JPH0684672A - Ammeter for bus - Google Patents
Ammeter for busInfo
- Publication number
- JPH0684672A JPH0684672A JP4233454A JP23345492A JPH0684672A JP H0684672 A JPH0684672 A JP H0684672A JP 4233454 A JP4233454 A JP 4233454A JP 23345492 A JP23345492 A JP 23345492A JP H0684672 A JPH0684672 A JP H0684672A
- Authority
- JP
- Japan
- Prior art keywords
- coil
- coils
- current
- bus
- bus bar
- 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.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F38/00—Adaptations of transformers or inductances for specific applications or functions
- H01F38/20—Instruments transformers
- H01F38/22—Instruments transformers for single phase ac
- H01F38/28—Current transformers
- H01F38/30—Constructions
- H01F2038/305—Constructions with toroidal magnetic core
Landscapes
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Transformers For Measuring Instruments (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】母線の電流値の監視を複数の場所
で行なう場合、又はある区間の両端に電流測定器を設
け、電流検出の差動をとってその区間の地絡検出を行な
う場合等には母線における同じ位置での電流測定を複数
の電流測定器で行う必要が生じることがある。本発明は
このような場合において、母線における同じ位置でその
母線に流れる電流によって複数の電流測定用検出コイル
のそれぞれに誘起電圧を生じさせ、それにより複数の測
定出力を得る母線の電流測定器に関するものである。[Industrial application] When monitoring the current value of a bus bar at multiple locations, or when a current measuring device is installed at both ends of a section and current detection is performed differentially to detect the ground fault in that section. In some cases, it may be necessary to perform current measurement at the same position on the bus bar using a plurality of current measuring devices. In such a case, the present invention relates to a bus bar current measuring device for producing a plurality of measurement outputs by generating an induced voltage in each of a plurality of current measuring detection coils by a current flowing through the bus bar at the same position in the bus bar. It is a thing.
【０００２】[0002]
【従来の技術】図５は母線における同じ位置で複数の電
流測定用検出装置により母線に流れる電流を検出する従
来の母線の電流測定器を示す。被測定電流が流れている
母線１の周囲には絶縁物からなる円環形状の巻心12aが
母線１をその中心におくように配設され、巻心12aに実
質的に等巻線密度で巻回したコイル13aの両端の間には
負荷15aが電気的に接続される。そしてコイル13aの外周
には絶縁物14aが配設されている。被測定電流が流れて
いる母線１の周囲にはさらに絶縁物からなる他の円環形
状の巻心12bが前記の巻心12aに隣接し且つ母線１をその
中心におくように配設されている。巻心12bに実質的に
等巻線密度で巻回したコイル13bの両端の間にはもう一
つの負荷15bが電気的に接続される。そしてコイル13bの
外周には絶縁物14bが配設されている。2. Description of the Related Art FIG. 5 shows a conventional bus bar current measuring device which detects a current flowing through the bus bar by a plurality of current measuring detectors at the same position on the bus bar. A ring-shaped core 12a made of an insulating material is arranged around the busbar 1 through which the measured current flows so that the busbar 1 is placed at the center of the busbar 1 and the core 12a has substantially the same winding density. A load 15a is electrically connected between both ends of the wound coil 13a. An insulator 14a is arranged on the outer circumference of the coil 13a. Around the busbar 1 through which the current to be measured flows, another ring-shaped winding core 12b made of an insulating material is arranged adjacent to the winding core 12a and with the busbar 1 at the center. There is. Another load 15b is electrically connected between both ends of the coil 13b wound around the winding core 12b with substantially equal winding density. An insulator 14b is arranged on the outer circumference of the coil 13b.
