JP2010058733A - Voltage measuring device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide voltage measuring device and method for preventing an abnormal voltage value known in advance from being measured. <P>SOLUTION: A power system drops AC voltage exceeding high voltage from a power system 1 via a railway substation 2 and supplies the AC voltage to a wire 4. The power system includes a voltage detecting part 271 for determining a voltage value of the power system 1, a just measured data storing part 272 for storing the voltage value determined by the voltage detecting part 271 by optional time, a threshold value deciding part 274 for deciding whether or not the voltage value determined by the voltage detecting part 271 exceeds the threshold value, an elapsed time detecting part 275 for detecting whether or not the voltage value passes for prescribed time when the threshold value deciding part 274 decides that the voltage value exceeds the threshold value, and a minimum voltage/maximum voltage detecting part 273 for detecting a maximum value/minimum value of voltage from the just measured data storing part 272 and the elapsed time detecting part 275. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a voltage measuring apparatus and a voltage measuring method capable of monitoring the voltage on the input side or the output side of an electric railway substation for a long period of time and monitoring the excess or deficiency of the voltage of the substation.

  Generally, a substation for electric railways is installed between a power transmission system and a train overhead line. This railway substation inputs a system voltage of a power transmission system and steps down an AC voltage to a voltage convenient for train operation. For this reason, a step-down transformer and a primary circuit breaker and a secondary circuit breaker are disposed on the primary side (input side) and secondary side (output side) of the step-down transformer, respectively, in the substation for electric railways. Yes.

  Conventionally, as a voltage measuring device in the power system of this railway substation, voltage detection means for converting the voltage of the power system into numerical data, and external triggers such as primary side breaker and secondary side breaker on / off And a suppression signal detection means for suppressing measurement due to a disturbance only when there is a trigger, and a maximum / minimum voltage detection means for detecting the minimum voltage / maximum voltage from the voltage detection means and the suppression signal detection means. In a situation where no suppression signal is received, an unnecessary voltage value is measured.

  As described above, the conventional voltage measuring device uses the circuit breaker on / off to prevent the minimum voltage from being measured. However, when there is no circuit breaker on / off signal, the transformer inrush current flows. In some cases, the abnormal voltage of the voltage when the three-phase unbalance is reached is erroneously measured, or the abnormal voltage associated with the abnormal operation of the train is sometimes measured. In the measurement of abnormal voltage, for example, in the event of an accident, there is a case where what the train should originally enter with notch off may enter with notch on, and at this time, the voltage may drop rapidly. In such a case, the voltage may be detected as the lowest voltage, and a voltage measuring device that can avoid detecting a voltage other than the lowest voltage that should be measured is desired.

  The minimum voltage that should be measured must be measured at the following points. That is, the train can move when the voltage is high, but when the voltage is low, the control devices in the train drive device cannot move. In particular, when there are several trains between substations, a voltage drop occurs according to the number of trains. This voltage drop prevents the train from moving. In order to eliminate this, the minimum voltage of the distribution system is measured.

  In Patent Document 1, the input signal at the time t2 when the signal is stabilized is held in the first analog memory as Vh1. Compared with the signal Vh1 in the subsequent period, Vh1 is held in the second analog memory if the difference is equal to or less than the threshold value. In this case, if the difference is greater than or equal to the threshold value, the second analog memory is not updated and noise is ignored. Subsequently, the sequence controller performs a reset retrigger and a remeasurement is performed.

  In Patent Document 2, the second wave height discriminator outputs a pulse during the time when the wave height exceeds the discrimination voltage and the wave height returns to the return voltage. When the time set by the delay circuit and the timer circuit is reached, a fixed pulse width is output, and the AND circuit discriminates between the signal pulse and the noise pulse.

  In Patent Document 3, the maximum value of the AC voltage is detected and recorded with respect to the half cycle of the AC voltage. The input voltage is applied to a comparator that receives a relatively low voltage Vr. When this voltage is exceeded, the comparator outputs a signal for enabling the maximum value detection circuit. Circuit DM1 samples the AC signal and maintains the sample at its output where the amplitude begins to decrease.

