JP2802322B2 - Impedance measuring device - Google Patents
Impedance measuring deviceInfo
- Publication number
- JP2802322B2 JP2802322B2 JP22685790A JP22685790A JP2802322B2 JP 2802322 B2 JP2802322 B2 JP 2802322B2 JP 22685790 A JP22685790 A JP 22685790A JP 22685790 A JP22685790 A JP 22685790A JP 2802322 B2 JP2802322 B2 JP 2802322B2
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- JP
- Japan
- Prior art keywords
- measured
- impedance
- impedance element
- energy
- voltage
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Fee Related
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- Measurement Of Resistance Or Impedance (AREA)
Description
【発明の詳細な説明】 「産業上の利用分野」 この発明は、被測定インピーダンス素子に正弦波電流
を流し、その被測定インピーダンス素子を流れる電流ま
たはその素子の両端間電圧をベクトル検波して、インピ
ーダンスを測定するインピーダンス測定装置に関する。DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" This invention applies a sinusoidal current to an impedance element to be measured, and performs vector detection of a current flowing through the impedance element to be measured or a voltage between both ends of the element. The present invention relates to an impedance measuring device for measuring impedance.
「従来の技術」 第５図に従来のこの種のインピーダンス測定装置を示
す。方形波発生器11よりの方形波信号が低域通過ろ波器
12を通じて正弦波信号に変換され、その正弦波信号が必
要に応じて増幅器13を通じて被測定インピーダンス素子
14の一端へ供給され、被測定インピーダンス素子14の他
端より流出する電流は電流電圧変換器16で電圧信号に変
換される。その電圧信号は切替スイッチ17を通じて同期
検波回路18,19で方形波発生器11から同相の方形波信号
と、90゜位相がずれた方形波信号とによりそれぞれ同期
検波される。これら同期検波回路18,19の各出力はそれ
ぞれ積分器21,22で積分され、積分器21から同相成分、
つまり実部成分IMrが得られ、積分器22から直交成分、
つまり虚部成分IMmが得られ、これら実部成分Reと虚部
成分Imとがスイッチ23で切替えられてAD変換器24へ供給
され、それぞれデジタル信号に変換され、そのデジタル
信号は演算表示部25へ供給される。FIG. 5 shows a conventional impedance measuring apparatus of this type. The square wave signal from the square wave generator 11 is a low-pass filter.
The sine wave signal is converted to a sine wave signal through 12, and the sine wave signal is
The current supplied to one end of 14 and flowing out from the other end of the measured impedance element 14 is converted into a voltage signal by the current-voltage converter 16. The voltage signal is synchronously detected by the synchronous detection circuits 18 and 19 from the square wave generator 11 through the changeover switch 17 by the square wave signal having the same phase and the square wave signal having a 90 ° phase shift. The outputs of these synchronous detection circuits 18 and 19 are integrated by integrators 21 and 22, respectively.
That is, the real part component I Mr is obtained, and the quadrature component,
That imaginary component I Mm is obtained, these real part component R e and imaginary component I m is supplied is switched by the switch 23 to the AD converter 24, it is converted respectively into a digital signal, the digital signal arithmetic It is supplied to the display unit 25.
一方、被測定インピーダンス素子14の両端の各電圧が
それぞれ高入力インピーダンスのバッファ26,27で取り
出され、これらの電圧差が差回路28で得られ、その差電
圧が切替スイッチ17を通じて同期検波回路18,19へ供給
される。この結果、積分器21から同相成分VMrが、積分
器22から直交成分VMmがそれぞれ得られる。演算表示部2
5で次式で被測定インピーダンス素子14のインピーダン
ス が演算され、この演算結果が表示される。同期検波回路
18,19、積分器21,22でベクトル検波回路29が構成され
る。On the other hand, each voltage at both ends of the impedance element 14 to be measured is taken out by buffers 26 and 27 having high input impedance, and a difference between these voltages is obtained by a difference circuit 28. , 19. As a result, the in-phase component V Mr and the quadrature component V Mm are obtained from the integrator 21 and the integrator 22, respectively. Calculation display section 2
The impedance of the measured impedance element 14 is calculated by Is calculated, and the calculation result is displayed. Synchronous detection circuit
A vector detection circuit 29 is constituted by the integrators 18, 19 and the integrators 21, 22.
