JP2008067366A - Power supply device and power line communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply device and a power line communication device capable of suppressing a peak value of a common mode current. <P>SOLUTION: A power connector 102 has a pair of transmission lines for making a connection to a power line for transmitting power. Power supplied from the power connector 102 is supplied via an impedance upper 291 to an AC/DC converter 301. The impedance upper 291 has a first inductance L1 in a first path P1 and a second inductance L2 which is different from the first inductance L1 in a second path P2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power supply device and a power line communication device.

  For example, in homes and the like, various electrical devices such as an information device such as a personal computer, a television monitor, a recording device, an image reproducing device, and an IP (Internet Protocol) telephone can communicate with each other via a predetermined communication network. There has been proposed a system that makes it possible to easily realize a linkage operation between a plurality of devices by connecting in a state. However, when performing data communication by wired communication in the home, etc., it is usually necessary to lay wiring such as cables and connectors used as transmission paths where necessary, so there are various cases when constructing a communication system. Construction may be required.

  On the other hand, in most cases, since a commercial power source, for example, AC 100V (50/60 Hz) is used in the home, power lines for supplying this power are already laid in every place in the home. Therefore, if these power lines can be used as a data communication transmission line, it is not necessary to newly provide a special communication line, and it is possible to secure a communication path simply by plugging a device used for communication into a commercial power outlet. become.

  Various techniques are known for power line communication technology (PLC: Power Line Communication) using such a power line for communication (for example, JP 2000-165304 A). At present, various manufacturers are conducting research and development in a predetermined frequency band (for example, 1.705 MHz to 30 MHz in the United States, 2 MHz to 30 MHz in Japan) in Japan and overseas. Specifically, it is assumed that a multicarrier signal is generated by using a plurality of subcarriers as in an OFDM (Orthogonal Frequency Division Multiplexing) method, and the multicarrier signal is transmitted through a power line.

  FIG. 28 is a diagram illustrating a current model on a transmission line such as a power line. A transmission line is comprised by the transmission line (C1, C2) which consists of a pair of conductor which is balanced with respect to the earth (earth).

  In FIG. 28, a pair of voltage sources (e10, e20) is provided at the left end of the transmission line. e10 and e20 have the same characteristics such as waveform, amplitude, and phase, and voltages generated from the voltage sources (e10, e20) (each voltage is assumed to be “e”) are applied to the lines (C1, C2). It is done.

  A load impedance (regular load) ZL is provided at the right end of the transmission line. In the transmission lines (C1, C2), differential (normal) mode currents (+ Id, -Id) flow in opposite directions.

  However, parasitic impedances (ground impedances) Z1 to Z3 are interposed between the transmission line and the ground (earth).

  Here, if the impedance values of the parasitic impedances Z2 and Z3 (this values are also expressed as Z2 and Z3) are not equal, the common mode current is a circulating current through the parasitic impedances (ground impedances) Z1 to Z3 and the ground. Ic flows.

  If the transmission line has a sufficiently high balance, it can be considered that Z2 = Z3, and the common mode current Ic does not flow. However, in a line with a relatively low balance, Z2 ≠ Z3, and the common mode current Ic flows.

  The amount of current of the common mode current Ic can be expressed as follows. In the following formula (1), e represents each voltage generated from each voltage source (e10, e20).

  Ic = e · (Z2−Z3) / (Z1 · Z2 + Z2 · Z3 + Z3 · Z1) (1)

  This common mode current Ic is bifurcated and flows equally to each of the pair of transmission lines (C1, C2). Therefore, a common mode current (current amount is Ic / 2) flows through each transmission line (C1, C2) in the same direction.

  When the common mode current Ic flows, it causes radiation from the line. That is, when signals of the same amplitude and opposite phase are superimposed on each of the pair of lines, the radiation component radiated from each line is canceled when the balanced state is maintained, but in the unbalanced state, There is a case that the radiation component is leaked outside without being completely canceled.

  If a line with high balance (for example, a line dedicated to communication such as an Ethernet (registered trademark) twisted pair cable) is used as the transmission line, the common mode current generated on the line is suppressed to a sufficiently low level. The problem does not occur.

  However, in a power line communication system in which a power line is used as a transmission line, since the balance of the power line is low, a common mode current generated on the transmission line is increased.

  In Japan, a frequency band of 2 to 30 MHz is expected to be approved for power line communication, but an allowable value for the quasi-peak value of the common mode current is scheduled. Therefore, there is a situation that the peak value of the common mode current in the frequency band used for power line communication needs to be suppressed to a predetermined allowable value or less.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a power supply device and a power line communication device capable of suppressing a peak value of a common mode current.

  The present invention provides a power line (900) that can be connected to a power line (900) having at least two transmission lines to transmit power, and the power line via the power line connection part (400). A power supply unit (300) that receives the power supply, and an inductor unit (290: 291) provided between the power line connection unit (400) and the power supply unit (300), the inductor unit (290; 291) includes a first inductance (L1), a first path (P1) connected to one of the transmission lines, and a second inductance different from the first inductance (L1). A power supply device is provided that includes (L2) and a second path (P2) connected to a transmission line different from the transmission line connected to the first path (P1).

  With this configuration, for example, when the power supply device is connected to a single-phase power supply, the inductance in the two paths between the power supply connection unit and the power supply unit becomes unbalanced, so that the plugging direction of the outlet connected to the power line is The difference in the common mode current value due to can be suppressed, and the peak value of the common mode current can be suppressed.

  A second aspect of the present invention is the power supply device according to the first aspect, wherein the inductor section (290: 291) includes the first inductance (L1) provided in the first path (P1). And a second inductor (11b) having the second inductance (L2) provided in the second path (P2) is provided. Is.

  With this configuration, since the inductor is inserted separately in each path, the degree of freedom of the mounting position is high, and the inductance value can be easily adjusted.

  The third aspect of the present invention is the power supply device according to the second aspect, wherein the first inductor (for example, 11a) includes a third inductor (11a1) having a predetermined inductance and a fourth inductor ( 11a2) is provided.

