JPH0542180B2 - - Google Patents
Info
- Publication number
- JPH0542180B2 JPH0542180B2 JP57209513A JP20951382A JPH0542180B2 JP H0542180 B2 JPH0542180 B2 JP H0542180B2 JP 57209513 A JP57209513 A JP 57209513A JP 20951382 A JP20951382 A JP 20951382A JP H0542180 B2 JPH0542180 B2 JP H0542180B2
- Authority
- JP
- Japan
- Prior art keywords
- power line
- carrier signal
- high frequency
- transformer
- frequency carrier
- 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
- 230000008054 signal transmission Effects 0.000 claims description 23
- 238000004804 winding Methods 0.000 claims description 18
- 230000005540 biological transmission Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 230000002238 attenuated effect Effects 0.000 description 4
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B2203/00—Indexing scheme relating to line transmission systems
- H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
- H04B2203/5404—Methods of transmitting or receiving signals via power distribution lines
- H04B2203/5416—Methods of transmitting or receiving signals via power distribution lines by adding signals to the wave form of the power source
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B2203/00—Indexing scheme relating to line transmission systems
- H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
- H04B2203/5462—Systems for power line communications
- H04B2203/5483—Systems for power line communications using coupling circuits
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B2203/00—Indexing scheme relating to line transmission systems
- H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
- H04B2203/5462—Systems for power line communications
- H04B2203/5491—Systems for power line communications using filtering and bypassing
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Interconnected Communication Systems, Intercoms, And Interphones (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Description
【発明の詳細な説明】
本発明は交流電力線上の交流電圧波形に重畳し
て高周波搬送信号を伝送するようにした電力線搬
送信号伝送システムに関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power line carrier signal transmission system that transmits a high frequency carrier signal superimposed on an AC voltage waveform on an AC power line.
この種の電力線搬送信号伝送システムは、例え
ばマンシヨンのような集合住宅の共同玄関や管理
人室等の共通部分に設けられた共用通話装置と、
各住戸ごとに設けられた個別通話装置との間で通
話を行うインタホンシステムに用いられている。
このインタホンシステムでは、共用通話装置と個
別通話装置との間をインタホン回線で接続し、各
通話装置間の通話路の切換をインタホン回線に挿
入され共同玄関、管理人室及び各住戸ごとに設け
られたスイツチで行う。そして、管理人室に設け
られた電源トランスにより降圧したAC24Vを交
流電力線を介して共同玄関及び各住戸に供給して
ある。ここで、交流電力線はインタホン回線と並
設してある。そして、この交流電力線に共同玄
関、管理人室及び各住戸に設けられ送信器及び受
信器からなる信号伝送ユニツトを接続し、各信号
伝送ユニツトの間で交流電力線上に高周波搬送信
号を重畳して信号伝送を行つて上記スイツチの切
換制御を行う。 This type of power line carrier signal transmission system uses a common communication device installed in a common area such as a common entrance or a manager's room of a housing complex such as a condominium.
It is used in intercom systems that communicate with individual communication devices installed in each residential unit.
In this intercom system, a common communication device and an individual communication device are connected by an interphone line, and the communication path between each communication device is inserted into the interphone line and installed at the common entrance, the manager's room, and each residential unit. This is done with a switch. Then, AC 24V, which has been stepped down by a power transformer installed in the manager's room, is supplied to the common entrance and each residence via an AC power line. Here, the AC power line is installed in parallel with the intercom line. Then, signal transmission units consisting of transmitters and receivers installed in the common entrance, the manager's room, and each dwelling unit are connected to this AC power line, and a high-frequency carrier signal is superimposed on the AC power line between each signal transmission unit. The switching control of the switch is performed by signal transmission.
例えば、この種の電力線搬送信号伝送システム
における信号伝送方式の一例としては、交流電源
の半サイクル区間を４分割し、各分割区間に高周
波搬送信号を重畳しているか否かでサブビツトデ
ータ「１」「０」を伝送し、この４個のサブビツ
トデータを制御信号として用い、この制御信号
（０，１，０，１）でスタートデータ、（０，１，
１，１）でビツトデータ“１”、（０，１，０，
０）ビツトデータ“０”、（０，１，１，０）でエ
ンドデータを表し、上記複数のビツトデータから
なる送信先の受信器を特定するアドレスデータ及
び制御内容を示す制御データの前後にスタートデ
ータ及エンドデータを付した伝送信号を送信器か
ら受信器に伝送する。 For example, as an example of a signal transmission method in this type of power line carrier signal transmission system, a half-cycle section of an AC power supply is divided into four sections, and sub-bit data "1" is determined depending on whether or not a high-frequency carrier signal is superimposed on each divided section. "0" is transmitted, and these four sub-bit data are used as control signals, and with this control signal (0, 1, 0, 1), start data, (0, 1,
1, 1), bit data “1”, (0, 1, 0,
0) End data is represented by bit data "0" and (0, 1, 1, 0), before and after the address data that specifies the destination receiver and the control data that indicates the control contents, which are made up of the above plurality of bit data. A transmission signal with start data and end data is transmitted from the transmitter to the receiver.
