JP2009284159A - Power line communication apparatus and method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power line communication apparatus that achieves mutual synchronization by using zero-crossing timing of a commercial power source. <P>SOLUTION: The power line communication apparatus 1A includes a pair of electric paths 17 for connections with a power line, an impedance upper portion 10 which is provided at a predetermined position on the pair of electric paths 17 and has low impedance at a commercial frequency and high characteristics at a frequency used for power line communication, a zero-crossing detection unit 11 which is provided on the pair of electric paths 17 and behind the impedance upper portion 10 and detects zero-crossing timing of the commercial power source, a capacitor C1 provided between the impedance upper portion 10 and zero-crossing detection unit 11 and between the pair of electric paths 17, and a coupling unit 13 and a power line communication unit 14 which are connected to the pair of electric paths 17 and perform the power line communication. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power line carrier communication apparatus that performs communication using a power line that supplies power as a transmission path.

  In recent years, networking has progressed in various technical fields due to advances in communication technology, and various electrical devices (including electronic devices, the same applies hereinafter) in buildings are being connected to the network. In this networking, there is an advantage that it is not necessary to install a new transmission line because the existing wiring is used, and the initial cost associated with the introduction is accordingly low, and the aesthetics of the building are not impaired. Therefore, power line communication (Powre Line Communication, hereinafter abbreviated as “PLC”) using a power line for supplying power to these electric devices as a transmission line has been actively researched and developed. This PLC is a communication system that performs transmission and reception by superimposing a PLC communication signal having a frequency higher than the commercial frequency on the power waveform of the commercial power supply. In recent years, relaxation of PLC-related laws and regulations has been studied for the purpose of enabling high-speed communication such as the Internet, and in addition to the frequency band of 10 kHz to 450 Hz that can be used with conventional PLC, The use of the 2 MHz to 30 MHz frequency band is considered, and the PLC is connected to the PLC using a high speed PLC that performs a PLC using a communication signal in the 2 MHz to 30 MHz frequency band and a communication signal in the 10 kHz to 450 kHz frequency band. Low speed PLC to perform is known.

On the other hand, in a communication system including a plurality of communication devices, the communication device operates intermittently by switching between an operation state called an active state and a standby state called a sleep state for the purpose of power saving. It is configured to perform operations. In such a communication system, it is necessary to synchronize the start timing of the operation state in each communication device in order to perform communication between the communication devices. Such synchronization methods include, for example, a method in which each communication device is provided with a relatively high-precision clock that performs timekeeping, and the time of each clock of each communication device is synchronized with each other. A time management device that manages the reference time in the system is provided, and each communication device acquires time information from the time management device through communication to correct each other's time while correcting the time of the communication device, etc. (For example, refer to Patent Document 1).
JP 2004-096429 A

  Even when the communication system is configured by using a power line carrier communication apparatus that performs PLC, it is necessary to synchronize each power line carrier communication apparatus. In the above-described method in which a clock is provided in each power line carrier communication device, a relatively high accuracy timepiece is required, so that the cost of the power line carrier communication device is increased. In addition, in PLC, it may be difficult to send and receive communication signals depending on when the power line is in a low impedance state due to the electrical equipment being connected to the power line or when noise from the electrical equipment is placed on the power line. For this reason, it is difficult to adopt the above-described method of providing a time management device in a communication system.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a power line carrier communication device that can synchronize with each other by using zero-cross timing of a commercial power source.

  As a result of various studies, the present inventor has found that the above object is achieved by the present invention described below. That is, a power line carrier communication device according to one aspect of the present invention is provided with a pair of electric circuits for connecting to a power line, and a predetermined position on the pair of electric lines, and has a low impedance with respect to a commercial frequency and a power line carrier communication. Impedance upper part having high characteristics with respect to the frequency used for the above and a pair of electric circuits on the rear stage of the impedance upper part and operated based on the zero cross timing detected by the detection part A detection unit for detecting a zero crossing timing of a commercial power source, a capacitor provided between the pair of electric circuits between the impedance upper unit and the detection unit, and the power line carrier communication connected to the pair of electric circuits And a communication unit.

  In the power line carrier communication apparatus having such a configuration, an intermittent operation that repeats the operation state and the standby state is performed according to the zero cross timing of the commercial power source detected by the detection unit, and the PLC is performed in the operation state. Therefore, the power line carrier communication apparatus having such a configuration can perform PLC in synchronization with other power line carrier communication apparatuses while saving power.

  In addition, a power line carrier communication device according to another aspect of the present invention is configured to extract a communication signal of a power line carrier communication that transmits a power line carrier communication and a pair of electric circuits for connection to the power line, and to the power line. And a power line carrier communication unit that demodulates the communication signal of the power line carrier communication taken out by the joint unit and modulates data into a communication signal of the power line carrier communication and outputs the data to the joint unit. The coupling unit includes a detection unit that detects a zero cross timing of a commercial power supply, and the power line carrier communication unit operates based on the zero cross timing detected by the detection unit.

  In the power line carrier communication apparatus having such a configuration, an intermittent operation that repeats the operation state and the standby state is performed according to the zero cross timing of the commercial power source detected by the detection unit, and the PLC is performed in the operation state. Therefore, the power line carrier communication apparatus having such a configuration can perform PLC in synchronization with other power line carrier communication apparatuses while saving power.

  In the power line carrier communication apparatus having such a configuration, since the detection unit is included in the coupling unit, it is possible to separate the power supply portion and the communication portion. For this reason, it becomes possible to employ | adopt as a power supply part the power supply unit with which it is difficult to mount a detection part.