  With this configuration, the third inductor and the fourth inductor are provided in the first path, and the inductances of the two paths are unbalanced. Therefore, the inductance can be easily and finely adjusted, and the balance in the power supply unit can be adjusted. The degree can be improved.

  Fourthly, the present invention provides the power supply device according to the first aspect, wherein the inductor section (290; 291) includes a first coil section (12a) provided in the first path (P1). And a common mode choke coil (12) inserted in the second path (P2) and having a second coil part (12b) having a different number of turns from the first coil part (12a). An apparatus is provided.

  With this configuration, the inductance of the two paths can be unbalanced with a single component having only the common mode choke coil, so that variations in the power supply device can be suppressed.

  The fifth aspect of the present invention is the power supply device according to the first aspect, wherein the inductor section (290; 291) is provided in each of the first path (P1) and the second path (P2). A common mode choke coil (13a) having a coil portion having the same number of turns, and an inductor provided on one of the first path (P1) and the second path (P2). A power supply apparatus is provided.

  This configuration unbalances the inductance of the two paths using an inductor in addition to the common mode choke coil, so that the inductance value can be easily and finely adjusted, thereby improving the balance in the power supply unit. be able to.

  Sixthly, in the power supply device according to any one of the first to fifth aspects, the inductor unit (290; 291) attenuates a signal in a frequency band excluding at least an AC power supply frequency. A power supply device having characteristics is provided.

  With this configuration, the inductor unit can block unnecessary frequency band signals even when the power supply device is connected to a power line communication system that performs communication in a high frequency band using a power line.

  Seventhly, the present invention provides the power supply device according to any one of the first to sixth aspects, wherein the fuse (282) connected to the power line connecting portion (400) and the inductor portion (290; 291). And a second common mode choke coil (21a) connected between the fuse and the first surge absorbing element (281). A power supply is provided.

  With this configuration, it is possible to reduce the common mode current in the common mode choke coil while protecting the circuit on the side opposite to the power line connecting portion in the first surge absorbing element against the surge.

  Eighthly, according to the present invention, there is provided the power supply apparatus according to the seventh aspect, wherein the second common mode choke coil (21a) has a self-resonant frequency of 20 megahertz or more. is there.

  In the short wave band, the common mode current tends to increase as the frequency increases, but the common mode choke coil reduces the common mode current on the higher frequency side as the self-resonant frequency is higher. Therefore, with this configuration, even when the power supply device is used in a short-wave power line communication system, the high-frequency side common mode current is reduced by using the second common mode choke coil having a self-resonance frequency of 20 megahertz or more. Can be reduced.

  Ninthly, the power supply device according to the seventh or eighth aspect is provided between the fuse (282) and the second common mode choke coil (21a). There is provided a power supply device further comprising a second surge absorbing element (22) having a capacity smaller than that of the surge absorbing element (281).

  With this configuration, it is possible to protect the second common mode choke coil against surge in the second surge absorbing element while reducing the common mode current.

  The tenth aspect of the present invention is the power supply device according to any one of the first to ninth aspects, wherein the power connection portion (400) is formed by twisting at least two wires connected to each of the transmission lines. There is provided a power supply device including the power supply cable (601).

  With this configuration, the balance is improved by the power cable in the stranded state, so that the common mode current can be reduced.

  In the eleventh aspect of the present invention, there is provided a power line communication apparatus (100) including the power supply apparatus described in any one of the first to tenth aspects.

  With this configuration, it is possible to provide a power line communication device that suppresses the peak value of the common mode current.

  The twelfth aspect of the present invention is the power line communication device (100) according to the eleventh aspect, wherein the transmission unit (1) outputs a transmission signal to be transmitted through the power line (900), and the transmission unit ( 1) The secondary winding connected to 1) and the branch part between the power line connection part (400) and the inductor part (290; 291) are connected to superimpose the transmission signal on the power line (900). A coupler transformer (271) having a primary winding, and a capacitor section connected to the primary winding of the coupler transformer (271) and having a higher impedance in the frequency band of the AC voltage depending on the frequency band of the transmission signal. 272a, 272b), and a third common mode choke coil (31) connected between the capacitor units (272a, 272b) and the transmitter unit (1). In which the communication device is provided.

  With this configuration, since the common mode choke coil is arranged in the signal system, even when the power supply device handles a large current, the common mode choke coil having a large common mode impedance is used without increasing the size of the common mode choke coil. And common mode current can be reduced.

  Thirteenth, in the power line communication device (100) according to the twelfth aspect, the third common mode choke coil (31) includes the capacitor unit and a primary winding of the coupler transformer. A power line communication device connected between the two is provided.

  With this configuration, the common mode choke coil can be arranged in the signal system.

  The fourteenth aspect of the present invention is the power line communication device (100) according to the twelfth aspect, wherein the third common mode choke coil (21) includes the transmitter and the coupler transformer (271). A power line communication device connected between the next winding is provided.

  With this configuration, the common mode choke coil can be arranged in the signal system.

  According to a fifteenth aspect of the present invention, there is provided the power supply device according to the first aspect, wherein a ratio of the second inductance to the first inductance is 1.21-2. It is.

  With this configuration, it is possible to reduce the common mode current level difference due to the suppression of the common mode current and the outlet insertion direction.

  Sixteenth, the power supply device according to the fifteenth aspect, wherein a power supply device in which a ratio of the second inductance to the first inductance is 1.3 to 2 is provided. It is.

  With this configuration, it is possible to reduce the common mode current level difference due to the suppression of the common mode current and the outlet insertion direction.

  ADVANTAGE OF THE INVENTION According to this invention, the power supply device and power line communication apparatus which can suppress the peak value of a common mode electric current can be provided.

  Hereinafter, a communication device according to an embodiment of the present invention will be described with reference to the drawings. As an example of the communication apparatus, a description will be given by taking as an example a communication apparatus that uses a power line as a transmission path and performs broadband communication (2 to 30 MHz) of a multicarrier communication system.

