JP5484248B2 - Cross frequency detection device - Google Patents

Description

  The present invention relates to a different frequency mixture detection device, a different frequency mixture detection method, and a different frequency mixture detection program, and more particularly to a different frequency mixture detection method in an AC feeder circuit of an electric railway passing through a different frequency power supply section.

  The commercial frequency of Japanese power companies is 60 Hz in the west and 50 Hz in the east, bordering on the Fuji River and Itoi River. For this reason, when the electric vehicle travels in both sections, an AC feeder circuit using a substation with a different commercial frequency as a power source is mixed, and a butt portion of feeders due to a different frequency power source is generated.

  If a short-circuit accident occurs due to flying objects or small animals at such a butt, incompatibility of different frequency power sources occurs. When mixing of 50 Hz and 60 Hz different frequency power sources occurs, a beat wave with a period of 100 ms with a large fluctuation in amplitude is generated, and an excessive current flows through the feeder, causing serious damage to electric vehicles and the like. It becomes like this.

  For this reason, when the contact of the different frequency power supply occurs, measures are taken such as quickly detecting this and shutting off the own post power supply.

  When 50 Hz and 60 Hz power supplies are mixed, the frequency of the beat wave is 55 Hz, which is an index for detecting different frequency mixing. The frequency can be detected by performing sampling and quantization and performing arithmetic processing based on the sampling theorem (Patent Document 1).

  In addition, as a method of detecting different frequency intrusion, a different frequency intrusion wave is separated into a 60 Hz component and a 50 Hz component by a bandpass filter having a center frequency of 50 Hz and a bandpass filter having a center frequency of 60 Hz, and There is a method of determining cross-frequency contact using a frequency component as an operating element and a frequency component of a local power supply as a suppressing element (Patent Document 2).

JP-A-9-56053 JP-A-63-93640

  However, in the method of detecting a beat wave having a frequency of 55 Hz, the amplitude is so strong that it is difficult to detect the frequency in a region where the current is small. For this reason, it is necessary to set the minimum operating current level to detect the frequency, and depending on the phase at the time of the accident, there is a problem that it takes 100 ms or more to detect the different frequency mixture, or the different frequency mixture detection time varies greatly. .

  In the method using the bandpass filter, since the frequency values of 50 Hz and 60 Hz are close to each other, the frequency component of the other power source passes through one of the bandpass filters, and an error may occur in the detection of the different frequency mixture.

  The present invention has been made in view of the above, and a different frequency mixing detection device and a different frequency mixing that can shorten the time for detecting different frequency mixing without reducing the accuracy of detecting different frequency mixing. An object is to obtain a detection method and a different frequency mixture detection program.

In order to solve the above-described problems and achieve the object, the different frequency infringement detection device of the present invention includes a first frequency component and a second frequency component included in the different frequency intrusion wave at a set single sampling frequency. The first frequency component is removed by calculating the difference between the AD conversion unit that performs sampling and the value sampled 0.5 cycles before the first frequency component or the value sampled one cycle before And calculating the difference between the sum of the first frequency component removing unit and the value sampled 0.5 cycles before the second frequency component or the value sampled one cycle before, Using both the sum of the second frequency component removal unit to be removed and the value of the first frequency component sampled 0.5 cycles before and the difference between the value sampled 1 cycle before The sum of the first sampling frequency doubling unit for doubling the sampling frequency of the first frequency component and the value sampled 0.5 cycles before the second frequency component and the value sampled 1 cycle before The second sampling frequency doubling unit for doubling the sampling frequency of the second frequency component using both of the difference between and the effective value of the output of the first sampling frequency doubling unit is a set threshold value A first signal that generates an ON signal when the ratio of the effective value of the output of the first sampling frequency doubling unit to the effective value of the output of the second sampling frequency doubling unit is larger than a set threshold value. The effective value of the output of the intrusion determination unit and the second sampling frequency doubling unit is larger than a set threshold value, and the effective value of the output of the first sampling frequency doubling unit is A second contact determination unit that emits an ON signal when the ratio of the effective value of the output of the second sampling frequency doubling unit is greater than a set threshold value, and the first contact determination unit and the second contact determination unit When an ON signal is output from both of the second contact determination sections, it is determined that the different frequency contact is present.

  According to the present invention, there is an effect that it is possible to shorten the time for detecting different frequency contact without reducing the accuracy of detecting different frequency contact.