  In the above power line carrier communication device, the coupling unit includes a coupling capacitor having a high impedance with respect to a commercial frequency, and a primary winding connected in series with the coupling capacitor, so that the communication signal component of the power line carrier communication And a coupling transformer that can transmit from the primary side to the secondary side, and the detection unit includes a photocoupler connected in series to the primary side of the coupling transformer and capable of receiving AC power. Features.

  According to this configuration, the coupling unit includes the coupling capacitor and the coupling transformer connected in series, and the photocoupler of the detection unit is connected in series to the coupling transformer. For this reason, a current restricted by the impedance of the coupling capacitor, which has a high impedance with respect to the commercial frequency, flows through the detection unit, and the detection unit detects a zero cross by the current waveform of the commercial power source flowing through the coupling capacitor. It will be. Therefore, since the drive current value of the detection unit can be determined not by the resistor element but by the capacitor, the power consumption can be reduced by the amount of power consumed by the resistor element.

  Further, in the above power line carrier communication device, the detection unit includes a capacitor that is provided between a pair of input terminals of the photocoupler and has a low impedance with respect to a frequency used for the power line carrier communication. And

  According to this configuration, the capacitor is provided between the pair of input terminals of the photocoupler. For this reason, even when the commercial power supply is in the vicinity of 0 V and the photocoupler operates in the cutoff region, the PLC communication signal can be superimposed on the electric circuit (power line) via the capacitor. For this reason, even if the time of the operation state is set to a length including the zero cross of the commercial power supply, the PLC can be performed. Therefore, there is no restriction on the time setting of the operating state, and it becomes possible to transmit a PLC communication signal accommodating a relatively large size data.

  In the above power line carrier communication device, the coupling unit includes a coupling capacitor having a high impedance with respect to a commercial frequency, and a primary winding connected in series with the coupling capacitor, so that the communication signal component of the power line carrier communication And a coupling transformer that can transmit from the primary side to the secondary side, and the detection unit includes a resistance element and a photocoupler connected in series with the resistance element and capable of receiving AC power, The resistor element and the photocoupler connected in series are connected in parallel to the coupling capacitor.

  According to this configuration, the resistance element and the photocoupler connected in series in the detection unit are connected in parallel to the coupling capacitor of the coupling unit. Therefore, only one capacitor is required at the coupling portion. Therefore, the number of parts in the coupling portion can be reduced correspondingly, and the mounting area can be reduced accordingly.

  Moreover, in the above-described power line carrier communication apparatus, the coupling unit has a four-winding configuration in which the primary side is two windings and the secondary side is two windings, and the communication signal component of the power line carrier communication is primary. A coupling transformer that is capable of transmitting from the side to the secondary side, and a coupling capacitor that is provided between the two windings on the primary side and that has a high impedance with respect to a commercial frequency. An element and a photocoupler connected in series with the resistance element and capable of inputting AC power, and the resistance element and the photocoupler connected in series are connected in parallel to the coupling capacitor. Features.

  According to this configuration, since the coupling capacitor is provided between the two primary windings in the coupling transformer, the four-winding coupling transformer is connected to the pair of electric circuits (power lines) with the coupling capacitor as the center. Are symmetrical. For this reason, balanced transmission is possible, and noise resistance can be improved.

  In the power line carrier communication apparatus of the present invention, mutual synchronization can be achieved by utilizing the zero cross timing of the commercial power supply.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted.

(First embodiment)
FIG. 1 is a diagram illustrating a configuration of a power line carrier communication apparatus according to the first embodiment. In FIG. 1, a power line carrier communication device 1 </ b> A includes an impedance upper unit 10, a capacitor C <b> 1, a zero cross detection unit 11, a power source unit 12, a coupling unit 13, and a power line carrier communication unit (hereinafter abbreviated as “PLC unit”). 14), a control unit 15, an input / output unit (hereinafter abbreviated as "I / O unit") 16, and a pair of electric circuits 17 (17a, 17b).

  The pair of electric paths 17 includes two conductor lines 17a and 17b for connecting to a power line (not shown). The conductor wires 17a and 17b include, for example, metal conductors provided on a printed circuit board and wiring such as so-called lead wires and cables. The power line is a wiring for supplying power by a commercial power source such as a commercial power source of 100V between lines or a commercial power source of 200V between lines. For example, the power line is installed in each door of a detached house or an apartment house. The pair of electric circuits 17 may be directly connected to the power line, or may be connected to an outlet provided on the power line via a plug provided at one end of the pair of electric circuits 17.

  The impedance upper unit 10 is provided at a predetermined position on the pair of electric paths 17, and the impedance thereof is low with respect to a commercial frequency (for example, 50 Hz or 60 Hz) of a commercial power source and is abbreviated as “PLC”. ) Is a circuit having high characteristics with respect to the frequency used. The low impedance characteristic with respect to the commercial frequency of the commercial power supply means that there is little loss due to impedance. The high impedance characteristic with respect to the frequency used for the PLC means that when the power line carrier communication apparatus 1A is connected to the power line, the influence on the transmission distance of the PLC communication signal transmitted through the power line is small. The frequency used for the PLC is, for example, a frequency in a low-speed PLC frequency band or a frequency in a high-speed PLC frequency band as described above. The impedance upper unit 10 includes, for example, a pair of inductors L1 and L2 provided between a pair of input terminals and a pair of output terminals. The pair of inductors L1 and L2 has low impedance with respect to the commercial frequency and high impedance characteristics with respect to the frequency used for the PLC.

  The zero-cross detection unit 11 is a circuit that is provided on the pair of electric circuits 17 and at the subsequent stage of the impedance upper unit 10, detects the zero-cross timing of the commercial power supply, and outputs a pulse in synchronization with the detected zero-cross timing. is there. In the present specification, the power line side viewed from the impedance upper unit 10 is referred to as a front stage, and the side opposite to the power line side viewed from the impedance upper section 10 is referred to as a rear stage. The zero cross timing of the commercial power supply is the time when the voltage waveform of the commercial power supply becomes 0V.

