JP4710836B2 - Isolated operation detection device and synchronization method thereof - Google Patents

Description

  The present invention is, for example, disposed between a distributed power source using a power source generated by energy such as sunlight, liquid fuel or gas fuel, wind power, and hydropower, and a system power source such as a commercial power source. The present invention relates to an isolated operation detection device for detecting isolated operation of a distributed power source at a time and avoiding a failure caused by the isolated operation, and a synchronization method thereof.

  In recent years, in housing complexes and gathering areas where multiple companies have gathered, individual houses and businesses are equipped with distributed power sources such as solar power generation and fuel power generation so that they can be operated in parallel with system power sources such as shared commercial power sources. Reverse power flow (distribution of power) that connects to the grid and supplements the power consumed by the load with a distributed power source and supplies the power generated by the distributed power source to the system power when the power consumption of the load is low Power systems that perform are widely used.

  In such a power system in which a distributed power source and a system power source are interconnected, in the event of a system power failure in which the power supply is stopped due to a failure of the system power source, etc. When the operation is performed, when the system power supply is restored and power is supplied again, there is a possibility that an accident in a short-circuit state or other accidents may occur in the power system. Therefore, it is necessary to prevent the occurrence of an accident by detecting the isolated operation of the distributed power source. As a method to detect the isolated operation of the distributed power supply, to monitor the system voltage and detect the change that appears during the isolated operation in the event of a system power failure, and to vary the system voltage from the distributed power supply side There is an active method in which a disturbance signal is applied to detect a change that occurs during a single operation in the case of a system power failure. In particular, an active method for applying a disturbance signal that forcibly generates periodic minute fluctuations in reactive power of a distributed power source has been widely adopted.

  On the other hand, since each of the distributed power sources in the gathering area is interconnected via the power line of the shared system power source, there is mutual interference between disturbance signals applied to the system voltage from each distributed power source side. Occur. FIG. 8 is a general diagram showing the state of mutual interference between the disturbance signal A and the disturbance signal B applied to the two adjacent system voltages. In FIG. 8, a sine wave having a period of 500 ms indicated by a solid line is a disturbance signal A and a disturbance signal B, and a sine wave indicated by a dotted line is a combined signal of the disturbance signal A and the disturbance signal B due to mutual interference.

  FIG. 8A shows a case where the phase difference between the disturbance signal A and the disturbance signal B is zero. In this case, the amplitude of the synthesized signal is twice the amplitude of each disturbance signal. FIG. 8 (2) shows a case where the phase difference between the disturbance signal A and the disturbance signal B is 125 ms. In this case, the amplitude of the synthesized signal is slightly larger than the amplitude of each disturbance signal and is about twice the route. Become. FIG. 8 (3) shows a case where the phase difference between the disturbance signal A and the disturbance signal B is 167 ms. In this case, the amplitude of the synthesized signal is substantially the same as the amplitude of each disturbance signal. FIG. 8 (4) shows a case where the phase difference between the disturbance signal A and the disturbance signal B is 188 ms. In this case, the amplitude of the synthesized signal is slightly smaller than the amplitude of each disturbance signal and is about two minutes. It becomes 1 of. FIG. 8 (5) shows a case where the phase difference between the disturbance signal A and the disturbance signal B is 250 ms, that is, a case where the phase is opposite. In this case, the amplitude of the synthesized signal becomes zero.

  The mutual interference in the case of a plurality of disturbance signals applied to three or more system voltages is further complicated. When the phase difference of the disturbance signal applied to each of the plurality of system voltages is increased, the change applied to the system voltage is reduced, and when the phase difference of the disturbance signal is changed, the change applied to the system voltage is also unstable. As a result, it becomes difficult to detect the isolated operation of the distributed power source. Specifically, as shown in FIG. 8 (2), the phase difference between the disturbance signal A and the disturbance signal B is acceptable up to about 125 ms, but when the phase difference becomes 130 ms or more, the distributed power supply It becomes difficult to detect an isolated operation. For this reason, conventionally, a synchronization signal line for connecting a plurality of distributed power sources has been laid to establish synchronization between the isolated operation detection devices. However, the work of laying the synchronization signal line between the dwellings in an apartment house or the like is complicated, and there is a problem that the cost of laying work and maintenance is increased.

  In order to solve this problem, the applicant of the present application has disclosed the time information of AM radio broadcast radio waves transmitted from the outside, FM radio broadcast, in order to reduce the phase difference of disturbance signals applied to each of a plurality of system voltages. Receives time information of radio waves, time information of radio clock signals, time information of GPS signals, time information of television signals, etc., extracts a reference signal contained in the time information as an external synchronization signal, An invention has been proposed for an independent operation device or the like that synchronizes disturbance signals applied to each of a plurality of system voltages by a synchronization signal (see Patent Document 1).

  The configuration of Patent Document 1 includes a plurality of distributed power sources 3 that are interconnected to the system power source 2, and a plurality of isolated operation detection devices 10 that are arranged for each of the distributed power sources and detect an isolated operation. 1 is a grid interconnection system 1 that operates in parallel with a distributed power supply connected to a grid power supply, and each independent operation detection device detects a grid voltage for generating a grid signal synchronized with the phase of the grid voltage, A system monitoring unit 13 that detects system voltage, frequency, phase, and harmonics necessary for detecting isolated operation, and common signals such as AM radio broadcast radio waves, FM radio broadcast radio waves, radio clock signals, GPS signals, and TV signals An external synchronization signal receiving unit 16 that receives an external synchronization signal from the source 20, an internal synchronization signal generating unit 17 that generates an internal synchronization signal based on the system signal and the external synchronization signal, and a disturbance signal based on the internal synchronization signal To voltage A disturbance signal generating section 12 for pressurizing, detecting a disturbance signal in the system interconnection point X, on the basis of the detection result, so that with a single operation determination unit 14 determines the isolated operation. Therefore, according to the configuration of Patent Document 1, it is possible to establish synchronization between the isolated operation detection devices without laying a synchronization signal line.

  In particular, the radio clock signal is extracted as an external synchronization signal for synchronizing a disturbance signal applied to each of a plurality of system voltages, since only time information is transmitted, unlike a broadcast radio wave or a GPS signal radio wave. Convenient for An isolated operation prevention apparatus and method for extracting this radio clock signal as an external synchronization signal has also been proposed (see Patent Document 2).