上記伝送信号を受信する受信器では、伝送信号
中のアドレスデータが自己の固有アドレスと一致
したとき、そのアドレスデータに続く制御データ
を取り込んでスイツチの切換制御を行う。 In the receiver that receives the transmission signal, when the address data in the transmission signal matches its own unique address, the receiver takes in the control data following the address data and controls switching of the switch.
第１図はかかる従来の電力線搬送信号伝送シス
テムの高周波信号に対する等価回路を示してい
る。第１図において、ZTは電源トランスの２次側
のインピーダンス、ZRは交流電力線１に接続され
る受信器２の内部インピーダンス、ZOは交流電力
線１に接続される送信器３の内部インピーダン
ス、EOは送信器３の高周波送信出力電圧を示し
ている。ただし、各インピーダンスZT，ZR，ZOは
いずれも高周波信号に対するインピーダンスであ
る。第１図から明らかなように受信器２における
受信電圧ERはZT≫ZRであるときには次式より与
えられる。 FIG. 1 shows an equivalent circuit for high frequency signals of such a conventional power line carrier signal transmission system. In Figure 1, Z T is the impedance of the secondary side of the power transformer, Z R is the internal impedance of the receiver 2 connected to the AC power line 1, and Z O is the internal impedance of the transmitter 3 connected to the AC power line 1. , E O indicates the high frequency transmission output voltage of the transmitter 3. However, each impedance Z T , Z R , and Z O are all impedances for high frequency signals. As is clear from FIG. 1, when Z T >>Z R , the received voltage E R at the receiver 2 is given by the following equation.
ER＝EO×ZR／ZO＋ZR ……(1)
しかしながら、一般の電源トランスにおいては
電圧振幅の大きな位相においては高周波信号に対
する２次側のインピーダンスZTは低下し、場合に
よつてはZT＜ZRとなることがある。したがつてこ
の場合における受信電圧ERは次式により与えら
れる。 E R =E O ×Z R /Z O +Z R ...(1) However, in general power transformers, the impedance Z T on the secondary side for high-frequency signals decreases in phases with large voltage amplitudes, and in some cases In some cases, Z T < Z R. Therefore, the received voltage E R in this case is given by the following equation.
ER＝EO×ZTZR／ZO＋ZTZR ……(2) ただし、ZTZR＝ZTZR／ZT＋ZRである。 E R =E O ×Z T Z R /Z O +Z T Z R ...(2) However, Z T Z R =Z T Z R /Z T +Z R.
上記(2)式におけるインピーダンスZTは、電源ト
ランスの電圧位相によつて変動するために、同一
レベルの送信出力に対して受信レベルは常に変動
することになる。第２図はこの様子を示す図であ
り、同図ａは交流電力線１上の交流電圧の全波整
流波形を示しており、同図ｂは送信器３により連
続的に同一レベルの高周波搬送信号を送信した場
合における受信器２の受信波形を示している。こ
の第２図ｂから明らかなように、交流電圧の電圧
振幅の大きな位相においては高周波信号の減衰が
大きくなり、したがつて受信器２における受信レ
ベルは周期的に変動して安定した信号伝送を行な
えないという問題があつた。また同一のトランス
に接続された交流電力線に複数個のシステムを接
続すると、高周波搬送信号の相互の干渉があるた
めにいずれのシステムも正常に動作し得ないとい
う問題があつた。 Since the impedance Z T in equation (2) above varies depending on the voltage phase of the power transformer, the reception level always varies for the same level of transmission output. FIG. 2 is a diagram showing this situation, in which figure a shows a full-wave rectified waveform of the AC voltage on the AC power line 1, and figure b shows a high-frequency carrier signal of the same level continuously transmitted by the transmitter 3. 2 shows the received waveform of the receiver 2 when transmitting. As is clear from FIG. 2b, the attenuation of the high-frequency signal becomes large in the phase where the voltage amplitude of the AC voltage is large, and therefore the reception level at the receiver 2 fluctuates periodically, ensuring stable signal transmission. I had a problem that I couldn't do it. Furthermore, when a plurality of systems are connected to an AC power line connected to the same transformer, there is a problem in that none of the systems can operate normally due to mutual interference of high frequency carrier signals.