  The zero-cross detection unit 11 includes, for example, a resistance element Rc1, a photocoupler PC whose input side is connected in series to the resistance element Rc1, a resistance element Rc2 connected in series to the input side of the photocoupler PC, and the photocoupler PC. And a resistive element Rb connected in series on the output side. The series connection circuit of the resistor element Rc1, the photocoupler PC, and the resistor element Rc2 is connected between the pair of input terminals, and is therefore connected between the pair of electric circuits 17 (between the electric circuit 17a and the electric circuit 17b). . A power supply unit 12 is connected to the resistance element Rb, and a voltage is applied from the power supply unit 12 to the output side of the photocoupler PC via the resistance element Rb. The resistance elements Rc1 and Rc2 are current limiting resistors for the photocoupler PC. Instead of the two resistance elements Rc1 and Rc2, the current limiting resistance of the photocoupler PC may be constituted by one resistance element Rc. However, the withstand voltage of the resistance element is lowered and the pair of electric circuits 17 is balanced. As described above, the two resistance elements Rc1 and Rc2 are preferable as in this embodiment. The photocoupler PC is an AC input-compatible photocoupler capable of inputting AC power, and is provided on the input side, two light emitting diodes LED1 and LED2 connected in reverse parallel, and provided on the output side. Light emitting diodes LED1 and LED2 and a photodiode PD disposed at a position where the light emitted from the LED2 can be received. In the photocoupler PC corresponding to the AC input having such a configuration, the light emitting diode LED1 emits light in the positive half cycle of the commercial power supply, and the emitted light is received by the photodiode PD. In the negative half cycle of the commercial power supply, The light emitting diode LED2 emits light, and the emitted light is received by the photodiode PD. Therefore, in the zero cross detection unit 11 including the photocoupler PC corresponding to the AC input, the zero cross timing at which the commercial power source switches from the positive half cycle to the negative half cycle, and the zero cross at which the negative half cycle switches to the positive half cycle. A pulse is output in synchronization with the timing.

  The capacitor C1 is provided between the pair of electric circuits 17 (between the electric circuit 17a and the electric circuit 17b) between the impedance upper unit 10 and the zero cross detection unit 11. Since the capacitor C1 constitutes the low-pass filter with the inductors L1 and L2 of the impedance upper unit 10, the impedance is sufficiently high with respect to the commercial frequency of the commercial power supply and sufficiently low with respect to the frequency higher than the commercial frequency. Has impedance characteristics.

  The power supply unit 12 is a circuit that is connected to the pair of electrical paths 17 and generates a DC power source to be used in the power line carrier communication apparatus 1 </ b> A from a commercial power source supplied by the pair of electrical paths 17. The power supply unit 12 is connected to the power line by a pair of electric paths 17 through the zero cross detection unit 11, the capacitor C1, and the impedance upper unit 10. In the present embodiment, for example, the power supply unit 12 supplies the generated DC power to the zero cross detection unit 11, the PLC unit 14, the control unit 15, and the I / O unit 16. The power supply unit 12 includes, for example, a rectifier circuit that rectifies alternating current to direct current, a smoothing capacitor that smoothes the output of the rectifier circuit, and a DC-DC converter that boosts or steps down the output of the smoothing capacitor to a predetermined voltage level. Composed.

  The coupling unit 13 is a circuit that is connected to the pair of electric circuits 17 and extracts a PLC communication signal transmitted through the electric circuit 17 and superimposes the PLC communication signal on the electric circuit 17. The coupling unit 13 includes, for example, a coupling capacitor Cr having a sufficiently high impedance with respect to the commercial frequency of the commercial power source, and a primary winding connected in series with the coupling capacitor Cr, so that the communication signal component of the PLC is transmitted from the primary side. A coupling transformer T1 capable of transmitting to the secondary side is provided. The series connection circuit of the coupling capacitor Cr and the coupling transformer T <b> 1 is connected between the pair of input terminals, and is therefore connected between the pair of electric paths 17. The communication signal component of the PLC is electrically connected between the input side and the output side of the coupling unit 13 by the coupling transformer T1, while the frequency component of the commercial power supply is electrically connected between the input side and the output side of the coupling unit 13. Insulated. In the case where electrical insulation is not required between the input side and the output side of the coupling unit 13, an inductor may be used instead of the coupling transformer T1.

  The PLC unit 14 is a circuit that is connected to the coupling unit 13, demodulates the reception data from the PLC communication signal extracted by the coupling unit 13, modulates the transmission data into a PLC communication signal, and outputs the modulated data to the coupling unit 13. is there. The PLC unit 14 includes, for example, a receiving circuit that demodulates received data from a PLC communication signal extracted by the combining unit 13, and a transmission circuit that modulates transmission data into a PLC communication signal and outputs the PLC communication signal to the combining unit 13. Configured. The receiving circuit includes, for example, a band-pass filter that is connected to the secondary side of the coupling transformer T1 and transmits the frequency band of the PLC, and an amplifier that amplifies the output of the band-pass filter and outputs it to the control unit 15. The transmission circuit is configured by, for example, a bandpass filter that is connected to the control unit 15 and transmits the frequency band of the PLC, and an amplifier that amplifies the output of the bandpass filter and outputs the amplified output to the secondary side of the coupling transformer T1. It is configured with.

  The coupling unit 13 and the PLC unit 14 constitute an example of a communication unit that is connected to a pair of electric circuits and performs PLC.

