JP2010267613A - Transformer excitation rush current suppression control method and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress an excitation rush current generated when a 3-phase alternating current transformer is connected by turning on a breaker. <P>SOLUTION: A residual magnetic flux is measured at a time when the 3-phase alternating current transformer is shut down, and the controlled phase and the controlled phase angle are measured in which the excitation rush current becomes smallest from that residual magnetic flux. By carrying out a turn-on controlling of the 3-phase alternating current transformer by that controlled phase and the controlled phase angle, the excitation rush current that is generated when the 3-phase alternating current transformer is connected and used in an electric power system including high harmonic waves is suppressed and controlled. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a transformer excitation inrush current suppression control method and a transformer excitation inrush current suppression control apparatus for suppressing control of excitation inrush current generated when a transformer is connected to a power system including harmonics. Is.

  Conventionally, when a transformer is connected to an electric power system and used, the inrush current is suppressed by controlling the connection phase angle. For example, in Japanese Patent Application Laid-Open No. 11-345546 (Patent Document 1), the transformer is disconnected after a predetermined time from the time of the voltage zero point of the reference phase when the circuit breaker provided at the terminal of the transformer is shut off. In addition, it is described that a control reference point is obtained by using a zero cross converter in order to turn on the transformer after a predetermined time from the time of the voltage zero point of the reference phase during the closing operation of the circuit breaker.

  Further, in Japanese Patent Laid-Open No. 10-164754 (Patent Document 2), when it is detected that the power supply to the transformer is cut off, the phase angle of the power supply voltage at the time of power cut-off is stored, and When it is detected that the power is turned on again, the power-on timing for reducing the inrush current is obtained based on the stored power-supply voltage phase angle at the previous shut-off, and the switching element is turned on when that timing is reached. Is described.

  In Japanese Patent Laid-Open No. 55-100034 (Patent Document 3), the terminal voltage phase of the transformer at the time when the circuit breaker provided at the terminal of the transformer is opened is stored, and the circuit breaker is turned on again. It is described that the power supply voltage phase is controlled to match the stored voltage phase.

JP-A-11-345546 JP-A-10-164754 Japanese Patent Laid-Open No. 55-100034

  However, in the technique of the above-mentioned Patent Document 1, as shown by 101 in FIG. 23, there are cases where three times of the voltage zero point are detected in a waveform including harmonics, and the zero cross converter does not function effectively. .

  Further, in the technology of Patent Document 2, the phase angle of the power supply voltage of the low-voltage single-phase transformer is detected and a switching element is used as a switch. However, in a special high-voltage power system, the rated voltage is 500,000 V, There is a problem that there is no switching element that can handle a rated breaking current of about 50,000 A, and that it cannot be handled.

  Further, in the technique of Patent Document 3, since there is no detection means by actual measurement, as shown in FIG. 24, when a short circuit accident or the like occurs in the power system, it is as if the transformer is located before the breaker operating point 111 by the relay operation. Since the circuit breaks, the residual magnetic flux detection before the circuit breaker is opened is most effective. FIG. 24 shows the calculation results of the transformer voltage and magnetic flux when a 3-wire short-circuit accident occurs in the power system. The residual magnetic flux varies depending on the accident occurrence phase angle. For example, the accident occurrence phase angle is 138.3 degrees for the a phase, 19.5 degrees for the b phase, and 255.6 degrees for the c phase. On the other hand, the residual magnetic flux is 0.73 for the a phase, -0.42 for the b phase, and -0.31 for the c phase. The optimal control phase is the c phase and the control phase angle is -72 degrees. In the technique of Patent Document 3, since the c-phase is turned on at 255.6 degrees, the circuit breaker is turned on at a phase difference of 32 degrees, and a considerable excitation inrush current flows through the transformer.

  The present invention solves the above-mentioned problems, and the object of the present invention is to measure the residual magnetic flux when the three-phase AC transformer is interrupted, and to control the control phase and the control that minimize the magnetizing inrush current from the residual magnetic flux. By detecting the phase angle and controlling the input of the three-phase AC transformer with the control phase and the control phase angle, excitation generated when the three-phase AC transformer is connected to the power system including harmonics. It is an object of the present invention to provide a transformer excitation inrush current suppression control method and a transformer excitation inrush current suppression control device capable of suppressing the inrush current.

In order to achieve the above object, a first configuration of a transformer excitation inrush current suppression control method according to the present invention is the introduction of a circuit breaker provided at a terminal of a three-phase AC transformer provided in a power system including harmonics. A time difference between a preset phase angle of a specific phase, a time when a closing command is given to the circuit breaker by a closing command, and a time when the circuit breaker is actually turned on. When a closing addition time is obtained from the closing time which is the shortest time and a closing command for the circuit breaker is received, VB (a), VB (b), VB ( c): instantaneous value of bus voltage, Vm: maximum value of bus voltage, θ: phase angle of a specific phase, VB: instantaneous value of bus voltage of a specific phase,
To determine the input phase phase angle at the time of the first sampling by the sin ⁻¹ phase angle method at the time of receiving the input command, and to determine the input phase phase angle at the time of the second sampling by the sin ⁻¹ phase angle method. The input phase angle change width obtained by subtracting the input phase angle at the first sampling from the input phase angle at the time of sampling represents the time obtained by subtracting the first sampling time from the second sampling time. A value larger than the sampling time width and smaller than twice the sampling time width is set as the input reference point, and the sum with the input addition time is set as the input waiting time. It is characterized by giving to.