【０００３】次に図５に示した従来技術の動作について
説明する。母線１に流れる電流Ｉによってコイル13a,13
b内には磁界Ｈが発生する。この電流Ｉと磁界Ｈおよび
磁束密度Ｂとの関係は次式のとおりである。 Ｉ＝∫H・dl＝∫(B/μ0)・dl (1') 母線に流れる電流Ｉを角周波数ωの正弦波交流とし、コ
イル13aの母線周方向微小長さをΔl'、その間の巻数を
N'、コイル13aの磁界Ｈと鎖交する鎖交断面積をSa'、コ
イル13aを鎖交する磁束をΦa'、誘起電圧をｅ'とすると
上記(1)式より Ｉ＝Σ｛Φa'・Δl'/(μ0・Sa')｝ (2') ｜Ｉ｜＝Δl'・Σ｛e/(N'・μ0・Sa'・ω)｝ (3') が得られる。N'/Δl'はコイル13aの周方向巻線密度na'
であり、コイル13aは等巻線密度で巻心12aに巻回されて
いるのでna'は一定であり、鎖交断面積Sa'も周方向で一
定とすると、母線１に流れる電流Ｉによるコイル13aの
誘起電圧Ea'との関係は次式になる。 ｜Ｉ｜＝Ea'/(na'・μ0・Sa'・ω) (4') したがってコイル13aの誘起電圧Ea'により、母線１に流
れる電流Ｉを測定することができる。同様にしてコイル
13bの誘起電圧Eb'と母線１に流れる電流Ｉの関係は次式
のとおりになる。 ｜Ｉ｜＝Eb'/(nb'・μ0・Sb'・ω) (5') したがってコイル13bの誘起電圧Eb'により同じ母線位置
で母線１に流れる電流Ｉを測定することができる。Next, the operation of the prior art shown in FIG. 5 will be described. The current I flowing through the bus bar 1 causes the coils 13a, 13
A magnetic field H is generated in b. The relationship between the current I, the magnetic field H, and the magnetic flux density B is as follows. I = ∫H ・ dl = ∫ (B / μ 0 ) ・ dl (1 ') The current I flowing in the bus is a sinusoidal alternating current of angular frequency ω, and the minute length of the coil 13a in the circumferential direction of the bus is Δl'. Number of turns
Let N ′ be the cross-sectional area of the coil 13a that interlinks with the magnetic field H, Sa ′, the magnetic flux that links the coil 13a be Φa ′, and the induced voltage be e ′, then I = Σ {Φa ′ from the above equation (1). · Δl '/ (μ 0 · Sa')} (2 ') | I | = Δl' · Σ {e / (N '· μ 0 · Sa' · ω)} (3 ') is obtained. N '/ Δl' is the circumferential winding density na 'of coil 13a
Since the coil 13a is wound around the core 12a with an equal winding density, na 'is constant, and if the interlinkage cross-sectional area Sa' is also constant in the circumferential direction, the coil due to the current I flowing in the busbar 1 is The relationship between the induced voltage Ea 'of 13a is as follows. | I | = by Ea '/ (na' · μ 0 · Sa '· ω) (4') thus induced voltage Ea of the coil 13a ', it is possible to measure the current I flowing through the bus 1. Coil in the same way
The relationship between the induced voltage Eb ′ of 13b and the current I flowing through the bus 1 is as follows. | I | = Eb ′ / (nb ′ · μ 0 · Sb ′ · ω) (5 ′) Therefore, the induced voltage Eb ′ of the coil 13b can measure the current I flowing through the bus 1 at the same bus bar position.
【０００４】[0004]
【発明が解決しようとする課題】母線における同じ位置
で複数の電流測定用検出装置により母線１に流れる電流
を検出する従来の母線の電流測定器は以上のように構成
されていたので、母線１に流れる電流Ｉによって発生す
る磁束を鎖交する面積を別々に設ける必要があり、その
ため電流測定器が大型となる問題があった。この発明は
母線における同じ位置で複数の電流測定用検出用コイル
により母線に流れる電流を検出することにより母線の電
流測定器を小型化することを目的とする。The conventional bus bar current measuring device for detecting the current flowing through the bus bar 1 by a plurality of current measuring detectors at the same position on the bus bar has been constructed as described above. It is necessary to separately provide areas for interlinking the magnetic flux generated by the current I flowing through the current measuring device, which causes a problem that the current measuring device becomes large. An object of the present invention is to downsize a bus current measuring device by detecting a current flowing through the bus with a plurality of current measuring detection coils at the same position on the bus.
