1/fr

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    • 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
    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present invention relates to a current detection device.
  • Patent Document 1 Japanese Patent Application Laid-Open No. H11-157, pp. 1-5 describes a [[Problem] a current detection device capable of accurately detecting a current flowing through a switching element by eliminating an error due to a resistance component parasitic on a wiring, and a semiconductor device using the same.
  • the integrator 12 integrates the voltage to detect a current flowing through the wiring of the switching element. " ing. There is also a method in which a current is detected by a current detection device for each of the modules connected in parallel, integrated by an integrator, and then added.
  • the current detection device of the technology disclosed in Patent Document 1 is a technology for detecting the current of a single semiconductor device, and has a problem (problem) that it is not suitable for detecting the currents of a plurality of semiconductor devices. .
  • a method is considered in which this technology for detecting the current of a single semiconductor device is applied, the currents of a plurality of semiconductor devices are detected, integrated, and then added.
  • this method has a problem (problem) that a plurality of integrators are required, the circuit becomes complicated, and the cost is increased.
  • the present invention has been made in view of the above-described problem.
  • the current detection of a plurality of semiconductor devices is collectively performed by utilizing the inductance of wiring. It is an object (object) to provide a current detection device which performs the current detection.
  • the current detection device of the present invention includes a plurality of input resistors each having one end connected to the wiring of the plurality of power semiconductor modules and the other end connected to one point at the input connection point, and the input connection point and the ground. It is characterized by comprising an addition resistor connected therebetween, and an integrator for integrating a voltage between both ends of the addition resistor. Other means will be described in the embodiments for carrying out the invention.
  • a current detection device that collectively detects currents of a plurality of semiconductor devices (power semiconductor devices) by utilizing wiring inductance when a plurality of semiconductor devices are connected in parallel. it can.
  • FIG. 2 is a diagram illustrating a configuration example of a current detection device according to the first embodiment of the present invention, and is a diagram illustrating a connection relationship with a power semiconductor device (power semiconductor module).
  • FIG. 7 is a diagram illustrating a configuration example of a current detection device according to a second embodiment of the present invention, and is a diagram illustrating a connection relationship with a power semiconductor device (power semiconductor module).
  • FIG. 3 is a diagram illustrating a configuration example of an integrator in the current detection device according to the first embodiment of the present invention.
  • FIG. 1 is a diagram illustrating a configuration example of a current detection device 10 according to a first embodiment of the present invention, and is a diagram illustrating a connection relationship with a power semiconductor device 300 (power semiconductor modules 301 to 30n).
  • the currents flowing through the n wires of the power semiconductor device 300 (power semiconductor modules 301 to 30n) are added (voltage adder 11) and integrated (integrator 12) by the current detection device 10 to obtain the current (I 1, I 2, ⁇ , detecting the current I is the sum of I n).
  • a current detection device 10 includes a voltage adder (voltage addition circuit) 11 and an integrator (integration circuit) 12.
  • the voltage adder 11 includes n input resistances (R i ) 111 to 11n and an addition resistance (R o ) 120.
  • One ends of the n input resistors (R i ) 111 to 11n are connected to one ends of wirings of n power semiconductor modules 301 to 30n to be described later.
  • the other ends of the n input resistors (R i ) 111 to 11n are connected to each other at an input connection point P100.
  • the addition resistance (R o ) 120 is connected between the input connection point P100 and the ground G.
  • the integrator 12 receives the voltage V add across the addition resistor (R o ) 120 and integrates the voltage V add .
  • the power semiconductor device 300 is configured by connecting n power semiconductor modules 301 to 30n in parallel.
  • the power semiconductor modules 301 to 30n are represented by switching elements (301 to 30n).
  • the power semiconductor modules 301 to 30n have components other than the switching elements, but detailed notations are omitted for convenience of description (simplification).
  • the power semiconductor device 300 has components (for example, a control circuit) other than the power semiconductor modules 301 to 30n, but detailed description is omitted for convenience (simplification) of the description.
  • Each of the n power semiconductor modules 301 to 30n has a wiring between itself and the ground G. Each wiring has parasitic wiring inductance and wiring resistance.