In Patent Document 4, as an example of a railway system for realizing energy saving, a substation for electric railways provides a predetermined upper limit value for output, and the output monitoring means constantly monitors the output, and the substation output is If the value exceeds the value, the control command means transmits a control command signal to the output control means, train group, operation management system, or some of them, and the received control command signal is output control or propulsion control or this It describes what restricts the output of the substation to a predetermined value or less by performing both controls. According to Patent Document 4, it is described that a temporary output peak of an electric railway substation can be suppressed, and the equipment capacity can be reduced.
Japanese Patent Laid-Open No. 7-191064 JP 2000-74968 4-500123 JP-A-5-24539

  The conventional voltage measuring device described above requires a trigger signal for turning on and off the circuit breaker, and it is difficult to prevent voltage measurement when the voltage falls.

  The present invention solves the above-described problems, and an object of the present invention is to provide a voltage measuring device and a voltage measuring method that do not measure an abnormal voltage value that is known in advance.

  In order to achieve the above object, an invention corresponding to claim 1 is a power supply system that steps down an AC voltage exceeding a high voltage from an electric power system via an electric railway substation and supplies it to an overhead line. A voltage detection unit for obtaining a current voltage value and temporarily storing the voltage value; a threshold value determination unit for determining whether the voltage value obtained by the voltage detection unit exceeds a threshold value; An elapsed time detecting means for detecting whether or not a predetermined time has elapsed when the threshold determining means determines that the threshold is exceeded, and the voltage detection It is determined whether or not the voltage value stored in the immediately preceding measurement data storage means is the maximum value or the minimum value up to the present time, and the immediately previous measurement data storage means for storing the voltage value temporarily stored by the means for an arbitrary time. Minimum voltage / When the large voltage detection means and the minimum voltage / maximum voltage detection means determine that the minimum voltage or the maximum voltage has been reached, the voltage value is output as the minimum voltage or the maximum voltage, and the minimum voltage / maximum voltage is output. When the voltage detection unit does not determine the minimum voltage or the maximum voltage up to the present time, the voltage measurement device includes a unit that updates the voltage value detected by the voltage detection unit to the immediately previous measurement data storage unit.

In order to achieve the above object, an invention corresponding to claim 2 is a power supply system that steps down an AC voltage exceeding a high voltage from a power system via a substation for electric railways and supplies the voltage to an overhead line. A voltage detection unit that obtains a current voltage value and temporarily stores the voltage value, a measurement data storage unit that stores a voltage value obtained by the voltage detection unit for an arbitrary time, and a voltage obtained by the voltage detection unit A first threshold value judging means for judging whether or not a value exceeds a first threshold value, a voltage value obtained by the voltage detecting means exceeds the first threshold value, and an alarm is issued. A second threshold value judging means for judging whether or not the second threshold value to be output is exceeded, and the first threshold value judging means judges that the first threshold value is exceeded Or the second threshold value judging means is a second threshold value. Effected even if it is determined that the value is greater than the elapsed time detecting means for time exceeds the respective threshold value to detect whether the predetermined time has elapsed,
Whether or not the voltage value temporarily stored in the voltage detection means is stored for an arbitrary time, and the voltage value stored in the immediately previous measurement data storage means is the maximum value or the minimum value up to the present. When the minimum voltage / maximum voltage detection means to be determined and the minimum voltage / maximum voltage detection means are determined to be the minimum voltage or the maximum voltage up to the present, this voltage value is output as the minimum voltage or the maximum voltage, If the minimum voltage / maximum voltage detection means does not determine the current minimum voltage or maximum voltage, a means for updating the voltage value detected by the voltage detection means and a detection by the minimum voltage / maximum voltage detection means A voltage provided with an alarm output means for determining whether the maximum value / minimum value of the measured voltage exceeds the second threshold value and issuing an alarm when the second threshold value is exceeded It is a measuring apparatus.