【０００５】[0005]
【課題を解決するための手段】請求項１の母線の電流測
定器は被測定電流が流れている母線の周囲に前記母線を
中心として配設された絶縁物からなり実質的に円環形状
の巻心と、前記巻心全周に実質的に等巻線密度で巻回し
た第１のコイルと、前記第１のコイルの両端の間に電気
的に接続された第１の負荷と、前記第１のコイルの外周
に巻枠全周に実質的に等巻線密度で巻回した少なくとも
１つのコイルと、前記少なくとも１つのコイルの各両端
の間に電気的にそれぞれ接続された各負荷とを有し前記
第１のコイル及び少なくとも１つのコイルのそれぞれに
接続された前記各負荷を含むインピーダンスZLの値は ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ) 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧(V)，Ｉ：被測定電流(A) に設定されていることを特徴とする。請求項２の母線の
電流測定器は被測定電流が流れている母線の周囲に前記
母線を中心として配設された絶縁物からなり実質的に円
環形状の巻心と、前記巻心上に同層で順次に巻回した複
数のコイルと、前記複数のコイルの各両端の間に電気的
にそれぞれ接続された各負荷とを有し、前記複数のコイ
ルの各両端の間に電気的にそれぞれ接続された前記各負
荷を含むインピーダンスZLの値は ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ) 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧(V)，Ｉ：被測定電流(A) に設定されていることを特徴とする。請求項３の母線の
電流測定器は、被測定電流が流れている母線の周囲に前
記母線を中心として配設された絶縁物からなり実質的に
円環形状の巻心と、前記巻心の母線円周方向に順番に巻
回したコイルを１つのオープンループを形成して少なく
とも１つおきに直列に接続された複数のコイルと、前記
複数のコイルの外周に前記母線を中心として配設された
導電材料のタンクと、前記複数のコイルの各両端の間に
電気的にそれぞれ接続された各負荷とを有し前記複数の
コイルの各両端の間に電気的にそれぞれ接続された各負
荷を含むインピーダンスZLの値は ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ) 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧(V)，Ｉ：被測定電流(A) に設定されていることを特徴とする。According to a first aspect of the present invention, there is provided an electric current measuring device for a bus bar, which is made of an insulator arranged around the bus bar in which a current to be measured flows and which has a substantially annular shape. A core, a first coil wound around the entire circumference of the core at substantially equal winding density, a first load electrically connected between both ends of the first coil, and At least one coil wound around the entire circumference of the first coil at substantially the same winding density on the outer periphery of the first coil, and loads electrically connected between both ends of the at least one coil, respectively. The value of the impedance Z L including each load connected to each of the first coil and at least one coil is Z L > N · E · (M−1) / (5 × 10 −3 · I) However, M: number of coils, N: number of turns of each coil, E: coil induced voltage (V), I: current to be measured (A) And said that you are. 3. The busbar current measuring device according to claim 2, wherein the busbar has a substantially annular winding core and is made of an insulating material and is arranged around the busbar around which the current to be measured flows. A plurality of coils sequentially wound in the same layer, and a load electrically connected between both ends of the plurality of coils, respectively, and electrically between the ends of the plurality of coils. The value of the impedance Z L including the respective loads connected to each other is Z L > N · E · (M-1) / (5 × 10 −3 · I) where M is the number of coils, N is the number of turns of each coil, It is characterized in that E: coil induced voltage (V) and I: measured current (A) are set. The busbar current measuring device according to claim 3 comprises a substantially annular winding core made of an insulator disposed around the busbar around which the current to be measured flows, and the core. A plurality of coils, in which at least every other coil is wound in order in the circumferential direction of the bus bar to form an open loop, and are connected in series, and the coils are arranged around the bus bar on the outer circumference of the plurality of coils. A conductive material tank and loads respectively electrically connected between both ends of the plurality of coils, and loads electrically connected respectively between both ends of the plurality of coils. The value of impedance Z L is Z L > N ・ E ・ (M-1) / (5 × 10 -3・ I) where M: number of coils, N: number of turns of each coil, E: coil induced voltage (V) , I: The measured current (A) is set.
【０００６】[0006]
【作用】複数のコイルは母線の周囲に配設された絶縁物
からなる実質的に円環形状の共通の巻心に巻回される。
複数のコイルに接続された負荷を含むインピーダンスZL
の値を ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ） 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧（Ｖ），Ｉ：被測定電流(A) と設定して複数のコイルに流れる電流を制限することに
より測定精度の低下を防ぐ。The plurality of coils are wound on a common substantially circular ring-shaped core made of an insulating material and arranged around the bus bar.
Impedance Z L including loads connected to multiple coils
The value of Z L ＞ N ・ E ・ (M-1) / (5 × 10 -3・ I) where M: number of coils, N: number of turns of each coil, E: coil induced voltage (V), I: target Setting the measurement current (A) to limit the current flowing through multiple coils prevents the measurement accuracy from decreasing.