FIG. 1 is a block diagram showing a schematic configuration of Embodiment 1 of an AC feeding device to which a different frequency mixture detection device according to the present invention is applied. FIG. 2 is a current waveform diagram showing an example of sampling points in the different frequency mixture detection method of FIG. FIG. 3 is a diagram showing a processing flow of the second embodiment of the different frequency mixture detection method according to the present invention. FIG. 4 is a diagram illustrating an example of a sampling method in the different frequency mixture detection method of FIG. FIG. 5 is a diagram showing a processing flow of the third embodiment of the sampling frequency doubling method according to the present invention. FIG. 6 is a diagram showing a flow of processing of the fourth embodiment of the transient state monitoring method in the different frequency mixture detection method according to the present invention. FIG. 7 is a block diagram showing a schematic configuration of the fifth embodiment of the different frequency mixture detection device according to the present invention. FIG. 8 is a block diagram showing a schematic configuration of the sixth embodiment of the different frequency mixture detection device according to the present invention.

  Hereinafter, embodiments of a different frequency mixture detection device according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. For example, in the following description, a case where a frequency component of 50 Hz and a frequency component of 60 Hz are included in the different frequency mixed wave is taken as an example, but the different frequency mixed wave including other frequency components is used. May be.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of Embodiment 1 of an AC feeding device to which a different frequency mixture detection device according to the present invention is applied. In FIG. 1, an AC power supply apparatus is provided with an AC power supply 101 having a power supply frequency of 50 Hz and an AC power supply 102 having a power supply frequency of 60 Hz adjacent to each other.

  Between the AC power supplies 101 and 102, trolley wires 103 and 104 for supplying electric power to the electric vehicle 110 for both 50 Hz and 60 Hz are connected. A trolley wire 103, 104 at an intermediate point between the AC power supplies 101, 102 is provided with a switching section 105 for switching the feeding section.

  The switching section 105 is provided with switching breakers 108 and 109 connected between two air sections 106 and 107 and trolley wires 103 and 104 sandwiching the air sections 106 and 107, respectively. And between each pole of the air sections 106 and 107 and the switching circuit breakers 108 and 109 is a different frequency power source butt portion of 50 Hz and 60 Hz.

In addition, this AC feeder is provided with a different frequency mixing detection device 100 for detecting different frequency mixing and is connected to the trolley wire 103 or 104 . Here, the different frequency mixing detection device 100 is provided with a sampling unit 100a and a mixing determination unit 100b.

  The sampling unit 100a samples the different frequency mixed wave at a single sampling frequency set so that a plurality of frequency components included in the different frequency mixed wave can be sampled. The contact determination unit 100b performs different frequency contact determination based on the comparison result of the frequency components sampled by the sampling unit 100a.

  When the electric vehicle 110 is traveling on the AC power supply 101 side section of the trolley line 103, the switching breaker 108 is on and 109 is off, and the electric vehicle 110 has an AC power of 50 Hz from the AC power supply 101. Is supplied.

  Next, when the electric vehicle 110 completely enters the intermediate section of the trolley wire 103, the switching breaker 108 is turned off and the switching breaker 109 is turned on. The electric vehicle 110 is supplied with 60 Hz AC power from the AC power source 102. Is done.

  Here, in the air sections 106 and 107, a short circuit accident due to flying objects or small animals may occur. In the switching breakers 108 and 109, a short circuit accident may occur due to a decrease in the withstand voltage between the electrodes. And when a short circuit arises in such a different frequency power supply butt | matching location, the accident of mixed contact of different frequency power supplies will occur.

  When contact between 50 Hz and 60 Hz different frequency power sources occurs, a beat-like different frequency contact wave with a period of 100 ms is generated and flows through the trolley wires 103 and 104. Then, the different frequency mixed wave that has flowed through the trolley wires 103 and 104 is sampled at a sampling frequency of 600 Hz by the sampling unit 100a.

Here, when a different frequency mixed wave including a frequency component of 50 Hz and a frequency component of 60 Hz is sampled at a sampling frequency of 600 Hz, values of 180 ° and 360 ° of the phase angle of the frequency component of 50 Hz are obtained, and 60 Hz A value of 180 ° and a value of 360 ° of the phase angle of the frequency component are obtained.

FIG. 2 is a current waveform diagram showing an example of sampling points in the different frequency mixture detection method of FIG. 2, the waveform _{V 1} and waveform _{V 2} of 60Hz of 50Hz is when incompatible, beat like different frequency incompatible wave _{V 3} of the periodic 100ms is generated.

