JPS593265A - Measurement of three-dimensional space electric field - Google Patents

Abstract

PURPOSE:To make it possible to calculate the effective value and the max. value of an electric field, by providing each one set of electrodes in three directions or two directions mutually crossed at right angles in an AC electric field to synthesize the square sum of AC induction currents flowing between each electrodes in a circuit forming manner. CONSTITUTION:In order to calculate the max. value of a space electric field, when the instantaneous values of currents flowing between electrodes A.A', B.B' and C.C' are respectively set to iA, iB and iC, the timewise max. value of a square sum i<2>=i<2>A+i<2>B+i<2>C may be calculated. As a measuring means, for example, a method, wherein each current components of iA, iB, iC detected by a current detecting resistor R are multiplied and added by an amplifier circuit having a square characteristic and the peak value thereof is indicated, can be employed. By this method, it becomes unnecessary that electrodes are provided in the direction at right angles relative to an electric field and three-dimensional electric field components are measured and added respectively separately while a measuring error based on the positional shift with the directions of each electric fields are not generated at all and three-dimensional electric field components can be measured simultaneously.

Description

【発明の詳細な説明】 本発明は設置電極の方向に無関係に、その点の電界を測
定できる三次元空間電界の測定方法に関するものである
。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring a three-dimensional spatial electric field that can measure the electric field at a point regardless of the direction of an installed electrode.

交流電界の測定法として、従来電界の方向と直角に、た
とえば２枚の平行平板電極を置き、電極間に流れる誘導
電流から求める方法や、電界に応じて偏波面が変るよう
な偏光素子を電極間に置いて、光学的に電界を測定する
方法が用いられている。しかしいずれの方法も、電極面
を電界の方向と直角に向けなければならないため、電界
の方向が未知の場合には、測定器の向きを変えて電界が
最大となるような方向を捜し求めなければならず、しか
も三次元電界の場合にはこれを三方向に亘って行わなけ
ればならない。このため測定操作が極めて煩雑であるば
かりでなく、空間の電界絶対値即ち電界の最大値、ある
いは実効値の正確な測定を困難にしている。Conventional methods for measuring alternating current electric fields include placing, for example, two parallel plate electrodes perpendicular to the direction of the electric field and obtaining the result from the induced current flowing between the electrodes, or using a polarizing element whose polarization plane changes depending on the electric field as the electrode. In the meantime, a method of optically measuring the electric field has been used. However, in both methods, the electrode surface must be oriented perpendicular to the direction of the electric field, so if the direction of the electric field is unknown, the direction of the measuring instrument must be changed to find the direction where the electric field is maximum. Moreover, in the case of a three-dimensional electric field, this must be done in three directions. This not only makes the measurement operation extremely complicated, but also makes it difficult to accurately measure the absolute value of the electric field in the space, that is, the maximum value of the electric field, or the effective value.

本発明は以上の点に鑑みてなされたもので、設置した電
極の方向に無関係に、その点の空間電界の実効値あるい
は最大値を正確かつ簡単に測定できる新しい電界測定法
を提供するもので、次に図面を用いてその詳細を説明す
る。The present invention has been made in view of the above points, and provides a new electric field measurement method that can accurately and easily measure the effective value or maximum value of the spatial electric field at a point, regardless of the direction of the installed electrode. Next, the details will be explained using the drawings.

第１図（ａ）（ｂ）は本発明の詳細な説明するための電
極の配置を示す斜視図、および平面図であって、交流電
界中の互に直交する三方向に、それぞれ２枚の平行平板
よりなる３組の電極Ａ　、　Ａ　、　Ｂ　、　１３およ
びＣ，Ｃ、を設け、各電極間に流れる誘導電流を合成す
ることによって、その点の電界を測定するもので、次に
これを更に詳細に説明する。FIGS. 1(a) and 1(b) are a perspective view and a plan view showing the arrangement of electrodes for detailed explanation of the present invention, in which two electrodes are placed in each of three mutually orthogonal directions in an alternating current electric field. Three sets of parallel plate electrodes A, A, B, 13 and C, C are provided, and the electric field at that point is measured by combining the induced current flowing between each electrode. This will be explained in more detail.