【０００７】[0007]
【実施例】図１はこの発明による母線の電流測定器の一
実施例を示す。被測定電流が流れている母線１の周囲に
は例えば合成樹脂等の絶縁物からなり実質的に円環形状
の巻心２が母線１を中心とおくように配設されている。
巻心２には実質的に等巻線密度でコイル3aが巻回される
と共にコイル3aの外周には絶縁物4aが配設されている。
絶縁物4aには等巻線密度でコイル3bが巻回されると共に
コイル3bの外周には絶縁物4bが配設されている。第一の
負荷5aはコイル3aの両端の間に電気的に接続され、第二
の負荷5bはコイル3bの両端の間に電気的に接続される。
なおコイル3aの外周に巻枠全周に実質的に等巻線密度で
巻回したコイル3bが１個の実施例を図１において例示し
たがコイル3aの外周に１個以上の複数のコイルを巻枠全
周に実質的に等巻線密度で巻回し、前記１個以上の複数
のコイルの両端にそれぞれ負荷を電気的に接続してそれ
ぞれの負荷により母線に流れる電流を検出する実施例も
可能である。1 shows an embodiment of a bus current measuring device according to the present invention. Around the busbar 1 through which the current to be measured flows, a substantially annular winding core 2 made of an insulating material such as synthetic resin is arranged with the busbar 1 as the center.
A coil 3a is wound around the winding core 2 at a substantially equal winding density, and an insulator 4a is arranged on the outer circumference of the coil 3a.
A coil 3b is wound around the insulator 4a with a uniform winding density, and the insulator 4b is arranged on the outer periphery of the coil 3b. The first load 5a is electrically connected between both ends of the coil 3a, and the second load 5b is electrically connected between both ends of the coil 3b.
It should be noted that the embodiment in which one coil 3b is wound around the outer circumference of the coil 3a at substantially the same winding density all around the winding frame is shown in FIG. 1, but one or more coils are wound around the outer circumference of the coil 3a. There is also an embodiment in which winding is wound around the entire circumference of the winding frame with substantially equal winding density, and a load is electrically connected to both ends of the one or more coils to detect a current flowing in the busbar by each load. It is possible.
【０００８】次に図１に示した実施例の動作について説
明する。母線１に流れる電流Ｉによってコイル3a,3b内
には磁界Ｈが発生する。この電流Ｉと磁界Ｈおよび磁束
密度Ｂとの関係は、電流のまわりの任意の閉曲線上の長
さをl、真空の透磁率をμ0とすると、次式のとおりであ
る。 Ｉ＝∫H・dl＝∫(B/μ0)・dl (1) 母線１に流れる電流Ｉを角周波数ωの正弦波交流とし、
コイル3aの母線周方向微小長さをΔl、その間の巻数を
Ｎ、コイル3aの磁界Ｈと鎖交する鎖交断面積をSa、コイ
ル3aに鎖交する磁束をΦa、誘起電圧をｅとすると、上
記(1)式より、 Ｉ＝Σ｛Φa・Δl/(μ0・Sa)｝ （２） ｜Ｉ｜＝Δｌ・Σ｛e/(Ｎ・μ0・Sa・ω)｝ (3) が得られる。N/Δlはコイル3aの周方向巻線密度naであ
り、コイル3aは等巻線密度で巻心2に巻回されているの
でnaは一定であり、鎖交断面積Saも周方向で一定とする
と母線１に流れる電圧Ｉによるコイル3aの誘起電圧Eaと
の関係は次式になる。 ｜Ｉ｜＝Ea/(na・μ0・Sa・ω) (4) したがってコイル3aの誘起電圧Eaにより、母線１に流れ
る電流Ｉを測定することができる。同様にして、コイル
3bの誘起電圧Ebにより母線１に流れる電流Ｉを測定する
ことができる。しかしながらコイル3aには母線１に流れ
る電流Ｉにより発生する磁束の他にコイル3bに流れる二
次電流により発生する磁束も重畳した磁束Φbが鎖交す
る。このため負荷5a、5bの大きさを所定の値以上のもの
に限定しなければ電流値の測定精度が悪くなる。電流Ｉ
によりコイル3aに発生する磁束Φiは Φi＝２×１０-7・Ｉ・Sa/r (5) である。ただしｒは巻心２の半径である。一方コイル3b
に流れる二次電流ibによってコイル3aに発生する磁束Φ
bは Φb＝２×１０-7・Nb・ib・Sa/r (6) である。ここでNbはコイル3bの巻数である。コイル3aの
誘起電圧はこれらの磁束の重畳した磁束により求まる。
等巻線密度および等鎖交断面積には製作できないという
製作誤差も含めて電流値の測定精度を１％以内にしよう
とすると、コイル3bに流れる二次電流ibによってコイル
3aに発生する磁束Φbの大きさは測定精度0.5％以下であ
るとよい。 Φb＜0.005×Φi (7) 上式に(5)(6)式を代入すると測定精度に影響を与える二
次電流ibは ib＜0.005×Ｉ/Nb (8) となる。電流測定器は誘起電圧から換算して電流値を測
定するものであることから負荷5a、5bは例えば電圧計な
どの高インピーダンス機器である。このためコイル3bの
巻線抵抗などを省くと負荷5bのインピーダンスZbは Zb＝Eb/ib (9) となる。上式を(8)式に代入すると Zb＞Nb・Eb/(0.005×Ｉ) (10) となる。電流Ｉによってコイル3a、3bに誘起する電圧E
a、Ebが同じ電圧になるようにすると (Na・Sa=Nb・Sb)、
ZaはZbと同じ値となる。なおコイル数がＭ個の複数コイ