Here, by setting the sampling frequency of the different frequency incompatible wave _{V 3} to 600 Hz, 12 sampling points _P 0 _{to P 12} for each phase 30 ° in one period in the waveform _{V 1} of the 50Hz is sampled.

Then, the value of 180 ° of the phase angle of the frequency component of 50Hz at the sampling point _{P 6} is obtained, the value of bets 360 ° of the phase angle of the frequency components of the sampling points _{P 12} In 50Hz is obtained. The obtained values of 180 ° of the phase angle of the frequency components of the sampling points _{P 5} in 60Hz, the value of bets 360 ° of the phase angle of the frequency components of the sampling points _{P 10} In 60Hz is obtained.

  1 calculates the sum of the 50 Hz frequency component sampled before 0.5 cycle or the difference between the sampled value before 1 cycle, thereby calculating the different frequency mixture. A frequency component of 50 Hz is removed from the wave, and a frequency component of 60 Hz is extracted.

  In addition, by calculating the sum of the frequency component of 60 Hz with the value sampled 0.5 cycles before or the difference with the value sampled 1 cycle before in the mixture determination unit 100b, 60 Hz from the different frequency mixture wave is calculated. Are removed, and a frequency component of 50 Hz is extracted.

  Then, the touch determination unit 100b determines whether the 50 Hz frequency component is mixed based on the ratio of the 50 Hz frequency component included in the different frequency mixed touch wave, and the 60 Hz frequency component is included in the different frequency mixed touch wave. It is determined whether a frequency component of 60 Hz is mixed based on the ratio.

  This eliminates the need to use a bandpass filter having a center frequency of 50 Hz and a bandpass filter having a center frequency of 60 Hz in order to separate the different frequency infringement waves into a frequency component of 50 Hz and a frequency component of 60 Hz. It is possible to improve the detection accuracy of different frequency mixing.

  Further, by extracting the frequency component of 50 Hz and the frequency component of 60 Hz from the different frequency mixed wave, it is not necessary to detect a beat wave having a frequency of 55 Hz. For this reason, it is not necessary to monitor the different frequency mixed wave over the beat wave period of 100 ms or more, and it becomes possible to detect the different frequency mixed wave in 100 ms or less. The damage can be prevented.

Embodiment 2. FIG.
FIG. 3 is a diagram showing a processing flow of the second embodiment of the different frequency mixture detection method according to the present invention. In FIG. 3, when currents having frequency components of 50 Hz and 60 Hz are mixed, the value of the 60 Hz component obtained by removing the 50 Hz component from the different frequency mixed wave and the value of the 50 Hz component obtained by removing the 60 Hz component are calculated.

  Then, if the ratio of 50Hz component and 60Hz component is included in the different frequency mixed wave using each value, it can be determined that there is a mixed accident when the frequency ratio of the power supply of other places is more than a certain value. It becomes.

For example, assuming that the effective value of the 60 Hz component extracted from the different frequency mixed wave is f _A and the effective value of the 50 Hz component extracted from the different frequency mixed wave is f _B , the frequency component of 60 Hz is satisfied when the following condition is satisfied. Can be determined to be included .

K _A1 <f _A and K _A <f _A / (f _A + f _B )
However, K _A1 and K _A are threshold values.

Moreover, when the following conditions are satisfied, it can be determined that a frequency component of 50 Hz is included .

K _B1 <f _B and K _B <f _B / (f _A + f _B )
However, K _B1 and K _B are threshold values.

  By performing the contact determination based on the ratio in which the 50 Hz component and the 60 Hz component are included in the different frequency mixed wave, it is possible to suppress a decrease in determination accuracy even when the amplitude of the different frequency mixed wave is small. For this reason, even when the strength of the amplitude of the different frequency touch wave is significant, it is possible to shorten the time for detecting the different frequency touch without reducing the detection accuracy of the different frequency touch.

FIG. 4 is a diagram illustrating an example of a sampling method in the different frequency mixture detection method of FIG. In FIG. 4, a circuit breaker 3 is provided between the own post power supply 1 and another post power supply 2. A transformer VT can be used when detecting a different frequency mixed wave as a voltage, and a current transformer CT can be used when detecting a different frequency mixed wave as a current.

