JPH0427505B2 - - Google Patents
Info
- Publication number
- JPH0427505B2 JPH0427505B2 JP56103654A JP10365481A JPH0427505B2 JP H0427505 B2 JPH0427505 B2 JP H0427505B2 JP 56103654 A JP56103654 A JP 56103654A JP 10365481 A JP10365481 A JP 10365481A JP H0427505 B2 JPH0427505 B2 JP H0427505B2
- Authority
- JP
- Japan
- Prior art keywords
- gate
- filter
- integrator
- antenna
- frequency
- 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 - Lifetime
Links
- 238000001514 detection method Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 9
- 230000010354 integration Effects 0.000 description 6
- 239000003990 capacitor Substances 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/02—Details
- H04B3/46—Monitoring; Testing
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Locating Faults (AREA)
Description
【発明の詳細な説明】
この発明は、高電圧パルス印加法による架空配
電線路の事故点の探査に使用する受信装置の改良
に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a receiving device used for detecting a fault point on an overhead power distribution line using a high voltage pulse application method.
架空配電線に接地事故が生じたときは、高電圧
パルス印加法により事故点の探査を行つている。
これは停電状態の線路区間に高電圧パルスを印加
し、配電線路を流れるパルス電流をアンテナ付き
の受信装置により検出して接地事故点の探査を行
うものである。 When a grounding fault occurs on an overhead power distribution line, the fault point is detected using the high-voltage pulse application method.
This involves applying a high voltage pulse to a section of line that is in a power outage state, and detecting the pulse current flowing through the distribution line using a receiver equipped with an antenna to locate the point of a ground fault.
このような探査原理を以下に説明する。第１図
は、接地事故点を探査している状態を示す図であ
る。図において、１は高電圧パルス発生器、２は
配電線路、３は大地、４は接地事故点、Rgは接
地事故抵抗、Cgは接地事故点以降の対地静電容
量、５は配電線に近接するサーチコイル形アンテ
ナ、６は受信装置、７はアンテナと受信装置６を
接続するリード線である。 The principle of such exploration will be explained below. FIG. 1 is a diagram showing a state in which a grounding accident point is being searched. In the figure, 1 is the high voltage pulse generator, 2 is the distribution line, 3 is the ground, 4 is the ground fault point, Rg is the ground fault resistance, Cg is the ground capacitance after the ground fault point, and 5 is close to the distribution line. 6 is a receiving device, and 7 is a lead wire connecting the antenna and the receiving device 6.
このような構成において、高電圧パルス発生器
１により配電線２と大地３との間に高電圧パルス
を印加し、アンテナ５付きの受信装置６で配電線
路２に流れる電流を検出して接地事故点を探査す
る。 In such a configuration, a high voltage pulse generator 1 applies a high voltage pulse between the power distribution line 2 and the ground 3, and a receiving device 6 equipped with an antenna 5 detects the current flowing through the power distribution line 2, thereby preventing a grounding accident. Explore points.
すなわち、第２図は高電圧パルス発生器１が発
生する電圧パルスの波形であり、この高電圧パル
スの印加により線路に流れる電流を１回積分すれ
ば
(イ) 線路に接地事故がない場合はその積分値は零
(ロ) 事故があつて、パルス発生器１からその事故
点までの区間では、その積分値は事故電流値
(ハ) 事故があつて、その事故点を通り過ぎた後の
区間ではその積分値は零
になるので、一定時間後に積分値を読み取ること
により上記３種類の値を判別して事故点の探査を
行なう。 In other words, Figure 2 shows the waveform of the voltage pulse generated by the high voltage pulse generator 1, and if the current flowing through the line due to the application of this high voltage pulse is integrated once, (a) If there is no grounding fault on the line, then The integral value is zero (b) In the section from pulse generator 1 to the fault point when an accident occurs, the integral value is the fault current value (c) The section after the fault occurs and passes the fault point Since the integral value becomes zero, the above three types of values are discriminated by reading the integral value after a certain period of time, and the accident point is searched.