  The control unit 15 includes, for example, a microprocessor and its peripheral circuits, and performs the PLC so as to operate based on the zero-cross timing detected by the zero-cross detection unit 11, and the PLC unit 14 and the I / O unit 16 is a circuit for controlling each part such as 16. The control unit 15 receives a pulse output from the zero cross detection unit 11 in synchronization with the zero cross timing, and performs an intermittent operation of the PLC based on the pulse.

  The I / O unit 16 is an interface circuit for inputting / outputting data between the power line carrier communication apparatus 1A and an external device. Data input to the I / O unit 16 is output to the PLC unit 14 via the control unit 15, and is modulated into a PLC communication signal by the PLC unit 14. Further, the data accommodated in the PLC communication signal demodulated by the PLC 14 is output to the I / O unit 16 via the control unit 15. The control unit 15 performs predetermined processing on the data as necessary. External devices are, for example, sensors such as fire alarms, crime prevention sensors and human sensors, home appliances such as lighting equipment and air conditioners, and dwelling equipment. The data includes detection output of sensors, on / off information of home appliances and dwelling equipment, and control signals of sensors, home appliances and dwelling equipment.

  FIG. 2 is a time chart illustrating the operation of the power line carrier communication apparatus according to the embodiment. 2A is a voltage waveform of a commercial power supply, FIG. 2B is an input voltage waveform of the zero cross detector 11, and FIG. 2C is a zero cross timing pulse output from the zero cross detector 11. , (D) is the state of the power line carrier communication device, and (E) is a PLC signal.

  The power line carrier communication apparatus 1A having such a configuration performs intermittent operation in which the operation state and the standby state are repeated according to the zero-cross timing of the commercial power supply detected by the zero-cross detection unit 11, and performs PLC in the operation state.

  More specifically, a commercial power supply having a voltage waveform shown in FIG. 2A is input to the impedance upper unit 10 and the coupling unit 13 from the power line. The voltage waveform of the commercial power supply has a period Tc, and a PLC communication signal or noise is superimposed on the waveform, for example.

  The inductors L1 and L2 of the impedance upper unit 10 and the capacitor C1 provided in the subsequent stage form a low-pass filter, and a frequency higher than the commercial frequency from the voltage waveform of the commercial power source input to the impedance upper unit 10 by the low-pass filter. The component is cut (filtered), and the voltage waveform shown in FIG.

  The zero-cross detector 11 detects the zero-cross timing from the voltage waveform of the commercial power supply from which the high-frequency component shown in FIG. 2B is cut. As shown in FIG. 2C, a pulse is generated according to the detected zero-cross timing. Is output to the control unit 15.

  The commercial power supply of the power line is supplied to the power supply unit 12 through the impedance upper unit 10, the capacitor C <b> 1, and the zero cross detection unit 11. The power supply unit 12 generates a DC power supply having a predetermined voltage level from the commercial power supply, and the generated DC power supply is supplied to, for example, the zero cross detection unit 11, the PLC unit 14, the control unit 15, and the I / O unit 16. .

  Then, when a pulse corresponding to the zero cross timing is input from the zero cross detection unit 11, the control unit 15 responds to the input pulse in order to perform communication with the PLC as shown in FIG. The PLC unit 14 and the I / O unit 16 are set in an operating state for a predetermined time set in advance at the start timing. For example, when data is input from the I / O unit 16 to the control unit 15 during this operation state, the control unit 15 processes the data as necessary and outputs the data to the PLC unit 14. This data is modulated into a PLC communication signal by the PLC unit 14, and the modulated PLC communication signal is output to the coupling unit 13 and transmitted to the power line by superimposing the electric circuit 17 in the coupling unit 13. Is done. Further, during this operation state, for example, when a PLC communication signal is extracted from the electric circuit 17 by the coupling unit 13, the extracted PLC communication signal is output to the PLC unit 14 and demodulated into data by the PLC unit 14. Is done. The demodulated data is output to the control unit 15, processed as necessary by the control unit 15, and output to the I / O unit 16. Then, when a predetermined time in the operating state has elapsed, the control unit 15 places the PLC unit 14 and the I / O unit 16 in a standby state. In this embodiment, the standby state is continued for a time until a pulse corresponding to the zero cross timing is next input from the zero cross detection unit 11. Among the circuits that operate by receiving power supply from the power supply unit 12, in the operating state, each unit necessary for performing the PLC operates by receiving power supply from the power supply unit 12, consumes power, and in the standby state Since no PLC is used, basically, only the circuit for returning from the standby state to the operating state operates, and the other circuits stop operating without receiving power supply from the power supply unit 12. And no power is consumed. For this reason, power saving can be achieved by intermittent operation. For example, in this embodiment, in the operating state, each unit of the zero cross detection unit 11, the PLC unit 14, the control unit 15, and the I / O unit 16 operates by receiving power supply from the power supply unit 12, and consumes power. In the standby state, each unit of the zero cross detection unit 11 and the control unit 15 operates by receiving power supply from the power supply unit 12.

  Next, when a pulse corresponding to the zero cross timing is input from the zero cross detection unit 11, the control unit 15 similarly causes the PLC unit 14 and the I / O unit 16 to operate according to the pulse, and When the predetermined time has elapsed, the PLC unit 14 and the I / O unit 16 are set in a standby state.

  By operating in this way, the power line carrier communication device 1A performs an intermittent operation that repeats the operation state and the standby state in accordance with the zero cross timing of the commercial power source detected by the zero cross detection unit 11, and the PLC in the operation state I do. Therefore, the power line carrier communication device 1A can perform PLC in synchronization with the other power line carrier communication device 1A while saving power.