  Then, after detecting the different frequency mixed wave as a current or voltage, the different frequency mixed wave is sampled and converted into a digital signal. Here, when 50 Hz and 60 Hz are mixed, the sampling frequency is determined so that data at the phase angles of 180 ° and 360 ° can be obtained simultaneously.

  In other words, if the sampling frequency of the different frequency mixed wave is set to 600 Hz (= 1.67 ms), the number of samplings n is 12 times for one cycle of 50 Hz, and the number of samplings n is 6 times for 0.5 cycles of 50 Hz. . Further, the sampling number n is 10 times for one cycle of 60 Hz, and the sampling number n is 5 times for 0.5 cycles of 60 Hz.

  When the AD-converted sampling value is obtained, the other frequency component is calculated by calculating the difference with the value one cycle (360 °) or the sum with the value 0.5 cycle (180 °) before Remove.

When the difference from the value before one cycle (360 °) of 50 Hz is calculated, the calculated value f ₁ is expressed by the following expression.
f ₁ = f (n) −f (n−12) = A ₁ sin (θ ₆₀ + 54 °)
However, _{A 1} is the amplitude of the waveform of 60 Hz, theta ₆₀ is the phase angle of the waveform of 60 Hz.

  For this reason, if the difference from the value before one period (360 °) of 50 Hz is calculated, the value of 50 Hz becomes 0, and it is possible to remove the 50 Hz component from the different frequency mixed wave, so the 60 Hz component is extracted. can do.

Further, when the difference from the value before one period (360 °) of 60 Hz is calculated, the calculated value f ₂ is represented by the following expression.
f ₂ = f (n) −f (n−10) = B ₁ sin (θ ₅₀ −60 °)
Where B ₁ is the amplitude of the ₅₀ Hz waveform, and θ ₅₀ is the phase angle of the ₅₀ Hz waveform.

  For this reason, if the difference from the previous 60 Hz period (360 °) is calculated, the 60 Hz value becomes 0, and it is possible to remove the 60 Hz component from the different frequency mixed wave, thus extracting the 50 Hz component. can do.

On the other hand, when the sum with the value before 0.5 period (180 °) of 50 Hz is calculated, the calculated value f ₃ is expressed by the following equation.
f ₃ = f (n) + f (n−6) = A ₂ sin (θ ₆₀ + 72 °)
However, _{A 2} is the amplitude of the waveform of 60 Hz, theta ₆₀ is the phase angle of the waveform of 60 Hz.

  For this reason, if the sum of the 50 Hz value before 0.5 period (180 °) is calculated, the 50 Hz value becomes 0, and it is possible to remove the 50 Hz component from the different frequency mixed wave. Can be extracted.

Also, when calculating the sum of the 0.5 cycle (180 °) before the value of 60 Hz, the calculated value _{f 4} is expressed by the following equation.
f ₄ = f (n) + f (n−5) = B ₂ sin (θ ₅₀ −75 °)
Where B ₂ is the amplitude of the waveform of 60 Hz, and θ ₅₀ is the phase angle of the waveform of ₅₀ Hz.

  Therefore, if the sum of the 60 Hz value before 0.5 period (180 °) is calculated, the 60 Hz value becomes 0, and it is possible to remove the 60 Hz component from the different frequency mixed wave. Can be extracted.

Embodiment 3 FIG.
FIG. 5 is a diagram showing a processing flow of the third embodiment of the sampling frequency doubling method according to the present invention. In FIG. 5, when the sampling frequency is 600 Hz and a 60 Hz component is extracted from the different frequency tactile wave, if the 60 Hz component is a sine wave (the peak value is constant), both of the calculated values f ₁ and f ₃ can be used. A sampling frequency that is twice the sampling frequency of 600 Hz (36 ° in terms of 60 Hz) can be realized. With 36 ° sampling, the value of 90 ° necessary for effective value calculation cannot be obtained, but with the 18 ° sampling, a value of 90 ° is obtained.

  In addition, when a 50 Hz component is extracted from a different frequency tactile wave with a sampling frequency of 600 Hz, if the 50 Hz component is a sine wave (the peak value is constant), sampling is twice the sampling frequency of 600 Hz (30 ° in terms of 50 Hz). The frequency can be realized. At this time, a value of 90 ° is obtained by 15 ° sampling, and an effective value can be calculated.

