JP2008219073A - Power supply adaptor for passing power communication signal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit and receive a power line communication signal by the power supply adaptor between an electric outlet and a terminal unit. <P>SOLUTION: The power supply adaptor supplies DC power by inserting an AC plug into the electric outlet and by connecting a DC connector to the terminal unit, and passes the power communication signal. The power supply adaptor has a power supply circuit 32 and a detour 26. The power supply circuit 32 is connected to the AC plug for converting to a prescribed AC voltage, converts AC to DC, absorbs the ripple of an AC component for connecting to the DC connector, and allows a side connected to the AC plug to be in a balance type and a side connected to the DC connector to be in an unbalanced type. The detour 26 is in parallel with the power supply circuit, includes a plurality of capacitors 28, 29, 30 connected between an AC-plug side and a DC-connector side and a balance-unbalance converter 27, eliminates AC components, and has a high-pass filter function for passing the power communication signal from the AC plug to the DC connector, or from the DC connector to the AC adaptor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power adapter that converts AC power and supplies DC power to a terminal device. In particular, the present invention relates to a power adapter for passing power line communication signals.

  FIG. 4 is a diagram showing a schematic shape of a power adapter as a premise of the present invention. In addition, the same number and code | symbol are attached | subjected to the same component through all the figures. As shown in the figure, the power adapter has a main body 20, an AC (alternating current) plug 21, and a DC (direct current) connector 25. The AC plug 21 is directly mounted on the main body 20, connected to an outlet, and the DC connector 25 is The AC power is converted to the target terminal device via the cord between the main body 20 and the DC power is supplied.

  FIG. 5 is a diagram showing an example of supplying DC power by the power adapter of FIG. 4 when charging a mobile phone. An AC plug 21 attached to the main body 20 is inserted into the outlet 10, and the main body 20 of the power adapter is directly connected to the outlet 10. In the power adapter, the cord extending from the main body 20 is connected to the desktop holder by the DC connector 25. When the mobile phone 11 is set in the desktop holder, DC power is supplied from the outlet 10 through the main body 20 of the power adapter. 11 is charged.

  FIG. 6 is a diagram showing an example of the power adapter of FIG. 4 when DC power is supplied to a notebook personal computer. As shown in the figure, in the power adapter, a cord is provided between the main body 20 and the AC plug 21, the AC plug 21 is connected to the outlet 10, and direct current power is supplied to the notebook personal computer 12 through the main body 20 of the power adapter. It is a mechanism to supply.

As described above, in the case of a terminal device that is originally operated by a battery, such as the mobile phone 11 and the notebook personal computer 12, the power supply is supplied from the outlet 10 of the power line via the external power adapter, and the internal battery is operated. Is charging.
Therefore, in order to communicate with these devices using power line communication (PLC: Power Line Communication) in the future, it is natural that the PLC signal needs to be exchanged through the power adapter.

  The power adapter having a function of passing a power line communication (PLC) signal, which is a premise of the present invention, is particularly a notebook personal computer 12, a mobile phone 11, and other portable devices, usually a battery. However, when charging, it is a device that is operated indoors by being supplied with DC power from an AC power line through the power adapter.

Power line communication PLC
http: /www.plc-j.org/about_plc_j.htm
http: /www.plc-j.org/about_highspeed_plc.htm
As described on the website, etc., information between devices that use the same power line as a power source by placing an information signal on the power line (or power line) normally used in homes and offices It communicates.

For example, by connecting a personal computer and a household electrical appliance, it becomes possible to manage a television and a refrigerator with the personal computer.
Further, the connection between the modem and the terminal device for the Internet connection can be realized without a cable other than the power line and wireless communication means through the outlet.
This simplifies wiring in the home and office.

Furthermore, there is an advantage that a terminal device can be installed and connected to the Internet wherever there is an outlet.
However, in the case of a device that obtains power from the outlet 10 via a power adapter, such as a notebook personal computer 12 or a mobile phone 11, the following problems occur when receiving a PLC signal directly.

  The PLC signal is a signal for sending information by superimposing it on an AC voltage through a power line (in the case of Japan, 100 V at 50 Hz to 60 Hz). There are several standards (for example, HD-PLC system, UPA standard of Spanish DS), but generally, in a high frequency band much higher than the frequency of AC voltage, OFDM (Orthogonal Frequency Division Multiplexing), An information signal is placed using frequency modulation or the like.