「発明が解決しようとする課題」 被測定インピーダンス素子14へ供給する交流電流とし
て比較的大きなものを用いると、被測定インピーダンス
素子14と測定装置との接続治具に数オームの接触抵抗が
ある場合は、その接触抵抗がそこを流れる電流の瞬時値
により変化し、電流波形に歪みを生じ、正弦波でなくな
り、インピーダンス測定は正弦波で測定することが要求
されており、正弦波からずれると、正しい測定を得るこ
とができない。従来においては、この非線形接触抵抗の
ために波形歪が生じて正しい測定値が得られない場合で
も、正しい測定値として表示していた。[Problem to be Solved by the Invention] When a relatively large AC current is supplied to the measured impedance element 14, the connection jig between the measured impedance element 14 and the measuring device has a contact resistance of several ohms. Is that the contact resistance changes according to the instantaneous value of the current flowing therethrough, distorting the current waveform, not being a sine wave, the impedance measurement is required to be measured with a sine wave, and if it deviates from the sine wave, I can't get the right measurements. Conventionally, even when waveform distortion occurs due to the non-linear contact resistance and a correct measured value cannot be obtained, the measured value is displayed as a correct measured value.
「課題を解決するための手段」 請求項１の発明によれば、被測定インピーダンス素子
を流れる電流またはその素子の両端間電圧から、その波
形歪成分を含んだエネルギーが検出され、また上記電流
または電圧から波形歪成分を除去したエネルギーが検出
され、その検出した前者のエネルギーに対する後者のエ
ネルギーの比が求められ、その比が所定値以下の場合は
測定結果は不良とされる。[Means for Solving the Problems] According to the invention of claim 1, energy including a waveform distortion component is detected from a current flowing through an impedance element to be measured or a voltage between both ends of the element. The energy obtained by removing the waveform distortion component from the voltage is detected, and the ratio of the detected former energy to the detected energy is obtained. If the ratio is equal to or less than a predetermined value, the measurement result is determined to be defective.
請求項２の発明によれば、被測定インピーダンス素子
を流れる電流またはその素子の両端間の電圧差からその
波形の歪成分のエネルギーが検出され、この検出エネル
ギーの、被測定インピーダンス素子へ供給する正弦波電
流のエネルギーに対する比が求められ、この比が所定値
以上の場合は測定結果は不良とされる。According to the second aspect of the invention, the energy of the distortion component of the waveform is detected from the current flowing through the impedance element to be measured or the voltage difference between both ends of the element, and the sine of the detected energy supplied to the impedance element to be measured is detected. The ratio of the wave current to the energy is determined. If the ratio is equal to or greater than a predetermined value, the measurement result is determined to be defective.
「実施例」 第１図に請求項１の発明の実施例を第５図と対応する
部分に同一符号を付けて示す。この実施例では切替スイ
ッチ17の出力側に、低域通過ろ波器12の出力正弦波信号
と同一の周波数成分を抽出する低域通過または帯域通過
ろ波器31が分岐接続され、切替スイッチ32で切替スイッ
チ17の出力側とろ波器31の出力側とを切替えて同期検波
回路18,18に接続することができるようにされる。"Embodiment" FIG. 1 shows an embodiment of the first aspect of the present invention, in which parts corresponding to those in FIG. In this embodiment, a low-pass or band-pass filter 31 for extracting the same frequency component as the output sine wave signal of the low-pass filter 12 is branched and connected to the output side of the changeover switch 17, and a changeover switch 32 Thus, the output side of the changeover switch 17 and the output side of the filter 31 are switched to be connected to the synchronous detection circuits 18.
