KR100454106B1 - Filter for power line communication - Google Patents

Abstract

The present invention relates to a filter for power line communication, comprising: first to third power lines and a neutral line for transmitting power; A first filter unit which blocks noise from outside and an internal signal from leaking out; A second filter unit connected to the first filter unit to block noise from outside and outflow of an internal signal to the outside; First to third nodes connected to the second filter part and formed on the first to third power lines, respectively; A third filter unit connected to the first to third nodes, and configured to block noise from outside and internal signal from flowing out; A fourth filter unit connected to the third filter unit to block noise from outside and outflow of an internal signal to the outside; And a fifth filter unit connected between the first to third nodes and the neutral line, and blocking a noise from flowing outside and an internal signal from flowing outside. Performs the function of a pass filter.

Description

Filter for power line communication

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter for power line communication, and more particularly, to a power line communication filter having a blocking filter function for blocking transmission of unwanted external noise and a pass function for signal transmission between abnormalities in three-phase four-wire power line communication.

Power line communication (PLC) refers to a technology for communicating voice and data on a high frequency signal of hundreds of [Hz] to several tens of [MHz] through a power line for supplying power. The application of power line communication technology enables home networking, information appliances, and grid management, and the industry expects that power line communication will enable new services and potential markets. In particular, high-speed access technology using power line communication and low-speed control technology through a home network are attracting attention as a next-generation communication technology from domestic and overseas communication companies and power companies.

Power line communication is more difficult to implement than data transmission using a communication cable or optical fiber because the power line communicates with the medium. In particular, it is difficult to pass data through limited transmission power while overcoming special environments such as high load and interference, noise, variable impedance and signal attenuation. In order to utilize the power line as a communication medium, a technology that accepts only a desired communication signal and removes various noise signals should be given. Blocking filters and pass filters are used as one of the methods to achieve this purpose.

The conventional blocking filter for three-phase four-wire power line communication includes inductors in each line through which power is transmitted, and capacitors between the lines and the neutral line. If the capacity increases in this state, a large capacity core must be used to maintain the inductance value, and the inductor must be configured by winding a power line many turns around the core.

As such, since a large number of inductors are used in the related art, a blocking filter cannot be made large, and in this state, communication between the abnormality of the power line communication region is not possible. Therefore, a separate pass filter must be manufactured and used.

Accordingly, the technical problem to be achieved by the present invention is to provide a filter for power line communication in which blocking and pass functions are improved without using a separate pass filter.

BRIEF DESCRIPTION OF THE DRAWINGS In order to better understand the drawings cited in the detailed description of the invention, a brief description of each drawing is provided.

1 is a circuit diagram of a power line communication filter according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a structure of a first filter unit or a fourth filter unit shown in FIG. 1.

FIG. 3 is a diagram illustrating a first embodiment of the structure of the second filter part or the third filter part shown in FIG. 1.

4 is a diagram illustrating a second embodiment of the structure of the second filter part or the third filter part shown in FIG. 1.

FIG. 5 is a diagram illustrating a third embodiment of the structure of the second filter part or the third filter part shown in FIG. 1.

6 is a circuit diagram of a power line communication filter according to a second embodiment of the present invention.

FIG. 7 is a diagram illustrating a first embodiment of the structure of the second filter unit or the third filter unit illustrated in FIG. 6.

FIG. 8 is a diagram illustrating a second embodiment of the structure of the second filter part or the third filter part shown in FIG. 6.

FIG. 9 is a diagram illustrating a third embodiment of the structure of the second filter unit or the third filter unit shown in FIG. 6.

<Explanation of symbols for the main parts of the drawings>

101,601 filters for power line communication, 124: neutral line

121 to 123: first to third power lines, and N1 to N3: first to third nodes

L1a to L11: inductors, C1 to C9: capacitors

211,311-313,411-413: magnetic cores, 511-513: ferrite cores

111 to 115,611 to 615: first to fifth filter parts

In order to achieve the above technical problem, the present invention, the first to third power lines and the neutral line for transmitting power; A first filter unit which blocks noise from outside and an internal signal from leaking out; A second filter unit connected to the first filter unit to block noise from outside and outflow of an internal signal to the outside; First to third nodes connected to the second filter part and formed on the first to third power lines, respectively; A third filter unit connected to the first to third nodes, and configured to block noise from outside and internal signal from flowing out; A fourth filter unit connected to the third filter unit to block noise from outside and outflow of an internal signal to the outside; And a fifth filter unit connected between the first to third nodes and the neutral line to block noise from outside and outflow of an internal signal to the outside.