  Further, in the power line carrier communication apparatus 1A of the present embodiment, the zero cross is counted (counted) as described later without configuring a clock unit that measures time such as date and time based on a pulse corresponding to the zero cross timing. However, the count value of the zero cross and the time are not associated with each other, and the start timing of the operation state is determined based on the pulse corresponding to the zero cross timing. For this reason, the control process of the control unit 15 can be simplified in performing the intermittent operation.

  In the power line carrier communication apparatus 1A of the present embodiment, the frequency component higher than the commercial frequency is cut by the low-pass filter. For this reason, even when noise generated by, for example, home appliances is superimposed on the commercial power source of the power line, this noise can be cut and a commercial power source with less noise can be input to the zero cross detection unit 11 It becomes. Therefore, the zero cross detector 11 can detect the zero cross timing of the commercial power supply more accurately. For this reason, it becomes possible to take mutual synchronization more accurately and stably between the power line carrier communication apparatuses 1A. Further, since the low-pass filter is also used as the inductors L1 and L2 of the impedance upper section 10, the number of parts can be reduced correspondingly, and the mounting area can be reduced correspondingly.

  In the above embodiment, the operation state and the standby state are repeated for each zero cross of the commercial power supply. However, the present invention is not limited to this, and the start timing of the operation state is synchronized with the zero cross timing of the commercial power supply. Just do it. For example, by counting zero crosses, the operation state may be started at every zero cross timing, for example, every other zero cross timing or every other zero cross timing. In the above-described embodiment, the operation state time is within the half cycle Tc / 2 of the commercial power supply, but is not limited to this and may be an arbitrary time. For example, it may be a time exceeding one cycle Tc of the commercial power source, a time exceeding two cycles 2Tc of the commercial power source, or the like. Moreover, when communicating by PLC, the time of the next operation state may be first notified to the communication destination by the first communication signal, and the time of the operation state notified by the first communication signal may be used. By configuring the operation state time to be arbitrarily changeable in this way, relatively large capacity data can be communicated. The same applies to the following embodiments.

  Next, another embodiment will be described.

(Second Embodiment)
FIG. 3 is a diagram illustrating a configuration of the power line carrier communication apparatus according to the second embodiment. In FIG. 3, the power line carrier communication device 1B includes an impedance upper unit 10, a power source unit 12, a coupling unit 21A, a PLC unit 14, a control unit 15, an I / O unit 16, and a pair of electric circuits 17 (17a, 17b), and the coupling unit 21A includes a zero-cross detection unit 211A.

  In the power line carrier communication apparatus 1A according to the first embodiment, the zero cross detector 11 is provided at the subsequent stage of the impedance upper part 10. However, in the power line carrier communication apparatus 1B according to the second embodiment, the zero cross detector 211A is the coupling part. 21A.

  For this reason, the impedance upper unit 10, the power supply unit 12, the PLC unit 14, the control unit 15, and the I / O unit 16 in the power line carrier communication device 1 </ b> B are connected to each other by the power supply unit 12 via the impedance upper unit 10 and the pair of electric circuits 17. Except for the point connected to the power line, it is the same as the impedance upper unit 10, the power supply unit 12, the PLC unit 14, the control unit 15 and the I / O unit 16 in the power line carrier communication device 1A of the first embodiment. Description is omitted.

  The coupling unit 21A is a circuit that is connected to the pair of electric circuits 17, extracts a PLC communication signal transmitted through the electric circuit 17, and superimposes the PLC communication signal on the electric circuit 17, and includes a zero-cross detection unit 211A. The coupling unit 21A includes, for example, a coupling capacitor Cr having a sufficiently high impedance with respect to the commercial frequency of the commercial power source, and a primary winding connected in series with the coupling capacitor Cr, so that the communication signal component of the PLC is transmitted from the primary side. A coupling transformer T1 that can transmit to the secondary side, and a zero-cross detector 211A whose input side is connected in series to the primary winding are configured. A series connection circuit of the coupling capacitor Cr, the coupling transformer T1, and the zero-cross detection unit 211A is connected between the pair of input terminals, and is therefore connected between the pair of electric circuits 17. The PLC unit 14 is connected to the secondary side of the coupling transformer T1.

  The zero cross detection unit 211A is a circuit that detects a zero cross timing of the commercial power supply and outputs a pulse in synchronization with the detected zero cross timing. The zero cross detection unit 211A outputs a pulse synchronized with the zero cross timing to the control unit 15. The zero-cross detection unit 211A includes, for example, a photocoupler PC corresponding to an AC input and a resistance element Rb connected in series to the output side of the photocoupler PC. A power supply unit 12 is connected to the resistance element Rb, and a voltage is applied from the power supply unit 12 to the output side of the photocoupler PC via the resistance element Rb.

  In the power line carrier communication apparatus 1B having such a configuration, the zero cross detection unit 211A is included in the coupling unit 21A, so that the power supply portion and the communication portion can be separated. For this reason, it becomes possible to employ | adopt as the power supply part 12 the power supply unit in which it is difficult to mount the zero cross detection part 11. FIG.

  In the example shown in FIG. 3, the zero cross detection unit 211A is connected to a series circuit of the coupling capacitor Cr and the primary side of the coupling transformer T1. For the commercial frequency, the impedance of the coupling capacitor Cr is high, while the impedance of the primary winding of the coupling transformer T1 is sufficiently low. For this reason, a current restricted by the impedance of the coupling capacitor Cr flows through the zero-cross detection unit 211A, and the zero-cross detection unit 211A detects the zero-cross using the current waveform of the commercial power source flowing through the coupling capacitor Cr. Therefore, since the drive current value of the zero-cross detection unit 211A can be determined not by the resistor element but by the capacitor Cr, the power consumption can be reduced by the amount of power consumed by the resistor element. In addition, in the case where the commercial power source is 100 V and 60 Hz, in order to flow a current of 10 mA to the input side of the photocoupler PC, the coupling capacitor Cr may be about 0.27 μF, and the impedance is about 100 kHz, for example. 5.9Ω, for example, about 0.3Ω at 2 MHz. Therefore, the coupling capacitor Cr is sufficient in terms of allowing the PLC communication signal to pass, whether it is a low-speed PLC or a high-speed PLC.