The effective value f ₅ calculated based on the calculated values f ₁ and f ₃ can be given by the following equation.
f ₅ = A ₃ sin θ ₆₀
However, _{A 3} is the amplitude of the waveform of 60 Hz, theta ₆₀ is the phase angle of the waveform of 60 Hz.

The effective value f ₆ calculated based on the calculated values f ₂ and f ₄ can be given by the following equation.
f ₆ = B ₃ sin θ ₅₀
Where B ₃ is the amplitude of the waveform of ₅₀ Hz, and θ ₅₀ is the phase angle of the waveform of ₅₀ Hz.

Embodiment 4 FIG.
FIG. 6 is a diagram showing a flow of processing of the fourth embodiment of the transient state monitoring method in the different frequency mixture detection method according to the present invention. In FIG. 6, the effective value f ₇ calculated based on the calculated value f ₁ can be given by the following equation.
f ₇ = A ₄ sin θ ₆₀
However, _{A 4} is the amplitude of the waveform of 60 Hz, theta ₆₀ is the phase angles of the waveform of 60 Hz.

Effective value f ₈ that the calculated value f ₃ is calculated on the original, can be given by the following equation.
f ₈ = A ₅ sin θ ₆₀
However, _{A 5} is the amplitude of the waveform of 60 Hz, theta ₆₀ is the phase angle of the waveform of 60 Hz.

Effective value f ₉ that the calculated value f ₂ is calculated on the original, can be given by the following equation.
f ₉ = B ₄ sin θ ₅₀
However, _{B 4} is the amplitude of the waveform of 50 Hz, the theta ₅₀ is the phase angle of the waveform of 50 Hz.

Calculated value f ₄ effective value f ₁₀ computed based on is given by the following equation.
f ₁₀ = B ₅ s inθ ₅₀
However, _{B 5} is an amplitude of the waveform of 50 Hz, the theta ₅₀ is the phase angle of the waveform of 50 Hz.

  For example, when the following conditions are satisfied, it can be determined that the different frequency mixed wave is not in a transient state, and malfunction of the mixed contact determination in a transient state can be prevented.

K ₁ <f ₇ / (f ₇ + f ₈ ) <K ₂ and K ₃ <f ₉ / (f ₉ + f ₁₀ ) <K _{4
However, K 1, K 2, K} 3, K 4 is a threshold.

Embodiment 5 FIG.
FIG. 7 is a block diagram showing a schematic configuration of the fifth embodiment of the different frequency mixture detection device according to the present invention. In FIG. 7, a feeder 12 is connected to the AC power source 11, and a breaker 13 is provided on the feeder 12.

  Then, the different frequency mixed wave flowing through the feeder 12 is detected as a voltage or a current by the transformer VT or the current transformer CT and input to the AD converter 15.

  Then, in the AD conversion unit 15, the different frequency tactile wave is sampled at a sampling frequency of 600 Hz, digitized, and input to the first frequency component removal unit 16 and the second frequency component removal unit 17.

The first frequency component removing unit 16 outputs a calculated value f ₁ obtained by removing the frequency 50 Hz component from the different frequency incompatibility wave by adding the sampling value every 0.5 cycle of 60 Hz, and every cycle of 60 Hz. the sampling value by subtraction operations, and outputs the calculated value f ₃ to remove the frequency 50Hz components from different frequency incompatible waves.

The second frequency component removing unit 17 adds a sampling value every 0.5 cycle of 50 Hz to output a calculation value f ₂ from which the frequency 60 Hz component is removed from the different frequency intertwined wave, and each cycle of 50 Hz. the sampling value by subtraction operations, and outputs the calculated value f ₄ obtained by removing the frequency 60Hz components from different frequency incompatible waves.

The sampling frequency doubling unit 18 uses the calculated values f ₁ and f ₃ to convert a sampling value of 36 Hz intervals of 60 Hz components into sampling values of 18 ° intervals, and doubles the sampling frequency of 60 Hz components. To do.

The sampling frequency doubling unit 19 uses the calculation values f ₂ and f ₄ to convert the sampling values of 30 Hz intervals of 50 Hz components into sampling values of 15 ° intervals, and double the sampling frequency of 50 Hz components. To do.

The effective value calculator 20 calculates an effective value f ₅ based on the calculated values f ₁ and f ₃ , calculates an effective value f ₇ based on the calculated value f ₁ , and calculates an effective value f ₃ based on the calculated value f _{3. 8} is calculated.

