JPH095368A - Method for measuring resistance of wiring - Google Patents
Method for measuring resistance of wiringInfo
- Publication number
- JPH095368A JPH095368A JP7149804A JP14980495A JPH095368A JP H095368 A JPH095368 A JP H095368A JP 7149804 A JP7149804 A JP 7149804A JP 14980495 A JP14980495 A JP 14980495A JP H095368 A JPH095368 A JP H095368A
- Authority
- JP
- Japan
- Prior art keywords
- winding
- voltage
- resistance
- power supply
- current
- 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.)
- Pending
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- Measurement Of Resistance Or Impedance (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、変圧器巻線など鉄心を
有する巻線の抵抗を測定する方法、特に鉄心の磁気飽和
によってインダクタンスを無視できる形で測定する方法
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of measuring the resistance of a winding having an iron core such as a transformer winding, and more particularly to a method of measuring the inductance in a negligible form due to magnetic saturation of the iron core.
【０００２】[0002]
【従来の技術】変圧器巻線抵抗の測定は、直流電圧降下
法などにより、測定端子以外は全て開放して行ってい
る。その場合、インダクタンスの影響を除去するため
に、計器の指示が一定となった後に指示値を読み取る。
測定時の回路を図３に、その等価回路を図４に示す。図
中、１１は直流電源（電圧値Ｅ）、１２はスイッチ、１
３は測定対象の変圧器、１３Ｐは変圧器１３の一次巻
線、１３Ｓは変圧器１３の二次巻線、１３ＰＲは一次巻
線１３Ｐの直流抵抗分（抵抗値Ｒ）、１３ＰＬは一次巻
線１３Ｐのインダクタンス分（インダクタンスＬ）であ
る。スイッチ１２の投入時に回路に流れる電流Ｉは、2. Description of the Related Art The resistance of a transformer winding is measured by a DC voltage drop method or the like except for the measurement terminals. In that case, in order to eliminate the influence of the inductance, the indication value is read after the indication on the meter becomes constant.
The circuit at the time of measurement is shown in FIG. 3, and its equivalent circuit is shown in FIG. In the figure, 11 is a DC power supply (voltage value E), 12 is a switch, 1
3 is a transformer to be measured, 13P is a primary winding of the transformer 13, 13S is a secondary winding of the transformer 13, 13PR is a DC resistance component (resistance value R) of the primary winding 13P, and 13PL is a primary winding. It is an inductance component (inductance L) of 13P. The current I flowing through the circuit when the switch 12 is turned on is
【０００３】[0003]
【数１】 [Equation 1]
【０００４】となり、図５のように表される。変圧器の
場合、Ｌ≫Ｒであるため、一定電流に達するまでに長い
時間が必要である。このため、変圧器の鉄心を飽和さ
せ、インダクタンスを無視できるようにして測定する方
法（磁気飽和法）を採用することにより、測定時間の短
縮を図っている。この方法でも、変圧器巻線の特殊性を
考慮する必要がある。それは、鉄心に使用しているけい
素鋼板の磁気特性に関係する。けい素鋼板は、図６のよ
うな透磁率特性を有しており、一定電圧を加えた時の電
流−時間特性は図７のようになる。従って、最高透磁率
を越えなければ、磁気飽和に必要な電流を流すことはで
きない。And is represented as shown in FIG. In the case of a transformer, since L >> R, it takes a long time to reach a constant current. For this reason, the measurement time is shortened by adopting a method (magnetic saturation method) of saturating the iron core of the transformer so that the inductance can be ignored. This method also requires consideration of the peculiarities of the transformer winding. It is related to the magnetic properties of the silicon steel sheet used for the iron core. The silicon steel sheet has magnetic permeability characteristics as shown in FIG. 6, and current-time characteristics when a constant voltage is applied are as shown in FIG. Therefore, the current required for magnetic saturation cannot be passed unless the maximum magnetic permeability is exceeded.