  First, an outline of the communication device will be described. As an example of the communication apparatus, a PLC (Power Line Communication) modem, which is one of power line communication apparatuses, will be described.

  The communication apparatus 100 shown in FIGS. 1 to 3 has a housing 101, and LEDs (Light Emitting Diodes) 104a, 104b, and 104c are arranged on the front surface of the housing 101 as shown in FIGS. A display unit 104 having the above is provided. Further, as shown in FIG. 3, a power connector 102 and a LAN (Local Area Network) modular jack 103 such as an RJ45 are provided on the rear surface of the housing 101.

  The power connector 102 is connected to a power cable 600 (see FIG. 4) such as a parallel cable (for example, a VVF cable). A LAN cable (not shown) is connected to the modular jack 103.

  As illustrated in FIG. 4, the communication device 100 includes a circuit module 200, a switching power supply 300, and an AC / DC conversion unit 301.

  The switching power supply 300 supplies various (for example, +1.2 V, +3.3 V, +12 V) voltages to the circuit module 200, and includes, for example, a line filter, a switching transformer, and a DC-DC converter (all illustrated). Z)). The AC / DC conversion unit 301 converts AC power supplied from the power line 900 via the power connector 102 into DC and supplies it to the switching power supply 300. Note that the switching power supply 300 and the AC / DC conversion unit 301 function as an example of a power supply unit that receives power supplied from the power line 900.

  The circuit module 200 includes a main IC (Integrated Circuit) 210, an AFE IC (Analog Front End IC) 220, an Ethernet (registered trademark) PHY IC (Physical Layer Integrated Circuit) 230, a memory 240, a low-pass filter (LPF) 251. , Driver IC 252, band pass filter (BPF) 260, coupler 270, surge absorber 281, fuse 282, and impedance upper 290 are provided.

  The main IC 210 includes a CPU (Central Processing Unit) 211, a PLC / MAC (Power Line Communication Media Access Control layer) block 212, and a PLC / PHY (Power Line Communication Physical layer) block 213. The CPU 211 is equipped with a 32-bit RISC (Reduced Instruction Set Computer) processor. The PLC / MAC block 212 manages the MAC layer (Media Access Control layer) of the transmission signal, and the PLC / PHY block 213 manages the PHY layer (Physical layer) of the transmission signal.

The AFE / IC 220 includes a D / A converter (DAC: D / A Converter) 221, an A / D converter (ADC: A / D Converter) 222, and a variable amplifier (VGA).
) 223 and 224.

  The coupler 270 and the impedance upper 290 are connected to the power connector 102 via the surge absorber 281 and the fuse 282, and further connected to the power line 900 via the power cable 600, the power plug 400, and the outlet 500.

  The surge absorber 281 functions as an example of a first surge absorbing element, and protects a circuit connected to the opposite side of the power connector 102 across the surge absorber 281 from a surge input from the power line 900 side. . In the present embodiment, the surge absorber 281 has a capacitance value of 50 [pF] or more.

  The impedance upper 290 has a characteristic of attenuating at least a signal in a frequency band excluding the AC power supply frequency, and can cut off a signal of a high-frequency component unnecessary as a power supply from the signal supplied to the AC / DC conversion unit 301, for example. .

  The power line 900 has at least two transmission lines to transmit power. In the present embodiment, a power line that transmits single-phase AC power having a pair of transmission lines will be described as an example. The power connector 102 or the power connector, the power cable 600, and the power plug 400 function as an example of a power line connection unit that can be connected to the power line 600.

  The coupler 270 includes a coil transformer 271 and coupling capacitors 272a and 272b.

  The CPU 211 uses the data and control program stored in the memory 90 to control the operation of the PLC / MAC block 212 and the PLC / PHY block 213, and also controls the communication device 100 as a whole.

  The communication device 100 performs multi-carrier communication using a plurality of subcarriers such as an OFDM (Orthogonal Frequency Division Multiplexing) method, and digital signal processing for performing such transmission is performed by the main IC 210, particularly the PLC · This is performed in the PHY block 213.

  Here, the PLC / PHY block 213, the DAC 221, the VGA 223, the LPF 251, and the driver IC 252 operate as the transmission unit 1. The PLC / PHY block 213, the ADC 12, the VGA 224, and the BPF 261 function as the receiving unit 2.

  In the above description, the modem is shown as an example of the power line communication device. However, the present invention is not particularly limited thereto, and may be an electric device (for example, a home appliance such as a television) provided with the modem.

(First embodiment)
FIG. 5 is a diagram illustrating the impedance upper of the communication apparatus according to the first embodiment, and the same reference numerals are given to portions overlapping with FIG. 4. As shown in FIG. 5, the power connector 102 is connected to the branch portion 299 by a pair of electric wires. Between the power connector 102 and the branch portion 299, a fuse 282 is inserted into one electric wire, and a surge absorber 281 is inserted between the pair of electric wires. Each of the pair of electric wires branches in two directions at a branching portion 299, one is connected to the coupler 270, and the other is connected to the AC / DC converting portion 301 via the impedance upper 291. The configuration ahead of the coupler 270 and the AC / DC converter 301 as viewed from the branching unit 299 is the same as that in FIG.

  Similar to the impedance upper 290 described with reference to FIG. 4, the impedance upper 291 has a characteristic of attenuating a signal in a frequency band excluding at least the AC power supply frequency. However, the impedance upper 291 has a first inductance L1, has a first path P1 connected to one of the transmission lines of the power line 600, and a second inductance L2, and is connected to one of the transmission lines of the power line 600. And a second path P2 to be connected. The first inductance L1 and the second inductance L2 are different values. That is, the impedance upper 291 has an unbalanced inductance. The impedance upper 291 functions as an example of an inductor provided between the power connector 102 and the AC / DC converter 301. In the following description, inductance refers to an induction coefficient, and inductor refers to a circuit element having a predetermined inductance.

  FIG. 6 is a diagram showing frequency-common mode current characteristics when an impedance upper having a balanced inductance (100 [μH] inductance for each path) is used. The two characteristics shown in FIG. 6 are the characteristics when the insertion direction of the power plug 400 into the outlet 500 is changed. That is, as apparent from FIG. 6, a difference occurs in the common mode current depending on the direction in which the outlet plug is inserted.