  • the n power semiconductor modules 301 to 30n have switching elements (301 to 30n) and periodically perform on / off (ON / OFF) operations. By this on / off operation, a noise-like voltage due to the wiring inductance and the wiring resistance is generated between the grounds G of the power semiconductor modules 301 to 30n.
  • the effect of the wiring inductance is actually primarily dominant than the effect of the wiring resistance, so only the effect of the wiring inductance will be considered below.
  • This wiring inductance is denoted by L in FIG. Wiring is provided from one end of each of the wiring inductances L to one end of each of the n input resistors (R i ) 111 to 11n for extracting a signal.
  • n-number of input resistance at voltage adder 11 (R i) 111 each current flowing through the ⁇ 11n i 1, i 2, ⁇ , and i n. Further, the current flowing through the summing resistor (R o) 120 and a current I o. Further, the voltage generated across the summing resistor (R o) 120 and voltage V the add.
  • a plurality of wirings of the power semiconductor modules 301 to 30n have parasitic wiring inductance L and wiring resistance.
  • the wiring resistance is small, and the time variation of the current in the wiring inductance L is very large, so that V 1 , V 2 ..., V n and i L1 , i L2 ,. , The following relational expression holds.
  • Equation (6) is written as shown in the following equation (7) using the symbolic j ⁇ .
  • j is an imaginary unit.
  • the frequency f included in ⁇ (2 ⁇ f) is assumed to be a main frequency in a frequency component of a voltage generated in the wiring inductance L in a transition period when the switching elements of the power semiconductor modules 301 to 30n are turned on (ON).
  • the inductive reactance determined by the frequency f and the wiring inductance L is ⁇ L.
  • equation (6) is represented by equation (7).
  • Expression (16) if there is a relationship of Expression (17), Expression (16) can be approximated to Expression (18).
  • equation (19) The meaning of equation (19) will be described.
  • the integral on the right side of the equation (19) integrates V add , and it can be seen that the current I flowing through the power semiconductor device 300 is calculated from the output of the integrator 12 shown in FIG. In other words, this shows that the current I flowing through the power semiconductor device 300 (the power semiconductor modules 301 to 30n) can be detected all at once by the current detection device 10 shown in FIG.
  • the right side of the expression (19) includes (n + 1) and L as coefficients. Since n is the number n of the power semiconductor modules 301 to 30n, it is a known value. Since the wiring inductance L is the inductance of a known wiring, the wiring inductance L is generally also known. Therefore, the value of the current I flowing through the power semiconductor device 300 can be determined from Equation (19). Further, even if the wiring inductance L is not known, the current value can be relatively compared, so that an abnormality of the switching element (power semiconductor module) can be detected, and the power semiconductor device including the switching element can be detected. It can be used for generating a timing signal and the like when controlling the power semiconductor module 300 (power semiconductor modules 301 to 30n).
  • FIG. 3 is a diagram illustrating a configuration example of an integrator in the current detection device 10 according to the first embodiment of the present invention.
  • the integrator 12 includes an operational amplifier 121, a resistor (R) 122, and a capacitor (C) 123.
  • the first terminal of the capacitor 123 is connected to the output terminal S O of the operational amplifier 121.
  • the second terminal of the capacitor 123 is connected to the first terminal of the resistor 122 and to the inverting input terminal (-) of the operational amplifier 121.
  • the non-inverting input terminal (+) of the operational amplifier 121 is connected to the ground G.
  • the second terminal of the resistor 122 is connected to the input terminal S I. Voltage signal input to the input terminal S I is integrated by integrator 12, is output from the output terminal S O.
  • the integrator 12 Since the integrator 12 having the above configuration is generally well known as an integrator using the operational amplifier 121, a detailed description of the operation principle will be omitted. Although not shown in FIGS. 3 and 1, the integrator 12 is provided with a resetting circuit (reset device), and the integrator 12 is used after being reset every one cycle (one time). . That is, the power semiconductor device 300 (power semiconductor modules 301 to 30n) in FIG. 1 performs an on / off (ON / OFF) operation at a predetermined frequency. When performing the ON operation, the integrator 12 performs the integration operation, but resets the integrator 12 in a section where the power semiconductor modules 301 to 30n are OFF.