  According to Patent Document 2, the grid interconnection power generator 20 includes a power failure determination processing unit 4 that executes a power failure determination process of the system power supply 30 by an active method, and a time signal generation unit 5 that generates an internal time signal T. Configured. The time signal generating means 5 can be realized by using an independent time signal generating device configured to include a radio timepiece that operates by receiving a standard radio wave.

  The radio clock signal is a signal obtained by modulating a carrier wave having a frequency of 40 kHz or 60 kHz with a time code. The time code has a structure in which one cycle is 60 seconds and three types of modulation signals are included. FIG. 9 is a diagram showing three types of pulse width modulation signals constituting the time code of the radio clock signal. As shown in FIGS. 9 (1) to (3), the three types of modulation signals are a 200 ms signal representing a “marker”, a 500 ms signal representing a binary “1”, and a binary “0”. Is composed of an 800 ms signal.

  FIG. 10 is a diagram showing a format of a radio clock signal for one cycle. As shown in FIG. 10, the radio clock signal has seven modulations of 0 seconds, 9 seconds, 19 seconds, 29 seconds, 39 seconds, 49 seconds, 59 seconds in 60 seconds from 0 seconds to 59 seconds. The signal is a marker of 200 ms, and “minute information”, “hour information”, “day information”, “year information”, “day information / leap information” are 500 ms “1” and “2” between two markers. It is represented by a combination of 8 modulated signals at 1 second intervals of 800 ms “0”. For example, 7-minute information of 8 bits from a 1-second modulation signal to an 8-second modulation signal is “40 minutes” for a 1-second modulation signal and “20 minutes” for a 2-second modulation signal. The second modulation signal is “10 minutes”, the 5 second modulation signal is “8 minutes”, the 6 second modulation signal is “4 minutes”, the 7 second modulation signal is “2 minutes”, and the 8 second modulation signal is “8 minutes”. The format is “1 minute”. Further, 6-bit time information of 9 bits from a 10-second modulation signal to an 18-second modulation signal includes 12-second modulation signal “20 o'clock”, 13-second modulation signal “10 o'clock”, 15 The second modulation signal is “8 o'clock”, the 16 second modulation signal is “4 o'clock”, the 17 second modulation signal is “2 o'clock”, and the 18 second modulation signal is “1 o'clock”.

For example, when the bits of the minute information and the hour information are “001 # 1001” and “## 01 # 0100” (# is a sign bit), (10 minutes) + (8 minutes) + (1 minute) = 19 Minute, (10 o'clock) + (4 o'clock) = 14:00, which represents the current time 14:19. The date information, year information, etc. are omitted, but in order to obtain the current accurate date, day of the week, and time, it is necessary to receive a 60-second modulated signal from 0 to 59 seconds in one cycle. There is. Therefore, the state of receiving radio waves normally must continue for 3 minutes or more.
JP 2006-262557 A (see abstract and FIG. 1) Japanese Patent Laying-Open No. 2005-210788 (see paragraph number 0020 and FIG. 1)

  When the radio clock signal is used to synchronize the disturbance signal in each isolated operation detection device, the reception timing, that is, the rising timing of the three types of modulation signals of the received radio clock signal is detected by the IC circuit, and 200 ms , 500 ms and 800 ms pulse signals. During this conversion, the rising timing of the modulation signal may not be detected due to the influence of noise. In particular, if the time interval from the falling timing of the previous modulation signal is short, the probability that the rising timing of the modulation signal cannot be detected increases. Therefore, the present applicant pays attention to the long time interval from the fall timing of the 200 ms modulation signal, and obtains a certain result by detecting the rise timing of the next modulation signal after the 200 ms modulation signal. I was able to.

  However, as shown in FIG. 10, only seven 200 ms modulation signals are included in the 60-second radio clock signal. Therefore, when the reception timing is first detected, there is a possibility that rapid detection may not be performed. . Further, when the modulation signal is converted into a pulse signal, a delay time is generated from the rise timing of the modulation signal to the rise timing of the pulse signal depending on the characteristics of the IC circuit. This delay time increases as the electric field strength of the radio clock signal decreases. For this reason, when the electric field strength of the radio clock signal is weak, the time width of the 200 ms modulation signal received for the delay time is further shortened, and normal detection may not be performed. As a result, it takes time to detect the reception timing for the first time, and during that time, it becomes impossible to establish the synchronization of disturbance signals between the isolated operation detection devices.

  Furthermore, in order to obtain the current accurate time information, the state in which the radio wave is normally received has to continue for 3 minutes or more, so the period until the time information is determined becomes longer. When there is a wave stop for several hours due to signal maintenance, etc., and the radio clock signal is restored after that, until the current time information is obtained, synchronization of disturbance signals between isolated operation detectors is quickly established. It becomes impossible to do. In particular, when the wave is stopped from December 31 to the next year, it is necessary to acquire all the information shown in FIG. 10, so the period until the time information is fixed becomes longer, and during that time, the individual operation is performed. It becomes impossible to establish the synchronization of the disturbance signal between the detection devices.

  Therefore, the present invention has been made in view of the above points, and an object of the present invention is to reduce the time until the reception timing is first detected even when the electric field strength of the radio clock signal is weak. An object of the present invention is to provide a stand-alone operation detection device and a synchronization method for a stand-alone operation detection device that can establish synchronization of disturbance signals between operation detection devices.

  In order to achieve the above object, the isolated operation detection device of the present invention comprises an external synchronization signal receiving means for receiving a radio wave transmitted from the outside and extracting a plurality of types of external synchronization signals contained in the radio wave. The external synchronization signal determining means for determining whether or not the external synchronization signal extracted by the external synchronization signal receiving means is of a specific type, and the specific type of external synchronization signal determined by the external synchronization signal determination means Disturbance signal generating means for generating a disturbance signal synchronized with the power supply voltage and applying it to the system voltage of the system power supply.

  Therefore, according to the isolated operation detection device of the present invention, even when the electric field strength of the radio clock signal is weak, the disturbance signal between the isolated operation detection devices is reduced by reducing the time until the reception timing is first detected. Synchronization can be established.