  Since the signal of the power line communication device is a differential signal, in order to improve the balance of the device itself, it is designed so that the balance is improved by using the same wiring pattern and component constant. However, it is difficult to make the component arrangement and wiring pattern completely bilaterally symmetric, resulting in some unbalance.

  Therefore, the communication device according to the present embodiment intentionally destroys the balance of the inductance of the impedance upper 291 to change the LCL (Longitudinal Conversion Loss) in a specific frequency range, and is generated depending on the direction in which the outlet plug is inserted. The common mode current difference is reduced and the peak value of the common mode current is suppressed.

  7 to 8 are diagrams showing frequency-common mode current (CMI) characteristics when an impedance upper having an unbalanced inductance is used. 7 shows the case where the inductance L1 = 100 [μH] and the inductance L2 = 122 [μH], and FIG. 8 shows the outlet of the power plug 400 when the inductance L1 = 100 [μH] and the inductance L2 = 147 [μH]. Each characteristic when the insertion direction to 500 is changed is shown.

  As shown in FIGS. 7 to 8, the impedance upper 291 has an unbalanced inductance, thereby reducing the level difference of the common mode current due to the outlet insertion direction and reducing the peak value of the common mode current. I understand.

  Next, a specific configuration example of the impedance upper 291 of the present embodiment will be described. FIG. 9 is a diagram illustrating a first example of a specific configuration of the impedance upper. As shown in FIG. 9, the impedance upper 291 includes an inductor 11a provided in the first path P1 and an inductor 11b provided in the second path P2. The inductor 11a functions as an example of a first inductor and has a first inductance L1. The inductor 11b functions as an example of a second inductor and has a second inductance L2.

  Thereby, since the inductors 11a and 11b are separately provided in each path, the degree of freedom of mounting positions of the inductors 11a and 11b is high, and the inductance value can be easily adjusted.

  FIG. 10 is a diagram illustrating a second example of a specific configuration of the impedance upper. As shown in FIG. 10, the impedance upper 291 includes an inductor 11a1 and an inductor 11a2 provided in the first path P1, and an inductor 11b provided in the second path P2. The inductor 11a1 functions as an example of a third inductor and has, for example, a second inductance L2. The inductor 11a2 functions as an example of a fourth inductor, and has an inductance whose combined inductance with the inductor 11a1 is the first inductance L1. The inductor 11b functions as an example of a second inductor and has a second inductance L2.

  For example, when the first inductance L1 is 122 [μH] and the second inductance L2 is 100 [μH], the inductance of the inductor 11a1 is 100 [μH], the inductance of the inductor 11a2 is 22 [μH], and the inductor 11b The inductance is 100 [μH].

  That is, the inductor 11a1 and the inductor 11b have the same inductance. The inductance unbalance amount between the paths of the impedance upper 291 is adjusted by the inductor 11b. As a result, the inductance values of the first path and the second path can be easily and finely adjusted, so that the balance in the AC / DC conversion unit 302 can be improved.

  Note that the inductance of the inductor 11a1 does not have to be the second inductance L2, and the inductor 11a1 and the inductor 11a2 may be configured so that the combined inductance is L1.

  FIG. 11 is a diagram illustrating a third example of a specific configuration of the impedance upper. As shown in FIG. 11, the impedance upper 291 includes a common mode choke coil 12. The common mode choke coil 12 includes a first coil part 12a provided in the first path P1 and a second coil part provided in the second path P2 and having a different number of turns from the first coil part 12a. 12b. In this way, the impedance upper 291 can have an inductance-unbalanced characteristic in which the first path P1 has the first inductance L1 and the second path P2 has the second inductance L2.

  Thereby, in the impedance upper 291, the inductance of the two paths can be unbalanced with one component of only the common mode choke coil 12, so that variations between devices can be suppressed.

  FIG. 12 is a diagram illustrating a fourth example of a specific configuration of the impedance upper. As shown in FIG. 12, the impedance upper 291 includes a common mode choke coil 13a inserted in each of the first path P1 and the second path P2 and having the same number of turns, and the first path And an inductor 13b provided in one of P1 and the second path P2 (first path P1 in FIG. 12).

  The impedance upper 291 is in a state where the inductance is balanced in the first path P1 and the second path P2 in the common mode choke coil 13a, but is unbalanced by the inductor 13b provided in one path. It will have the characteristic.

  As a result, the inductance values of the first path and the second path can be easily and finely adjusted, so that the balance in the AC / DC conversion unit 302 can be improved.

  In this way, in the portion corresponding to the power supply device (for example, the portion from the power plug 500 to the switching power supply 300 via the branching portion 299), the inductances in the two paths for transmitting power become unbalanced, and thus the power line The difference in the common mode current value due to the plugging direction of the outlet connected to the can be suppressed, and the peak value of the common mode current can be suppressed.

  Next, frequency-common mode current characteristics when an impedance upper having a balanced inductance is used will be described with reference to examples other than FIG.

  FIG. 29 is a diagram showing frequency-common mode current characteristics when an impedance upper having a balanced inductance (inductance of 220 [μH] for each path) is used, and FIG. 30 is balanced. It is a figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an inductance (Inductance of 330 [microH] about each path | route). The range of the frequency at which the common mode current was measured is 2 to 30 MHz, the same as in the case of FIG. The two characteristics shown in FIGS. 29 and 30 are the characteristics when the insertion direction of the power plug 400 into the outlet 500 is changed. As apparent from FIGS. 29 and 30, a difference occurs in the common mode current depending on the direction in which the outlet plug is inserted. Therefore, it can be understood that the same tendency as in FIG. 6 is shown.

  The measurement results of FIGS. 6, 29, and 30 are shown in Table 1 below.