In the case of HD (High Definition) -PLC, an information signal is carried by OFDM modulation between about 2 MHz and 30 MHz, and a transmission speed of about 190 Mbps at the maximum is aimed at. For details of the HD-PLC method,
http://www.isit.or.jp/lab2/itoffice/2006/0131_3/PLC_060131.ppt
Can be referred to.

For details of UPA (Universal Powerline Association),
http://bb.watch.impress.co.jp/cda/news/16410.html
Can be referred to.
FIG. 7 is a diagram illustrating frequency characteristics of the PLC signal. As shown in the figure, the frequency of the AC power supply is 50 Hz to 60 Hz, but the frequency of the PLC signal is much higher and is distributed in the frequency range of 2 MHz to 30 MHz. As a modulation method, OFDM, spread spectrum modulation, or the like is used.

Therefore, the power adapter is required to pass the PLC signal in the high frequency band. However, a general power adapter has the following circuit configuration.
FIG. 8 is a circuit diagram showing a schematic configuration of a power adapter as a premise of the present invention. As shown in the figure, the main body 20 of the power adapter includes a transformer 22, a rectifier circuit 23, and a smoothing circuit 24. AC power (in Japan, 100 V at 50 Hz to 60 Hz) is supplied to the main body 20 of the power adapter from the AC plug 21 connected to the outlet 10.

  AC power is supplied from the AC plug 21 to the primary side of the transformer 22, converted to a predetermined AC voltage on the secondary side of the transformer 22, further converted to DC by the rectifier circuit 23, and one side of the balanced line is grounded Further, the smoothing circuit 24 absorbs the ripple of the AC component, and DC power is supplied from the DC connector 25 to the terminal device. In this case, the AC plug 21, the transformer 22, and the input side of the rectifier circuit 23 are balanced, and the output side of the rectifier circuit 23, the smoothing circuit 24, and the DC connector 25 are unbalanced.

In other words, the power adapter takes in AC power from a power line into a terminal device that is originally operated by a DC power source such as a battery, converts the AC power into a predetermined DC voltage, and supplies the DC power.
Of course, in addition to this, a fuse for safety and a surge absorber for lightning protection may be included, but the description is omitted because it is not directly related to the present invention.

However, the transformer 22, the rectifier circuit 23, and the smoothing circuit 24 shown in this drawing have extremely poor high-frequency band transmission characteristics, and the PLC signal has a problem that it is significantly attenuated by passing through these.
Therefore, if a conventional general power adapter is used, it is impossible to exchange PLC signals between the outlet 10 and the terminal device.

The following are related arts related to the power adapter that is the premise of the present invention.
Conventionally, in order to realize power line communication that has a simple configuration and can be easily connected in spite of the use of an AC-DC adapter, the notebook computer and the AC-DC adapter are connected by a DC power cable, and the AC-DC adapter is connected to the AC-DC adapter. By connecting the power cable to the AC outlet, the notebook PC is powered. Also, the AC-DC adapter receives the communication signal sent from the AC outlet via the AC power cable and the direct current. In addition, the DC power cable is used to send the signal to the notebook computer. Conversely, the communication signal sent from the notebook computer via the DC power cable with the direct current is sent with the AC-DC adapter. Some of them are designed to be received, switched to AC, and sent to an AC outlet using an AC power cable. (E.g., see Patent Document 1).

  However, Patent Document 1 describes that a communication signal sent by alternating current is replaced with direct current, and conversely, a communication signal sent by direct current is replaced by alternating current. To achieve this, referring to the diagram of Patent Document 1, all terminals for taking out power line communication signals on the AC side are taken from the same side of the balanced line, and capacitors C1, resistors R1, transformers T1, and capacitors C2 are connected. The power line communication signal cannot be sent to the DC side because the potential difference between two points of the same potential on the AC side (and therefore always 0v) is taken out. There is a problem in that it is unclear how the power line communication signal should be sent to the DC side, and vice versa.

  Conventionally, a balancing circuit in a communication line that can improve the balance of the communication line and superimpose an ideal normal mode signal on the communication line, thereby preventing radiation noise in the communication line. In order to provide a communication device, a plurality of connection points are provided in the middle of the secondary winding of the balun transformer, and the connection points are controlled so as to reduce the common mode current. Adjust the impedance between the conductive wire and ground. This improves the balance between the conductive lines and superimposes an ideal normal mode signal on the power line communication line to prevent the generation of radiation noise (see, for example, Patent Document 2).