  In the isolated operation detection device of the present invention, the external synchronization signal determination means outputs other types of external synchronization signals in a period until the specific type of external synchronization signal is extracted by the external synchronization signal reception means. Temporarily determining, the disturbance signal generating means generates a disturbance signal synchronized with another type of external synchronization signal tentatively determined by the external synchronization signal determining means, and then the external synchronization signal determining means A disturbance signal synchronized with the determined specific type of external synchronization signal may be generated.

  Therefore, according to the isolated operation detection device of the present invention, when a reception timing is first detected, even if a specific type of external synchronization signal is not immediately extracted, another type of external synchronization signal that can be easily extracted is detected. By tentatively extracting, it is possible to establish the synchronization of disturbance signals between the isolated operation detectors so that the time until the reception timing is first detected can be shortened.

  In the isolated operation detection device of the present invention, the external synchronization signal receiving means extracts a 200 ms, 500 ms, and 800 ms external synchronization signal included in a radio clock signal transmitted from the outside, and the external synchronization signal determination means includes: In the period until the external synchronization signal of 200 ms is extracted by the external synchronization signal receiving means, the external synchronization signal of 800 ms may be tentatively determined.

  Therefore, according to the isolated operation detection apparatus of the present invention, when the reception timing is first detected, even if the 200 ms external synchronization signal is not immediately extracted, the 800 ms external synchronization signal that is easy to extract is provisionally extracted. By doing so, it is possible to establish the disturbance signal synchronization between the isolated operation detection devices so that the time until the reception timing is first detected can be shortened.

  In the isolated operation detection device of the present invention, the external synchronization signal receiving means extracts a plurality of types of external synchronization signals having different durations included in radio waves transmitted from the outside, and the external synchronization signal determination means includes: The extraction is performed by detecting the start timing of the external synchronization signal extracted by the external synchronization signal receiving means, and predicting the end timing of the extracted external synchronization signal based on the detected start timing. It may be determined whether the external synchronization signal is the specific type of external synchronization signal.

  Therefore, according to the isolated operation detection device of the present invention, even if the received radio clock signal includes cracks and unnecessary components, the specific operation used to establish the synchronization of disturbance signals between the isolated operation detection devices. It is possible to accurately determine the type of external synchronization signal.

  In the isolated operation detection device of the present invention, the external synchronization signal receiving means extracts a 200 ms, 500 ms, and 800 ms external synchronization signal included in a radio clock signal transmitted from the outside, and the external synchronization signal determination means includes: The start timing of the external sync signal extracted by the external sync signal receiving means is detected, and the end timing of the extracted external sync signal is 200 ms from the start timing based on the detected start timing. , 500 ms, or 800 ms may be predicted to determine whether the extracted external synchronization signal is the 200 ms external synchronization signal.

  Therefore, according to the isolated operation detection device of the present invention, even when the received radio clock signal includes cracks and unnecessary components, the 200 ms signal used to establish the disturbance signal synchronization between the isolated operation detection devices. The external synchronization signal can be accurately determined.

  In the isolated operation detection device of the present invention, the external synchronization signal determining means is reliable external synchronization based on a distribution of reception timings of a plurality of external synchronization signals extracted in a predetermined period by the external synchronization signal receiving means A signal reception timing may be specified, and the type of the external synchronization signal extracted by the external synchronization signal receiving unit may be determined in consideration of the specified reception timing as appropriate.

  Therefore, according to the isolated operation detection device of the present invention, even when the electric field strength of the radio clock signal fluctuates, synchronization of disturbance signals among a plurality of isolated operation detection devices can be established.

  In order to achieve the above object, a method for synchronizing an isolated operation detection device according to the present invention includes a first step of receiving a radio wave transmitted from outside and extracting an external synchronization signal included in the radio wave. A second step for determining whether or not the external synchronization signal extracted in the first step is of a specific type, and a synchronization with the specific type of external synchronization signal determined by the second step. And a third step of generating the disturbance signal and applying it to the system voltage of the system power supply.

  Therefore, according to the synchronization method of the isolated operation detection device of the present invention, even when the electric field strength of the radio clock signal is weak, the time until the reception timing is first detected is shortened, so that Disturbance signal synchronization can be established.

  In the synchronization method of the isolated operation detecting device of the present invention, the second step is a period of time until the specific type of external synchronization signal is extracted by the first step. Tentatively determined, and the third step is determined by the second step after generating a disturbance signal synchronized with another type of external synchronization signal tentatively determined by the second step. A disturbance signal synchronized with the specific type of external synchronization signal may be generated.

  Therefore, according to the synchronization method of the isolated operation detection device of the present invention, when a reception timing is first detected, even if a specific type of external synchronization signal is not immediately extracted, another type of external synchronization that is easy to extract is used. By temporarily extracting the synchronization signal, it is possible to establish the synchronization of the disturbance signal between the isolated operation detection devices so that the time until the reception timing is first detected can be shortened.

  In the synchronization method of the isolated operation detecting device of the present invention, the first step extracts an external synchronization signal of 200 ms, 500 ms, and 800 ms included in a radio clock signal transmitted from the outside, and the second step In the period until the 200 ms external synchronization signal is extracted in the first step, the 800 ms external synchronization signal may be tentatively determined.

  Therefore, according to the synchronization method of the isolated operation detection device of the present invention, when the reception timing is first detected, even if the 200 ms external synchronization signal is not immediately extracted, the 800 ms external synchronization signal that is easy to extract is provisionally set. By extracting automatically, it is possible to establish the synchronization of disturbance signals between the isolated operation detection devices so that the time until the reception timing is first detected can be shortened.

  In the synchronization method of the isolated operation detection device of the present invention, the first step extracts a plurality of types of external synchronization signals having different durations included in radio waves transmitted from the outside, and the second step includes The start timing of the external synchronization signal extracted by the first step is detected, and the extraction timing is predicted by predicting the end timing of the extracted external synchronization signal based on the detected start timing. It may be determined whether the external synchronization signal is the specific type of external synchronization signal.