【０００５】鉄心を有する巻線の抵抗測定時の回路を図
８に示す。巻線２３は、直流抵抗分２３Ｒとインダクタ
ンス分２３Ｌを持つものとする。この回路で印加電圧を
Ｅとした場合と、その２倍の２Ｅとした場合の電流−時
間特性を図９に示す。この特性から明らかなように印加
電圧を大きくすると、最高透磁率を越える時間が早くな
る。この点に着目して図１０，図１１に示す巻線抵抗測
定回路が考案されている。図１０は、可変電圧直流電源
２１を用い、スイッチ２２の投入時に高電圧、一定時間
後に低電圧とするものである。図１１は、高めの電圧の
直流電源２６を用い、測定回路に外部抵抗２４を設ける
とともに、これに並列にバイパス用のスイッチ２５を接
続して、測定開始時にはスイッチ２５を閉じ、一定時間
後にスイッチ２５を開いて一定飽和電流を得るものであ
る。いずれの場合にも、図１２に示すように早い時点ｔ
1で一定飽和電流となる電流−時間特性が得られる。FIG. 8 shows a circuit for measuring resistance of a winding having an iron core. The winding wire 23 has a DC resistance component 23R and an inductance component 23L. FIG. 9 shows the current-time characteristics when the applied voltage in this circuit is E and when it is twice that, 2E. As is clear from this characteristic, when the applied voltage is increased, the time for exceeding the maximum magnetic permeability is shortened. Focusing on this point, the winding resistance measuring circuits shown in FIGS. 10 and 11 have been devised. In FIG. 10, a variable voltage DC power supply 21 is used, and a high voltage is set when the switch 22 is turned on, and a low voltage is set after a certain period of time. In FIG. 11, a DC power supply 26 of a higher voltage is used, an external resistor 24 is provided in the measurement circuit, and a bypass switch 25 is connected in parallel with the external resistor 24. 25 is opened to obtain a constant saturation current. In either case, as shown in FIG.
A current-time characteristic with a constant saturation current at 1 is obtained.
【０００６】[0006]
【発明が解決しようとする課題】このように可変電圧電
源または外部抵抗の加減により測定電圧を２段階に切り
換えることにより、一定飽和電流に達する時間を短縮で
きるが、例えば変圧器の温度試験時の巻線抵抗測定のよ
うに短時間で測定できなければ測定精度を確保できない
場合には、より一層の迅速化が望まれる。As described above, the time required to reach a constant saturation current can be shortened by switching the measurement voltage in two steps by adjusting the variable voltage power source or the external resistance. For example, in the temperature test of the transformer. In the case where the measurement accuracy cannot be secured unless measurement can be performed in a short time, such as winding resistance measurement, further speedup is desired.
【０００７】そこで本発明は、鉄心を有する巻線の直流
抵抗を自動的に、かつ迅速に測定できる巻線抵抗の測定
方法を提供することを目的とする。Therefore, an object of the present invention is to provide a winding resistance measuring method capable of automatically and quickly measuring the DC resistance of a winding having an iron core.
【０００８】[0008]
【課題を解決するための手段】本発明は、鉄心を有する
巻線に直流電圧を印加し、一定飽和電流として、直流電
圧降下法により巻線の直流抵抗を測定する巻線抵抗測定
方法において、測定回路に検出用抵抗を設け、この検出
用抵抗の電圧降下をディジタル電圧計で測定し、この測
定データなどに基づきＣＰＵで切換時点を求めて、直流
電源が可変電圧電源の場合には電源に、また一定電圧の
直流電源で測定回路に外部抵抗及びそのバイパス用スイ
ッチ回路を有する場合にはバイパス用スイッチ回路に切
換信号を与えることを特徴とする。The present invention provides a winding resistance measuring method in which a DC voltage is applied to a winding having an iron core and the DC resistance of the winding is measured by a DC voltage drop method as a constant saturation current. A detection resistor is provided in the measurement circuit, the voltage drop of this detection resistor is measured with a digital voltmeter, and the CPU determines the switching time point based on this measurement data, etc. In addition, when the measuring circuit has a constant voltage DC power supply and an external resistance and its bypass switch circuit, a switching signal is given to the bypass switch circuit.