  However, in the above-mentioned Patent Document 2, although related to the power line communication line, it is not possible to realize the exchange of power line communication (PLC) signals between the outlet 10 and the terminal device with respect to a conventional general power adapter. .

Japanese Patent Laid-Open No. 2006-100903 JP 2006-238370 A

  Therefore, in view of the above problems, the present invention is for passing a power communication line that enables a power line communication (PLC) signal to be exchanged between the outlet 10 and the terminal device with respect to a general power adapter. An object is to provide a power adapter.

  In order to solve the above problems, the present invention provides a power adapter for inserting an AC plug into an outlet and connecting a DC connector to a terminal device to supply DC power and passing a power communication signal. Is converted into a predetermined AC voltage, AC is converted into DC, AC component ripple is absorbed and connected to the DC connector, the side connected to the AC plug is a balanced type, and the side connected to the DC connector is An unbalanced power supply circuit, a plurality of capacitors connected to the AC plug side and connected to the DC connector side in parallel to the power supply circuit and a balanced-unbalanced transformer, and an alternating current It has a high-pass filter function that removes components and passes power communication signals from the AC plug to the DC connector, and conversely from the DC connector to the AC adapter. Characterized in that it comprises a bypass passage that provides a power adapter for passing the power communication line.

Furthermore, the detour has a high-pass filter function that removes an AC component of 50 Hz to 60 hz and passes a power communication signal in the range of 2 MHz to 30 MHz.
Further, a switch is provided for separating the detour and cutting off the power communication signal.

  As described above, according to the present invention, the AC plug is connected and converted to a predetermined AC voltage, the AC is converted to DC, the AC component ripple is absorbed and connected to the DC connector, and the AC plug is connected. A power supply circuit in which the side to be connected is a balanced type and the side connected to the DC connector is an unbalanced type, and a plurality of capacitors connected in parallel to the power supply circuit between the AC plug side and the DC connector side And a balanced-unbalanced transformer, and an AC component is removed, and a detour having a high-pass filter function for passing a power communication signal from the AC connector to the DC connector and conversely from the DC connector to the AC adapter is provided. Therefore, it becomes possible to transmit and receive a power communication signal between the outlet and the terminal device via the power adapter.

That is, two-way communication of power line communication signals is possible between terminal devices that require power supply with a power line and direct current, and charging mobile phones, notebook personal computers, etc. If transmission becomes possible, data on the mobile phone is edited with a notebook personal computer without special equipment such as a USB (Universal Serial Bus) cable or a wireless LAN (Local Area Network), and conversely, It is also possible to import data such as music and video into a mobile phone.
Since the detour is separated by a switch or the like, the power adapter is not limited to a single terminal device, and can be used in a plurality of general-purpose terminal devices. Some terminal devices are vulnerable to interference caused by power line communication signals such as radio. In such a case, the power line communication signal can be prevented from being transmitted to a terminal device that is vulnerable to interference.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a circuit diagram showing a schematic configuration of a power adapter for passing a power line communication signal according to the present invention. As shown in this figure, compared to FIG. 7, a bypass 26 is provided between the AC plug 21 and the DC connector 25 for the power supply circuit 32, and the bypass 26 is connected to the power line communication (PLC: Power Line Communication). ) Has a function to pass signals.

As described with reference to FIG. 7, the power supply circuit 32 includes the transformer 22, the rectifier circuit 23, and the smoothing circuit 24, and is the same as the circuit that converts alternating current into direct current and supplies direct current power to the terminal device.
The AC side of the power supply circuit 32 to which the AC plug 21 is connected is a balanced type, and the DC side of the power supply circuit 32 to which the DC connector 25 is connected is an unbalanced type.

The above is the main route for the original power supply, and DC power is supplied to the terminal device via this route.
The bypass circuit 26 is a high-pass filter parallel to the power supply circuit 32. For example, capacitors 28 and 29 are connected to the balanced lines branched from the balanced line between the AC plug 21 and the transformer 22, respectively. A balanced-unbalanced transformer (balun) 27 is connected to 28 and 29, and a capacitor 30 is connected between the signal line of the balanced-unbalanced transformer 27 and the DC connector 25, thereby enabling power line communication. The signal bypasses the power supply circuit 32.

The balanced-unbalanced transformer 27 converts a power line communication signal coming as a balanced signal into an unbalanced (single-ended) signal, and at the same time forms a high-pass filter with the capacitors 28, 29, 30.
The power line communication signal converted into unbalanced by the balanced-unbalanced transformer 27 of the bypass circuit 26 is combined with DC power immediately after the smoothing circuit 24, and then the cellular phone 11, the notebook personal computer 12, etc. from the DC connector 25. To the terminal device.