  Moreover, since the operation | movement regarding PLC is the same as that of 1 A of power line carrier communication apparatuses concerning 1st Embodiment demonstrated using FIG. 2, the description is abbreviate | omitted.

  Therefore, in the power line carrier communication apparatus 1B having such a configuration, an intermittent operation that repeats the operation state and the standby state is performed in accordance with the zero cross timing of the commercial power source detected by the zero cross detection unit 21A, and the PLC is operated in the operation state. Done. For this reason, the power line carrier communication apparatus 1B can perform PLC in synchronization with the other power line carrier communication apparatus 1B while achieving power saving.

  Moreover, in the power line carrier communication apparatus 1B of the present embodiment, the zero cross is counted (counted) as described above without configuring a clock unit that measures time such as date and time based on a pulse corresponding to the zero cross timing. However, since the count value of the zero cross and the time are not associated with each other and the start timing of the operation state is determined based on the pulse corresponding to the zero cross timing, the control process of the control unit 15 is performed in performing the intermittent operation. Can be simple.

  Next, another embodiment will be described.

(Third embodiment)
FIG. 4 is a diagram illustrating a configuration of a power line carrier communication apparatus according to the third embodiment. In FIG. 4, the power line carrier communication device 1C includes an impedance upper unit 10, a power source unit 12, a coupling unit 21B, a PLC unit 14, a control unit 15, an I / O unit 16, and a pair of electric circuits 17 (17a, 17b), and the coupling unit 21B includes a zero-cross detection unit 211B.

  In the power line carrier communication apparatus 1C according to the third embodiment, the zero cross detector 211B is different from the zero cross detector 211A in the power line carrier communication apparatus 1B according to the second embodiment.

  For this reason, the impedance upper unit 10, the power supply unit 12, the PLC unit 14, the control unit 15, and the I / O unit 16 in the power line carrier communication device 1 </ b> C are the impedance upper unit 10 in the power line carrier communication device 1 </ b> B of the second embodiment, Since it is the same as that of the power supply unit 12, the PLC unit 14, the control unit 15, and the I / O unit 16, the description thereof is omitted.

  The coupling unit 21B is a circuit that is connected to the pair of electric circuits 17 and extracts a PLC communication signal transmitted through the electric circuit 17, and superimposes the PLC communication signal on the electric circuit 17, and includes a zero-cross detection unit 211B. The coupling unit 21B includes, for example, a capacitor Cr, a coupling transformer T1 whose primary winding is connected in series with the coupling capacitor Cr, and a zero cross whose input side is connected in series to the primary winding, like the coupling unit 21A. And a detector 211B. The series connection circuit of the coupling capacitor Cr, the coupling transformer T1, and the zero-cross detection unit 211B is connected between the pair of input terminals, and is therefore connected between the pair of electric circuits 17.

  The zero cross detection unit 211B is a circuit that detects the zero cross timing of the commercial power supply and outputs a pulse in synchronization with the detected zero cross timing. The zero cross detection unit 211B outputs a pulse synchronized with the zero cross timing to the control unit 15. For example, the zero-cross detection unit 211B includes an AC input compatible photocoupler PC, a capacitor Cc provided between a pair of input terminals of the photocoupler PC (between an anode terminal and a cathode terminal), and an output side of the photocoupler PC. And a resistance element Rb connected in series. The capacitor Cc is connected in parallel to the two light emitting diodes LED1 and LED2 connected in antiparallel to each other of the photocoupler PC, has a sufficiently low impedance characteristic with respect to the frequency band of the PLC communication signal, and Has sufficiently high impedance characteristics for commercial frequencies. A power supply unit 12 is connected to the resistance element Rb, and a voltage is applied from the power supply unit 12 to the output side of the photocoupler PC via the resistance element Rb.

  In the power line carrier communication apparatus 1C having such a configuration, a capacitor Cc is provided between a pair of input terminals of the photocoupler PC in the zero cross detection unit 211B. For this reason, even when the commercial power supply is in the vicinity of 0 V and the photocoupler PC is to operate in the cutoff region, the PLC communication signal may be superimposed on the electric circuit 17 (the power line) via the capacitor Cc. It becomes possible. For this reason, even if the time of the operation state is set to a length including the zero cross of the commercial power supply, the PLC can be performed. Therefore, there is no restriction on the time setting of the operating state, and it becomes possible to transmit a PLC communication signal accommodating a relatively large size data.

  For example, when the light emitting diodes LED1 and LED2 are made of silicon, the cutoff region of the photodiode PC is in a range of about ± 0.7.

  Moreover, since the operation | movement regarding PLC is the same as that of 1 A of power line carrier communication apparatuses concerning 1st Embodiment demonstrated using FIG. 2, the description is abbreviate | omitted.

  Next, another embodiment will be described.

(Fourth embodiment)
FIG. 5 is a diagram illustrating a configuration of a power line carrier communication apparatus according to the fourth embodiment. 5, the power line carrier communication device 1C includes an impedance upper unit 10, a power source unit 12, a coupling unit 31, a PLC unit 14, a control unit 15, an I / O unit 16, and a pair of electric circuits 17 (17a, 17b), and the coupling unit 31 includes a zero-cross detection unit 311.