【０００９】[0009]
【作用】測定対象の巻線には、初めに高めの電圧が加わ
り、早い時点で電流が急速に上昇する。この電流の変化
を検出用抵抗の電圧降下としてディジタル電圧計で検知
し、このＡ／Ｄ変換データなどに基づきＣＰＵで切換時
点を求めて、可変電圧電源またはバイパス用スイッチ回
路に切換信号を与える。切換信号により電源電圧が低
下、または外部抵抗が増加して巻線の印加電圧が低電圧
となり、測定電流は短時間で一定飽和電流となる。Operation: A high voltage is first applied to the winding to be measured, and the current rapidly rises at an early point. This change in current is detected by the digital voltmeter as a voltage drop in the detection resistor, the CPU determines the switching time point based on the A / D conversion data, and the switching signal is given to the variable voltage power supply or the bypass switch circuit. The switching signal causes the power supply voltage to decrease or the external resistance to increase, so that the voltage applied to the winding becomes a low voltage, and the measured current becomes a constant saturation current in a short time.
【００１０】[0010]
【実施例】以下、本発明を図面に示す実施例に基づいて
説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in the drawings.
【００１１】本発明による巻線抵抗測定方法の実施例１
を図１に示す。図中、１は測定対象の鉄心を有する巻線
（例えば、変圧器巻線）で、直流抵抗１Ｒとインダクタ
ンス１Ｌを持っている。２はけい素鋼板の鉄心などでも
早めに一定飽和電流とすることが可能な電圧を有する可
変電圧直流電源、３は巻線１と電源２の間に設けたスイ
ッチ、４は測定回路に設けた検出用抵抗、５はこの検出
用抵抗４の電圧降下を検出するディジタル電圧計、６は
このディジタル電圧計５の出力（アナログ−ディジタル
変換機能によるＡ／Ｄ変換出力）などに基づいて可変電
圧直流電源２の電圧切換時点を求め、切換信号を電源２
に与えるＣＰＵ（コンピュータ）である。電圧切換時点
は、回路電流が急速に上昇して所要の一定飽和電流に達
した時点（図１２の時点ｔ1）とする。可変電圧直流電
源２は、ＣＰＵ６からの切換信号により高めの初期電圧
から所定の測定電圧に切り換えることができる調整部を
有する構成としている。Embodiment 1 of a winding resistance measuring method according to the present invention
Is shown in FIG. In the figure, 1 is a winding (for example, a transformer winding) having an iron core to be measured, which has a DC resistance 1R and an inductance 1L. 2 is a variable voltage direct current power source having a voltage that can quickly reach a constant saturation current even with an iron core of silicon steel plate, 3 is a switch provided between the winding 1 and the power source 2, and 4 is provided in the measurement circuit. Detecting resistor 5 is a digital voltmeter for detecting the voltage drop of the detecting resistor 4, 6 is a variable voltage direct current based on the output of the digital voltmeter 5 (A / D conversion output by the analog-digital conversion function), etc. The time when the voltage of the power source 2 is switched is obtained, and the switching signal
It is a CPU (computer) given to the. The voltage switching time is the time when the circuit current rapidly rises and reaches the required constant saturation current (time t 1 in FIG. 12). The variable voltage DC power supply 2 is configured to have an adjusting unit that can switch from a higher initial voltage to a predetermined measurement voltage by a switching signal from the CPU 6.