  In Table 1, the maximum CMI value is the maximum common mode current value obtained in each measurement. The first average CMI value is an average value of the common mode current measured in the range of 2 to 30 MHz in the case of the first insertion direction. The second average CMI value is an average value of the common mode current measured in the range of 2 to 30 MHz in the case of the second insertion direction. ΔCMI is a difference (absolute value) between the first average CMI value and the second average CMI value. As the value of ΔCMI is lower, the level difference of the common mode current due to the outlet insertion direction becomes smaller and the balance of the power supply device is improved.

  Next, examples other than FIGS. 7 and 8 will be described with respect to frequency-common mode current characteristics when an impedance upper having an unbalanced inductance is used.

  FIGS. 31 to 42 are diagrams showing frequency-common mode current (CMI) characteristics when an impedance upper having an unbalanced inductance is used. 31 shows an inductance L1 = 100 [μH], an inductance L2 = 133 [μH], FIG. 32 shows an inductance L1 = 100 [μH], an inductance L2 = 168 [μH], and FIG. 33 shows an inductance L1. = 100 [μH], inductance L2 = 200 [μH], FIG. 34 shows an inductance L1 = 220 [μH], and inductance L2 = 267 [μH], FIG. 35 shows an inductance L1 = 220 [μH], In the case of the inductance L2 = 288 [μH], FIG. 36 shows the inductance L1 = 220 [μH], and in the case of the inductance L2 = 320 [μH], FIG. 37 shows the inductance L1 = 220 [μH] and the inductance L2 = 370 [μH]. ], In FIG. 38, inductance L1 = 220 [μH], inductance In the case of 2 = 440 [μH], FIG. 39 shows an inductance L1 = 330 [μH], and in the case of an inductance L2 = 398 [μH], FIG. 40 shows an inductance L1 = 330 [μH] and an inductance L2 = 430 [μH]. 41 shows a case where the inductance L1 = 330 [μH] and the inductance L2 = 480 [μH], and FIG. 42 shows a case where the inductance L1 = 330 [μH] and the inductance L2 = 550 [μH]. Each characteristic when the insertion direction into the outlet 400 of 400 is changed is shown.

  The measurement results of FIGS. 31 to 42 are shown in Table 2 below.

  In Table 2, the definition of the maximum CMI value and the like is the same as in Table 1. L2 / L1 is a ratio between the second inductance and the first inductance. Resonance is a common mode current that greatly exceeds the regulatory value. Table 2 shows the presence or absence of resonance confirmed in each measurement.

  43 to 45 are diagrams showing the relationship between L2 / L1 and ΔCMI. 43 shows a case where L1 = 100 μH, FIG. 44 shows a case where L1 = 220 μH, and FIG. 45 shows a case where L1 = 330 μH. 43 to 45, the broken line indicates the value of ΔCMI when L2 / L1 = 1.

  As apparent from FIGS. 31 to 45 and Table 2, the impedance upper 291 has an unbalanced inductance, so that the level of the common mode current depending on the outlet plugging direction in the range of L2 / L1 of 1.2 to 2. It can be seen that as the difference becomes smaller, the peak value of the common mode current tends to decrease. Specifically, the maximum CMI value can be confirmed to be reduced by about 2% to 7% with two exceptions. The first average CMI value can be confirmed to be reduced by approximately 1% to 11% with one exception. Moreover, the value of ΔCMI can be confirmed to be reduced by 4% to 83% without exception. 43 to 45, it can be confirmed that ΔCMI is lower than the broken line even when L2 / L1 is 1.2 or less. However, when L2 / L1 is 1.2 or less, the common mode current greatly exceeds the legal regulation value. Therefore, the ratio between the first inductance and the second inductance is not appropriate.

(Second Embodiment)
FIG. 13 is a configuration diagram illustrating a part of the communication apparatus according to the second embodiment. In FIG. 13, the same reference numerals are given to the portions overlapping with FIG. 5 described in the first embodiment.

  As shown in FIG. 13, the communication device includes a common mode choke coil 21 a that is connected between a surge absorber 281 and a fuse 282 and functions as an example of a second common mode choke coil.

  FIG. 14 is a diagram illustrating frequency-common mode current characteristics of the communication device according to the second embodiment. In FIG. 14, a characteristic C200 is a characteristic when the common mode choke coil 21a as shown in FIG. 13 is not inserted, and a characteristic C201 is a case where the common mode choke coil 21a as shown in FIG. 13 is connected. It is a characteristic.

  As shown in FIG. 14, it can be seen that the common mode choke coil 21 a is connected, so that the common mode current is reduced particularly in a high band of 15 [MHz] or higher.

  Next, the characteristics of the common mode current depending on the position where the common mode choke coil is connected will be described using a comparative example.

  FIG. 15 is a configuration diagram illustrating a part of a comparative example of the communication apparatus according to the second embodiment. As shown in FIG. 15, the common mode choke coil 21 b is connected to the subsequent stage of the surge absorber 281 when viewed from the power connector 102.

  FIG. 16 is a diagram illustrating frequency-common mode current characteristics of a comparative example of the communication device according to the second embodiment. In FIG. 16, a characteristic C200 is the same as the characteristic C200 in FIG. 14, and a characteristic C202 is a characteristic when the common mode choke coil 21b as shown in FIG. 15 is connected.

  As shown in FIG. 16, when the common mode choke coil 21b is connected, the common mode current is reduced particularly in a high band of 15 [MHz] or more, as in the case where the common mode choke coil 21a is connected. I understand that.

  Here, comparing the characteristic C201 shown in FIG. 14 with the characteristic C202 shown in FIG. 16, the characteristic C201 has a reduced common mode current than the characteristic C202. That is, it can be seen that the common mode choke coil can reduce the common mode current when it is provided at the front stage rather than the rear stage of the surge absorber 281 when viewed from the power connector 102.

  Since the common mode choke coil 21a is relatively resistant to surges, in the present embodiment, by providing the common mode choke coil 21a in the previous stage when viewed from the power connector 102, it is possible to obtain a high effect on reducing the common mode current. .

  Next, the common mode current characteristics depending on the number of turns of the common mode choke coil will be described.