  In order to achieve the above object, an invention corresponding to claim 3 is a power supply system that steps down an AC voltage exceeding a high voltage from an electric power system via an electric railway substation and supplies it to an overhead line. Obtaining a current voltage value and temporarily storing it; a threshold value judging step for judging whether or not the voltage value obtained by the voltage detecting means exceeds a threshold value; An elapsed time detecting step for detecting whether a predetermined time has elapsed when the threshold value determining step exceeds a threshold value, and the voltage detection step It is determined whether or not the voltage value stored in the previous measurement data storage step is the maximum value or the minimum value up to the present time immediately before storing the voltage value temporarily stored in the process for an arbitrary time. Minimum voltage / If it is determined that the minimum voltage or the maximum voltage up to the present in the large voltage detection step and the minimum voltage / maximum voltage detection step, this voltage value is output as the minimum voltage or maximum voltage, and the minimum voltage / maximum voltage is output. And a step of updating the voltage value detected by the voltage detection means to the immediately previous measurement data storage means when the voltage detection means does not determine the minimum voltage or the maximum voltage up to the present.

In order to achieve the above object, an invention corresponding to claim 4 is a power supply system that steps down an AC voltage exceeding a high voltage from an electric power system via an electric railway substation and supplies it to an overhead line. A voltage detection step for obtaining the current voltage value and temporarily storing the voltage value, a measurement data storage step for storing the voltage value obtained in the voltage detection step for an arbitrary time, and a voltage obtained in the voltage detection step A first threshold value determining step for determining whether or not a value exceeds a first threshold value, a voltage value obtained in the voltage detecting step exceeds a first threshold value, and an alarm is issued. A second threshold value determining step for determining whether or not a second threshold value to be output is exceeded, and when the first threshold value determining step determines that the first threshold value is exceeded Or the second threshold value determining step is a second threshold value. Effected even if it is determined that the value is greater than the elapsed time detecting step of time that exceeds the respective threshold value to detect whether the predetermined time has elapsed,
Whether or not the voltage value stored in the immediately preceding measurement data storage step is the maximum value or the minimum value up to the present time immediately before storing the voltage value temporarily stored in the voltage detection step for an arbitrary time. When the minimum voltage / maximum voltage detection step to be determined and the minimum voltage / maximum voltage up to the present in the minimum voltage / maximum voltage detection step are determined, the voltage value is output as the minimum voltage or maximum voltage, If the minimum voltage / maximum voltage detection step is not determined to be the minimum voltage or the maximum voltage up to the present, the voltage value detected in the voltage detection step is updated, and the minimum voltage / maximum voltage detection step is detected. And a warning output step for determining whether or not the maximum / minimum value of the measured voltage exceeds the second threshold value and issuing an alarm when the second threshold value is exceeded It is a measurement method.

  According to the present invention, a voltage measuring device capable of measuring the minimum / maximum voltage of a system without being influenced by the up and down of the voltage, which is caused by operating the system equipment at the time of rising or falling of the voltage. And a voltage measurement method can be provided.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram for explaining a railway substation to which the present invention is applied. The railway substation 2 is installed between the power transmission system 1 and the overhead line 4 of the train 3. The railway substation 2 receives the system voltage of the power transmission system 1 and steps down the AC voltage to a voltage convenient for train operation. For this reason, a step-down transformer 21 and a primary-side circuit breaker 22 and a secondary-side circuit breaker 23 are provided on the primary side (input side) and secondary side (output side) of the step-down transformer 21 in the railway substation, respectively. It is arranged. Then, instrument transformers 24, 25, and 26 for measuring the voltage on the primary side and the secondary side of the transformer 21, and the instrument variable for measuring the current on the primary side and the secondary side of the transformer 21. Flowers 28, 29, 30 are provided. Furthermore, voltage measuring devices 27 and 20 of the present invention are provided.