The effective value calculation unit 21 calculates an effective value f ₆ based on the calculated values f ₂ and f ₄ , calculates an effective value f ₉ based on the calculated value f ₂ , and calculates an effective value f based on the calculated value f _{4. 10} operations.

The mixture determination unit 22 issues an ON signal to the AND circuit 27 when the following conditions are satisfied.
K ₅₁ <f ₅ and K ₅ <f ₅ / (f ₅ + f ₆ )
_{However, K 5,} K ₅₁ is the threshold.

The mixture determination unit 23 issues an ON signal to the AND circuit 28 when the following conditions are satisfied.
K ₆₁ <f ₆ and K ₆ <f ₆ / (f ₅ + f ₆ )
However, K ₆ and K ₆₁ are threshold values.

The excessive state determination unit 25 monitors the ratio of the value obtained by extracting the 60 Hz component and the value obtained by extracting the 50 Hz component in order to prevent erroneous operation of the mixed contact determination in an excessive state. An ON signal is issued to the circuit 26. As the condition at this time, for example, the following expression can be used.
K ₁ <f ₇ / (f ₇ + f ₈ ) <K ₂ and K ₃ <f ₉ / (f ₉ + f ₁₀ ) <K ₄

In order to prevent erroneous operation of the contact determination due to noise, the noise determination unit 24 obtains the contact ratio of the 50 Hz component and the 60 Hz component, and issues an ON signal to the AND circuit 26 if it is equal to or greater than a certain value. As the condition at this time, for example, the following expression can be used.
K ₇ <f ₅ / (f ₅ + f ₆ ) and K ₈ <f ₆ / (f ₅ + f ₆ )
However, K ₇ and K ₈ are threshold values.

When it is determined that the different frequency mixed wave is not an excessive state and is not noise, the ON signal of the mixed contact determination unit 22 is input to the logical product circuit 29 via the logical product circuit 27, and the mixed contact determination unit 23. ON signal is input to the AND circuit 29 via the AND circuit 28.

  Then, when it is determined that the different frequency intertwining wave is not in an excessive state and is not noise, the relay 30 is operated when the ratio of the frequency components of the other power sources extracted from the different frequency intimate wave is a certain value or more. As a result, the circuit breaker 13 is operated and the feeder 12 is interrupted.

The first frequency component removing unit 16, the second frequency component removing unit 17, the sampling frequency doubling units 18, 19, the effective value calculating units 20, 21, the intrusion determining units 22, 23, the noise determining unit 24, the transient state The determination unit 25 and the AND circuits 26 to 29 may be realized by causing a computer to execute a different frequency mixture detection program.

Embodiment 6 FIG.
FIG. 8 is a block diagram showing a schematic configuration of the sixth embodiment of the different frequency mixture detection device according to the present invention. In FIG. 8, the cross frequency detection device includes a processor 51 including a CPU, a ROM 52 that stores fixed data, a RAM 53 that provides a work area to the processor 51, and mediation between a human and a computer. Human interface 54 for performing communication, communication interface 55 for providing means for communication with the outside, external storage device 56 for storing programs and various data for operating the processor 51, and AD converter 57 for converting different frequency mixed touch waves to digital values The processor 51, the ROM 52, the RAM 53, the human interface 54, the communication interface 55, the external storage device 56, and the AD conversion unit 57 are connected via a bus 58.

  As the external storage device 56, for example, a magnetic disk such as a hard disk, an optical disk such as a DVD, or a portable semiconductor storage device such as a USB memory or a memory card can be used. As the human interface 54, for example, a keyboard, a mouse, or a touch panel can be used as an input interface, and a display, a printer, or the like can be used as an output interface. As the communication interface 55, for example, a LAN card, a modem, a router, or the like for connecting to the Internet or a LAN can be used.

Here, the external storage device 56 is installed with a different frequency mixing detection program 56 a that causes the processor 51 to perform different frequency mixing detection processing. The different frequency mixture detection program 56a includes the first frequency component removal unit 16, the second frequency component removal unit 17, the sampling frequency doubling units 18 and 19, the effective value calculation units 20 and 21, and the mixture determination unit 22 shown in FIG. , 23, the noise determination unit 24, the transient state determination unit 25, and the AND circuits 26 to 29 can be realized on the processor 51.

  When the different frequency mixing detection program 56 a is started, the sampling values of the 50 Hz and 60 Hz different frequency mixing waves sampled by the AD converter 57 at a sampling frequency of 600 Hz are taken into the processor 51.