  FIG. 17 is a diagram illustrating frequency-impedance characteristics according to the number of turns of the common mode choke coil. In FIG. 17, characteristics C211 to C215 indicate the frequency-impedance characteristics of the common mode choke coils having different numbers of turns, and the characteristics C211, C212, C213, C214, The characteristic C215 is shown.

  As shown in FIG. 17, the impedance of the common mode choke coil increases as the number of turns increases. It can also be seen that as the number of turns increases, the frequency at which the impedance value peaks is lowered, that is, the self-resonant frequency, which is a frequency that changes from inductive to capacitive, is lowered.

  18A and 18B are diagrams showing frequency-common mode current characteristics according to the number of turns of the common mode choke coil. FIG. 18A shows a characteristic C221, FIG. 18B shows a characteristic C222, and FIG. Shows the characteristic C223, and FIG. 18D shows the characteristic C224. Characteristics C221 to C224 indicate frequency-common mode current characteristics when the common mode choke coil 21a having different winding numbers is used. The characteristics C221, the characteristics C222, the characteristics C223, and the characteristics C224 are shown in order from the smallest number of turns of the common mode choke coil 21a. Note that the number of turns of the common mode choke coil showing the characteristics C221 to C224 is the same as the number of turns of the common mode choke coil showing the characteristics C211 to C214.

  As shown in FIG. 18, when the number of turns of the common mode choke coil is large, the common mode current tends to be small on the low frequency side and large on the high frequency side. On the other hand, when the number of turns of the common mode choke coil is small, the common mode current tends to be large on the low frequency side and small on the high frequency side.

  Here, as shown in FIG. 18, the common mode current does not depend on the number of turns and tends to increase as the frequency increases as a whole. Therefore, in order to suppress the peak value of the common mode current, it is necessary to reduce the common mode current on the high frequency side. Therefore, a common mode choke coil having a small number of turns, that is, a common mode choke coil having a high self-resonance frequency (preferably having a self-resonance frequency of 20 [MHz] or higher) as described with reference to FIG. preferable.

  FIG. 19 is a configuration diagram illustrating a part of a modification of the communication device according to the second embodiment. Portions overlapping those in FIG. 13 are denoted by the same reference numerals. As shown in FIG. 19, the communication device of this modification includes a surge absorber 22 provided between a common mode choke coil 21a and a fuse 282 and functioning as an example of a second surge absorbing element.

  The surge absorber 22 can protect the common mode choke coil 21a against surge while reducing the common mode current.

  The surge absorber 22 is preferably a glass tube type surge absorber that is at least smaller than the capacitance value of the surge absorber 281, for example, a small capacitance value of about 10 [pF]. Thereby, it is possible to reduce the influence of the common mode choke coil 21a on the effect of reducing the common mode current when the common mode choke coil 21a is installed in front of the surge absorber 281 when viewed from the power connector 102. In the example shown in FIG. 19, a capacitor may be used instead of the surge absorber 281.

  In the description of the second embodiment, the case where the impedance upper 290 having a balanced inductance characteristic is used as the impedance upper has been described. However, the impedance upper has the unbalanced inductance described in the first embodiment. An impedance upper 291 may be used.

  FIG. 20 is a diagram illustrating frequency-common mode current characteristics when an impedance upper having an unbalanced inductance is used in the communication device according to the second embodiment. In FIG. 20, a characteristic C231 is a characteristic when the impedance upper 291 as shown in FIG. 5 is connected and the common mode choke coil 21a is not connected. A characteristic C232 is a substitute for the impedance upper 290 in FIG. This is a characteristic when the impedance upper 291 is connected to.

  As shown in FIG. 20, it can be seen that the common mode current is reduced by connecting the common mode choke coil 21a. Therefore, by using the impedance upper 291 having an unbalanced inductance, in addition to the effect of reducing the level difference of the common mode current due to the plug-in direction of the power plug and the suppression of the peak value of the common mode current, the common mode Current can be suppressed.

  According to the second embodiment, the common mode choke between the surge absorber 281 and the fuse 282 in a portion corresponding to the power supply device (for example, a portion from the power plug 500 to the switching power supply 300 via the branch portion 299). By connecting the coil 21a, it is possible to reduce the common mode current in the common mode choke coil 21a while protecting the circuit on the opposite side of the power line connecting portion in the surge absorber 281 from the surge.

(Third embodiment)
FIG. 21 is a configuration diagram illustrating a part of the first example of the communication apparatus according to the third embodiment, and FIG. 22 is a configuration illustrating a part of the second example of the communication apparatus according to the third embodiment. FIG. 21 and 22, the same reference numerals are given to the portions overlapping with FIG. 4 or FIG. 5.

  As shown in FIG. 21, the communication device of the first example includes a common mode choke coil 31 that is connected between coupling capacitors 272a and 272b and a coupler transformer 271 and functions as a third common mode choke coil. It is to be prepared.

  Specifically, the coupler transformer 271 has a primary winding 271a and a secondary winding 271b. The secondary winding 271b is connected to the transmission unit 1 that outputs a transmission signal. Further, the primary winding 271a is connected to the branch portion and superimposes the transmission signal on the power line 900.

  Coupling capacitors 272a and 272b are connected to primary winding 271a of coupler transformer 271 and function as an example of a capacitor unit having a higher impedance in the frequency band of the AC voltage depending on the frequency band of the transmission signal. The coupling capacitors 272a and 272b separate the high frequency power line communication signal from the signal flowing through the power line 900.

  As shown in FIG. 22, the communication device of the second example is connected between the transmission unit 1 and the secondary winding 271b of the coupler transformer 271 and functions as a third common mode choke coil. A choke coil 31 is provided.

  FIG. 23 is a diagram illustrating frequency-common mode current characteristics of the communication device according to the third embodiment. 23, a characteristic C301 is a characteristic when the impedance upper 290 as shown in FIG. 4 is connected and the common mode choke coil 31 or 32 is not connected. A characteristic C302 is shown in FIGS. This is a characteristic when the common mode choke coil 31 or 32 is connected.