本発明は従来例のこのような問題点を解決する
ために為されたものであり、交流電力線上に高周
波搬送信号を安定に伝送させ得るようにし、また
１つのトランスに複数個のシステムを接続しても
システム相互間の干渉が起こらないようにした電
力線搬送信号伝送システムを提供することを目的
とするものである。 The present invention was made in order to solve these problems of the conventional example, and makes it possible to stably transmit a high frequency carrier signal on an AC power line, and also to connect a plurality of systems to one transformer. It is an object of the present invention to provide a power line carrier signal transmission system in which interference between systems does not occur even when the power line carrier signal is transmitted.
以下本発明の構成を図示実施例について説明す
ると、第３図に示すように商用交流電源４に接続
された第１の交流電力線５降圧用のトランス６の
１次巻線７を接続し、ブロツクフイルタ８を介し
て上記トランス６の２次巻線９に第２の交流電力
線１０を接続し、交流電圧波形に重畳して高周波
搬送信号を伝送する信号伝送ユニツト１１，１２
を第２の交流電力線１０に接続し、ブロツクフイ
ルタ８では商用交流電源周波数の通過を許可する
とともに高周波搬送信号の通過を阻止し、ブロツ
クフイルタ８における第２の交流電力線１０との
接続端間のインピーダンスを高周波搬送信号に対
して高インピーダンスに設定したものである。信
号伝送ユニツト１１は送信器T1と受信器R2とか
ら構成されており、また信号伝送ユニツト１２は
送信器T1に対応する受信器R1と受信器R2に対応
する送信器T2とから構成されている。第４図は
ブロツクフイルタ８の構成の一例を示している。
同図に示すようにブロツクフイルタ８は高周波搬
送信号に共振せる一対の並列共振回路部１３と、
同じく高周波搬送信号に共振せる直列共振回路部
１４とからなり、一対の並列共振回路部１３の各
一端は夫々直列共振回路部１４の両端に接続さ
れ、その両接続点はトランス６の２次巻線９に接
続されるようになつている。また一対の並列共振
回路部１３の各他端は第２の交流電力線１０に接
続されるようになつている。したがつてブロツク
フイルタ８は高周波搬送信号に対して第２の交流
電力線１０の側は高インピーダンスとなり、また
トランス６の２次巻線９の側は低インピーダンス
となるものである。このため第２の交流電力線１
０上に高周波搬送信号を安定に伝送することがで
き、またトランス６の２次巻線９に複数個の電力
線搬送信号伝送システムを接続しても、トランス
６の２次巻線９の側の高周波信号は直列共振回路
部１４によつて減衰されるので、システム相互間
の干渉は生じないものである。第５図はブロツク
フイルタ８の他の一例を示すものであり、直列共
振回路部１４とトランス６の２次巻線９との間に
ノイズ吸収用フイルタ１５を設けたものである。
本実施例にあつては、交流電源４の側からノイズ
が混入したときに、高周波搬送信号に近い周波数
成分は直列共振回路部１４によつて減衰させ、他
の周波数成分はノイズ吸収用フイルタ１５によつ
て減衰せしめるものである。 The configuration of the present invention will be described below with reference to the illustrated embodiment. As shown in FIG. A second AC power line 10 is connected to the secondary winding 9 of the transformer 6 via the filter 8, and signal transmission units 11 and 12 transmit the high frequency carrier signal by superimposing it on the AC voltage waveform.
is connected to the second AC power line 10, and the block filter 8 allows the passage of the commercial AC power frequency and blocks the passage of the high frequency carrier signal. The impedance is set to a high impedance with respect to the high frequency carrier signal. The signal transmission unit 11 is composed of a transmitter T1 and a receiver R2, and the signal transmission unit 12 is composed of a receiver R1 corresponding to the transmitter T1 and a transmitter T2 corresponding to the receiver R2 . It is composed of. FIG. 4 shows an example of the structure of the block filter 8.