Ａ〕　空間ｒ１ｊ界の実効値の測定 いま、Ａ−Ａ方向の交流電界ＥＡ（実効値）があると、
電極Ａ、Ａ間に電界に比例した誘導電流　へ−ωε。Ｅ
ＡＳ（実効値）が流れる。こ５でＳは比例定数で、平板
電極の場合はほぼ電極面積である。またωは角周波数、
ε。は誘電率である。同様にＢ−Ｂ方向およびＣ−Ｃ方
向の電界があると、それぞれ電極Ｂ、Ｂ間、Ｃ１Ｃ間に
も誘導電流■８および１゜が流れる。従って、各方向の
誘導電流の実効値Ｉ、　　ｌ８Ｉｏの２乗を求めれば、
　Ｅ　−Ｉ　／　（ωε。Ｓ）より、電界の方向によら
ず、その点の電界実効値が測定できる。A] Measurement of the effective value of the spatial r1j field Now, if there is an AC electric field EA (effective value) in the A-A direction,
An induced current proportional to the electric field between electrodes A and A to −ωε. E
AS (effective value) flows. Here, S is a proportionality constant, and in the case of a flat electrode, it is approximately the electrode area. Also, ω is the angular frequency,
ε. is the dielectric constant. Similarly, when there is an electric field in the B-B direction and the C-C direction, induced currents 18 and 1° also flow between the electrodes B and B, and between C1C, respectively. Therefore, if we find the square of the effective value I of the induced current in each direction, l8Io, we get
From E-I/(ωε.S), the effective value of the electric field at that point can be measured regardless of the direction of the electric field.

また、三次元電界ではあるが、電界の一方向成分がＯで
あることがわかっているような場合、例えば充分長い送
電線の下の空間電界を測定する場合にも、本発明によっ
て容易に電界実効値を求めることができる。即ち電界の
存在する面にＡ、Ｂ二方向をとり、両方向に各１糾設置
した電極間に生ずる誘導電流の２乗和を合成ずればよい
。また以上におけるような電流実効値の２乗の和の測定
手段としては、例えば熱電式電流計の原理を用いる方法
を採用できる。例えば３方向の場合には、第２図に示す
ように電極間の抵抗Ｒに接した熱電対（ａ）（＋））（
Ｃ）を直列に接続し、その出力を計器Ｍにより読取るこ
とによって測定が可能である。Furthermore, even in cases where it is known that the unidirectional component of the electric field is O, although it is a three-dimensional electric field, for example, when measuring a spatial electric field under a sufficiently long power transmission line, the present invention can easily measure the electric field. The effective value can be determined. That is, two directions A and B are taken on the plane where the electric field exists, and the sum of the squares of the induced currents generated between the electrodes installed in each direction are synthesized. Further, as the means for measuring the sum of the squares of the effective current values as described above, for example, a method using the principle of a thermoelectric ammeter can be adopted. For example, in the case of three directions, the thermocouple (a) (+)) (
C) can be connected in series and the output can be read by a meter M.

従って本発明によれば、三次元の電界成分を別個に測定
し加算する従来方法と比べて、一度に測定できるため非
常に簡便であり、また従来のように電極を直角な三方向
に測定器を置くための難かしさから生ずる誤差も含まれ
ないので測定が正確となる。なお単相の電界では実効値
がそのまま最大値に比例するので、単相あるいは単相に
近い電界中（位相の異なる電界成分が小さいとき）では
、電界の最大値も測定できる。Therefore, according to the present invention, compared to the conventional method of measuring three-dimensional electric field components separately and adding them together, it is very simple because it can be measured all at once. The measurement is accurate because it does not include any errors caused by the difficulty of placing it. Note that in a single-phase electric field, the effective value is directly proportional to the maximum value, so in a single-phase or near-single-phase electric field (when electric field components with different phases are small), the maximum value of the electric field can also be measured.

Ｂ〕　空間電界の最大値の測定 　３− 位相および方向の異なる電界成分がある場合、Ａ〕項で
述べた実効値とその点の電界最大値とは比例しないので
、厳密には最大値を求めることができない。しかし、空
間電界を生ずる電源が多相の場合でも、各方向の誘導電
流の瞬時値の２乗和を測定すれば、空間電界の最大値が
測定できる。B] Measuring the maximum value of the spatial electric field 3- If there are electric field components with different phases and directions, the effective value mentioned in section A is not proportional to the maximum electric field value at that point, so strictly speaking, find the maximum value. I can't. However, even if the power source that generates the spatial electric field is multiphase, the maximum value of the spatial electric field can be measured by measuring the sum of the squares of the instantaneous values of the induced currents in each direction.