ルの場合、コイルに流れる二次電流による磁束がコイル
数分だけ増加するため各コイルにつながるインピーダン
スＺLは ＺL＞N・E・(M-1)/(0.005×Ｉ) (11) となる。ただしＭは２以上である。(11)式より、母線１
の周囲に配設された円環形状の巻心２に巻回される複数
のコイルにそれぞれ接続された負荷を含むインピーダン
スZLの値を ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ) (12) 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧(V)，Ｉ：被測定電流(A) と設定すれば所定の測定精度が得られる。なお、コイル
の巻線が細く巻数が多い場合、巻線抵抗が大きくなる。
この場合は負荷のインピーダンスは上式の値から、巻線
抵抗が大きくなった分を差し引いた値となる。図１の実
施例ではコイル3aとコイル3bとは層をわけて設けている
が、図４に示すようにコイルの巻数が少ない場合では母
線１の円周方向にコイル3aの巻線と少なくとも１つのコ
イル3bの巻線を交互に、すなわち、コイル3aの１ターン
の次に少なくとも１つのコイル3bを１ターン巻き、これ
を繰り返して順次巻回するようにして２個以上の複数の
コイルを同層に巻回することもできる。Next, the operation of the embodiment shown in FIG. 1 will be described. A magnetic field H is generated in the coils 3a and 3b by the current I flowing through the bus 1. The relationship between the current I, the magnetic field H, and the magnetic flux density B is given by the following equation, where l is the length on an arbitrary closed curve around the current and μ 0 is the magnetic permeability of the vacuum. I = ∫H ・ dl = ∫ (B / μ 0 ) ・ dl (1) The current I flowing in the bus bar 1 is a sine wave alternating current of angular frequency ω,
Let Δl be the minute length of the coil 3a in the circumferential direction of the generatrix, N be the number of turns between them, Sa be the interlinking cross-sectional area interlinking with the magnetic field H of the coil 3a, Φa be the magnetic flux interlinking with the coil 3a, and e be the induced voltage. From the above formula (1), I = Σ {Φa · Δl / (μ 0 · Sa)} (2) | I | = Δl · Σ {e / (N · μ 0 · Sa · ω)} (3) Is obtained. N / Δl is the winding density na in the circumferential direction of the coil 3a, and since the coil 3a is wound around the winding core 2 with an equal winding density, na is constant and the cross-sectional area Sa is also constant in the circumferential direction. Then, the relationship with the induced voltage Ea of the coil 3a due to the voltage I flowing through the bus bar 1 is as follows. | I | = Ea / (na · μ 0 · Sa · ω) (4) Therefore, the current I flowing in the bus bar 1 can be measured by the induced voltage Ea of the coil 3a. Similarly, the coil
The current I flowing in the bus bar 1 can be measured by the induced voltage Eb of 3b. However, in the coil 3a, in addition to the magnetic flux generated by the current I flowing in the bus bar 1, the magnetic flux Φb in which the magnetic flux generated by the secondary current flowing in the coil 3b is superimposed is linked. Therefore, unless the sizes of the loads 5a and 5b are limited to a predetermined value or more, the current value measurement accuracy deteriorates. Current I
Thus, the magnetic flux Φi generated in the coil 3a is Φi = 2 × 10 −7 · I · Sa / r (5). However, r is the radius of the winding core 2. Meanwhile coil 3b
Magnetic flux Φ generated in the coil 3a by the secondary current ib flowing in
b is Φb = 2 × 10 −7 · Nb · ib · Sa / r (6). Here, Nb is the number of turns of the coil 3b. The induced voltage of the coil 3a is obtained by the magnetic flux in which these magnetic fluxes are superposed.