  In the power line carrier communication apparatus 1D according to the fourth embodiment, the coupling unit 31 and the zero cross detection unit 311 included therein are different from the coupling unit 21A and the zero cross detection unit 211A in the power line carrier communication apparatus 1B according to the second embodiment. .

  Therefore, the impedance upper unit 10, the power supply unit 12, the PLC unit 14, the control unit 15, and the I / O unit 16 in the power line carrier communication device 1 </ b> D are the impedance upper unit 10 in the power line carrier communication device 1 </ b> B of the second embodiment, Since it is the same as that of the power supply unit 12, the PLC unit 14, the control unit 15, and the I / O unit 16, the description thereof is omitted.

  The coupling unit 31 is connected to the pair of electric circuits 17 and extracts a PLC communication signal transmitted through the electric circuit 17 and superimposes the PLC communication signal on the electric circuit 17, and includes a zero-cross detection unit 311. The coupling unit 31 includes, for example, a coupling capacitor Cr having a sufficiently high impedance with respect to the commercial frequency of the commercial power source, and a primary winding connected in series with the coupling capacitor Cr, so that the communication signal component of the PLC is transmitted from the primary side. A coupling transformer T1 capable of transmitting to the secondary side and a zero-cross detection unit 311 having a pair of input terminals connected to both ends of the coupling capacitor Cr are configured. The series connection circuit of the coupling capacitor Cr and the coupling transformer T <b> 1 is connected between the pair of input terminals, and is therefore connected between the pair of electric paths 17. The PLC unit 14 is connected to the secondary side of the coupling transformer T1.

  The zero cross detection unit 311 is a circuit that detects the zero cross timing of the commercial power supply and outputs a pulse in synchronization with the detected zero cross timing. The zero cross detection unit 311 outputs a pulse synchronized with the zero cross timing to the control unit 15. The zero-cross detection unit 311 includes, for example, a resistance element Rc, a photocoupler PC corresponding to an AC input whose input side is connected in series to the resistance element Rc, and a resistance element Rb connected in series to the output side of the photocoupler PC. It is prepared for. A series connection circuit of the resistor element Rc and the photocoupler PC is connected in parallel to the coupling capacitor Cr. A power supply unit 12 is connected to the resistance element Rb, and a voltage is applied from the power supply unit 12 to the output side of the photocoupler PC via the resistance element Rb. The resistance element Rc is a current limiting resistor of the photocoupler PC.

  In the power line carrier communication apparatus 1D having such a configuration, the zero-cross detector 311 is connected to both ends of the coupling capacitor Cr. Since the coupling capacitor Cr has a larger impedance to the commercial frequency than the primary winding of the coupling transformer T1, the voltage of the commercial power supply is mainly applied to the coupling capacitor Cr. For this reason, the zero cross detection unit 311 connected to both ends of the coupling capacitor Cr can detect the zero cross timing of the commercial power source from the voltage waveform of the commercial power source applied to the coupling capacitor Cr.

  In addition, since the resistance element Rc of the zero cross detection unit 311 is a current limiting resistor of the photocoupler PC, a relatively large resistance value is usually used. For this reason, the current of the PLC mainly flows into the coupling capacitor Cr without almost flowing into the zero-cross detection unit 311. Therefore, the PLC communication signal is transmitted to the PLC unit 14 via the coupling transformer T1.

  In the power line carrier communication apparatus 1D having such a configuration, the zero cross detector 311 is connected to both ends of the coupling capacitor Cr, so that one is provided in the coupling part 31 as compared with the power line carrier communication apparatus 1C of the third embodiment. The capacitor Cr is sufficient. Therefore, the number of parts of the coupling portion 31 can be reduced accordingly, and the mounting area can be reduced accordingly.

  Moreover, since the operation | movement regarding PLC is the same as that of 1 A of power line carrier communication apparatuses concerning 1st Embodiment demonstrated using FIG. 2, the description is abbreviate | omitted.

  Next, another embodiment will be described.

(Fifth embodiment)
FIG. 6 is a diagram illustrating a configuration of a power line carrier communication apparatus according to the fifth embodiment. In FIG. 5, the power line carrier communication device 1E includes an impedance upper unit 10, a power source unit 12, a coupling unit 41, a PLC unit 14, a control unit 15, an I / O unit 16, and a pair of electric circuits 17 (17a, 17b), and the coupling unit 41 includes a zero-cross detection unit 411.

  In the power line carrier communication apparatus 1E according to the fifth embodiment, the coupling unit 41 is different from the coupling unit 31 in the power line carrier communication apparatus 1D according to the fourth embodiment.

  For this reason, the impedance upper unit 10, the power supply unit 12, the PLC unit 14, the control unit 15, and the I / O unit 16 in the power line carrier communication device 1 </ b> E are the impedance upper unit 10 in the power line carrier communication device 1 </ b> B of the second embodiment, Since it is the same as that of the power supply unit 12, the PLC unit 14, the control unit 15, and the I / O unit 16, the description thereof is omitted. Moreover, since the zero cross detection part 411 is the same as that of the zero cross detection part 311, the description is abbreviate | omitted.