  Therefore, according to the synchronization method of the isolated operation detection device of the present invention, in order to establish the synchronization of the disturbance signal between the isolated operation detection devices even when the received radio clock signal includes cracks and unnecessary components. The specific type of external synchronization signal to be used can be accurately determined.

  In the synchronization method of the isolated operation detection device of the present invention, the second step extracts an external synchronization signal of 200 ms, 500 ms, and 800 ms contained in a radio clock signal transmitted from the outside, and the second step Detects the start timing of the external synchronization signal extracted by the first step, and based on the detected start timing, the end timing of the extracted external synchronization signal is 200 ms from the start timing. , 500 ms, or 800 ms may be predicted to determine whether the extracted external synchronization signal is the 200 ms external synchronization signal.

  Therefore, according to the synchronization method of the isolated operation detection device of the present invention, in order to establish the synchronization of the disturbance signal between the isolated operation detection devices even when the received radio clock signal includes cracks and unnecessary components. The 200 ms type external synchronization signal to be used can be accurately determined.

  In the synchronization method of the isolated operation detection device of the present invention, the second step is an external device having reliability based on a distribution of reception timings of a plurality of external synchronization signals extracted in a predetermined period by the first step. The reception timing of the synchronization signal may be specified, and the type of the external synchronization signal extracted by the first step may be determined in consideration of the specified reception timing as appropriate.

  Therefore, according to the synchronization method of the isolated operation detection device of the present invention, it is possible to establish the synchronization of the disturbance signal among the multiple isolated operation detection devices even when the electric field strength of the radio clock signal varies.

  According to the isolated operation detection device of the present invention configured as described above, the external synchronization signal receiving means for receiving a radio wave transmitted from the outside and extracting a plurality of types of external synchronization signals included in the radio wave An external synchronization signal determining means for determining whether or not the external synchronization signal extracted by the external synchronization signal receiving means is of a specific type, and a specific type of external synchronization determined by the external synchronization signal determining means And a disturbance signal generating means for generating a disturbance signal synchronized with the signal and applying the disturbance signal to the system voltage of the system power supply. Thus, it is possible to establish the disturbance signal synchronization between the isolated operation detection devices so as to shorten the time until the detection.

  According to the synchronization method of the isolated operation detection device of the present invention configured as described above, the first step of receiving a radio wave transmitted from the outside and extracting an external synchronization signal included in the radio wave; A second step for determining whether the external synchronization signal extracted by the first step is of a specific type, and a synchronization with the specific type of external synchronization signal determined by the second step. A third step of generating a disturbance signal and applying the disturbance signal to the system voltage of the system power supply. Even when the electric field strength of the radio clock signal is weak, until the reception timing is first detected. Thus, it is possible to establish the synchronization of the disturbance signal between the isolated operation detecting devices so as to shorten the time.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment relating to an isolated operation detection device and a synchronization method thereof according to the present invention will be described based on the drawings. FIG. 1 is a block diagram showing an electric power system to which the isolated operation detection device according to the present embodiment is applied.

  A power system 1 shown in FIG. 1 includes a system power source 2 such as a commercial power source that supplies AC power having a frequency of 50 Hz, and a plurality of distributed power sources 3 (3A, 3B, 3C, ...) and a power conditioner (hereinafter abbreviated as "power converter") 4 (4A) connected to the distributed power source 3 and converting DC power into AC power having the same frequency as the system power source 2 and a set predetermined phase difference. 4B, 4C,...), AC power supplied from the power conditioner 4 and general load 5 (5A, 5B, 5C,...) That consumes AC power supplied from the system power supply 2, and each power conditioner 4 and system power supply. 2 and an isolated operation detection device 10 (10A, 10B, 10C,...) That detects the isolated operation of the distributed power supply 3 when the power of the system power supply 2 is stopped.

  Each individual operation detection device 10 includes a shutoff switch 11 that shuts off the power conditioner 4 and the system power source 2 and an AC supplied from the power conditioner 4 in order to stop the individual operation of the distributed power source 3 when the power of the system power source 2 is stopped. A disturbance signal generator 12 that generates a disturbance signal for changing the reactive power of the power, and monitors the system voltage at the grid connection point X, detects the influence of the applied disturbance signal, and outputs a disturbance detection signal In addition, based on the system monitoring unit 13 that outputs a system signal synchronized with the system voltage cycle and the disturbance detection signal output from the system monitoring unit 13, it is determined whether or not the system is operating independently. In some cases, an isolated operation determination unit 14 that outputs an isolated operation detection signal, an interconnection protection circuit 15 that shuts off the cutoff switch 11 in accordance with the isolated operation detection signal output from the isolated operation determination unit 14, A synchronization signal generation unit 16 that generates and outputs a signal, and a disturbance control signal for generating a disturbance signal based on the synchronization signal output from the synchronization signal generation unit 16 and the system signal output from the system monitoring unit 13 And a disturbance control unit 17 that outputs to the disturbance signal generation unit 12.

  FIG. 2 is a diagram showing signal waveforms at various parts in the isolated operation detection device of FIG. FIG. 2A shows a waveform of a system voltage of 50 Hz with a cycle of 20 ms. FIG. 2B is a system signal output from the system monitoring unit 13 to the disturbance control unit 17, and is a signal synchronized with the phase shifted by 90 degrees with respect to the waveform of the system voltage having a cycle of 20 ms. . FIG. 2C shows a synchronization signal output from the synchronization signal generator 16 to the disturbance controller 17. FIG. 2D shows a disturbance control signal generated in the disturbance control unit 17 based on the synchronization signal from the synchronization signal generation unit 16 and the system signal from the system monitoring unit 13. As shown in FIG. 2D, the disturbance control signal is a combination of high level (H) and low level (L) (HLHL) and (LHLH) every cycle 40 ms, which is twice the system voltage. Change. FIG. 2E shows a disturbance phase signal generated by the disturbance signal generation unit 12 based on the disturbance control signal from the disturbance control unit 17. As shown in FIG. 2E, the disturbance phase signal is at a high level when the disturbance control signal is (HLHL), and is at a low level when the disturbance control signal is (LHLH).