Preferably, the first to fourth filter units each have an inductor connected to the first to third power lines.

Preferably, the second and third filter units each further include a capacitor connected in parallel with the inductor.

Preferably, the inductors provided in the second filter part respectively compensate for the inductances of the corresponding inductors of the first filter part, and the inductors provided in the third filter part each correspond to the inductors of the fourth filter part. Compensates for inductance.

Preferably, the fifth filter unit includes: a first capacitor and an inductor connected in series between the first node and the neutral line; A second capacitor and an inductor connected in series between the second node and the neutral line; And a third capacitor and an inductor connected in series between the third node and the neutral line.

Preferably, the first filter part, the second filter part, the first to third nodes, the third filter part and the fourth filter part are sequentially arranged.

In order to achieve the above technical problem, the present invention, the first to third power lines and the neutral line for transmitting power; A first magnetic core blocking noise from the outside and an internal signal from leaking to the outside and surrounding the first to third power lines; Second to fourth magnetic cores connected to a rear end of the first magnetic core, blocking noise from being introduced from the outside and an internal signal from leaking to the outside, and surrounding the first to third power lines, respectively; A fifth to seventh magnetics connected to rear ends of the second to fourth magnetic cores, respectively, to prevent noise from flowing out and an internal signal from leaking to the outside, and respectively surrounding the first to third power lines. Cores; An eighth magnetic core connected to the rear ends of the fifth to seventh magnetic cores, blocking noise from being introduced from the outside and leakage of an internal signal to the outside, and surrounding the first to third power lines; First to third nodes positioned between the second to fourth magnetic cores and the fifth to seventh magnetic cores, respectively, formed on the first to third power lines; First to third capacitors connected to the first to third nodes, respectively; And first to third inductors connected between the first to third capacitors and the neutral line, respectively.

Preferably, the second to fourth magnetic cores compensate for the inductance of the first magnetic core, and the fifth to seventh magnetic cores compensate for the inductance of the eighth magnetic core.

Preferably, the first to third capacitors and the first to third inductors block inflow of external noise and outflow of the internal signal.

Preferably, the second to seventh magnetic cores are respectively wound by a predetermined number of turns by the first to third power lines.

Preferably, the second to seventh magnetic cores each further include a capacitor connected in parallel.

In order to achieve the above technical problem, the present invention also comprises: first to third power lines and a neutral line for transmitting power; A first magnetic core surrounding the first to third power lines; First to third insulating cores connected to a rear end of the first magnetic core and wound by a predetermined number of turns by the first to third power lines; Fourth to sixth insulation cores connected to rear ends of the first to third insulation cores and wound around a predetermined number of turns by the first to third power lines; A second magnetic core connected to the rear ends of the fourth to sixth magnetic cores and surrounding the first to third power lines; First to third nodes positioned between the first to third insulation cores and the fourth to sixth insulation cores, respectively, formed on the first to third power lines; First to third capacitors connected to the first to third nodes, respectively; And first to third inductors connected between the first to third capacitors and the neutral line, respectively.

Preferably, the first to sixth insulating cores are ferrite cores.

Preferably, the first to sixth insulating cores each further include a capacitor connected in parallel.

The power line communication filter of the present invention performs the function of the blocking filter and the pass filter without a separate pass filter.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

1 is a circuit diagram of a power line communication filter according to the present invention. Referring to FIG. 1, the power line communication filter 101 may include first to third power lines 121 to 123, a neutral line 124, first to fifth filter parts 111 to 115, and first to fifth agents. Three nodes N1 to N3 are provided.