As shown in the figure, the block filter 8 includes a pair of parallel resonant circuit sections 13 that resonate with a high frequency carrier signal,
It also consists of a series resonant circuit section 14 that resonates with a high frequency carrier signal, one end of each of the pair of parallel resonant circuit sections 13 is connected to both ends of the series resonant circuit section 14, and both connection points are connected to the secondary winding of the transformer 6. It is designed to be connected to line 9. Further, each other end of the pair of parallel resonant circuit sections 13 is connected to the second AC power line 10. Therefore, the block filter 8 has a high impedance on the second AC power line 10 side with respect to the high frequency carrier signal, and a low impedance on the secondary winding 9 side of the transformer 6. Therefore, the second AC power line 1
Even if multiple power line carrier signal transmission systems are connected to the secondary winding 9 of the transformer 6, the high frequency carrier signal can be stably transmitted on the side of the secondary winding 9 of the transformer 6. Since the high frequency signal is attenuated by the series resonant circuit section 14, no interference occurs between the systems. FIG. 5 shows another example of the block filter 8, in which a noise absorbing filter 15 is provided between the series resonant circuit section 14 and the secondary winding 9 of the transformer 6.
In this embodiment, when noise enters from the AC power supply 4 side, frequency components close to the high frequency carrier signal are attenuated by the series resonant circuit section 14, and other frequency components are attenuated by the noise absorption filter 15. It is attenuated by
本発明は以上のように構成されており、商用交
流電源に接続された第１の交流電力線に降圧用の
トランスの１次巻線を接続し、ブロツクフイルタ
を介して上記トランスの２次巻線に第２の交流電
力線を接続し、交流電圧波形に重畳して高周波搬
送信号を伝送する信号伝送ユニツトを第２の交流
電力線に接続し、ブロツクフイルタでは商用交流
電源周波数の通過を許可するとともに高周波搬送
信号の通過を阻止し、ブロツクフイルタにおける
第２の交流電力線との接続端間のインピーダンス
を高周波搬送信号に対して高インピーダンスに設
定したものであるから、トランスの２次巻線によ
つて高周波搬送信号が減衰するようなことはな
く、またその減衰の程度が変動するようなことも
ないので、第２の交流電力線上に高周波搬送信号
を安定に伝送することができるという利点があ
る。すなわち、インタホン回線のような小勢力線
と給電用の交流電力線とを並設する場合には、商
用交流電源を降圧することが必要であつて、トラ
ンスによつて降圧したときに、トランスの２次巻
線のインピーダンスが商用交流電源周波数の周期
で変動し、トランスの２次側に接続されている信
号伝送ユニツトの間での高周波搬送信号の伝送に
支障が生じることになるが、本発明では、トラン
スの２次巻線のインピーダンスの変化が高周波搬
送信号の伝送に影響を与えないようにするため
に、信号伝送ユニツトが接続されている第２の交
流電力線と降圧用のトランスの２次巻線との間に
ブロツクフイルタを挿入し、ブロツクフイルタに
おける第２の交流電力線との接続端間のインピー
ダンスを高周波搬送信号に対して高インピーダン
スに設定しているのである。この構成の採用によ
つて、トランスの２次巻線のインピーダンス変動
の影響を受けることなく、第２の交流電力線に接
続された信号伝送ユニツト間での高周波搬送信号
の伝送が可能になるのである。また同一のトラン
スの２次巻線に夫々ブロツクフイルタを備える複
数個の電力線搬送信号伝送システムを接続して
も、高周波搬送信号はブロツクフイルタによつて
阻止されてトランスの２次巻線の側には伝送され
ないので、システム相互間の干渉が生じるような
ことはないという利点を有するものである。 The present invention is constructed as described above, in which the primary winding of a step-down transformer is connected to a first AC power line connected to a commercial AC power source, and the secondary winding of the transformer is connected via a block filter. A second AC power line is connected to the second AC power line, and a signal transmission unit that transmits a high frequency carrier signal by superimposing it on the AC voltage waveform is connected to the second AC power line.The block filter allows passage of the commercial AC power frequency and also transmits the high frequency carrier signal. This block filter prevents the passage of the carrier signal and sets the impedance between the connecting end of the block filter and the second AC power line to a high impedance with respect to the high-frequency carrier signal. Since the carrier signal does not attenuate and the degree of attenuation does not fluctuate, there is an advantage that the high frequency carrier signal can be stably transmitted on the second AC power line. In other words, when installing a small power line such as an intercom line and an AC power line for power supply in parallel, it is necessary to step down the voltage of the commercial AC power supply, and when the voltage is stepped down by a transformer, The impedance of the secondary winding fluctuates with the frequency of the commercial AC power supply, causing problems in the transmission of high-frequency carrier signals between the signal transmission units connected to the secondary side of the transformer. In order to prevent changes in the impedance of the secondary winding of the transformer from affecting the transmission of high-frequency carrier signals, the secondary winding of the step-down transformer is connected to the second AC power line to which the signal transmission unit is connected. A block filter is inserted between the power line and the second AC power line, and the impedance between the connection end of the block filter and the second AC power line is set to be high with respect to the high frequency carrier signal. By adopting this configuration, high-frequency carrier signals can be transmitted between signal transmission units connected to the second AC power line without being affected by impedance fluctuations in the secondary winding of the transformer. . Furthermore, even if a plurality of power line carrier signal transmission systems each having a block filter are connected to the secondary winding of the same transformer, the high frequency carrier signal is blocked by the block filter and transferred to the secondary winding of the transformer. is not transmitted, so it has the advantage that there is no interference between systems.