しかしながらサーチコイル形のアンテナではア
ンテナ出力が線路電流波形を１回ある種の微分回
路を通したものと等価であるので、積分を２回行
なうことにより上記と同等の結果を得る。第３図
は従来の事故点探査用受信装置の一例で、８は増
幅器、９はゲート、１０は第１積分器、１１は第
２積分器、１２は検出表示ゲート、１３は検出メ
ーター、１４はゲート信号発生器である。 However, in the case of a search coil type antenna, the antenna output is equivalent to passing the line current waveform through a kind of differentiation circuit once, so the same result as above can be obtained by performing the integration twice. FIG. 3 shows an example of a conventional receiving device for fault point detection, in which 8 is an amplifier, 9 is a gate, 10 is a first integrator, 11 is a second integrator, 12 is a detection display gate, 13 is a detection meter, 14 is a gate signal generator.
このような、受信装置６の動作波形について説
明すると第４図は線路に事故がない場合、第５図
は線路に事故があつて高電圧パルス発生器１から
その事故点までの区間の場合、第６図は事故点以
降の場合で、それぞれａは線路電流、ｂはアンテ
ナ出力、ｇ１はゲート信号発生器１４のゲート９
への信号、ｃは第１積分器１０の出力、ｄは第２
積分器１１の出力、ｇ０はゲート信号発生器１４
の検出表示ゲート１２への信号、ｅは検出メータ
１３の振れである。 To explain the operating waveforms of the receiving device 6, FIG. 4 shows the waveform when there is no accident on the line, and FIG. Figure 6 shows the case after the fault point, where a is the line current, b is the antenna output, and g1 is the gate 9 of the gate signal generator 14.
c is the output of the first integrator 10, d is the signal of the second
Output of integrator 11, g0 is gate signal generator 14
The signal e to the detection display gate 12 is the deflection of the detection meter 13.
次に受信装置６の動作について説明する。アン
テナ５からの出力信号を増幅器８で充分な大きさ
に増幅し、この信号の最初の時点をゲート信号発
生器１４が検出し、高電圧パルスのパルス幅より
長い時間ゲート９を開き、第１、第２積分器１
０，１１により２回積分を行う。次に一定時間後
検出表示ゲート１２を開き、検出メータ１３によ
り事故の状態を判別する。 Next, the operation of the receiving device 6 will be explained. The output signal from the antenna 5 is amplified to a sufficient magnitude by an amplifier 8, and the gate signal generator 14 detects the first point in time of this signal and opens the gate 9 for a time longer than the pulse width of the high voltage pulse. , second integrator 1
Integrate twice using 0 and 11. Next, after a certain period of time, the detection display gate 12 is opened, and the detection meter 13 determines the state of the accident.
ところで数KΩ以上の高抵抗事故では、上記配
電線路電流の積分値が非常に小さくなり、近隣の
配電線に高次の高調波成分を含んだ大きな商用周
波電流が流れている場所、例えば、複雑で大きな
迷走電流が共同地線に流れる区間、あるいは、特
異な負荷を多数有する系統が含まれる２重架線区
間等では、商用周波やこれに重畳する高次の高調
波成分が上記の抵抗事故の積分値より非常に大き
くなるため探査が不正確になり、アンテナと事故
線路の距離関係によつては、探査が全く不可能に
なることがあつた。 However, in the case of a high resistance fault of several kilohms or more, the integrated value of the distribution line current becomes extremely small. In sections where a large stray current flows through the common ground wire, or in sections with double overhead lines that include a system with many unique loads, the commercial frequency and high-order harmonic components superimposed on it may cause the above-mentioned resistance fault. Since the value was much larger than the integral value, exploration became inaccurate, and depending on the distance between the antenna and the faulty line, exploration was sometimes impossible.
この発明は従来のものの欠点を除去するために
なされたもので、複数のフイルターを組み合せ受
信機に設置し、商用周波およびその高調波成分を
除去する機能を受信機に設けて、高調波成分を含
んだ商用周波電流が流れている区間でも、高抵抗
事故が極めて良好に探査できる受信装置を提供す
ることを目的としている。 This invention was made in order to eliminate the drawbacks of the conventional ones. Multiple filters are installed in a combination receiver, and the receiver is equipped with a function to remove commercial frequencies and their harmonic components. It is an object of the present invention to provide a receiving device that can extremely effectively detect high resistance faults even in sections where commercial frequency currents containing high-resistance faults are flowing.