この構成において、被測定インピーダンス素子14が容
量性または抵抗性の場合は、切替スイッチ17を電流電圧
変換器16側に接続し、切替スイッチ32を切替スイッチ17
側に接続して、被測定インピーダンス素子14を流れる電
流の同相成分I1rと、直交成分I1mとを測定する。次に切
替スイッチ32をろ波器31側に接続して、被測定インピー
ダンス素子14を流れる電流中の波形歪成分を除去した同
相成分I2rと、直交成分I2mとを測定する。演算表示部25
はこれら測定値から被測定インピーダンス素子14を流れ
る電流の波形歪成分を含むエネルギーP1＝I1r 2＋I
1m 2と、波形歪成分を除去したエネルギーP2＝I2r 2＋I2m
2とを演算し、さらに、これらエネルギーの比P2/P1を求
め、この比が所定値、例えば0.99以下の場合は歪成分が
多く、正しい測定結果が得られなかったと判定して、そ
のことを演算表示部25に表示する。なお、インピーダン
スの測定は従来と同様に（１）式により求める。ただ
し、外来雑音の影響を避ける点から、IMr,IMm,VMr,VMm
の各測定をろ波器31を通して行うと、再現性がよい測定
結果が得られる。In this configuration, when the measured impedance element 14 is capacitive or resistive, the changeover switch 17 is connected to the current / voltage converter 16 side, and the changeover switch 32 is set to the changeover switch 17.
And measures the in-phase component I 1r and the quadrature component I 1m of the current flowing through the impedance element 14 to be measured. Next, the changeover switch 32 is connected to the filter 31 side, and the in-phase component I 2r from which the waveform distortion component in the current flowing through the measured impedance element 14 has been removed and the quadrature component I 2m are measured. Calculation display section 25
Is the energy P 1 = I 1r 2 + I including the waveform distortion component of the current flowing through the measured impedance element 14 from these measured values.
1m 2 and energy P 2 = I 2r 2 + I 2m from which waveform distortion components have been removed
2 and further, the ratio P 2 / P 1 of these energies is obtained, and when this ratio is a predetermined value, for example, 0.99 or less, the distortion component is large, and it is determined that a correct measurement result was not obtained. This is displayed on the calculation display unit 25. The impedance is measured by the equation (1) as in the conventional case. However, in order to avoid the influence of extraneous noise, I Mr , I Mm , V Mr , V Mm
Is performed through the filter 31, measurement results with good reproducibility can be obtained.
エネルギー比P2/P1が所定値以下か否かの判定はP1,P2
の上位桁の大小を比較して行ってもよい。被測定インピ
ーダンス素子14が誘導性のものの場合は、上記エネルギ
ーを求めるために切替スイッチ17を差回路28側に接続
し、素子14の両端間電圧差について波形歪を含んだ値
と、波形歪を除去した値とを求めて行う。Whether the energy ratio P 2 / P 1 is equal to or less than a predetermined value is determined by P 1 , P 2
May be compared by comparing the magnitude of the high-order digits of. If the measured impedance element 14 is inductive, the changeover switch 17 is connected to the difference circuit 28 side to obtain the above energy, and the voltage difference between both ends of the element 14 includes the value including the waveform distortion and the waveform distortion. This is performed by calculating the removed value.
第２図に請求項１の発明の他の例を示す。この例では
方形波発生器11の代わりにデジタル正弦波発生器33が設
けられ、これよりデジタルの正弦波信号が発生され、そ
のデジタル正弦波信号はDA変換器34でアナログ信号に変
換されて低域通過ろ波器12へ供給される。一方、デジタ
ル正弦波発生器33からデジタルの正弦波信号とデジタル
の余弦波信号とが発生され、それぞれMSB以外のゲート3
5,36へ供給される。MSB以外ゲート35,36は端子37からの
制御信号により、MSB（最上位ビット）以外のビットが
通過または遮断され、つまり全ビットが通過する状態
か、MSBだけが通過する状態かに制御される。MSB以外ゲ
ート35,36の各出力はそれぞれ乗算形DA変換器38,39へ供
給され、アナログ信号に変換されると共にそれぞれ切替
スイッチ17の出力と掛算される。乗算形DA変換器38,39
の各出力はそれぞれ積分器21,22へ供給される。FIG. 2 shows another example of the first aspect of the present invention. In this example, a digital sine wave generator 33 is provided instead of the square wave generator 11, and a digital sine wave signal is generated from the digital sine wave signal. It is supplied to the band-pass filter 12. On the other hand, a digital sine wave signal and a digital cosine wave signal are generated from the digital sine wave
Supplied to 5,36. The gates 35 and 36 other than the MSB are controlled by a control signal from the terminal 37 so that bits other than the MSB (most significant bit) are passed or cut off, that is, whether all bits pass or only the MSB passes. . The respective outputs of the gates 35 and 36 other than the MSB are supplied to multiplying DA converters 38 and 39, respectively, converted into analog signals, and multiplied by the outputs of the changeover switches 17, respectively. Multiplying DA converters 38, 39
Are supplied to integrators 21 and 22, respectively.