【００１２】巻線１の直流抵抗を測定するには、電源２
の電圧が高めの初期電圧に設定された状態でスイッチ３
を入れる。このスイッチ３の投入で回路電流が流れ始
め、ある時点で急速に上昇する。測定回路に電流が流れ
ると、検出用抵抗４に電圧降下が生じ、これがディジタ
ル電圧計５で測定される。測定データ（アナログ−ディ
ジタル変換機能によるＡ／Ｄ変換出力）は、ＣＰＵ６に
入力され、ここでこの入力などに基づいて電圧切換時点
（電流の急速上昇過程の一時点）が求められる。そし
て、切換信号が電源２に与えられ、電源２の出力電圧が
高めの初期電圧から所定の電圧に切り換えられる。この
後、一定飽和電流となり、巻線１の端子間電圧と電流か
ら巻線１の直流抵抗１Ｒの値が算出される。To measure the DC resistance of the winding 1, the power supply 2
Switch 3 is set to a higher initial voltage
Insert When the switch 3 is turned on, the circuit current starts to flow and rises rapidly at a certain point. When a current flows through the measuring circuit, a voltage drop occurs in the detection resistor 4, which is measured by the digital voltmeter 5. The measurement data (A / D conversion output by the analog-digital conversion function) is input to the CPU 6, and the voltage switching time point (one time point of the rapid increase in current) is obtained based on this input. Then, the switching signal is given to the power supply 2, and the output voltage of the power supply 2 is switched from a higher initial voltage to a predetermined voltage. After that, a constant saturation current is reached, and the value of the DC resistance 1R of the winding 1 is calculated from the voltage and current between the terminals of the winding 1.
【００１３】実施例２を図２に示す。実施例２では、け
い素鋼板の鉄心などでも早めに一定飽和電流とすること
が可能な電圧の直流電源７を用い、測定回路に外部抵抗
８とそのバイパス用スイッチ回路９を設けている。バイ
パス用スイツチ回路９は、ＣＰＵ６からの切換信号によ
りそのオン，オフを制御できる構成としている。Example 2 is shown in FIG. In the second embodiment, a DC power supply 7 having a voltage that can quickly bring a constant saturation current to an iron core of a silicon steel plate is used, and an external resistor 8 and its bypass switch circuit 9 are provided in the measurement circuit. The bypass switch circuit 9 can be turned on and off by a switching signal from the CPU 6.
【００１４】巻線１の抵抗測定は、スイツチ回路９がオ
ンしている状態で開始する。スイッチ３を入れると、外
部抵抗８が短絡されているため、実施例１と同様の動作
となり、ある時点でＣＰＵ６から切換信号が出る。この
切換信号によりスイッチ回路９がオフとなり、測定回路
に外部抵抗８が挿入される。この外部抵抗８に電圧降下
が生じ、巻線１の端子間電圧が低下する。この後、一定
飽和電流となり、巻線１の端子間電圧と電流から巻線１
の直流抵抗１Ｒの値が算出される。The measurement of the resistance of the winding 1 starts with the switch circuit 9 turned on. When the switch 3 is turned on, since the external resistor 8 is short-circuited, the operation is the same as that of the first embodiment, and the CPU 6 outputs a switching signal at a certain point. This switching signal turns off the switch circuit 9 and inserts the external resistor 8 into the measurement circuit. A voltage drop occurs in the external resistor 8 and the voltage across the terminals of the winding 1 drops. After that, a constant saturation current is reached, and from the terminal voltage and current of winding 1, winding 1
The value of the DC resistance 1R of is calculated.
【００１５】このように電圧切換を自動化することによ
り、実施例１，２のいずれの場合にも一定飽和電流を短
時間で得られるようになり、測定の迅速化が図れる。By automating the voltage switching as described above, a constant saturation current can be obtained in a short time in any of the first and second embodiments, and the measurement can be speeded up.