  FIG. 2F shows the phase state of the disturbance signal applied to the system voltage by the disturbance signal generator 12. As shown in FIGS. 2E and 2F, when the disturbance phase signal is at a high level, the disturbance signal in the advanced phase is applied to the system voltage, and the reactive power changes to the advanced phase side. On the other hand, when the disturbance phase signal is at a low level, the disturbance signal in the late phase is applied to the system voltage, and the reactive power changes to the late phase side. The system monitoring unit 13 detects the phase fluctuation of the reactive power, and detects the presence or absence of a power failure of the system power supply 2 based on the detected phase fluctuation and the set phase difference.

  FIG. 3 is a block diagram showing an internal configuration of the synchronization signal generator 16 shown in FIG. As shown in FIG. 3, the synchronization signal generator 16 includes a radio clock signal receiver 161, an edge detector 162, a counter 163 (hereinafter referred to as counter (a)), a counter 164 (hereinafter referred to as counter (b)), The determination unit 165, the signal selection unit 166, and the synchronization signal input unit 167 are included.

  The radio clock signal receiving unit 161 receives a radio clock signal (JJY) at an interval of 1000 ms (1 second) transmitted from the outside, and outputs a pulse of an external synchronization signal synchronized with the radio clock signal (this is a TCO: time code output). And output to the edge detection unit 162 and the signal selection unit 166.

  The edge detection unit 162 outputs the rising (starting) timing of the TCO pulse, that is, the reception timing, to the counter (a) and the determination unit 165, and determines the falling (ending) timing of the TCO pulse as the counter (b) and the determination. To the unit 165.

  The counter (a) repeatedly counts a 1 ms clock from 0 to 1000 for 1000 ms, that is, 1 second, and outputs the count value to the determination unit 165. The counter (a) becomes 0 at the moment when 1000 is counted.

  The counter (b) starts counting the clock of 1 ms from 0 according to the start signal from the determination unit 165, and 1000 or more clocks according to the reset signal from the determination unit 165 or 1 ms (here, It is reset to 0 when it counts.

  The determination unit 165 outputs a start signal to the counter (b) according to the count value of the counter (a) and the rising timing of the TCO pulse from the edge detection unit 162. The determination unit 165 also determines the type of TCO pulse based on the count value of the counter (b) and the rising timing of the TCO from the edge detection unit 162, and outputs a selection signal to the signal selection unit 166. Specifically, it is determined whether the TCO pulse corresponds to 200 ms, 500 ms, or 800 ms, and a selection signal is output to the signal selection unit 166. The determination unit 165 also determines the electric field strength of the radio clock signal according to the distribution of the count value from the counter (a), and selects the TCO when the electric field strength is equal to or greater than a predetermined value (here, 50 dB). When the radio clock signal is stopped or when the electric field strength of the radio clock signal is less than a predetermined value, 1000 counts of the counter (a) are output. A selection signal for selecting an up value, that is, a signal with an interval of 1000 ms (1 second) instead of the TCO is output to the signal selection unit 166.

  The signal selection unit 166 selects a TCO corresponding to 200 ms or 800 ms as an external synchronization signal according to the selection signal of the determination unit 165, or uses the 1000 count-up value of the counter (a) as an internal synchronization signal. The selected external synchronization signal or internal synchronization signal is output to the synchronization signal output unit 167.

  The synchronization signal output unit 167 outputs the external synchronization signal or the internal synchronization signal selected by the signal selection unit 166 to the disturbance control unit 17 as a synchronization signal.

  FIG. 4 is a diagram illustrating the operation of the determination unit 165 that measures the electric field strength based on the timing distribution of the radio clock signal. FIG. 4 (1) shows the relationship between the radio clock signal (JJY) and the count value of the counter (a). As described above, since the counter (a) counts the clock signal of 1 ms from 0 to 1000 in 1 second (1000 ms), the rising timing of the TCO corresponding to the reception timing of the radio clock signal is from 0 to 1000. Will match one of the count values. In FIG. 4A, the reception timing of the radio clock signal coincides with the count value 500 of the counter (a).

  FIG. 4 (2) shows the reception timing that varies according to the electric field strength of the radio clock signal. In the case of FIG. 4 (2), the reception timing of the radio clock signal varies from the count value 497 to 503 of the counter (a). The determination unit 165 detects the distribution of the number of radio clock signals for each count value (0 to 1000) of the counter (a) during a certain period. As the electric field strength of the radio clock signal increases, the number of distributed signals tends to increase. Therefore, by detecting the distribution of the number of radio clock signals, the electric field strength of the radio clock signals can be indirectly measured.

  FIG. 4 (3) is a diagram showing the distribution of the number of radio clock signals with respect to the count value of the counter (a) in a predetermined period. Experiments have shown that a radio clock signal having a count value of 30% or more distributed over the total number of radio clock signals in this period is reliable with an electric field strength of 50 dB. In the example of FIG. 7 (3), when the count value of the counter (a) is 499, 500, 501, the number of 30% or more is distributed. Therefore, the determination unit 165 sets the lower limit value 499 in the internal register n1 and sets the upper limit value 501 in the register n2.

  5 and 6 are flowcharts showing a synchronization method of the isolated operation detection device in the present embodiment. In the flowchart of FIG. 5, when the radio clock signal receiver 161 receives the radio clock signal (JJY), it outputs TCO (step S1). Since the edge portion 162 outputs the rising timing and falling timing of the TCO to the counter (a) and the counter (b), respectively, it is determined whether or not the rising timing of the TCO has been detected by the counter (a) (step). S2). When the TCO rising timing is detected by the counter (a), it is determined whether or not the count value of the 1 ms clock of the counter (a) is in the range from n1 (499) to n2 (501). (Step S3). If the TCO rising timing is not detected, or if the count value of the counter (a) when the TCO rising timing is detected is not within this range, a radio clock signal (JJY) is received in step S1. However, if the count value is within this range, a start signal is output to the counter (b) (step S4).

  Next, it is determined whether or not the TCO falling timing is detected by the counter (b) (step S5). When the falling timing of TCO is detected, the count value of the counter (b) at that time is determined. That is, it is determined whether or not the count value is in the range of 200 ms (in this case, 200 ms ± 10 ms) (step S6). If the count value is in the range of 200 ms, the register SIG of the determination unit 165 (initial value is 0). 1) is stored (step S7).