FIG. 2 is a block diagram for explaining 27 of the voltage measuring devices 27 and 20 of FIG. 1. Since 20 has the same configuration as 27, only 27 will be explained here. That is,
A voltage that lowers the AC voltage exceeding the high voltage from the power system 1 via the railway substation 2 and supplies it to the overhead line 4, obtains the voltage value of the power system 1, and temporarily stores this voltage Detecting means such as a voltage detecting unit 271 and immediately preceding measurement data storing means for storing voltage values temporarily stored in the voltage detecting unit 271 for an arbitrary time, such as immediately preceding measured data storing unit 272 and immediately preceding measured data storing unit 272 Minimum voltage / maximum voltage detection means for determining whether the measured voltage value is the maximum value or the minimum value up to the present, for example, the minimum voltage / maximum voltage detection unit 273 and the minimum voltage / maximum voltage detection unit 273 When the voltage or the maximum voltage is determined, the voltage value is output as the minimum voltage or the maximum voltage, and the minimum voltage / maximum voltage detection unit 273 outputs the minimum voltage up to the present time. Pressure or if it is not determined that the maximum voltage is obtained by a means for updating the voltage values detected by the voltage detection unit 271, immediately before the measurement data storage unit 272.
FIG. 3 is a diagram for explaining the above-described threshold value and a predetermined time (arbitrary time). The threshold is, for example, 10% of the rated voltage, and the predetermined time is a time for excluding the transient phenomenon. Among these, t1 is, for example, 5 seconds at the average maximum, and t2 is, for example, 2 seconds at the average maximum. In FIG. 3, the maximum / minimum measurement range indicates the range to be measured of the present invention excluding the transient phenomenon.

FIG. 4 is a flowchart for explaining the operation of FIG. 2. In the power supply system that reduces the AC voltage exceeding the high voltage from the power system through the substation for electric railway and supplies it to the overhead line,
This is a method of detecting the system voltage and measuring the minimum / maximum value of the detection voltage by the detection value exceeding a threshold and elapses or goes back a predetermined time.

Specifically, the system voltage is measured and buffered (S1), and it is determined whether the measured voltage exceeds a threshold value (S2). In S2, it is determined that the threshold value has been exceeded, and it is determined whether or not a predetermined time has passed since the threshold value was exceeded (S3). In S3
When it is determined that the predetermined time has passed the time exceeding the threshold, the measured value of the system voltage is stored in the immediately preceding measurement data storage unit 272 (S6). When it is determined in S3 that the predetermined time has not elapsed after the threshold value is exceeded, the measured value of the system voltage is discarded (S4) and the process ends (S5).

  Then, it is determined whether the voltage value stored in S6 is the maximum value (MAX) or the minimum value (MIN) is within the maximum value or the minimum value (S7). In S7, if the stored voltage value exceeds the maximum value stored so far or does not exceed the minimum value, the value stored in S6 is updated (S8), and the process returns to S6 again. If the stored voltage value is within the maximum value or the minimum value stored so far in S7, the value stored in S6 is output (S9).

  As a result, when the system voltage rises or falls, the power system breaker is turned on and off, regardless of whether the system voltage is up or down, and even if the train driver performs abnormal operation. The minimum / maximum voltage of the power system can be measured.

  FIG. 5 is a block diagram for explaining a second embodiment different from the above-described embodiment. That is, the current voltage value of the electric power system 1 is obtained in a power supply system that steps down the AC voltage exceeding the high voltage from the electric power system 1 via the electric railway substation 2 and supplies it to the overhead line. Voltage detection means to be stored, for example, voltage detection unit 271 and voltage data obtained by voltage measurement unit 271 immediately before measurement data storage means for storing the voltage value obtained by voltage detection unit 271 for an arbitrary time, for example, voltage obtained by voltage detection unit 271 The first threshold value determining means for determining whether the value exceeds the first threshold value, for example, the threshold value 1 determining unit 274 and the voltage value obtained by the voltage detecting unit 271 are the first threshold value. The second threshold value judging means for judging whether the threshold value is exceeded and the second threshold value for warning is exceeded, for example, the threshold value 2 judging unit 276 and the threshold value 1 judging unit 274 are 1 threshold exceeded Or when the threshold value 2 determination unit 276 determines that the second threshold value has been exceeded, a time that exceeds each threshold value has elapsed for a predetermined time. An elapsed time detecting means for detecting whether or not there is, for example, an elapsed time detecting section 275, a previous measurement data storage means for storing the voltage value temporarily stored in the voltage detecting section 271 for an arbitrary time, for example, a previous measured data storage section 272, Minimum voltage / maximum voltage detection means for determining whether the voltage value stored in the immediately previous measurement data storage unit 272 is the maximum value or the minimum value up to the present, for example, the minimum voltage / maximum voltage detection unit 273, and the minimum voltage / maximum voltage When the detection unit 273 determines that the minimum voltage or the maximum voltage has been reached, the voltage value is output as the minimum voltage or the maximum voltage, and the minimum voltage / maximum voltage detection unit 27 If the voltage is not determined to be the minimum voltage or the maximum voltage up to now, the means for updating the voltage value detected by the voltage detection unit 271 and the maximum value / minimum value of the voltage detected by the minimum voltage / maximum voltage detection unit 253 are An alarm output means for determining whether or not the second threshold value is exceeded and issuing an alarm when the second threshold value is exceeded, for example, an alarm output unit 277 is provided. As the alarm output unit 277, for example, a data logger is used.