第１図は従来の電力線搬送信号伝送システムの
高周波信号に対する等価回路を示す回路図、第２
図は同上の動作波形図、第３図は本発明の１実施
例の回路図、第４図は同上に用いるブロツクフイ
ルタの一例を示す回路図、第５図は同上に用いる
ブロツクフイルタの他の例を示す回路図である。
４は交流電源、５は第１の交流電力線、６はト
ランス、７は１次巻線、８はブロツクフイルタ、
９は２次巻線、１０は第２の交流電力線、１１，
１２は信号伝送ユニツトである。
Figure 1 is a circuit diagram showing an equivalent circuit for high-frequency signals in a conventional power line carrier signal transmission system;
3 is a circuit diagram of one embodiment of the present invention, FIG. 4 is a circuit diagram showing an example of a block filter used in the above, and FIG. 5 is a circuit diagram of another block filter used in the same. FIG. 2 is a circuit diagram showing an example. 4 is an AC power supply, 5 is a first AC power line, 6 is a transformer, 7 is a primary winding, 8 is a block filter,
9 is a secondary winding, 10 is a second AC power line, 11,
12 is a signal transmission unit.
Claims (1)
に降圧用のトランスの１次巻線を接続し、ブロツ
クフイルタを介して上記トランスの２次巻線に第
２の交流電力線を接続し、交流電圧波形に重畳し
て高周波搬送信号を伝送する信号伝送ユニツトを
第２の交流電力線に接続し、ブロツクフイルタで
は商用交流電源周波数の通過を許可するとともに
高周波搬送信号の通過を阻止し、ブロツクフイル
タにおける第２の交流電力線との接続端間のイン
ピーダンスを高周波搬送信号に対して高インピー
ダンスに設定して成ることを特徴とする電力線搬
送信号伝送システム。1 Connect the primary winding of a step-down transformer to a first AC power line connected to a commercial AC power supply, connect a second AC power line to the secondary winding of the transformer via a block filter, A signal transmission unit that transmits a high frequency carrier signal superimposed on the voltage waveform is connected to the second AC power line, and the block filter allows the passage of the commercial AC power frequency and blocks the passage of the high frequency carrier signal. A power line carrier signal transmission system characterized in that the impedance between the connection ends with the second AC power line is set to a high impedance with respect to the high frequency carrier signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20951382A JPS5999827A (en) | 1982-11-30 | 1982-11-30 | Transmission system of power line carrier signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20951382A JPS5999827A (en) | 1982-11-30 | 1982-11-30 | Transmission system of power line carrier signal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5999827A JPS5999827A (en) | 1984-06-08 |
| JPH0542180B2 true JPH0542180B2 (en) | 1993-06-25 |
Family
ID=16574035
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20951382A Granted JPS5999827A (en) | 1982-11-30 | 1982-11-30 | Transmission system of power line carrier signal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5999827A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5668351A (en) * | 1979-11-07 | 1981-06-09 | Morinaga & Co Ltd | Preparation of granular freeze dried coffee having shape of coffee bean |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6123885Y2 (en) * | 1979-10-31 | 1986-07-17 |
-
1982
- 1982-11-30 JP JP20951382A patent/JPS5999827A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5668351A (en) * | 1979-11-07 | 1981-06-09 | Morinaga & Co Ltd | Preparation of granular freeze dried coffee having shape of coffee bean |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5999827A (en) | 1984-06-08 |
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