  As shown in FIG. 23, it can be seen that the common mode choke coil 31 or 32 is connected, so that the common mode current is reduced particularly in a high region of 15 [MHz] or higher.

  When the power supply of the communication device needs to handle a large current, a large current needs to flow through the power supply system extending from the power connector 102 to the switching power supply 300 via the branch portion 299. In order to reduce the common mode current by inserting the common mode choke coil into such a power supply system, it is necessary to enlarge the common mode choke coil. Therefore, it is difficult to use a common mode choke coil having a sufficient common mode impedance.

  Therefore, in the communication apparatus according to the third embodiment, as shown in FIGS. 21 and 22, the common mode choke coils 31 and 32 are branched from coupling capacitors 272a and 272b in which signals in the frequency band of the AC voltage are cut off. It is arranged in the signal system on the rear stage as viewed from the unit 299. Therefore, even when the power supply device handles a large current, a common mode choke coil having a large common mode impedance can be used without increasing the size of the common mode choke coil, and the common mode current can be further reduced. .

  In the description of the third embodiment, the case where the impedance upper 290 having a balanced inductance characteristic is used as the impedance upper has been described. However, the impedance upper has the unbalanced inductance described in the first embodiment. An impedance upper 291 may be used.

  FIG. 24 is a diagram illustrating frequency-common mode current characteristics when an impedance upper having an unbalanced inductance is used in the communication apparatus according to the third embodiment. 24, the characteristic C231 is a characteristic when the impedance upper 291 as shown in FIG. 5 is connected and the common mode choke coil 31 or 32 is not connected. The characteristic C312 is the impedance in FIG. This is a characteristic when an impedance upper 291 is connected instead of the upper 290.

  As shown in FIG. 24, it can be seen that the common mode choke coil 31 or 32 is connected to reduce the common mode current. Therefore, by using the impedance upper 291 having an unbalanced inductance, in addition to the effect of reducing the level difference of the common mode current due to the plug-in direction of the power plug and the suppression of the peak value of the common mode current, the common mode Current can be suppressed.

  According to the third embodiment of the present invention, the common mode current can be reduced even in the power line communication device in which the power source handles a large current.

(Fourth embodiment)
FIG. 25 is an explanatory diagram showing a power cable according to the fourth embodiment. As shown in FIG. 25, the power cable 601 has a pair of electric wires 41 and 42 connected to each of the transmission lines of the power line 900. And these electric wires 41 and 42 are twisted. Thereby, the balance in the power cable 601 is improved, and the common mode current can be reduced.

  FIG. 26 is a diagram illustrating frequency-common mode current characteristics when the power cable according to the fourth embodiment of the present invention is used in the communication device according to the second embodiment. In FIG. 26, a characteristic C401 is a characteristic when the power cable 600 which is a parallel cable is connected to the communication apparatus shown in FIG. 13, and a characteristic C402 is a characteristic where the power cable 601 is connected to the communication apparatus shown in FIG. The case characteristics. As shown in FIG. 26, it can be seen that the common mode current is reduced by connecting the power cable 601 in the form of a stranded wire to the power connector 102.

  FIG. 27 is a diagram illustrating frequency-common mode current characteristics when the impedance upper having an unbalanced inductance and the power cable according to the fourth embodiment are used in the communication device according to the second embodiment. In FIG. 27, a characteristic C232 is a characteristic when the power cable 600 that is a parallel cable is connected to a communication apparatus to which the impedance upper 291 is connected instead of the impedance upper 290 in FIG. This is a characteristic when a stranded wire-shaped power cable 601 is connected to a communication device to which an impedance upper 291 is connected instead of the upper 290.

  As shown in FIG. 27, it can be seen that the common mode current is reduced by connecting the stranded wire-shaped power cable 601. Therefore, by using the impedance upper 291 having an unbalanced inductance, in addition to the effect of reducing the level difference of the common mode current due to the plug-in direction of the power plug and the suppression of the peak value of the common mode current, the common mode Current can be suppressed.

  According to such 4th Embodiment, a power supply cable which has a strand-shaped electric wire is used, A balance degree improves and it can reduce a common mode electric current.

  INDUSTRIAL APPLICABILITY The power supply device and the power line communication device of the present invention have an effect capable of suppressing the peak value of the common mode current, and are useful for a power line communication system using a short wave band.