  The reverse transmission is also possible. That is, when a power line communication signal is placed on DC power from a terminal device that receives DC power supply, the power line communication signal is input from the DC connector 25 to the power adapter. The power line communication signal branches between the smoothing circuit 24 and the DC connector 25, is input to the bypass circuit 26, and is converted from the unbalanced signal to the balanced signal by the balanced-unbalanced transformer 27, and then the transformer 22 and the AC plug 21. Is combined into AC power.

FIG. 2 is a diagram showing the frequency characteristics of the bypass 26 of the power adapter in FIG. As shown in the figure, the bypass 26 is a high-pass filter, removes an AC component of 50 Hz to 60 Hz, and extracts a power line communication signal existing in a range of 2 MHz to 30 MHz.
Therefore, according to the present invention, it is possible to provide the bypass 26 for bidirectionally passing the power line communication signal in the power adapter, and transmitting / receiving the power communication signal between the outlet 10 and the terminal device via the power adapter. Can be performed.

  That is, two-way communication of power line communication signals is possible between terminal devices that require power supply with a power line and direct current, and a mobile phone 11 or a notebook personal computer 12 that is being charged can transmit information via the power line. If bi-directional transmission is possible, the data of the mobile phone 11 is edited by the notebook personal computer 12 without special equipment such as a USB (Universal Serial Bus) cable and a wireless LAN (Local Area Network), and on the contrary, the notebook Data such as music and video in the portable personal computer 12 can be taken into the mobile phone 11.

FIG. 3 is a circuit diagram showing a schematic configuration of a power adapter for passing a power line communication signal, which is a modification of FIG. As shown in this figure, compared with FIG. 1, a switch 31 is provided between the capacitor 30 and the DC connector 25, and the switch 31 cuts off the bypass circuit 26 and cuts off the power line communication signal.
This is because the power adapter is not limited to a single terminal device, and can be used in a plurality of general-purpose terminal devices. Some terminal devices are vulnerable to interference caused by power line communication signals such as radio. In such a case, it is also necessary to disconnect the detour 26 with the switch 31 or the like so that the power line communication signal is not transmitted to the terminal device that is vulnerable to interference.

It is a circuit diagram which shows schematic structure of the power adapter for letting a power line communication signal pass based on this invention. It is a figure which shows the frequency characteristic of the detour 26 of a power adapter in FIG. FIG. 5 is a circuit diagram showing a schematic configuration of a power adapter for passing a power line communication signal, which is a modification of FIG. 1. It is a figure which shows schematic shape of the power adapter used as the premise of this invention. When charging a mobile phone, it is a figure which shows the example of supply of the direct-current power by the power adapter of FIG. FIG. 5 is a diagram illustrating an example of the power adapter in FIG. 4 when supplying DC power to a notebook personal computer. It is a figure which shows the frequency characteristic of a PLC signal. It is a circuit diagram which shows schematic structure of the power adapter used as the premise of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Outlet 11 ... Mobile phone 12 ... Notebook-type personal computer 21 ... AC plug 22 ... Transformer 23 ... Rectifier circuit 24 ... Smoothing circuit 25 ... DC connector 26 ... Detour 27 ... Balance-unbalance transformer 28, 29, 30 ... Capacitor 31 ... Switch 32 ... Power supply circuit

Claims (3)

In a power adapter for inserting an AC plug into an outlet and connecting a DC connector to a terminal device to supply DC power and passing a power communication signal,
Connected to the AC plug, converts it to a predetermined AC voltage, converts AC to DC, absorbs ripples of AC components and is connected to a DC connector, the side connected to the AC plug is a balanced type, and the DC connector A power supply circuit in which the side connected to is unbalanced,
A plurality of capacitors connected in parallel to the power supply circuit and connected between the AC plug side and the DC connector side and a balanced-unbalanced transformer, an AC component is removed, and the AC plug is removed from the AC plug. A power adapter for passing a power communication line, comprising: a DC connector having a high-pass filter function for passing a power communication signal from the DC connector to the AC adapter. 2. The power adapter for passing a power communication line according to claim 1, wherein the detour has a high-pass filter function that removes an AC component of 50 Hz to 60 hz and passes a power communication signal in a range of 2 MHz to 30 MHz. The power adapter for passing a power communication line according to claim 1, further comprising a switch for separating the detour and blocking a power communication signal.

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