以下この発明の一実施例について説明する。第
７図はこの発明の配電線事故点探査用受信装置１
５の一例を示すブロツク図で、１６はフイルター
で、第３図の従来の受信装置６における増幅器
８とアンテナ５の間に前記フイルター１６が挿入
された構成となつている。また、１７，１８は並
列に接続されるフイルター，で、増幅器８と
第１ゲート９の間にこれらのフイルター１７，１
８が挿入された構成となつている。２０は第２ゲ
ート、２１は減算器である。 An embodiment of this invention will be described below. FIG. 7 shows a receiving device 1 for detecting fault points in distribution lines according to the present invention.
5, 16 is a filter, and the filter 16 is inserted between the amplifier 8 and the antenna 5 in the conventional receiving device 6 of FIG. Further, 17 and 18 are filters connected in parallel, and these filters 17 and 18 are connected between the amplifier 8 and the first gate 9.
8 has been inserted. 20 is a second gate, and 21 is a subtracter.
次にこの受信装置の動作について説明する。フ
イルター１６は、減算増幅器、抵抗、コンデン
サから構成されて帯域消去形のアクテイブフイル
ターで、この場合、商用周波数fcを中心周波数に
選ぶ。 Next, the operation of this receiving device will be explained. The filter 16 is a band elimination type active filter composed of a subtracting amplifier, a resistor, and a capacitor, and in this case, the commercial frequency fc is selected as the center frequency.
第８図はフイルターの減衰比の周波数特性の例
で、実線で示すカーブが、フイルター１６の特
性である。この場合、構成部品の性能によつて
は、−数＋dB〜−百十dB程度の減衰特性が得ら
れる。このためフイルターの作用により単に商
用周波成分だけを大幅に減衰させることができ、
大電流の商用周波に対する影響を非常に小さくで
きる。 FIG. 8 shows an example of the frequency characteristic of the damping ratio of the filter, and the curve shown by the solid line is the characteristic of the filter 16. In this case, depending on the performance of the component parts, an attenuation characteristic of about -several +dB to -100 dB can be obtained. Therefore, only the commercial frequency component can be significantly attenuated by the action of the filter.
The influence of large currents on commercial frequencies can be minimized.
また、フイルター１７は高域通過フイルタ
ー、フイルター１８は低域通過フイルターで同
様に演算増幅器、抵抗、コンデンサから構成され
るアクテイブフイルターである。この場合高域通
過フイルターのフイルター１７のしや断周波数
は、商用周波数fcに含まれる高次の高調波周波数
fh例えば、第11調波〜第13調波程度に選び低域通
過フイルターのフイルター１８のしや断周波数
は商用周波数fc付近に選ぶ。尚第８図において、
fcは商用周波数、fhは高調波周波数、斜線部は通
過領域を示している。 Further, the filter 17 is a high-pass filter, and the filter 18 is a low-pass filter, which is also an active filter composed of an operational amplifier, a resistor, and a capacitor. In this case, the cutoff frequency of the filter 17 of the high-pass filter is the higher harmonic frequency included in the commercial frequency fc.
For example, fh is selected to be around the 11th to 13th harmonic, and the cutting frequency of the filter 18 of the low-pass filter is selected to be around the commercial frequency fc. In addition, in Figure 8,
fc indicates the commercial frequency, fh indicates the harmonic frequency, and the shaded area indicates the pass region.
第８図の破線で示すカーブがフイルター１７
の特性、一点鎖線で示すカーブがフイルター１
８の特性で、これらフイルター１６、１７、
１８を合わせた特性は周波数帯域が非常に広い
一種の帯域除去フイルターに等価で、商用周波成
分に含まれる基本波から数次の高調波成分を大き
く減衰させ、その影響を小さくできる。この減衰
の効果は特に基本波成分に対し最も顕著となる。 The curve shown by the broken line in Fig. 8 is the filter 17.
The curve shown by the dashed line is filter 1.
With the characteristics of 8, these filters 16, 17,
The combined characteristics of 18 are equivalent to a type of band rejection filter with a very wide frequency band, and can greatly attenuate harmonic components of several orders from the fundamental included in commercial frequency components, thereby reducing their influence. The effect of this attenuation is particularly noticeable for the fundamental wave component.