  • the power semiconductor device 300 power semiconductor modules 301 to 30n
  • the integrator 12 When performing the ON operation, the integrator 12 performs the integration operation, but resets the integrator 12 in a section where the power semiconductor modules 301 to 30n are OFF.
  • a current detection device that collectively detects currents of a plurality of power semiconductor modules by utilizing wiring inductance when a plurality of power semiconductor modules are connected in parallel.
  • the current detection device not only calculates the total current value of the plurality of power semiconductor modules, but also detects an abnormality of the power semiconductor module and a timing signal for controlling the power semiconductor device including the power semiconductor module. And so on.
  • FIG. 2 is a diagram illustrating a configuration example of a current detection device 20 according to a second embodiment of the present invention, and is a diagram illustrating a connection relationship with a power semiconductor device 300 (power semiconductor modules 301 to 30n).
  • the power semiconductor device 300 power semiconductor modules 301 to 30n
  • the power semiconductor device 300 is the same as the power semiconductor device 300 (power semiconductor modules 301 to 30n) of the first embodiment shown in FIG. Description is omitted.
  • the current detection device 20 includes a voltage adder (voltage addition circuit) 21 and an integrator (integration circuit) 12.
  • the integrator 12 in FIG. 2 is the same as the integrator 12 in FIG.
  • the voltage adder 21 includes n first input resistors (r 1 ) 211 to 21 n, n second input resistors (r 2 ) 221 to 22 n, a twisted pair cable (Twisted pair cable) 23, summing resistor and a (R o) 120.
  • One ends of the n first input resistors (r 1 ) 211 to 21n are connected to one ends of wirings of the n power semiconductor modules 301 to 30n, respectively.
  • the other ends of the n first input resistors (r 1 ) 211 to 21n are connected to one ends of n pairs of signal lines of the twisted pair cable 23, respectively.
  • each of the n pairs of twisted wires of the twisted pair cable 23 is connected to one end of each of the n second input resistors (r 2 ) 221 to 22n.
  • the twisted pair cable 23 has at least n pairs of twisted pairs.
  • One of the stranded wires is connected to the other end of the n first input resistors (r 1 ) 211 to 21n and to one end of the n second input resistors (r 2 ) 221 to 22n, respectively.
  • the other one of the n pairs of stranded wires is connected to the ground (G).
  • the other ends of the n second input resistors (r 2 ) 221 to 22n are connected to each other at an input connection point P200.
  • Summing resistor (R o) 120 is connected between an input connection point P200 and the ground G.
  • the integrator 12 receives the voltage V add across the addition resistor (R o ) 120 and integrates the voltage V add .
  • the difference between the circuit configuration of FIG. 2 and the circuit configuration of FIG. 1 is that the n input resistors (R i ) 111 to 11n in FIG. 1 )
  • the configuration is replaced with the configuration of 211 to 21n, n second input resistors (r 2 ) 221 to 22n, and the twisted pair cable 23.
  • This configuration prevents noise from being mixed into signal wiring for transmitting a signal when the current detection device 20, particularly the integrator 12, is installed at a position away from the power semiconductor device 300 (power semiconductor modules 301 to 30n).
  • a twisted pair cable 23 is used.
  • the voltages generated in the wiring inductances L of the n power semiconductor modules 301 to 30n are denoted by V 1 , V 2 ,..., V n , respectively.
  • the above description is based on the currents i L1 , i L2 ,..., I Ln flowing through the wiring inductance L of the n power semiconductor modules 301 to 30n in FIG. 1 showing the first embodiment, and the n power semiconductor modules 301 to 30n.
  • voltage V 1, V 2 generated in wiring inductance L of, ..., is the same as V n.
  • n first input resistors (r 1 ) 211 to 21 n and the n second input resistors (r 2 ) 221 to 22 n in the voltage adder 21 are represented by i 1 , i 2 ,. ⁇ , and i n.