1 is an external perspective view of a communication device according to an embodiment of the present invention. The front view of the communication apparatus which concerns on embodiment of this invention The rear view of the communication apparatus which concerns on embodiment of this invention The block diagram which shows an example of the basic hardware constitutions of the communication apparatus which concerns on embodiment of this invention Explanatory drawing which shows the impedance upper part of the communication apparatus which concerns on the 1st Embodiment of this invention. The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has the inductance (L1 = L2 = 100microH) which is balanced. The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 100 (micro | micron | mu) H, L2 = 122 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 100 (micro | micron | mu) H, L2 = 147 (micro | micron | mu) H). The figure which shows the 1st example of a specific structure of the impedance upper part of the communication apparatus which concerns on the 1st Embodiment of this invention. The figure which shows the 2nd example of a specific structure of the impedance upper part of the communication apparatus which concerns on the 1st Embodiment of this invention. The figure which shows the 3rd example of a specific structure of the impedance upper part of the communication apparatus which concerns on the 1st Embodiment of this invention. The figure which shows the 4th example of a specific structure of the impedance upper part of the communication apparatus which concerns on the 1st Embodiment of this invention. The block diagram which shows a part of communication apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows the frequency-common mode current characteristic of the communication apparatus which concerns on the 2nd Embodiment of this invention. The block diagram which shows a part of comparative example of the communication apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows the frequency-common mode current characteristic of the comparative example of the communication apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows the frequency-impedance characteristic according to the number of turns of the common mode choke coil Diagram showing frequency vs. common mode current characteristics for each number of turns of common mode choke coil The block diagram which shows a part of modification of the communication apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance for the communication apparatus which concerns on the 2nd Embodiment of this invention. The block diagram which shows a part of 1st example of the communication apparatus which concerns on the 3rd Embodiment of this invention. The block diagram which shows a part of 2nd example of the communication apparatus which concerns on the 3rd Embodiment of this invention. The figure which shows the frequency-common mode current characteristic of the communication apparatus which concerns on the 3rd Embodiment of this invention. The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance for the communication apparatus which concerns on the 3rd Embodiment of this invention. Explanatory drawing which shows the power cable which concerns on the 4th Embodiment of this invention. The figure which shows the frequency-common mode current characteristic at the time of using the power cable which concerns on the 4th Embodiment of this invention for the communication apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows the frequency-common mode current characteristic when the impedance upper which has an unbalanced inductance, and the power cable which concerns on the 4th Embodiment of this invention are used for the communication apparatus which concerns on the 2nd Embodiment of this invention. Diagram showing current model on transmission line The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has the inductance (L1 = L2 = 220 microH) which is balanced. The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has the inductance (L1 = L2 = 330 microH) which is balanced. The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 100microH, L2 = 133microH) The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 100 (micro | micron | mu) H, L2 = 168 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 100microH, L2 = 200microH). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 220 (micro | micron | mu) H, L2 = 267 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 220 (micro | micron | mu) H, L2 = 288 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 220 (micro | micron | mu) H, L2 = 320 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 220 (micro | micron | mu) H, L2 = 370 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 220 (micro | micron | mu) H, L2 = 440 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 330microH, L2 = 398microH). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 330microH, L2 = 430microH). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 330 (micro | micron | mu) H, L2 = 480 (micro | micron | mu) H). The figure which shows the frequency-common mode current characteristic at the time of using the impedance upper which has an unbalanced inductance (L1 = 330 (micro | micron | mu) H, L2 = 550 (micro | micron | mu) H). Relationship diagram between L2 / L1 and ΔCMI (L1 = 100μH) Relationship diagram between L2 / L1 and ΔCMI (L1 = 220μH) Relationship diagram between L2 / L1 and ΔCMI (L1 = 330μH)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transmission part 2 Reception part 11a, 11b, 13b Inductor 12, 13a, 21a, 21b, 31, 32 Common mode choke coil 22, 281 Surge absorber 41, 42 Electric wire 100 Communication apparatus 101 Case 102 Power supply connector 103 Modular jack 104 Display Part 104a, 104b, 104c LED
200 circuit module 210 main IC
211 CPU
212 PLC / MAC block 213 PLC / PHY block 220 AFE / IC
221 D / A converter (DAC)
222 A / D converter (ADC)
223,224 Variable Amplifier (VGA)
230 Ethernet (registered trademark) PHY IC
240 memory 251 low-pass filter 252 driver IC
261 Band pass filter 270 Coupler 271 Coil transformer 271a Primary winding 271b Secondary winding 272a, 272b Coupling capacitor 282 Fuse 290, 291 Impedance upper 299 Branching unit 300 Switching power supply 301 AC / DC conversion unit 400 Power plug 500 Outlet 600 601 Power cable 900 Power line

Claims (16)

A power line connection section that can be connected to a power line that has at least two transmission lines and transmits power, and
A power supply unit that receives supply of the power via the power line connection unit;
An inductor section provided between the power line connection section and the power supply section,
The inductor section is
A first path having a first inductance and connected to one of the transmission lines;
A power supply apparatus comprising: a second path having a second inductance different from the first inductance and connected to a transmission line different from the transmission line connected to the first path. The power supply device according to claim 1,
The inductor unit includes a first inductor having the first inductance provided in the first path and a second inductor having the second inductance provided in the second path. Power supply. The power supply device according to claim 2,
The first inductor is a power supply device having a third inductor and a fourth inductor having a predetermined inductance. The power supply device according to claim 1,
The inductor unit includes a first coil unit provided in the first path and a second coil unit inserted in the second path and having a different number of turns from the first coil unit. A power supply device including a common mode choke coil. The power supply device according to claim 1,
The inductor section is
A common mode choke coil provided in each of the first path and the second path and having a coil portion having the same number of turns;
A power supply apparatus comprising: an inductor provided in any one of the first path and the second path. The power supply device according to any one of claims 1 to 5,
The inductor unit has a characteristic of attenuating a signal in a frequency band excluding at least an AC power source frequency. The power supply device according to any one of claims 1 to 6,
A fuse connected to the power line connection;
A first surge absorbing element connected to the inductor portion;
A power supply apparatus further comprising: a second common mode choke coil connected between the fuse and the first surge absorbing element. The power supply device according to claim 7,
The second common mode choke coil is a power supply device having a self-resonant frequency of 20 megahertz or more. The power supply device according to claim 7 or 8,
A power supply apparatus further comprising a second surge absorbing element provided between the fuse and the second common mode choke coil and having a capacity smaller than that of the first surge absorbing element. The power supply device according to any one of claims 1 to 9,
The power supply unit includes a power cable in which at least two electric wires connected to each of the transmission lines are twisted.   A power line communication apparatus comprising the power supply device according to claim 1. The power line communication device according to claim 11,
A transmission unit that outputs a transmission signal to be transmitted through the power line;
A coupler transformer having a secondary winding connected to the transmission unit, and a primary winding connected to a branching unit between the power line connection unit and the inductor unit to superimpose the transmission signal on the power line;
A capacitor unit connected to the primary winding of the coupler transformer and having a higher impedance in the frequency band of the AC voltage depending on the frequency band of the transmission signal;
A power line communication device further comprising: a third common mode choke coil connected between the capacitor unit and the transmission unit. The power line communication device according to claim 12,
The third common mode choke coil is a power line communication device connected between the capacitor unit and a primary winding of the coupler transformer. The power line communication device according to claim 12,
The third common mode choke coil is a power line communication device connected between the transmitter and a secondary winding of the coupler transformer. The power supply device according to claim 1,
The power supply apparatus according to claim 1, wherein a ratio between the second inductance and the first inductance is 1.21-2. The power supply device according to claim 15, wherein
The power supply apparatus according to claim 1, wherein a ratio between the second inductance and the first inductance is 1.3-2.

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