Power, such as 110 volts or 220 volts or more, is transmitted through the first to third power lines 121-123 and the neutral line 124. A load (not shown) is connected to the fourth filter unit 114.

The first filter unit 111 blocks outflow and outflow of unnecessary signals. That is, the first filter unit 111 blocks external noise from flowing into the load, and blocks the communication signal of the load from flowing out of the first filter unit 111. In addition, the first filter unit 111 passes a communication signal of a predetermined region among communication signals input to the first filter unit 111 from the outside. The first filter unit 111 includes inductors L1a to L1c connected to the first to third power lines 121 to 123.

The second filter unit 112 is adjacent to the first filter unit 111 and blocks the external flow of the unnecessary signal. The second filter unit 112 includes inductors L2 to L4 connected to the first to third power lines 121 to 123. The inductors L2 to L4 compensate for the inductance of the inductors L1a to L1c provided in the first filter unit 111 to compensate for the external inflow and outflow blocking of the unnecessary signal.

The first to third nodes N1 to N3 are formed adjacent to the second filter unit 112 of the first to third power lines 121 to 123.

The third filter unit 113 is adjacent to the first to third nodes N1 to N3 and blocks the external flow of the unnecessary signal. The third filter unit 113 includes inductors L5 to L7 connected to the first to third power lines 121 to 123. The inductors L5 to L7 compensate for the inductance of the inductors L8a to L8c provided in the fourth filter unit 114, respectively, to compensate for the external leakage / interception of the unnecessary signal.

The fourth filter unit 114 is adjacent to the third filter unit 113 and blocks the external flow of the unnecessary signal and passes the communication signal in the predetermined area. That is, the fourth filter unit 114 blocks external noise from flowing into the load, and blocks the communication signal of the load from flowing out of the power line communication filter 101. In addition, the fourth filter unit 114 passes a communication signal of a predetermined region among communication signals input to the fourth filter unit 114 from the outside of the power line communication filter 101. The fourth filter unit 114 includes inductors L8a to L8c connected to the first to third power lines 121 to 123.

The fifth filter unit 115 is connected between the first to third nodes N1 to N3 and the neutral line 124, and blocks outflow and outflow of the unnecessary signal. The fifth filter unit 115 includes first to third capacitors C1 to C3 and inductors L9 to L11. The first capacitor C1 and the inductor L9 are connected in series with each other. , Is connected between the first node N1 and the neutral line 124. The second capacitor C2 and the inductor L10 are connected in series with each other, and between the second node N2 and the neutral line 124. The third capacitor C3 and the inductor L11 are connected in series and are connected between the third node N3 and the neutral line 124.

The first filter part 111, the second filter part 112, the first to third nodes N1 to N3, the third filter part 113, and the fourth filter part 114 are sequentially arranged.

FIG. 2 is a diagram illustrating a structure of the first filter part 111 or the fourth filter part 114 shown in FIG. 1. Referring to FIG. 2, the first filter unit 111 or the fourth filter unit 114 includes a cylindrical magnetic core 211 surrounding the first to third power lines 121 to 123. Accordingly, the first filter unit 111 or the fourth filter unit 114 not only performs a function of a blocking filter that blocks external flow of unnecessary signals, but also communicates the predetermined region by mutual induction of the magnetic core 211. It also performs the function of a pass filter that passes a signal.

3 is a diagram illustrating a first embodiment of the structure of the second filter part 112 or the third filter part 113 shown in FIG. 1. Referring to FIG. 3, the second filter unit 112 or the third filter unit 113 includes magnetic cores 311 to 313 surrounding one of the first to third power lines 121 to 123. The magnetic cores 311 to 313 surround one of the first to third power lines 121 to 123 and thus have a smaller size. Since the magnetic cores 311 to 313 are small, the size of the power line communication filter (101 in FIG. 1) is also reduced.