MSB以外ゲート35,36からMSBビットのみを出力させる
と、０゜位相の方形波信号と90゜位相の方形波信号とに
より、切替スイッチ17の出力を乗算形DA変換器38,38で
それぞれ同期検波した状態になり、第１図の場合におけ
る波形歪成分を含んだ電流値I1r,I1mを求めることがで
きる。MSB以外ゲート35,36から全ビットを出力させる
と、切替スイッチ17の出力に正弦波信号、余弦波信号を
それぞれ乗算し、フーリエ積分がなされ、波形歪成分を
除去した電流値I2r,I2mを求めることができる。従っ
て、演算表示部25で第１図の場合と同様に処理して測定
結果が正しいか否かを判定表示することができる。測定
結果を得る時、MSB以外ゲート35,36は全ビットを通過
させる。When only the MSB bit is output from the gates 35 and 36 except the MSB, the output of the changeover switch 17 is synchronized by the multiplying DA converters 38 and 38 by the square wave signal of 0 ° phase and the square wave signal of 90 ° phase, respectively. In the detection state, the current values I 1r and I 1m including the waveform distortion components in the case of FIG. 1 can be obtained. When the output all bits from gate 35 and 36 other than MSB, sine wave signal, a cosine-wave signal is multiplied to the output of the switch 17, the Fourier integral is performed, the current value I 2r removing the waveform distortion component, I 2m Can be requested. Therefore, it is possible to determine and display whether or not the measurement result is correct by performing the same processing as in the case of FIG. When obtaining the measurement result, the gates 35 and 36 pass all bits except the MSB.
波形歪にもとづく測定結果の良否を判定する手段をベ
クトル検波回路29と別個に設けてもよい。例えば第３図
にその測定結果の良否を判定する部分のみを示すよう
に、第１図における電流電圧変換器16の出力は分岐され
て２乗回路41とろ波器42とへ供給され、２乗回路41で波
形歪を含む電流が２乗され、その出力が積分器43で積分
され、ルートミーンスケア値、つまり波形歪成分を含む
電流のエネルギーが得られる。一方、ろ波器42で基本波
成分のみが取り出され、その出力が２乗回路44で２乗さ
れ、その２出力が積分器45で積分され、つまり波形歪成
分が除去された電流のエネルギーが得られ、これと積分
器43の出力とが比較器46で比較され、その有効桁以上が
比較され、積分器43の出力に対し積分器45の出力の比が
所定値以下か否かが検出される。Means for determining the quality of the measurement result based on the waveform distortion may be provided separately from the vector detection circuit 29. For example, the output of the current-voltage converter 16 in FIG. 1 is branched and supplied to a squaring circuit 41 and a filter 42, as shown in FIG. The current including the waveform distortion is squared by the circuit 41, and the output is integrated by the integrator 43 to obtain the root mean care value, that is, the energy of the current including the waveform distortion component. On the other hand, only the fundamental wave component is taken out by the filter 42, the output is squared by the squaring circuit 44, and the two outputs are integrated by the integrator 45, that is, the energy of the current from which the waveform distortion component is removed is obtained. The output of the integrator 43 is compared with the output of the integrator 43, and the number of significant digits or more is compared by the comparator 46. It is detected whether the ratio of the output of the integrator 45 to the output of the integrator 43 is equal to or less than a predetermined value. Is done.