  When the TCO falling timing is not detected in the 200 ms range, or when the next TCO falling timing is detected after detecting the TCO falling timing in the 200 ms range, the counter (b) It is determined whether or not the count value is in the range of 500 ms (in this case, 500 ms ± 10 ms) (step S8). If it is in the range of 500 ms, 2 is stored in the SIG (step S9). At this time, if 1 is already stored in SIG, the value of SIG is updated to 2.

  When the TCO falling timing is not detected in the 500 ms range, or when the next TCO falling timing is detected after detecting the TCO falling timing in the 500 ms range, the counter (b) It is determined whether or not the count value is in the range of 800 ms (in this case, 800 ms ± 10 ms) (step S10). If it is in the range of 800 ms, 3 is stored in the SIG (step S11). At this time, if 1 or 2 is already stored in the SIG, the value of the SIG is updated to 3.

  After the value of 1, 2, or 3 is stored in the SIG, or when the value is not stored, it is determined whether or not the count value of the counter (b) has reached 999 in the flowchart of FIG. Step S12). That is, it is determined whether 1 second has elapsed since the counter (a) detected the rising timing of the TCO. If the count value does not reach 1000, it is determined in step S5 in FIG. 5 whether or not the TCO falling timing is detected. If the count value reaches 1000, the radio time signal at that time is determined. Since the normal falling timing of the TCO corresponding to has passed, it is determined whether the type of the radio clock signal is 200 ms, 500 ms, or 800 ms according to the value of SIG (step S13). Next, 0 is stored in SIG to prepare for determination of the next radio clock signal (step S14).

  After 0 is stored in SIG in step S14, or when the falling timing of TCO is not detected in step S5 in FIG. 5, the count value of the counter (b) is 1100 in step S15 in FIG. When the count value reaches 1100, the counter (b) is reset (step S16).

  FIG. 7 is a waveform diagram of signals in each unit of the synchronization generation unit 16 shown in FIG. FIG. 7A shows radio clock signals (J1, J2,...) Received by the radio clock signal receiving unit 161 every second. FIG. 7B shows TCO (time code output) output from the radio clock signal receiving unit 161 to the edge unit 162 and the signal selection unit 166 in response to the received radio clock signal. When the radio clock signal is affected by noise, cracks (▽ marks) and unnecessary components (* marks) occur in the TCO in FIG. The occurrence of such cracks and unnecessary components becomes more prominent as the electric field strength of the radio clock signal is weaker. FIG. 7C shows the count value of the 1 ms clock from 0 to 1000 in the counter (a). When the count value is in the range of n1 (499) to n2 (501), when the rising timing of the TCO is output from the edge part 162 to the counter (a), the determination part 165 sends a start signal to the counter (b). Output. FIG. 7D shows a count value of a 1 ms clock in the counter (b). FIG. 7E shows a determination result based on the count value of the counter (b) and the TCO falling timing from the edge portion 162.

  For example, the count value P1 of the counter (a) at the rise timing of the TCO in FIG. 7B corresponding to the J1 radio clock signal in FIG. 7A is n1 (499) in FIG. 7C. To n2 (501), the counter (b) counts a 1-ms clock from 0 as shown in FIG. If the TCO corresponding to the radio clock signal J1 is cracked during counting, the counter (b) in FIG. 7D is detected when the false fall timing due to the crack is detected. Since the count value Q1 is in the range of 200 ms, 1 is stored in the SIG. Next, when the falling timing of the TCO corresponding to the radio clock signal J1 is detected, the count value Q2 of the counter (b) is in the range of 800 ms in FIG. Update 1 stored in SIG to 3. Accordingly, the count value Q1 at the false fall timing in the radio clock signal J1 in FIG. 7A is canceled, and the radio clock signal J1 is detected in the determination result shown in FIG.

  Similarly, in the radio clock signals J2, J3, J4, and J5 in FIG. 7A, when the rising timing of the TCO is detected by the counter (a), the count of the 1 ms clock of the counter (a) at that time is counted. When the values are P2, P3, P4, and P5 in the range from n1 to n2 as shown in FIG. 7C, the counter (b) counts as shown in FIG. 7D. Start. When the normal falling timing of the TCO corresponding to the radio clock signals J2, J3, J4, and J5 and the false falling timing due to cracks and unnecessary components are detected, the count value of the counter (b) In the range of 200 ms, 500 ms, and 800 ms, in FIG. 7D, when the count value is Q3, Q4, Q5, Q6, Q7, Q8, SIG is 1, 2 (1 is updated), 1 2, 3 (update 2), store 2. Accordingly, the count values Q3 and Q6 at the false falling timing in the radio clock signals J2 and J4 in FIG. 7A are canceled, and the determination result shown in FIG. 7E shows that the radio clock signals J2, J3, J4 and J5 are detected.

  The TCO in FIG. 7B corresponding to the radio clock signal J6 in FIG. 7A cannot detect the rising timing of the TCO corresponding to the radio clock signal J6, as shown in FIG. 7C. . Therefore, when the count value of the counter (b) reaches 1100, the counter (b) is reset. After that, only the unnecessary component indicated by * is generated, and even if the rising timing of the unnecessary component is detected, the count value of the 1 ms clock of the counter (a) at that time is outside the range from n1 to n2. Therefore, the counter (b) is not started, and the reset state continues even after the 500 ms signal period of the radio clock signal J6 has passed. For this reason, the radio clock signal J6 is not detected in the determination result shown in FIG.

  In the TCO in FIG. 7B corresponding to the radio clock signal J7 in FIG. 7A, as shown in FIG. 7C, the rising timing of the TCO is detected at the count value P6, so the counter (b) Starts counting, and the falling timing of the TCO is detected with the count value Q9 in FIG. 7D, so the radio clock signal J7 is detected in the determination result shown in FIG.

  In the TCO in FIG. 7B corresponding to the radio clock signal J8 in FIG. 7A, as shown in FIG. 7C, the rising timing of the TCO is detected at the count value P6, so the counter (b) Starts counting, but due to cracks indicated by ▽ and unnecessary components indicated by *, the TCO falling timing can be detected in the range of 200 ms, 500 ms, and 800 ms as shown in FIG. 7D. Can not. For this reason, the radio clock signal J8 is not detected in the determination result shown in FIG.