If you try to make the measurement accuracy of the current value within 1%, including the manufacturing error that it cannot be manufactured in the equal winding density and the equal cross-section area, the secondary current ib flowing in the coil 3b causes the coil
The magnitude of the magnetic flux Φb generated in 3a is preferably 0.5% or less in measurement accuracy. Φb <0.005 × Φi (7) Substituting Eqs. (5) and (6) into the above formula, the secondary current ib that affects the measurement accuracy is ib <0.005 × I / Nb (8). Since the current measuring device measures the current value by converting the induced voltage, the loads 5a and 5b are high impedance devices such as a voltmeter. Therefore, if the winding resistance of the coil 3b is omitted, the impedance Zb of the load 5b becomes Zb = Eb / ib (9). Substituting the above equation into equation (8), Zb> Nb · Eb / (0.005 × I) (10). Voltage E induced in coils 3a and 3b by current I
When a and Eb are set to the same voltage (Na ・ Sa = Nb ・ Sb),
Za has the same value as Zb. When the number of coils is M, the magnetic flux due to the secondary current flowing through the coils increases by the number of coils, so the impedance Z L connected to each coil is Z L > N ・ E ・ (M-1) / ( It becomes 0.005 × I) (11). However, M is 2 or more. From equation (11), bus 1
The value of the impedance Z L including the loads respectively connected to the plurality of coils wound around the ring-shaped winding core 2 arranged around Z L is Z L > N · E · (M-1) / ( 5 × 10 -3 · I) (12) However, if you set M: number of coils, N: number of turns of each coil, E: coil induced voltage (V), I: current to be measured (A), the specified measurement accuracy will be obtained. can get. When the coil winding is thin and the number of windings is large, the winding resistance increases.
In this case, the impedance of the load is the value obtained by subtracting the increased winding resistance from the value in the above equation. In the embodiment of FIG. 1, the coil 3a and the coil 3b are provided in different layers, but when the number of turns of the coil is small as shown in FIG. The windings of the three coils 3b are alternately arranged, that is, one turn of the coil 3a is followed by one turn of at least one coil 3b, and this winding is repeated to sequentially wind two or more coils. It can also be wound in layers.
【０００９】図２はこの発明による母線の電流測定器の
他の実施例を示す。図２の実施例は製造過程に於いて巻
心２にコイル3a'を巻き、コイル3a'による誘起電圧の精
度を測定した後、巻心２とコイル3a'を箱６に挿入す
る。そして箱６を巻粋としてコイル3b'を巻いている。
コイル3a'は内側に設けているため誘起電圧の調整はコ
イル3b'を巻く前に行う。コイル3b'は箱６を巻粋として
巻いているため、コイル3b'を巻くときにコイル3a'に力
を加えずに済み、図１の実施例に比較してコイル3a'の
巻線は移動しないので、誘起電圧の変動が図１の実施例
に比較して少なくすることができる。FIG. 2 shows another embodiment of the bus current measuring device according to the present invention. In the embodiment shown in FIG. 2, the coil 3a 'is wound around the core 2 in the manufacturing process, the accuracy of the induced voltage by the coil 3a' is measured, and then the core 2 and the coil 3a 'are inserted into the box 6. Then, the coil 6b 'is wound with the box 6 as a roll.
Since the coil 3a 'is provided inside, adjustment of the induced voltage is performed before winding the coil 3b'. Since the coil 3b 'is formed by winding the box 6 as a winding, it is not necessary to apply a force to the coil 3a' when winding the coil 3b ', and the winding of the coil 3a' is moved as compared with the embodiment of FIG. Therefore, the variation of the induced voltage can be reduced as compared with the embodiment of FIG.