一方事故探査時に高電圧パルス発生器１から流
れるパルス電流は、フイルター１６，１７，１８
の影響により、その通過出力波形ｆは多少変歪す
るようになるが、第８図の斜線で示すように直流
成分は減衰なくそのまま通過する特性を有してい
るので、本受信装置のような完全積分形の受信装
置の探査性能は全く変化しない。第４、第５、第
６図に対応する本願の発明による受信装置１５の
動作波形をそれぞれ第９、第１０、第１１図に示
しているが、検出メーターの指示ｅはフイルター
１６，１７，１８が付加されても何ら変化しない
ことを示している。 On the other hand, the pulse current flowing from the high voltage pulse generator 1 during accident investigation is passed through the filters 16, 17, 18.
Due to the influence of The search performance of the fully integral receiver does not change at all. The operating waveforms of the receiving device 15 according to the invention of the present application corresponding to FIGS. 4, 5, and 6 are shown in FIGS. 9, 10, and 11, respectively. This shows that there is no change even if 18 is added.
アンテナ５からフイルター１６、増幅器８、
フイルター１７、フイルター１８を通つた信
号の最初の時点をゲート信号発生器１４が検出し
て一連のゲート信号を発生する。まず、受信時点
から高電圧パルスの時間幅より長い時間第１ゲー
ト９を一定期間開きフイルター出力ｆを通過させ
る。次に（第１ゲート出力）−（第２ゲート出力）
の減算機能を持つた減算器２１を経由して、第１
積分器１０、第２積分器１１で２回積分をする。
次に第１ゲート９を閉じた時点から、短時間に例
えば10μs程度第１積分器１０の積分内容を初期状
態に戻す。 From the antenna 5 to the filter 16, the amplifier 8,
A gate signal generator 14 detects the first point in time of the signal passing through the filters 17 and 18 and generates a series of gate signals. First, from the time of reception, the first gate 9 is opened for a certain period of time longer than the time width of the high voltage pulse to allow the filter output f to pass through. Next (1st gate output) - (2nd gate output)
The first
Integration is performed twice by the integrator 10 and the second integrator 11.
Next, from the time when the first gate 9 is closed, the integration contents of the first integrator 10 are returned to the initial state within a short time, for example, about 10 μs.
次に最初の受信時点から商用周波数周期の整数
倍の時間遅らして、第１ゲートと同じ時間第２ゲ
ート２０を開き、フイルター出力ｆを減算器２１
により極性反転（第１ゲート９が閉じているた
め）して第１ゲート９が開のときと同様に２回積
分する。次に高電圧パルス印加周期より短い時間
検出表示ゲート１２を開き、検出メータ１３に第
２積分器１１の内容を指示する。 Next, the second gate 20 is opened for the same time as the first gate with a delay of an integral multiple of the commercial frequency period from the first reception time, and the filter output f is sent to the subtracter 21.
The polarity is reversed (because the first gate 9 is closed) and integration is performed twice in the same way as when the first gate 9 is open. Next, the detection display gate 12 is opened for a time shorter than the high voltage pulse application period, and the content of the second integrator 11 is indicated to the detection meter 13.
この受信装置１５の商用周波成分を除いた動作
波形は前記第９、第１０、第１１により説明でき
るので、ここでは省略し、商用周波成分除去性能
を第１２図に説明する。図において、ｆはフイル
ター出力に残留する商用周波成分に、一例として
第３高調波成分が重畳した例を示している。信号
受信時間T1である第１ゲート９の開区間ｇ１は、
この例では特に商用周波数の周期の整数倍として
ものであるため、高調波成分があつても第１積分
器の出力ｃは第１ゲート９が閉じる時点では零と
なつている。しかし第２積分器の出力ｄは第１ゲ
ート９が閉じる時点である値を持つ、ｇ３は積分
休止区間で、このとき第１積分器１３は初期状態
に戻されるが、積分器は零であるためｄは変化し
ない。 The operating waveforms of this receiver 15 excluding the commercial frequency component can be explained by the ninth, tenth, and eleventh sections, so they are omitted here, and the commercial frequency component removal performance will be explained with reference to FIG. In the figure, f indicates an example in which a third harmonic component is superimposed on the commercial frequency component remaining in the filter output. The open section g1 of the first gate 9, which is the signal reception time T1 , is
In this example, the output c of the first integrator is zero at the time when the first gate 9 closes, even if there is a harmonic component, since it is an integral multiple of the period of the commercial frequency. However, the output d of the second integrator has a certain value when the first gate 9 closes, and g3 is an integration pause interval, at which time the first integrator 13 is returned to its initial state, but the integrator is zero. Therefore, d does not change.