  • the current on the input side and the current on the output side of the twisted pair cable 23 are i 1 , i 2 ,..., I, respectively, in the currents flowing through the n pairs of twisted pair signal lines. n .
  • Summing resistor (R o) 120 is connected between an input connection point P200 and the ground G. Further, the current flowing through the summing resistor (R o) 120 and a current I o. Further, the voltage generated across the summing resistor (R o) 120 and voltage V the add.
  • the integrator 12 receives the voltage V add across the addition resistor (R o ) 120 and integrates the voltage V add .
  • the circuit configuration of FIG. 2 differs from the circuit configuration of FIG. 1 in that n input resistors (R i ) 111 to 11n in FIG. That is, the configuration is replaced with the configuration of the twisted pair cable 23 with the resistors (r 1 ) 211 to 21n, the n second input resistors (r 2 ) 221 to 22n. That is, in FIG. 2, the n input resistors (R i ) 111 to 11n in FIG.
  • Twisted pair cable 23 replaces n first input resistors (r 1 ) 211 to 21n and n second input resistors (r 2 ) Twisted pair cable 23 replaces n first input resistors (r 1 ) 211 to 21n and n second input resistors (r 2 ) 221 to 22n separately with 221 to 22n. It is connected. That is, when the current detection device 20 (especially, the integrator 12) is installed at a position away from the power semiconductor device 300 (power semiconductor modules 301 to 30n) for, for example, an arrangement reason, the twisted pair cable 23 is used. Therefore, it is configured such that noise hardly gets on the signal wiring through which the signal is transmitted.
  • the relationship among the addition resistor (R o ) 120, the integrator 12, and the power semiconductor device 300 (power semiconductor modules 301 to 30n) is the same as in the first embodiment (FIG. 1). It is. Therefore, also in the second embodiment, the following equation (24) similar to the equation (19) is obtained. Note that the transformation and derivation of the equations (13) to (18) in the first embodiment are the same in the second embodiment (FIG. 2), and thus redundant description will be omitted.
  • the first input resistance (r 1 ) has a value close to the characteristic impedance of the twisted pair cable 23 in order to prevent reflection at the time of input to the twisted pair cable 23. It is desirable to use.
  • the total value of the second input resistance (r 2 ) and the addition resistance (R o ) also has a value close to the characteristic impedance of the twisted pair cable 23 in order to prevent ringing at the output end of the twisted pair cable 23. It is desirable to use.
  • the condition for preventing reflection when inputting to the twisted pair cable 23 is as follows.
  • the condition of the second input resistance (r 2 ) is not as strict as the input resistance (r 1 ).
  • the resistance value of the summing resistor (R o) is set smaller than the input impedance of the integrator 12.
  • the inductive reactance of the module wiring of the power semiconductor module is ⁇ L, that is, 2 ⁇ fL.
  • L and f if the power semiconductor module and module wiring to be used are determined, the wiring inductance L and the approximate value and range of the main frequency f in the transient response when the power semiconductor module is turned on can be grasped, and thus can be handled as known. .
  • the use of the summing resistor R o satisfying more of the conditions increases the accuracy of the current detection device 10.
  • the addition resistance Ro is set smaller than the input impedance of the integrator.
  • FIG. 3 is shown as an example of the integrator, it is not limited to the circuit of FIG. An integrator not using an operational amplifier may be used. Also, a high-pass filter (high-pass filter) is provided before the integrator. Alternatively, there is a method in which the integrator itself has a function of emphasizing integration of a high frequency. In this case, in the relationship between the wiring inductance (L) and the wiring resistance (not shown) in the wiring of the power semiconductor modules 301 to 30n, the influence of an error due to a resistance component parasitic on the wiring can be reduced, and the current I can be further reduced. This has the effect of being able to calculate accurately.