  FIG. 7 is a flowchart for explaining the operation of FIG. 5. In the embodiment described above, an alarm is output when the measured value of the system voltage changes extremely, specifically, step S10, S11 is added, and step S2 is changed to S2A. That is, it is determined whether or not the maximum value / minimum value of the voltage detected by the voltage detection unit 253 in step S2A exceeds the first threshold value or exceeds the second threshold value. In step S10, it is determined whether the maximum value / minimum value of the voltage updated in S8 exceeds the threshold value 2. In step S11, an alarm (alarm) is issued when it is determined in step S10 that the maximum value / minimum value of the voltage has exceeded the threshold value 2. Except this point, the present embodiment is the same as the above-described embodiment.

  By configuring as shown in FIG. 5 and FIG. 7, it is possible to notify the abnormal state of the system voltage, whereby measures can be taken as soon as possible, and the operation stop time of the train can be shortened.

The block diagram for demonstrating the electric power feeding system containing the substation for railways to which the voltage measuring device of this invention is applied. The block diagram which shows 1st Embodiment of the voltage measuring device of this invention. FIG. 3 is a waveform diagram for explaining a maximum / minimum measurement range including a threshold value and an elapsed time in FIG. 2. The flowchart for demonstrating operation | movement of 1st Embodiment of the voltage measuring device of this invention. The block diagram which shows 2nd Embodiment of the voltage measuring device of this invention. FIG. 6 is a waveform diagram for explaining a maximum / minimum measurement range including a threshold value and an elapsed time of FIG. 5. The flowchart for demonstrating operation | movement of 2nd Embodiment of the voltage measuring device of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electric power system, 2 ... Electric railway substation, 3 ... Electric train, 4 ... Overhead wire, 21 ... Step-down transformer, 22 ... Primary side circuit breaker, 23 ... Secondary side circuit breaker, 24, 25 ... Instrument transformer, 27, 20 ... voltage measuring device, 28, 29 ... instrument current transformer, 271 ... voltage detector, 272 ... immediately preceding measurement data storage unit, 273 ... maximum voltage detector, 274 ... threshold determination unit, 275 ... progress Time detector.

Claims (4)