  According to the present embodiment, the synchronization signal generation unit 16 of the isolated operation detection device 10 receives a radio wave transmitted from the outside, and three types of external synchronization of 200 ms, 500 ms, and 800 ms included in the radio wave. It has a radio clock signal receiving unit 161 that extracts a signal and a determination unit 165 that determines whether or not the external synchronization signal extracted by the radio clock signal reception unit 161 is 200 ms. When the electric field strength of the radio clock signal is weak because it has the disturbance control unit 17 and the disturbance signal generation unit 12 that generate a disturbance signal synchronized with the external synchronization signal of 200 ms and apply it to the system voltage of the system power supply 2 However, it is possible to establish disturbance signal synchronization between the isolated operation detection devices so that the time until the reception timing is first detected can be shortened.

  According to the present embodiment, the determination unit 165 tentatively determines the 800 ms external synchronization signal until the radio clock signal reception unit 161 extracts the 200 ms external synchronization signal, and the disturbance control unit. 17 and the disturbance signal generator 12 generate a disturbance signal synchronized with the 800 ms external synchronization signal tentatively determined by the determination unit 165, and then generate a disturbance synchronized with the 200 ms external synchronization signal determined by the determination unit 165. Since the signal is generated, when the reception timing is first detected, even if the 200 ms external synchronization signal is not immediately extracted, the 800 ms external synchronization signal that is easy to extract is provisionally extracted to receive the signal first. It is possible to establish disturbance signal synchronization between the isolated operation detection devices so that the time until timing is detected can be shortened.

  According to the present embodiment, the radio clock signal receiving unit 161 extracts the 200 ms, 500 ms, and 800 ms external synchronization signals included in the radio clock signal transmitted from the outside, and the determination unit 165 includes the radio clock signal. The rising timing of the external synchronization signal extracted by the receiving unit 161 is detected, and the falling timing of the extracted external synchronization signal is any of 200 ms, 500 ms, and 800 ms from the rising timing based on the detected rising timing. Therefore, it is determined whether or not the extracted external synchronization signal is a 200 ms external synchronization signal. Therefore, even if the received radio clock signal contains cracks or unnecessary components, the isolated operation is detected. The 200 ms external synchronization signal used to establish disturbance signal synchronization between devices is accurately It can be constant.

  According to the present embodiment, determination unit 165 receives a reliable external synchronization signal based on the distribution of reception timings of a plurality of external synchronization signals extracted in a predetermined period by radio clock signal reception unit 161. Since the timing is specified and the type of the external synchronization signal extracted by the radio clock signal receiving unit 161 is determined in consideration of the specified reception timing as appropriate, even if the electric field strength of the radio clock signal varies, a plurality of single synchronization signals are determined. The synchronization of disturbance signals between the operation detection devices can be established.

  In the present embodiment, the external synchronization receiving means described in the claims corresponds to the radio clock signal receiving section 161, the external synchronization signal determining means corresponds to the determining section 165, and the disturbance signal generating means corresponds to the disturbance control section 17 and the disturbance signal generating section 12, respectively. To do.

  In the present embodiment, the first step described in the claims is the operation of the radio clock signal receiving unit 161, the second step is the operation of the determination unit 165, and the third step is the disturbance control unit 17 and the generation of the disturbance signal. This corresponds to the operation of the unit 12.

  In the above embodiment, the present invention has been described by taking the case where a radio clock signal is used as an external synchronization signal as an example. However, a plurality of types of periodic signals included in radio broadcast radio waves and television broadcast radio waves have been described. It is also possible to use a plurality of types of periodic signals included in the signal or the GPS signal of the global positioning system as the external synchronization signal. For example, the main frame of the GPS signal is composed of 300-bit subframes transmitted every 6 seconds. Time information is included at the beginning of each subframe, the first transmission start after the satellite launch is set to 00 seconds per week, and the passage of real time is managed in weeks and seconds. The number of subframes transmitted in seconds can be recognized in advance. Therefore, the time information transmitted every 6 seconds can be received and the time information can be used as an external synchronization signal.

  In the above embodiment, the present invention has been described by taking the case where the synchronization signal generation unit 16 is configured by hardware as an example. However, the synchronization signal generation unit 16 is executed by a microcomputer such as a CPU (Central Processing Unit). In particular, the determination unit 165, the counter (a), the counter (b), and the signal selection unit 166 may be configured.

  According to the isolated operation detection device of the present invention, external synchronization signal receiving means for receiving a radio wave transmitted from the outside and extracting a plurality of types of external synchronization signals included in the radio wave, and receiving the external synchronization signal External synchronization signal determination means for determining whether or not the external synchronization signal extracted by the means is a specific type, and a disturbance signal synchronized with the specific type of external synchronization signal determined by the external synchronization signal determination means And a disturbance signal generating means for generating and applying to the system voltage of the system power supply, even when the electric field strength of the radio clock signal is weak, the time until the reception timing is detected first is obtained. It is possible to establish the disturbance signal synchronization between the isolated operation detection devices that can be shortened. Therefore, for example, it is useful for an electric power system that uses a plurality of single operation detection devices in a gathering area.

It is a block diagram which shows the electric power system to which the isolated operation detection apparatus in embodiment of this invention is applied. It is a figure which shows the signal waveform of each part in the isolated operation detection apparatus of FIG. It is a block diagram which shows the internal structure of the synchronizing signal generation part of FIG. In this Embodiment, it is a figure which shows the operation | movement which measures an electric field strength based on distribution of the reception timing of a radio timepiece signal. It is a flowchart which shows the synchronization method of the independent operation detection apparatus in this Embodiment. It is a flowchart which shows the synchronization method of the independent operation detection apparatus following FIG. It is a wave form diagram of the signal of each part in the synchronous signal generation part of FIG. It is a general figure which shows the mode of the mutual interference between the disturbance signals applied to the system voltage of two adjacent systems. It is a general figure which shows three types of modulation wave signals which comprise the time code | cord | chord of a radio time signal. It is a general figure which shows the format of the radio clock signal for 1 period.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric power system 2 System power supply 3 Distributed type power supply 4 Power conditioner 5 General load 10 Independent operation detection apparatus 11 Shut-off switch 12 Disturbance signal generation part (disturbance signal generation means)
13 System Monitoring Unit 14 Independent Operation Determination Unit 15 Interconnection Protection Circuit 16 Synchronization Signal Generation Unit 17 Disturbance Control Unit (Disturbance Signal Generation Unit)
161 Radio clock signal receiver (external synchronization signal receiver)
162 Edge detection unit 163 Counter (a)
164 Counter (b)
165 determination unit (external synchronization signal determination means)
166 Signal selection unit 167 Synchronization signal output unit