  • L wiring inductance
  • the wiring resistance not shown
  • the integrator 12 mainly integrates a transient response current when the switching elements (301 to 30n) of the power semiconductor device 300 (power semiconductor modules 301 to 30n) are turned on. Therefore, there is a method of providing a device (circuit) for determining the magnitude of the voltage V add which is the voltage between both ends of the addition resistor, and operating the integrator 12 when the voltage V add exceeds a predetermined voltage. With this method, the current I can be calculated more accurately. As described above, when the power semiconductor device 300 (the power semiconductor modules 301 to 30n) is performing the ON operation, the integrator 12 performs the integration operation, but the section in which the power semiconductor modules 301 to 30n are OFF. , The integrator 12 is reset.
  • the twisted pair cable 23 has been described as being used for the voltage adder 21 of the current detection device 20 according to the second embodiment.
  • the purpose of this twisted pair cable 23 is to prevent noise generated in an environment where the current detection device 20 is installed from affecting the signal. Therefore, the present invention is not limited to a “twisted pair cable” as long as the influence of noise is eliminated.
  • a paired wire that does not have a cable shape may be used.
  • a plurality of coaxial cables may be used.
  • the power semiconductor device 300 having a plurality of power semiconductor modules in parallel has been described, but the current measurement is not limited to the power semiconductor module (semiconductor module).
  • a device that uses general electricity as a power source and connects a plurality of loads in parallel is also an object.
  • a plurality of power semiconductor devices on which a plurality of power semiconductor modules are mounted are combined as a power semiconductor module.
  • the switching elements are represented by MOSFET (Metal Oxide Semiconductor Field Effect Transistor) symbols as representatives of the power semiconductor modules 301 to 30n.
  • MOSFET Metal Oxide Semiconductor Field Effect Transistor
  • the switching element is not limited to the MOSFET.
  • an IGBT Insulated Gate Bipolar Transistor
  • a super junction MOSFET may be used.
  • Wiring inductance L In FIG. 1, all the wiring inductances L of the power semiconductor modules 301 to 30n are uniformly described as L. In the description of the current detection device 10 according to the first embodiment, the wiring inductance L is uniformly represented as L in Expressions (6) and (7). However, they need not be the same. Even if there is variation in the wiring inductance L, it is possible to detect the variation within an error range. Further, even if there is an error, an abnormality of the power semiconductor device 300 (the power semiconductor modules 301 to 30n) can be detected.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Current Or Voltage (AREA)
  • Power Conversion In General (AREA)

Abstract

L'invention concerne un dispositif de détection de courant électrique qui détecte collectivement des courants électriques d'une pluralité de dispositifs à semi-conducteurs (dispositifs à semi-conducteurs de puissance) en utilisant une inductance du câblage, la détection étant mise en œuvre lorsque la pluralité de dispositifs à semi-conducteurs est connectée en parallèle. La présente invention comprend : une pluralité de résistances d'entrée (111-11n) présentant une extrémité connectée respectivement au câblage d'une pluralité de modules à semi-conducteurs de puissance (301-30n) et les autres extrémités mutuellement connectées à un point unique au niveau d'un point de connexion d'entrée (P100) ; une résistance de sommation (120) connectée entre le point de connexion d'entrée (P100) et le sol (G) ; et un intégrateur (12) qui intègre la tension aux deux extrémités de la résistance de sommation (120).
PCT/JP2019/024006 2018-07-31 2019-06-18 Dispositif de détection de courant électrique WO2020026618A1 (fr)

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JP2018143039A JP7007672B2 (ja) 2018-07-31 2018-07-31 電流検出装置
JP2018-143039 2018-07-31

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10323016A (ja) * 1997-05-14 1998-12-04 Fuji Electric Co Ltd 電力変換装置のデバイス定常電流バランス制御回路
JP2017122631A (ja) * 2016-01-07 2017-07-13 株式会社 日立パワーデバイス 電流検出装置及びそれを用いた半導体装置

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10323016A (ja) * 1997-05-14 1998-12-04 Fuji Electric Co Ltd 電力変換装置のデバイス定常電流バランス制御回路
JP2017122631A (ja) * 2016-01-07 2017-07-13 株式会社 日立パワーデバイス 電流検出装置及びそれを用いた半導体装置

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