【００１０】図３はこの発明による母線の電流測定器の
さらに他の実施例を示す。被測定電流が流れている母線
１の周囲には絶縁物からなる円環形状の巻心２が母線１
を中心とおくように配設されている。巻心２にはコイル
3a"とコイル3b"とが母線１の円周方向に順番に配設さ
れ、コイル3a"同志及びコイル3b"同志はそれぞれ１つの
オープンループを形成するように１つおきに直列に接続
されている。コイル3a"、3b"の外周には導電材料である
タンク７が配設されている。一般に、このようにコイル
3a"及び3b"を順番に配設した場合には等巻線密度となら
ないので、他の母線が近接しているとコイル3a"及び3b"
からの出力の誤差が大きくなる。しかし、本実施例の構
成においては、外部の他の母線からの磁束がタンク７に
より遮蔽されるのでコイル3a"、3b"と鎖交する磁束は母
線１に流れる電流Ｉにより発生する磁束のみとなる。し
たがってコイル3a"、3b"を母線１の円周方向に順番に設
けても精度良く測定できる。FIG. 3 shows still another embodiment of the bus current measuring device according to the present invention. A ring-shaped core 2 made of an insulating material is provided around the busbar 1 through which the current to be measured flows.
Is arranged so as to be centered. A coil is attached to the core 2.
3a "and coils 3b" are arranged in sequence in the circumferential direction of the bus bar 1, and the coils 3a "comrades and the coils 3b" comrades are connected in series so that every other one forms an open loop. There is. A tank 7 made of a conductive material is arranged around the coils 3a "and 3b". In general, coils like this
If 3a "and 3b" are arranged in order, the winding density will not be equal, so if other busbars are close to each other, coils 3a "and 3b"
The error of the output from becomes large. However, in the configuration of the present embodiment, since the magnetic flux from another external bus bar is shielded by the tank 7, the magnetic flux interlinking with the coils 3a "and 3b" is only the magnetic flux generated by the current I flowing through the bus bar 1. Become. Therefore, even if the coils 3a "and 3b" are sequentially provided in the circumferential direction of the bus bar 1, accurate measurement can be performed.
【００１１】[0011]
【発明の効果】この発明では、母線１の周囲に配設され
た円環形状の共通の巻心２に複数のコイルを巻回してこ
の複数のコイルのそれぞれに誘起電圧を生じさせ、それ
により複数の測定出力を得ると共にコイルに接続された
外部インピーダンスZLが所定値より大きくなるように負
荷を制限したので、母線１に流れる電流と複数のコイル
に流れる電流の磁束の重畳による測定精度の低下という
問題を克服しつつ、電流測定器を小型化することができ
る。According to the present invention, a plurality of coils are wound around a common annular core 2 arranged around the bus bar 1 to generate an induced voltage in each of the plurality of coils, whereby Since the load is limited so that multiple measurement outputs are obtained and the external impedance Z L connected to the coil is larger than a predetermined value, the measurement accuracy due to the superposition of the current flowing through the bus 1 and the magnetic flux of the current flowing through the multiple coils is improved. The current measuring device can be downsized while overcoming the problem of deterioration.
【図１】この発明による母線の電流測定器の一実施例の
断面図FIG. 1 is a sectional view of an embodiment of a busbar current measuring device according to the present invention.
【図２】この発明による母線の電流測定器の他の実施例
の断面図FIG. 2 is a sectional view of another embodiment of the busbar current measuring device according to the present invention.
【図３】この発明による母線の電流測定器のさらに他の
実施例の断面図FIG. 3 is a sectional view of a busbar current measuring device according to another embodiment of the present invention.
【図４】図１に示す実施例による母線の電流測定器に関
連する他の実施例の断面図FIG. 4 is a cross-sectional view of another embodiment related to the bus current measuring device according to the embodiment shown in FIG.
【図５】従来の母線の電流測定器の断面図FIG. 5 is a cross-sectional view of a conventional bus current measuring device.
【符号の説明】 １ 母線 ２ 巻心 3a ，3b コイル 3a'，3b' コイル 3a"，3b" コイル 5a , 5b 負荷[Explanation of symbols] 1 bus bar 2 cores 3a, 3b coil 3a ', 3b' coil 3a ", 3b" coil 5a, 5b load
Claims (3)
記母線を中心として配設された絶縁物からなり実質的に
円環形状の巻心と、 前記巻心全周に実質的に等巻線密度で巻回した第１のコ
イルと、 前記第１のコイルの両端の間に電気的に接続された第１
の負荷と、 前記第１のコイルの外周に巻枠全周に実質的に等巻線密
度で巻回した少なくとも１つのコイルと、 前記少なくとも１つのコイルの各両端の間に電気的にそ
れぞれ接続された各負荷とを有し、 前記第１のコイル及び少なくとも１つのコイルのそれぞ
れに接続された前記各負荷を含むインピーダンスZLの値
は ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ) 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧(V)，Ｉ：被測定電流(A) に設定されていることを特徴とする母線の電流測定器。1. A substantially ring-shaped winding core made of an insulating material, which is arranged around the bus bar around which the current to be measured flows, and is substantially equal to the entire circumference of the winding core. A first coil wound at a winding density, and a first coil electrically connected between both ends of the first coil.