【００１６】[0016]
【発明の効果】以上のように本発明によれば、測定回路
の検出用抵抗の電圧降下をディジタル電圧計で測定し、
この測定データなどに基づきＣＰＵで切換時点を求め
て、可変電圧電源またはバイパス用スイッチ回路に切換
信号を与えることにより、変圧器巻線などのように鉄心
を有する、時定数の大きな巻線でも、速やかに一定飽和
電流とすることができるようになり、短時間で直流抵抗
の測定が可能となって、温度試験時の巻線温度推定では
高精度が期待できる。As described above, according to the present invention, the voltage drop of the detecting resistor of the measuring circuit is measured by the digital voltmeter,
Even if the winding has a large time constant, such as a transformer winding, which has an iron core, the switching time is calculated by the CPU based on this measurement data and the switching signal is given to the variable voltage power supply or the bypass switch circuit. The constant saturation current can be quickly achieved, and the direct current resistance can be measured in a short time, and high accuracy can be expected in estimating the winding temperature during the temperature test.
【図１】本発明による巻線抵抗の測定方法の実施例１を
示す回路図。FIG. 1 is a circuit diagram showing a first embodiment of a winding resistance measuring method according to the present invention.
【図２】本発明による巻線抵抗の測定方法の実施例２を
示す回路図。FIG. 2 is a circuit diagram showing a second embodiment of a winding resistance measuring method according to the present invention.
【図３】変圧器の巻線抵抗を測定する回路を示す回路
図。FIG. 3 is a circuit diagram showing a circuit for measuring winding resistance of a transformer.
【図４】変圧器巻線抵抗の測定回路の等価回路を示す回
路図。FIG. 4 is a circuit diagram showing an equivalent circuit of a transformer winding resistance measuring circuit.
【図５】測定電流の変化状態を示す電流−時間特性図。FIG. 5 is a current-time characteristic diagram showing the change state of the measured current.
【図６】変圧器の鉄心に使用されるけい素鋼板の磁気特
性を示す透磁率特性図。FIG. 6 is a magnetic permeability characteristic diagram showing magnetic characteristics of a silicon steel sheet used for an iron core of a transformer.
【図７】鉄心にけい素鋼板を用いた時の電流変化状態を
示す電流−時間特性図。FIG. 7 is a current-time characteristic diagram showing a current change state when a silicon steel plate is used for the iron core.
【図８】鉄心を有する巻線の抵抗を測定する回路を示す
回路図。FIG. 8 is a circuit diagram showing a circuit for measuring the resistance of a winding having an iron core.
【図９】異なる印加電圧値での特性を示す電流−時間特
性図。FIG. 9 is a current-time characteristic diagram showing characteristics at different applied voltage values.
【図１０】可変電圧電源を用いた測定回路を示す回路
図。FIG. 10 is a circuit diagram showing a measurement circuit using a variable voltage power supply.
【図１１】外部抵抗及びそのバイパス用スイッチ回路を
設けた測定回路を示す回路図。FIG. 11 is a circuit diagram showing a measuring circuit provided with an external resistor and a switch circuit for bypassing the external resistor.
【図１２】巻線の印加電圧を切り換えた場合の電流変化
状態を示す電流−時間特性図。FIG. 12 is a current-time characteristic diagram showing a current change state when the voltage applied to the winding is switched.