In the power supply system that reduces the AC voltage exceeding the high voltage from the power system via the substation for railways and supplies it to the overhead line,
Voltage detection means for obtaining a current voltage value of the power system and temporarily storing the voltage value;
Threshold value determination means for determining whether or not the voltage value obtained by the voltage detection means exceeds a threshold value;
Elapsed time detection means for detecting whether a predetermined time has elapsed when the threshold determination means determines that the threshold has been exceeded, and
Immediately before measurement data storage means for storing the voltage value temporarily stored in the voltage detection means for an arbitrary time;
Minimum voltage / maximum voltage detection means for determining whether the voltage value stored in the immediately preceding measurement data storage means is the maximum value or the minimum value up to now;
When the minimum voltage / maximum voltage detecting means determines that the minimum voltage or the maximum voltage up to the present is reached, the voltage value is output as the minimum voltage or the maximum voltage, and the minimum voltage / maximum voltage detecting means up to the present time. Means for updating the voltage value detected by the voltage detection means to the immediately preceding measurement data storage means if not determined to be the minimum voltage or the maximum voltage of
A voltage measuring device comprising: In the power supply system that reduces the AC voltage exceeding the high voltage from the power system via the substation for railways and supplies it to the overhead line,
Voltage detection means for obtaining a current voltage value of the power system and temporarily storing the voltage value;
Immediately before measurement data storage means for storing the voltage value obtained by the voltage detection means for an arbitrary time;
First threshold value determining means for determining whether or not the voltage value obtained by the voltage detecting means exceeds a first threshold value;
Second threshold value determining means for determining whether the voltage value obtained by the voltage detecting means exceeds a first threshold value and exceeds a second threshold value for issuing an alarm;
When the first threshold value determining unit determines that the first threshold value is exceeded, or the second threshold value determining unit determines that the second threshold value is exceeded An elapsed time detecting means for detecting whether a predetermined time has elapsed when the time exceeding each of the thresholds is exceeded,
Immediately before measurement data storage means for storing the voltage value temporarily stored in the voltage detection means for an arbitrary time;
Minimum voltage / maximum voltage detection means for determining whether the voltage value stored in the immediately preceding measurement data storage means is the maximum value or the minimum value up to now;
When the minimum voltage / maximum voltage detecting means determines that the minimum voltage or the maximum voltage up to the present is reached, the voltage value is output as the minimum voltage or the maximum voltage, and the minimum voltage / maximum voltage detecting means up to the present time. Means for updating to the voltage value detected by the voltage detecting means when it is not determined that the minimum voltage or the maximum voltage,
An alarm for determining whether or not the maximum value / minimum value of the voltage detected by the minimum voltage / maximum voltage detecting means exceeds a second threshold value, and issuing an alarm when the second threshold value is exceeded. Output means;
A voltage measuring device comprising: In the power supply system that reduces the AC voltage exceeding the high voltage from the power system via the substation for railways and supplies it to the overhead line,
Obtaining a current voltage value of the power system, and temporarily storing this voltage detection step;
A threshold value determining step for determining whether or not the voltage value obtained by the voltage detecting means exceeds a threshold value;
An elapsed time detecting step for detecting whether or not a predetermined time has elapsed when the threshold value determining step exceeds a threshold value; and
A measurement data storage step immediately before storing the voltage value temporarily stored in the voltage detection step for an arbitrary time,
A minimum voltage / maximum voltage detection step for determining whether the voltage value stored in the immediately previous measurement data storage step is the maximum value or the minimum value up to the present;
If it is determined that the minimum voltage or the maximum voltage up to the present in the minimum voltage / maximum voltage detection step, this voltage value is output as the minimum voltage or the maximum voltage, and the minimum voltage / maximum voltage detection means up to the present The voltage value detected by the voltage detection means if it is not determined as the minimum voltage or the maximum voltage, updating the previous measurement data storage means,
A voltage measuring method characterized by comprising: In the power supply system that reduces the AC voltage exceeding the high voltage from the power system via the substation for railways and supplies it to the overhead line,
Obtaining a current voltage value of the power system, and temporarily storing this voltage detection step;
A measurement data storage step immediately before storing the voltage value obtained in the voltage detection step for an arbitrary time;
A first threshold value determining step for determining whether or not the voltage value obtained in the voltage detecting step exceeds a first threshold value;
A second threshold value determining step for determining whether or not the voltage value obtained in the voltage detecting step exceeds a first threshold value and exceeds a second threshold value for issuing an alarm;
When the first threshold value determining step determines that the first threshold value has been exceeded, or the second threshold value determining step is determined to have exceeded the second threshold value An elapsed time detecting step for detecting whether a predetermined time has elapsed when the time exceeding each of the threshold values has passed,
A measurement data storage step immediately before storing the voltage value temporarily stored in the voltage detection step for an arbitrary time,
A minimum voltage / maximum voltage detection step for determining whether the voltage value stored in the immediately previous measurement data storage step is the maximum value or the minimum value up to the present;
When it is determined that the minimum voltage or the maximum voltage up to the present in the minimum voltage / maximum voltage detection step, this voltage value is output as the minimum voltage or the maximum voltage, and up to the present in the minimum voltage / maximum voltage detection step. When it is not determined that the minimum voltage or the maximum voltage, the step of updating to the voltage value detected in the voltage detection step,
An alarm that determines whether the maximum value / minimum value of the voltage detected in the minimum voltage / maximum voltage detection step exceeds a second threshold value, and issues an alarm when the second threshold value is exceeded. An output process;
A voltage measuring method characterized by comprising:

Images