Claims (12)

An isolated operation detection that is arranged between a distributed power supply and a system power supply and detects the isolated operation of the distributed power supply when the power supply of the system power supply is stopped by a disturbance signal applied to the system voltage of the system power supply. A device,
External synchronization signal receiving means for receiving radio waves transmitted from the outside and extracting a plurality of types of external synchronization signals included in the radio waves;
External synchronization signal determining means for determining whether or not the external synchronization signal extracted by the external synchronization signal receiving means is of a specific type;
Disturbance signal generation means for generating a disturbance signal synchronized with a specific type of external synchronization signal determined by the external synchronization signal determination means and applying the disturbance signal to the system voltage of the system power supply. Driving detection device.   The external synchronization signal determining means tentatively determines another type of external synchronization signal in a period until the specific type of external synchronization signal is extracted by the external synchronization signal receiving means, and the disturbance signal The generation unit generates a disturbance signal synchronized with another type of external synchronization signal tentatively determined by the external synchronization signal determination unit, and then generates a specific type of external synchronization determined by the external synchronization signal determination unit. The isolated operation detection device according to claim 1, wherein a disturbance signal synchronized with the signal is generated.   The external synchronization signal receiving unit extracts an external synchronization signal of 200 ms, 500 ms, and 800 ms contained in a radio clock signal transmitted from the outside, and the external synchronization signal determination unit is operated by the external synchronization signal receiving unit. 3. The isolated operation detection device according to claim 2, wherein an 800 ms external synchronization signal is tentatively determined until a 200 ms external synchronization signal is extracted.   The external synchronization signal receiving means extracts a plurality of types of external synchronization signals having different durations contained in radio waves transmitted from outside, and the external synchronization signal determining means is extracted by the external synchronization signal receiving means. Detecting the start timing of the external synchronization signal and predicting the end timing of the extracted external synchronization signal based on the detected start timing so that the extracted external synchronization signal is the specific type. The isolated operation detection device according to claim 2, wherein it is determined whether the external synchronization signal is an external synchronization signal.   The external synchronization signal receiving means extracts a 200 ms, 500 ms, and 800 ms external synchronization signal included in a radio clock signal transmitted from the outside, and the external synchronization signal determination means is extracted by the external synchronization signal receiving means. The start timing of the external synchronization signal thus detected is detected, and the end timing of the extracted external synchronization signal is 200 ms, 500 ms, or 800 ms from the start timing based on the detected start timing The isolated operation detection device according to claim 4, wherein it is determined whether or not the extracted external synchronization signal is the 200 ms external synchronization signal.   The external synchronization signal determination means identifies the reception timing of the reliable external synchronization signal based on the distribution of the reception timings of the plurality of external synchronization signals extracted in a predetermined period by the external synchronization signal reception means, 2. The islanding operation detection device according to claim 1, wherein the type of the external synchronization signal extracted by the external synchronization signal receiving means is determined in consideration of the identified reception timing as appropriate. An isolated operation detection device that detects an isolated operation of the distributed power supply when the power supply of the system power supply is stopped between a distributed power supply and a system power supply by a disturbance signal applied to the system voltage of the system power supply. A synchronization method,
A first step of receiving a radio wave transmitted from the outside and extracting an external synchronization signal included in the radio wave;
A second step of determining whether or not the external synchronization signal extracted by the first step is of a specific type;
And a third step of generating a disturbance signal synchronized with the specific type of external synchronization signal determined by the second step and applying the disturbance signal to the system voltage of the system power supply. Method for synchronizing detection devices.   The second step tentatively determines another type of external synchronization signal during the period until the specific type of external synchronization signal is extracted by the first step, and the third step Generates a disturbance signal synchronized with another type of external synchronization signal tentatively determined by the second step and then synchronizes with the specific type of external synchronization signal determined by the second step 8. The method for synchronizing an isolated operation detection device according to claim 7, wherein a disturbance signal is generated.   In the first step, an external synchronization signal of 200 ms, 500 ms, and 800 ms included in a radio clock signal transmitted from the outside is extracted, and in the second step, the 200 ms external signal is extracted by the first step. 9. The synchronization method for an independent operation detection device according to claim 8, wherein an external synchronization signal of 800 ms is provisionally determined during a period until the synchronization signal is extracted.   The first step extracts a plurality of types of external synchronization signals having different durations included in radio waves transmitted from the outside, and the second step extracts the external synchronization signal extracted by the first step. By detecting the start timing of the signal and predicting the end timing of the extracted external synchronization signal based on the detected start timing, the extracted external synchronization signal becomes the specific type of external synchronization signal. It is determined whether it is a signal, The synchronizing method of the independent operation detection apparatus of Claim 7 characterized by the above-mentioned.   In the first step, an external synchronization signal of 200 ms, 500 ms, and 800 ms included in a radio clock signal transmitted from the outside is extracted, and in the second step, the external synchronization signal extracted by the first step is extracted. The start timing of the synchronization signal is detected, and based on the detected start timing, it is predicted whether the end timing of the extracted external synchronization signal is 200 ms, 500 ms, or 800 ms from the start timing. 11. The method for synchronizing an isolated operation detection device according to claim 10, wherein it is determined whether or not the extracted external synchronization signal is the 200 ms external synchronization signal. In the second step, the reception timing of the external synchronization signal having reliability is identified based on the distribution of the reception timings of the plurality of external synchronization signals extracted in the predetermined period by the first step, and the identification is performed. 8. The synchronization method for an isolated operation detecting device according to claim 7, wherein the type of the external synchronization signal extracted in the first step is determined in consideration of reception timing as appropriate.

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