次に商用周波数の周期の整数倍の時間T2遅ら
して第２ゲート２０を開く、このときの第２ゲー
ト２０のゲート開区間ｇ２は第１ゲート９の開区
間ｇ１と同一の信号受信時間T1であるため、減
算器１２により極性が反転され第２ゲート２０が
閉じる時点で最終の積分値は零となる。 Next, the second gate 20 is opened after a time T 2 that is an integral multiple of the period of the commercial frequency, and the gate open period g2 of the second gate 20 at this time is the same signal reception time as the open period g1 of the first gate 9. Since T 1 , the polarity is inverted by the subtracter 12 and the final integrated value becomes zero at the time when the second gate 20 closes.
また、第１ゲートの開区間が商用周波数の零以
外の位相で始まるとき、または開区間が商用周波
数の周期の整数倍以外のときは、上記のように第
１積分器の出力は第１ゲートが閉じるときに零に
はならない。しかし、第１積分器の入力波形は、
第１ゲートが開区間の時と第２ゲートが開区間の
時では、波形の形状が同じで極性のみが反転して
いるため、第１積分器の出力波形も積分波形の形
状が同じで極性のみが反転する。第２積分器はこ
の積分波形をすべて積分するため、最終の積分値
は零となり、商用周波数及びその高調波成分の除
去が可能である。 In addition, when the open interval of the first gate starts at a phase other than zero of the commercial frequency, or when the open interval is other than an integral multiple of the period of the commercial frequency, the output of the first integrator is does not become zero when it closes. However, the input waveform of the first integrator is
When the first gate is in the open section and when the second gate is in the open section, the waveform shape is the same and only the polarity is reversed, so the output waveform of the first integrator also has the same integration waveform shape and polarity. only is reversed. Since the second integrator integrates all of this integrated waveform, the final integrated value becomes zero, making it possible to remove the commercial frequency and its harmonic components.
以上のように、この出願の発明によれば、商用
周波数電流による影響の除去機能を受信装置に具
備させたので、２重架線区間等、高調波成分を含
む商用周波電流の影響を受け易い所でも、極めて
良好に高抵抗事故の探査ができるようになつた。 As described above, according to the invention of this application, since the receiving device is equipped with a function to remove the influence of commercial frequency current, places that are easily affected by commercial frequency current including harmonic components, such as double overhead line sections, However, it has become possible to search for high-resistance accidents extremely well.
第１図は接地事故点を探査している状態を示す
図、第２図は第１図の高電圧パルス発生器の高電
圧パルスの波形を示す図、第３図は従来の事故点
探査用受信装置のブロツク図、第４図、第５図、
第６図は探査原理を示す動作波形図、第７図はこ
の発明の受信装置のブロツク図、第８図は第７図
に示した受信装置に使用されるフイルターの周波
数特性、第９図、第１０図、第１１図は第７図に
示した受信装置の探査原理を示す動作波形図であ
る。第１２図は商用周波数の除去原理を示す図で
ある。
図において、５はアンテナ、１５及び１９は受
信装置、８は増幅器、９は第１ゲート、２０は第
２ゲート、１０は第１積分器、１１は第２積分
器、１３は検出メータ、１４はゲート信号発生
器、１６は帯域消去フイルタ、１７は高域通過フ
イルタ、１８は低域通過フイルタ、２１は減算器
である。なお、図中、同一符号は同一または相当
部分を示す。
Figure 1 is a diagram showing the state in which a ground fault point is being searched, Figure 2 is a diagram showing the waveform of the high voltage pulse of the high voltage pulse generator of Figure 1, and Figure 3 is a diagram showing the state in which the ground fault point is being searched. Block diagram of the receiving device, Fig. 4, Fig. 5,
FIG. 6 is an operating waveform diagram showing the principle of exploration, FIG. 7 is a block diagram of the receiving device of the present invention, FIG. 8 is the frequency characteristic of the filter used in the receiving device shown in FIG. 7, and FIG. 10 and 11 are operational waveform diagrams showing the principle of exploration of the receiver shown in FIG. 7. FIG. 12 is a diagram showing the principle of removal of commercial frequencies. In the figure, 5 is an antenna, 15 and 19 are receiving devices, 8 is an amplifier, 9 is a first gate, 20 is a second gate, 10 is a first integrator, 11 is a second integrator, 13 is a detection meter, 14 1 is a gate signal generator, 16 is a band elimination filter, 17 is a high-pass filter, 18 is a low-pass filter, and 21 is a subtracter. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.