Load, at least one coil wound around the entire circumference of the first coil with substantially equal winding density, and electrically connected between both ends of the at least one coil, respectively. The value of the impedance Z L including each load connected to each of the first coil and at least one coil is Z L > N · E · (M−1) / ( 5 × 10 -3 · I) However, M: number of coils, N: number of turns of each coil, E: coil induced voltage (V), I: current measured (A) Current measuring device.
記母線を中心として配設された絶縁物からなり実質的に
円環形状の巻心と、 前記巻心上に同層で順次に巻回した複数のコイルと、 前記複数のコイルの各両端の間に電気的にそれぞれ接続
された各負荷とを有し、 前記複数のコイルの各両端の間に電気的にそれぞれ接続
された前記各負荷を含むインピーダンスZLの値は ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ) 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧(V)，Ｉ：被測定電流(A) に設定されていることを特徴とする母線の電流測定器。2. A substantially ring-shaped winding core made of an insulator arranged around the bus bar around which the current to be measured flows and a substantially circular ring-shaped core. A plurality of wound coils and each load electrically connected between both ends of the plurality of coils, respectively, the electrically connected between the respective ends of the plurality of coils The value of impedance Z L including each load is Z L > N ・ E ・ (M-1) / (5 × 10 -3・ I) where M: number of coils, N: number of turns of each coil, E: coil induced voltage (V), I: Bus current measuring device characterized by being set to the measured current (A).
記母線を中心として配設された絶縁物からなり実質的に
円環形状の巻心と、 前記巻心の母線円周方向に順番に巻回したコイルを１つ
のオープンループを形成して少なくとも１つおきに直列
に接続した複数のコイルと、 前記複数のコイルの外周に前記母線を中心として配設さ
れた導電材料のタンクと、 前記複数のコイルの各両端の間に電気的にそれぞれ接続
された各負荷とを有し前記複数のコイルの各両端の間に
電気的にそれぞれ接続された各負荷を含むインピーダン
スZLの値は ZL＞Ｎ・Ｅ・(M-1)／(5×10-3・Ｉ) 但し Ｍ：コイル数，Ｎ：各コイルの巻数， Ｅ：コイル誘起電圧(V)，Ｉ：被測定電流(A) に設定されていることを特徴とする母線の電流測定器。3. A substantially ring-shaped winding core made of an insulator arranged around the bus bar around which the current to be measured flows and a bus bar of the winding core in the circumferential direction. A plurality of coils in which one open loop is formed by connecting the coils wound on each other in series and at least every other coil is connected in series, and a tank of a conductive material arranged around the bus bar at the outer periphery of the plurality of coils, The value of the impedance Z L including the respective loads electrically connected between the respective ends of the plurality of coils and the respective loads electrically connected between the respective ends of the plurality of coils is Z L ＞ N ・ E ・ (M-1) / (5 × 10 -3・ I) where M: number of coils, N: number of turns of each coil, E: coil induced voltage (V), I: measured current ( Bus current measuring device characterized by being set to A).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23345492A JP3159541B2 (en) | 1992-09-01 | 1992-09-01 | Bus current meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23345492A JP3159541B2 (en) | 1992-09-01 | 1992-09-01 | Bus current meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0684672A true JPH0684672A (en) | 1994-03-25 |
| JP3159541B2 JP3159541B2 (en) | 2001-04-23 |
Family
ID=16955292
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23345492A Expired - Fee Related JP3159541B2 (en) | 1992-09-01 | 1992-09-01 | Bus current meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3159541B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6056995B2 (en) * | 2016-02-08 | 2017-01-11 | シヤチハタ株式会社 | Marking tools for bolts and nuts |
-
1992
- 1992-09-01 JP JP23345492A patent/JP3159541B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP3159541B2 (en) | 2001-04-23 |
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