即ち第１図において、電極Ａ　、　Ａ間、Ｂ、Ｂ問およ
びＣ，０間を流れる電流の瞬時値を、それぞれＩＡＩＢ
おＪ二びＩ。としたとき、その２乗２　　　　２　　　
　２　　　　２ 和　１　−ＩＡ　＋ＩＢ　　」−１゜　の時間的な最大
値を求めればよい。その測定手段としては、例えば電流
検出抵抗Ｒによって検出されたｌＡ、　　ＩＢｌｏ　の
各電流成分を、２乗特性をもつ増幅回路を用いて増幅、
加算し、そのピーク値を指示する方法をとることができ
る。That is, in Fig. 1, the instantaneous values of the currents flowing between electrodes A and A, between electrodes B and B, and between electrodes C and 0 are expressed as IAIB.
Oh J Nibi I. Then, its square 2 2
What is necessary is to find the temporal maximum value of 2 2 sum 1 -IA +IB''-1°. As a measurement means, for example, each current component of lA and IBlo detected by the current detection resistor R is amplified using an amplifier circuit having a square characteristic.
A method can be used in which the values are added and the peak value is indicated.

以上本発明について説明したが、実用においては第３図
に示す平面図のように、３組の半球状型絶縁物■。によ
り互に直角となるように支持する　４− 構造を用い、各電極の誘導電流の合成値を指示計に接続
して測定する。この方法によれば電極が半球状であるの
で、測定感度を向」−できる。Although the present invention has been described above, in practical use, three sets of hemispherical insulators (1) are used, as shown in the plan view of FIG. 4- Using a structure in which the electrodes are supported at right angles to each other, the combined value of the induced current of each electrode is measured by connecting it to an indicator. According to this method, since the electrodes are hemispherical, the measurement sensitivity can be improved.

以上の説明から明らかなように、本発明にＪこれば従来
方法のように電界と直角な方向に電極を設置して、それ
ぞれ別箇に３次元の電界成分を測定して加算する必要が
全くないので、各電界の方向との位置ずれにもとづく測
定誤差を全く生ずることがなく、しかも一度に３次元の
電界成分を測定できるため、測定操作も非常に簡単とな
るすぐれた利点を有するもので、実用的効果は極めて大
きい。As is clear from the above explanation, if the present invention is applied, there is no need to install electrodes in a direction perpendicular to the electric field and measure and add each three-dimensional electric field component separately, as in the conventional method. Since there is no measurement error caused by positional deviation from the direction of each electric field, it also has the excellent advantage of being able to measure three-dimensional electric field components at once, making the measurement operation very simple. , the practical effects are extremely large.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図（ａ）（ｂ）は本発明の詳細な説明するための斜
視図および平面図、第２図は電流実効値の２乗の和を求
める測定方法の一例を示す回路図、第３図は実用的な電
極形状と電極配置を示す図である。 １１・・・・・抵抗、 ａ　、　ｈ　、　ｃ・・・・熱電対、 Ｍ・・・・ｄ１器、 ■　・・・・絶縁物。 特許出願人　　財団法人　電力中央研究所７− 躬　１　　閃 （ｂ） 躬　２　図1(a) and 1(b) are a perspective view and a plan view for explaining the present invention in detail, FIG. 2 is a circuit diagram showing an example of a measuring method for determining the sum of the squares of the effective current value, and FIG. The figure shows a practical electrode shape and electrode arrangement. 11...Resistance, a, h, c...Thermocouple, M...d1 device, ■...Insulator. Patent applicant: Central Research Institute of Electric Power Industry 7- Tsumugi 1 Sen (b) Tsumugi 2 Fig.

Claims (1)

【特許請求の範囲】[Claims] 交流電界中の互に直交する三方向または二方向に各１組
の電極を設けて、各電極間に流れる交流誘導電流の２乗
和を回路的に合成することによって、電界の実効値と最
大値を求めることを特徴とする三次元空間電界側、定方
法−By providing one set of electrodes in each of three or two directions orthogonal to each other in an AC electric field and synthesizing the sum of squares of the AC induced current flowing between each electrode in a circuit, the effective value and maximum value of the electric field can be calculated. Three-dimensional space electric field side, which is characterized by finding the value -