  Then, the processor 51 calculates the sum of the 50 Hz component sampled before 0.5 cycle or the difference from the sampled value before 1 cycle, thereby removing the 50 Hz component from the different frequency mixed wave. Is done.

  Further, the 60 Hz component is removed from the different frequency mixed wave by calculating the sum of the 60 Hz component sampled before 0.5 cycle or the difference from the value sampled one cycle before.

  Then, it is determined whether the 50 Hz component is mixed with the 50 Hz component based on the ratio included in the different frequency mixed wave, and whether the 60 Hz component is mixed based on the ratio included in the different frequency mixed wave is determined. Is done.

  When the different frequency mixture detection process is executed by a computer, it may be executed by a stand-alone computer, or may be distributed to a plurality of computers connected to a network, or executed by a cloud computer. You may make it make it.

  In the sixth embodiment of FIG. 8, the processor 51 has described the method of capturing the different frequency mixture detection program 56 a from the external storage device 56. However, the processor 51 loads the different frequency mixture detection program 56 a via the communication interface 55. May be.

  As described above, the different frequency intrusion detection apparatus according to the present invention can reduce the time of different frequency intrusion detection without reducing the detection accuracy of the different frequency intrusion, and the electric power passing through the different frequency power supply section can be achieved. It is suitable for a method of detecting different frequency interference in railway AC feeder circuits.

DESCRIPTION OF SYMBOLS 1 Own post power supply 2 Other post power supplies 3, 13 Circuit breaker 11, 101, 102 AC power supply 12 Feed line VT Transformer CT Current transformer 15, 57 AD conversion part 16 1st frequency component removal part 17 2nd frequency component removal part 18,19 sampling frequency doubling unit 20 and 21 the effective value calculating unit 22 Incompatible determination unit 24 noise judgment unit 25 transient state determining unit 26-29 logical Sekikai path 30 relay 51 processor 52 ROM
53 RAM
54 Human Interface 55 Communication Interface 56 External Storage Device 56a Different Frequency Interference Detection Program 58 Bus 100 Different Frequency Interference Detection Device 100a Sampling Unit 100b Interference Determination Unit 103, 104 Trolley Wire 105 Switching Section 106, 107 Air Section 108, 109 Switching Breaker 110 electric car

Claims (3)

An AD converter that performs sampling of the first frequency component and the second frequency component included in the different frequency infringement wave at the set single sampling frequency;
A first frequency component removing unit that calculates a sum of a value sampled 0.5 cycles before the first frequency component or a difference from a value sampled one cycle ago to remove the first frequency component; ,
A second frequency component removing unit that calculates a sum of a value sampled 0.5 cycles before the second frequency component or a difference from a value sampled one cycle before and removes the second frequency component; ,
A first frequency component doubling the sampling frequency of the first frequency component using both a sum of a value sampled 0.5 cycles before the first frequency component and a difference from a value sampled one cycle ago; A sampling frequency doubling unit;
First, the sampling frequency of the second frequency component is doubled using both the sum of the second frequency component and the value sampled one cycle before and the difference from the value sampled one cycle before. 2 sampling frequency doubling unit ,
The effective value of the output of the first sampling frequency doubling unit is larger than a set threshold value, and the effective value of the output of the first sampling frequency doubling unit with respect to the effective value of the output of the second sampling frequency doubling unit is A first incompatibility determining unit that issues an ON signal when the ratio of the values is greater than a set threshold;
The effective value of the output of the second sampling frequency doubling unit is larger than a set threshold, and the effective value of the output of the second sampling frequency doubling unit with respect to the effective value of the output of the first sampling frequency doubling unit is A second intrusion determining unit that issues an ON signal when the ratio of the values is greater than a set threshold;
With
A different frequency mixture detection device, wherein an ON signal is output from both of the first and second contact determination units, and determines that the different frequency mixture is present. Based on the difference between the sampled value to the sum and one cycle before the sampled value of 0.5 cycles prior to each frequency component, the transient state determining unit determines transient state of the different frequency incompatible wave The different frequency mixture detection device according to claim 1 , further comprising: A noise determination unit that determines noise of the different frequency mixed wave based on a sum of a value sampled 0.5 cycles before each frequency component and a difference from a value sampled 1 cycle before The different frequency mixture detection device according to claim 1 or 2, characterized by the above .

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