１…鉄心を有する巻線 １Ｒ…直流抵抗 １Ｌ…インダクタンス ２…可変電圧直流電源 ３…スイッチ ４…検出用抵抗 ５…ディジタル電圧計 ６…ＣＰＵ ７…直流電源 ８外部抵抗 ９…バイパス用スイッチ回路 1 ... Winding having an iron core 1R ... DC resistance 1L ... Inductance 2 ... Variable voltage DC power supply 3 ... Switch 4 ... Detection resistance 5 ... Digital voltmeter 6 ... CPU 7 ... DC power supply 8 External resistance 9 ... Bypass switch circuit
Claims (1)
一定飽和電流として、直流電圧降下法により巻線の直流
抵抗を測定する巻線抵抗の測定方法において、測定回路
に検出用抵抗を設け、この検出用抵抗の電圧降下をディ
ジタル電圧計で測定し、この測定データなどに基づきＣ
ＰＵで切換時点を求めて、直流電源が可変電圧電源の場
合には電源に、また一定電圧の直流電源で測定回路に外
部抵抗及びそのバイパス用スイッチ回路を有する場合に
はバイパス用スイッチ回路に切換信号を与えることを特
徴とする巻線抵抗の測定方法。1. A DC voltage is applied to a winding having an iron core,
As a constant saturation current, in the winding resistance measuring method that measures the DC resistance of the winding by the DC voltage drop method, a detection resistance is provided in the measurement circuit, and the voltage drop of this detection resistance is measured with a digital voltmeter. C based on this measurement data
Determine the switching time point at the PU and switch to the power supply if the DC power supply is a variable voltage power supply, or to the bypass switch circuit if the measurement circuit has a constant voltage DC power supply and the external resistance and its bypass switch circuit. A method for measuring winding resistance, characterized by applying a signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7149804A JPH095368A (en) | 1995-06-16 | 1995-06-16 | Method for measuring resistance of wiring |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7149804A JPH095368A (en) | 1995-06-16 | 1995-06-16 | Method for measuring resistance of wiring |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH095368A true JPH095368A (en) | 1997-01-10 |
Family
ID=15483083
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7149804A Pending JPH095368A (en) | 1995-06-16 | 1995-06-16 | Method for measuring resistance of wiring |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH095368A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011229226A (en) * | 2010-04-16 | 2011-11-10 | Mitsubishi Electric Corp | Eccentricity estimation method of rotating electric machine and eccentricity estimation system of rotating electric machine |
| EP3185024A1 (en) * | 2015-12-23 | 2017-06-28 | Schneider Electric USA, Inc. | Current transformer with enhanced temperature measurement functions |
| CN110850171A (en) * | 2019-11-29 | 2020-02-28 | 国网山东省电力公司青岛供电公司 | A method for evaluating the qualification of DC resistance of voltage regulating transformers |
| CN112213650A (en) * | 2019-07-11 | 2021-01-12 | 丰田自动车株式会社 | Method for inspecting electric storage device and method for manufacturing electric storage device |
-
1995
- 1995-06-16 JP JP7149804A patent/JPH095368A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011229226A (en) * | 2010-04-16 | 2011-11-10 | Mitsubishi Electric Corp | Eccentricity estimation method of rotating electric machine and eccentricity estimation system of rotating electric machine |
| EP3185024A1 (en) * | 2015-12-23 | 2017-06-28 | Schneider Electric USA, Inc. | Current transformer with enhanced temperature measurement functions |
| CN106908656A (en) * | 2015-12-23 | 2017-06-30 | 施耐德电气美国股份有限公司 | Current transformer with enhanced temperature measurement function |
| US10132697B2 (en) | 2015-12-23 | 2018-11-20 | Schneider Electric USA, Inc. | Current transformer with enhanced temperature measurement functions |
| CN106908656B (en) * | 2015-12-23 | 2021-05-28 | 施耐德电气美国股份有限公司 | Current transformer with enhanced temperature measurement |
| CN112213650A (en) * | 2019-07-11 | 2021-01-12 | 丰田自动车株式会社 | Method for inspecting electric storage device and method for manufacturing electric storage device |
| CN112213650B (en) * | 2019-07-11 | 2024-04-23 | 丰田自动车株式会社 | Inspection method and manufacturing method for power storage device |
| CN110850171A (en) * | 2019-11-29 | 2020-02-28 | 国网山东省电力公司青岛供电公司 | A method for evaluating the qualification of DC resistance of voltage regulating transformers |
| CN110850171B (en) * | 2019-11-29 | 2021-09-17 | 国网山东省电力公司青岛供电公司 | Evaluation method for DC resistance qualification degree of voltage regulating transformer |
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