第４図に請求項２の発明の実施例の要部を示す。増幅
器13の出力の一部が分岐されて２乗回路47へ供給され、
その２乗回路47の出力は積分器48で積分され、入力正弦
波電流のエネルギーが得られる。また電流電圧変換器16
の出力が分岐されてノッチフィルタ49へ供給され、ノッ
チフィルタ49で、基本波、つまり増幅器13の出力正弦波
信号の周波数成分のみが遮断され、他の成分、つまり波
形歪成分のみが通過され、その出力は２乗回路51で２乗
され、その２乗回路51の出力は積分器52で積分され、波
形歪成分のエネルギーが得られる。積分器48の出力に対
する積分器52の出力の比が比較器53でとられ、その比が
所定値より大の場合は、その時の測定結果は不良と判定
される。FIG. 4 shows a main part of an embodiment of the second aspect of the present invention. A part of the output of the amplifier 13 is branched and supplied to the squaring circuit 47,
The output of the squaring circuit 47 is integrated by the integrator 48 to obtain the energy of the input sine wave current. In addition, the current-voltage converter 16
Is supplied to the notch filter 49, and the notch filter 49 blocks only the fundamental wave, that is, the frequency component of the output sine wave signal of the amplifier 13, and passes only the other components, that is, only the waveform distortion component. The output is squared by a squaring circuit 51, and the output of the squaring circuit 51 is integrated by an integrator 52 to obtain energy of a waveform distortion component. The ratio of the output of the integrator 52 to the output of the integrator 48 is calculated by the comparator 53. If the ratio is greater than a predetermined value, the measurement result at that time is determined to be defective.
第３図、第４図の例においても、被測定インピーダン
ス素子を流れる電流から測定結果の良否を求めたが、被
測定インピーダンス素子14が誘導性の場合は被測定イン
ピーダンス素子の両端間電圧から同様の処理により測定
結果の良否を求めるようにすることもできる。3 and 4, the quality of the measurement result was determined from the current flowing through the measured impedance element. However, when the measured impedance element 14 was inductive, the same was determined from the voltage between both ends of the measured impedance element. The quality of the measurement result can be determined by the above processing.
「発明の効果」 以上述べたように、この発明によれば被測定インピー
ダンス素子を流れる電流またはその両端間電圧から、波
形歪が大きく、正しい測定が得られない状態を判定し、
その判定が得られると測定結果が正しいものでないこと
が表示され、誤った測定結果を得るおそれはなく、また
測定結果不良と表示された場合は、被測定インピーダン
ス素子自体の不良、またはこれと測定装置との接続不良
ではないかをチェックし、正しい測定をすることが可能
となる。[Effects of the Invention] As described above, according to the present invention, from the current flowing through the impedance element to be measured or the voltage between both ends thereof, the waveform distortion is large, and it is determined that a correct measurement cannot be obtained.
When the judgment is obtained, it is displayed that the measurement result is not correct, and there is no risk of obtaining an incorrect measurement result.If the measurement result is displayed as bad, if the measured impedance element itself is defective, or the measurement is not performed. It is possible to check whether there is a connection failure with the device and perform a correct measurement.
第１図は請求項１の発明の実施例を示すブロック図、第
２図はその他の例を示すブロック図、第３図はそのさら
に他の例の要部を示すブロック図、第４図は請求項２の
発明の実施例の要部を示すブロック図、第５図は従来の
インピーダンス測定装置を示すブロック図である。FIG. 1 is a block diagram showing an embodiment of the first aspect of the present invention, FIG. 2 is a block diagram showing another example, FIG. 3 is a block diagram showing a main part of still another example, and FIG. FIG. 5 is a block diagram showing a main part of a second embodiment of the invention, and FIG. 5 is a block diagram showing a conventional impedance measuring device.