Claims (1)
線に繰返し印加される高電圧パルスに基いて上記
配電線に流れるパルス電流をアンテナにより検出
して配電線に事故点を探査する受信装置におい
て、上記アンテナで受信した信号の商用周波数成
分だけを減衰させる第１のフイルターと、上記第
１のフイルターの出力側に接続した増幅器と、上
記増幅器の出力側に並列接続され、上記商用周波
数に含まれる高次の高調波周波数をしや断周波数
とする第２のフイルタおよび該商用周波数付近に
しや断周波数を選んだ第３のフイルタと、上記第
２のフイルタおよび第３のフイルタの出力側に並
列に配置された第１および第２のゲートと、これ
ら第１および第２ゲートを通過した信号を減算す
る減算器と、この減算された信号を２回積分する
直列に接続された２個の積分器と、この積分器出
力を指示する表示器と、上記アンテナで受信した
信号の開始時から上記高電圧パルスのパルス幅よ
り大である時間上記第１ゲートを開かせ、更に上
記アンテナで受信した信号の開始時から商用周波
数の周期の整数倍の時間遅らせて上記第１ゲート
と同じ時間上記第２ゲートを開かせるゲート信号
発生器とを備えた受信装置。1. In a receiving device that detects a pulse current flowing through the distribution line based on high voltage pulses repeatedly applied to the distribution line using an antenna to search for a failure point on the distribution line. , a first filter that attenuates only the commercial frequency component of the signal received by the antenna; an amplifier connected to the output side of the first filter; a second filter whose shedding frequency is a high-order harmonic frequency selected as the shedding frequency; a third filter whose shedding frequency is selected near the commercial frequency; First and second gates arranged in parallel, a subtracter that subtracts the signals passed through these first and second gates, and two serially connected gates that integrate the subtracted signal twice. an integrator, an indicator for indicating the output of the integrator, and an integrator for opening the first gate for a period of time greater than the pulse width of the high voltage pulse from the start of the signal received by the antenna, and further for receiving the signal by the antenna. and a gate signal generator that opens the second gate for the same time as the first gate by delaying the time by an integral multiple of the period of the commercial frequency from the start of the signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56103654A JPS585676A (en) | 1981-07-02 | 1981-07-02 | Receiving apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56103654A JPS585676A (en) | 1981-07-02 | 1981-07-02 | Receiving apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS585676A JPS585676A (en) | 1983-01-13 |
| JPH0427505B2 true JPH0427505B2 (en) | 1992-05-12 |
Family
ID=14359762
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56103654A Granted JPS585676A (en) | 1981-07-02 | 1981-07-02 | Receiving apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS585676A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01313779A (en) * | 1988-06-14 | 1989-12-19 | Hitachi Cable Ltd | Fault section detecting device for underground transmission line |
| JP2972408B2 (en) * | 1991-09-20 | 1999-11-08 | 三菱電機株式会社 | Substrate equipment |
| JP4853699B2 (en) * | 2005-03-30 | 2012-01-11 | 東京電力株式会社 | Electric charge type accident investigation device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5331251A (en) * | 1976-09-06 | 1978-03-24 | Toshiba Mach Co Ltd | Heat pipe sealing method |
| JPS5576292A (en) * | 1978-12-05 | 1980-06-09 | Tlv Co Ltd | Disc type steam trap |
| JPS634148A (en) * | 1986-06-25 | 1988-01-09 | 松下電工株式会社 | Structure of ceiling panel |
-
1981
- 1981-07-02 JP JP56103654A patent/JPS585676A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5331251A (en) * | 1976-09-06 | 1978-03-24 | Toshiba Mach Co Ltd | Heat pipe sealing method |
| JPS5576292A (en) * | 1978-12-05 | 1980-06-09 | Tlv Co Ltd | Disc type steam trap |
| JPS634148A (en) * | 1986-06-25 | 1988-01-09 | 松下電工株式会社 | Structure of ceiling panel |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS585676A (en) | 1983-01-13 |
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