4 is a diagram illustrating a second embodiment of the structure of the second filter part 112 or the third filter part 113 shown in FIG. 1. Referring to FIG. 4, the second filter unit 112 or the third filter unit 113 includes magnetic cores 411 to 413 surrounding one of the first to third power lines 121 to 123. At this time, the magnetic cores 411 to 413 are wound by a predetermined number of turns by the first to third power lines 121 to 123. The inductance of the inductors (L2 to L4 or L5 to L7 in FIG. 1) varies depending on the number of turns. That is, when the number of turns is large, the inductance of the inductors L2 to L4 or L5 to L7 is increased, and when the number of turns is small, the inductance of the inductors L2 to L4 or L5 to L7 is decreased. As described above, since the size of the second filter portion 112 and the third filter portion 113 is small, the size of the power line communication filter (101 in FIG. 1) becomes small.

FIG. 5 is a diagram illustrating a third embodiment of the structure of the second filter part or the third filter part shown in FIG. 1. Referring to FIG. 5, the second filter part 112 or the third filter part 113 may be insulated cores wound by a predetermined number of turns by one of the first to third power lines 121 to 123, for example, a ferrite. Cores 511 to 513 are provided. The inductance of the inductors (L2 to L4 or L5 to L7 in FIG. 1) varies depending on the number of turns. That is, when the number of turns is large, the inductance of the inductors L2 to L4 or L5 to L7 is increased, and when the number of turns is small, the inductance of the inductors L2 to L4 or L5 to L7 is decreased. By configuring in this way, adjustment of inductance is easy. In addition, the filter parts 112 and 113 are provided with ferrite cores so that the current is not saturated, and thus the filter parts 112 and 113 are used regardless of the current capacity.

6 is a circuit diagram of a power line communication filter according to a second embodiment of the present invention. Referring to FIG. 6, the power line communication filter 601 may include first to third power lines 621 to 623, a neutral line 624, first to fifth filter units 611 to 615, and first to fifth agents. Three nodes N4 to N6 are provided.

The configuration and function of the first to third power lines 621 to 623, the neutral line 624, the first to fifth filter units 611 to 615, and the first to third nodes N1 to N3 are described. The first to third power lines 121 to 123, the neutral line 124, the first to fifth filter parts 111 to 115, and the first to third nodes N1 to N3 shown in FIG. 1, respectively. ), Duplicate descriptions will be omitted. However, the structures of the second and third filter parts 612 and 613 are different from those of the second and third filter parts 112 and 113 shown in FIG. 1.

The second and third filter units 612 and 613 include inductors L2 to L7 and capacitors C4 to C9 connected in parallel, respectively. As such, by connecting the inductors L2 to L7 and the capacitors C4 to C9 in parallel, the inductance becomes larger than when only the inductors L2 to L7 are connected.

FIG. 7 is a view illustrating a first embodiment of the structure of the second filter unit or the third filter unit shown in FIG. 6, and FIG. 8 is a second of the structure of the second filter unit or the third filter unit shown in FIG. 6. FIG. 9 is a view showing an embodiment, and FIG. 9 is a view showing a third embodiment of the structure of the second filter part or the third filter part shown in FIG. 6.

The inductors L2 to L7 shown in FIGS. 7 to 9 are the same in structure as the inductors L2 to L7 shown in FIGS. 3 to 5, respectively. However, the second filter part 612 or the third filter part 613 illustrated in FIGS. 7 to 9 further include capacitors C4 to C9, and one capacitor is connected in parallel to one inductor. have. Capacitors C4 to C9 are electrically connected to first to third power lines 621 to 623.

The best embodiments have been disclosed in the drawings and the specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, according to the present invention, the power line communication filters 101 and 601 include the first to the fifth filter units 111 to 115, 611 to 615 to influence the communication performance of the power line communication during the three-phase four-wire power line communication. The function of the blocking filter to block noise and to prevent the leakage of the communication signal to the outside, and to pass the communication signal of a predetermined area among the communication signals input from the outside to enable communication between abnormalities in the building, which is a power line communication area. Performs the function of a pass filter. In addition, since the sizes of the inductors L1a to L11 provided in the first to fifth filter parts 111 to 115, 611 to 615 are small, the sizes of the power line communication filters 101 and 101 are reduced, and the power lines 121 to 124 and 621 to. Since it is not affected by the capacity of 624, the blocking rate of unnecessary signals is increased and the path function of the communication signal in the predetermined area can be completely performed.