  The coupling unit 41 is connected to the pair of electric circuits 17 and extracts a PLC communication signal transmitted through the electric circuit 17 and superimposes the PLC communication signal on the electric circuit 17, and includes a zero-cross detection unit 411. The coupling unit 41 has, for example, a four-winding configuration in which the primary side is the two windings n1a and n1b and the secondary side is the two windings n2a and n2b, and the PLC communication signal component is transmitted from the primary side to the secondary side. A coupling capacitor Cr provided between the coupling transformer T2 (T21, T22) capable of transmitting to the primary side and two windings on the primary side and having a sufficiently high impedance with respect to the commercial frequency of the commercial power source, and a coupling capacitor And a zero-cross detector 411 having a pair of input terminals connected to both ends of Cr. The coupling transformer T2 includes a transformer T21 configured to include a set of primary winding n1a and a secondary winding n1b, and a transformer configured to include a set of primary winding n2a and a secondary winding n2b. And T22. The primary winding n1a of the transformer T21, the coupling capacitor Cr, and the primary winding n2a of the transformer T22 are connected in series in this order, and this series connection circuit is connected between a pair of input terminals. Yes. For this reason, this series connection circuit is connected between the pair of electric paths 17. The PLC unit 14 is connected to the secondary side of the coupling transformer T2. That is, one end of the transformer T21 is connected to the PLC unit 14, the other end is grounded, and the other end of the transformer T22 is connected to the PLC unit 14, and one end thereof is grounded.

  In the power line carrier communication device 1E having such a configuration, the primary winding n1a of the transformer T21, the coupling capacitor Cr, and the primary winding n2a of the transformer T22 are connected in series in this order, and thus have a 4-winding configuration. The coupling transformer T2 has a symmetric configuration with respect to the pair of electric circuits 17 (the power lines) around the coupling capacitor Cr. For this reason, balanced transmission is possible, and noise resistance can be improved.

  Moreover, since the operation | movement regarding PLC is the same as that of 1 A of power line carrier communication apparatuses concerning 1st Embodiment demonstrated using FIG. 2, the description is abbreviate | omitted.

  In order to express the present invention, the present invention has been properly and fully described through the embodiments with reference to the drawings. However, those skilled in the art can easily change and / or improve the above-described embodiments. It should be recognized that this is possible. Therefore, unless the modifications or improvements implemented by those skilled in the art are at a level that departs from the scope of the claims recited in the claims, the modifications or improvements are not covered by the claims. To be construed as inclusive.

It is a figure which shows the structure of the power line carrier communication apparatus concerning 1st Embodiment. It is a time chart which shows operation | movement of the power line carrier communication apparatus concerning embodiment. It is a figure which shows the structure of the power line carrier communication apparatus concerning 2nd Embodiment. It is a figure which shows the structure of the power line carrier communication apparatus concerning 3rd Embodiment. It is a figure which shows the structure of the power line carrier communication apparatus concerning 4th Embodiment. It is a figure which shows the structure of the power line carrier communication apparatus concerning 5th Embodiment.

Explanation of symbols

1A to 1E Power line carrier communication device 10 Impedance upper part 11, 211A, 211B, 311 and 411 Zero cross detection part 12 Power supply part 13, 21A, 21B, 31, 41 Coupling part 14 Power line carrier communication part 15 Control part 16 Input output part C1, Cc Capacitor PC Photocoupler

Claims (6)

A pair of electrical paths for connecting to the power lines;
An impedance upper unit that is provided at a predetermined position on the pair of electric paths and has a low characteristic with respect to a commercial frequency and a high characteristic with respect to a frequency used for power line carrier communication;
A detection unit that is provided on the pair of electric paths and is located at a subsequent stage of the impedance upper unit, and detects a zero-cross timing of a commercial power source;
A capacitor provided between the pair of electrical paths between the impedance upper part and the detection part;
A power line carrier communication apparatus, comprising: a communication unit that is connected to the pair of electric paths, operates based on a zero cross timing detected by the detection unit, and performs the power line carrier communication. A pair of electrical paths for connecting to the power lines;
Taking out the communication signal of the power line carrier communication that transmits the electric path, and superimposing the communication signal of the power line carrier communication on the electric line,
A power line carrier communication unit that demodulates a communication signal of the power line carrier communication taken out by the coupling unit and modulates data into a communication signal of power line carrier communication and outputs the communication signal to the coupling unit;
The coupling unit includes a detection unit that detects a zero cross timing of a commercial power source,
The power line carrier communication unit operates based on a zero cross timing detected by the detection unit. The coupling unit has a coupling capacitor having a high impedance with respect to a commercial frequency and a primary winding connected in series with the coupling capacitor, and transmits a communication signal component of the power line carrier communication from the primary side to the secondary side. A coupling transformer that can
The power line carrier communication device according to claim 2, wherein the detection unit includes a photocoupler connected in series to the primary side of the coupling transformer and capable of receiving AC power. The power line carrier according to claim 3, wherein the detection unit includes a capacitor that is provided between a pair of input terminals of the photocoupler and has a low impedance with respect to a frequency used for the power line carrier communication. Communication device. The coupling unit has a coupling capacitor having a high impedance with respect to a commercial frequency and a primary winding connected in series with the coupling capacitor, and transmits a communication signal component of the power line carrier communication from the primary side to the secondary side. A coupling transformer that can
The detection unit includes a resistance element and a photocoupler connected in series with the resistance element and capable of inputting AC power, and the resistance element and the photocoupler connected in series are parallel to the coupling capacitor. The power line carrier communication device according to claim 2, wherein the power line carrier communication device is connected. The coupling unit has a four-winding configuration in which the primary side has two windings and the secondary side has two windings, and the communication signal component of the power line carrier communication can be transmitted from the primary side to the secondary side. A coupling transformer that can be provided, and a coupling capacitor that is provided between the two windings on the primary side and has a high impedance with respect to a commercial frequency;
The detection unit includes a resistance element and a photocoupler connected in series with the resistance element and capable of inputting AC power, and the resistance element and the photocoupler connected in series are parallel to the coupling capacitor. The power line carrier communication device according to claim 2, wherein the power line carrier communication device is connected.

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