Claims (2)
流し、その被測定インピーダンス素子を流れる電流また
はその素子の両端間電圧をベクトル検波して上記被測定
インピーダンス素子のインピーダンスを求めるインピー
ダンス測定装置において、 上記被測定インピーダンス素子を流れる電流またはその
素子の両端間電圧からその波形歪成分も含むエネルギー
を検出する手段と、 上記被測定インピーダンス素子を流れる電流またはその
素子の両端間電圧からその波形歪成分を除去したエネル
ギーを検出する手段と、 これら両検出エネルギーの前者に対する後者の比を求め
る手段と、 その比が所定値以下で測定結果を不良とする手段と、 を設けたことを特徴とするインピーダンス測定装置。1. An impedance measuring apparatus for applying a sine wave current to an impedance element to be measured and vector-detecting a current flowing through the impedance element to be measured or a voltage across the element to obtain an impedance of the impedance element to be measured. Means for detecting energy including a waveform distortion component from a current flowing through the impedance element to be measured or a voltage between both ends of the element; and a waveform distortion component from the current flowing through the impedance element to be measured or a voltage between both ends of the element. Means for detecting the removed energy, means for determining the ratio of the latter to the former of both detected energies, and means for making the measurement result defective when the ratio is equal to or less than a predetermined value. apparatus.
流し、その被測定インピーダンス素子を流れる電流また
はその素子の両端間電圧をベクトル検波して上記被測定
インピーダンス素子のインピーダンスを求めるインピー
ダンス測定装置において、 上記被測定インピーダンス素子を流れる電流またはその
素子の両端間電圧からその波形の歪成分のエネルギーを
検出する手段と、 そのエネルギーの、上記正弦波電流のエネルギーに対す
る比を求める手段と、 その比が所定値以上で測定結果を不良とする手段と、 を設けたことを特徴とするインピーダンス測定装置。2. An impedance measuring apparatus for applying a sine wave current to an impedance element to be measured and vector-detecting a current flowing through the impedance element to be measured or a voltage between both ends of the element to obtain an impedance of the impedance element to be measured. Means for detecting the energy of the distortion component of the waveform from the current flowing through the impedance element to be measured or the voltage between both ends of the element; means for calculating the ratio of the energy to the energy of the sine-wave current; Means for making the measurement result inferior when the value is greater than or equal to a value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22685790A JP2802322B2 (en) | 1990-08-29 | 1990-08-29 | Impedance measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22685790A JP2802322B2 (en) | 1990-08-29 | 1990-08-29 | Impedance measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04109174A JPH04109174A (en) | 1992-04-10 |
| JP2802322B2 true JP2802322B2 (en) | 1998-09-24 |
Family
ID=16851659
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22685790A Expired - Fee Related JP2802322B2 (en) | 1990-08-29 | 1990-08-29 | Impedance measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2802322B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102237741B1 (en) | 2020-03-02 | 2021-04-07 | 숙명여자대학교산학협력단 | Simultaneous Measurement System of Luminance, Impedance, and Noise Characteristics of Light Emitting Devices in real time |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7260481B1 (en) * | 2006-03-17 | 2007-08-21 | Tanita Corporation | Vector detecting device and living-body complex impedance measuring apparatus having the vector detecting device |
| JP2011163838A (en) * | 2010-02-08 | 2011-08-25 | Hioki Ee Corp | Measuring apparatus and measuring method |
| JP6589613B2 (en) * | 2015-12-10 | 2019-10-16 | いすゞ自動車株式会社 | Reactance measuring device |
| CN109374971B (en) * | 2018-09-25 | 2020-12-04 | 北京工业大学 | Megahertz impedance meter based on embedded system |
| JP7226147B2 (en) * | 2019-07-04 | 2023-02-21 | 株式会社デンソー | battery monitor |
-
1990
- 1990-08-29 JP JP22685790A patent/JP2802322B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102237741B1 (en) | 2020-03-02 | 2021-04-07 | 숙명여자대학교산학협력단 | Simultaneous Measurement System of Luminance, Impedance, and Noise Characteristics of Light Emitting Devices in real time |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04109174A (en) | 1992-04-10 |
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