Claims (14)

First to third power lines and a neutral line for transmitting power; A first filter unit which blocks noise from outside and an internal signal from leaking out; A second filter unit connected to the first filter unit to block noise from outside and outflow of an internal signal to the outside; First to third nodes connected to the second filter part and formed on the first to third power lines, respectively; A third filter unit connected to the first to third nodes, and configured to block noise from outside and internal signal from flowing out; A fourth filter unit connected to the third filter unit to block noise from outside and outflow of an internal signal to the outside; And And a fifth filter unit connected between the first to third nodes and the neutral line to block noise from outside and outflow of an internal signal to the outside. The filter of claim 1, wherein each of the first to fourth filter units includes an inductor connected to the first to third power lines, respectively. The filter of claim 2, wherein each of the second and third filter units further includes a capacitor connected in parallel with the inductor. 3. The inductor of claim 2, wherein the inductors of the second filter unit compensate for inductances of the corresponding inductors of the first filter unit, respectively, and the inductors of the third filter unit are respectively corresponding inductors of the fourth filter unit. Power line communication filter, characterized in that to compensate for the inductance of the. The method of claim 1, wherein the fifth filter unit A first capacitor and an inductor connected in series between the first node and the neutral line; A second capacitor and an inductor connected in series between the second node and the neutral line; And And a third capacitor and an inductor connected in series between the third node and the neutral line. The filter of claim 1, wherein the first filter part, the second filter part, the first to third nodes, the third filter part, and the fourth filter part are sequentially arranged. First to third power lines and a neutral line for transmitting power; A first magnetic core blocking noise from the outside and an internal signal from leaking to the outside and surrounding the first to third power lines; Second to fourth magnetic cores connected to a rear end of the first magnetic core, blocking noise from being introduced from the outside and an internal signal from leaking to the outside, and surrounding the first to third power lines, respectively; A fifth to seventh magnetics connected to rear ends of the second to fourth magnetic cores, respectively, to prevent noise from flowing out and an internal signal from leaking to the outside, and respectively surrounding the first to third power lines. Cores; An eighth magnetic core connected to the rear ends of the fifth to seventh magnetic cores, blocking noise from being introduced from the outside and leakage of an internal signal to the outside, and surrounding the first to third power lines; First to third nodes positioned between the second to fourth magnetic cores and the fifth to seventh magnetic cores, respectively, formed on the first to third power lines; First to third capacitors connected to the first to third nodes, respectively; And And first to third inductors respectively connected between the first to third capacitors and the neutral line. The power line of claim 7, wherein the second to fourth magnetic cores compensate for the inductance of the first magnetic core, and the fifth to seventh magnetic cores compensate for the inductance of the eighth magnetic core. Communication filter. 8. The power line communication filter of claim 7, wherein the first to third capacitors and the first to third inductors block noise from outside and internal signal from leaking out. 8. The power line communication filter of claim 7, wherein the second to seventh magnetic cores are wound by a predetermined number of turns by the first to third power lines, respectively. The filter of claim 7, wherein each of the second to seventh magnetic cores further includes a capacitor connected in parallel. First to third power lines and a neutral line for transmitting power; A first magnetic core surrounding the first to third power lines; First to third insulating cores connected to a rear end of the first magnetic core and wound by a predetermined number of turns by the first to third power lines; Fourth to sixth insulation cores connected to rear ends of the first to third insulation cores and wound around a predetermined number of turns by the first to third power lines; A second magnetic core connected to the rear ends of the fourth to sixth magnetic cores and surrounding the first to third power lines; First to third nodes positioned between the first to third insulation cores and the fourth to sixth insulation cores, respectively, formed on the first to third power lines; First to third capacitors connected to the first to third nodes, respectively; And And first to third inductors respectively connected between the first to third capacitors and the neutral line. 13. The power line communication filter of claim 12, wherein the first to sixth insulating cores are ferrite cores. The filter of claim 12, wherein each of the first to sixth insulation cores further includes a capacitor connected in parallel.