The second configuration of the transformer inrush current suppression control method according to the present invention, the transformer in the first configuration of the magnetizing inrush current suppression control method, the method of the transformer inrush current suppression the first configuration By the above, the closing time of the inserted circuit breaker is overwritten on the previous charging time as the latest charging time.

The third configuration of the transformer excitation inrush current suppression control method according to the present invention includes each of the circuit breakers introduced by the transformer excitation inrush current suppression method of the first configuration at the time when the circuit breaker is actually turned on. The phase angle of the phase bus voltage, the bus effective value voltage before the predetermined time and the predetermined time after the time when the circuit breaker introduced by the transformer excitation inrush current suppression method of the first configuration is actually turned on Displaying at least one of an instantaneous voltage drop amount that is a difference from a bus effective value voltage minimum value and a latest turn-on time in the transformer excitation inrush current suppression method of the second configuration, To do.

The fourth configuration of the transformer inrush current suppression control method according to the present invention, in the first configuration of the transformer inrush current suppression control method, time of the circuit breaker is actually turned on, the It is characterized by the time when the overvoltage detector detects the secondary voltage change of the circuit breaker of the three-phase AC transformer.

Further, a fifth configuration of the transformer excitation inrush current suppression control method according to the present invention is, in the fourth configuration of the transformer excitation inrush current suppression control method, one sampling before the turn-on time detected by the overvoltage detector. The fundamental voltage was extracted by Fourier expansion of the bus voltage data for one cycle from 1 and the value obtained by adding the phase angle for one sampling to the phase angle of the fundamental wave was used as the input phase angle of the three-phase AC transformer It is characterized by.

Moreover, the 1st structure of the transformer excitation inrush current suppression control apparatus which concerns on this invention is an apparatus which controls injection | throwing-in of the circuit breaker provided in the terminal of the three-phase alternating current transformer provided in the electric power system containing a harmonic. It is the shortest time among the time difference between a preset phase angle of a specific phase set in advance, a time when the closing command is given to the circuit breaker by a closing command, and a time when the circuit breaker is actually turned on Upon receipt of a closing addition time calculation means for determining a closing addition time from a closing time and a closing command for the circuit breaker, VB (a), VB (b), VB (c) are obtained from the instantaneous value of the bus voltage sampled at the time of reception. ): Instantaneous value of bus voltage, Vm: maximum value of bus voltage, θ: phase angle of a specific phase, VB: instantaneous value of bus voltage of a specific phase,
The first input phase angle calculating means for obtaining the input phase phase angle at the first sampling at the time of receiving the input command by the sin ⁻¹ phase angle method, and the input phase phase angle at the second sampling at the time of receiving the input command as sin. a second closing phase angle calculating means for calculating ^-1 phase angle method, first determined by the second of the first closing phase angle calculating means from the closing phase angle of the time of sampling was calculated by the second closing phase angle calculation means 1 The input phase angle change width obtained by subtracting the input phase angle at the time of the sampling is larger than the sampling time width expressed by the phase angle obtained by subtracting the first sampling time from the second sampling time, and the sampling time A charging reference point detecting means having a charging reference point smaller than twice the width, and a charging reference time is calculated from the charging reference point detected by the charging reference point detecting means. The input reference time calculating means, the input reference time calculated by the input reference time calculating means, and the sum of the input addition time obtained by the input addition time calculating means as an input waiting time, after the input waiting time has elapsed, And a closing command means for supplying a closing command to the circuit breaker.

The second configuration of the transformer magnetizing inrush current suppression control apparatus according to the present invention, in the first configuration of the transformer inrush current suppression control, the which is turned by the transformer inrush current suppression apparatus It is characterized by having a closing time changing means for overwriting the previous closing time with the closing time of the circuit breaker as the latest closing time.

Further, a third configuration of the transformer excitation inrush current suppression control device according to the present invention is the circuit breaker introduced by the transformer excitation inrush current suppression device of the first configuration of the transformer excitation inrush current suppression control device. The phase angle of each phase bus voltage at the time when is actually turned on, and the bus before a predetermined time before the time when the circuit breaker turned on by the transformer excitation inrush current suppression device of the first configuration is actually turned on The instantaneous voltage drop amount, which is the difference between the effective value voltage and the minimum value of the bus effective value voltage until a predetermined time, and the latest input time described in the second configuration of the transformer excitation inrush current suppression control device It has a display means for displaying at least one of them.

The fourth configuration of the transformer magnetizing inrush current suppression control apparatus according to the present invention, in the first configuration of the transformer inrush current suppression control, the time in which the circuit breaker is actually turned on, the It is characterized by the time when the overvoltage detector detects the secondary voltage change of the circuit breaker of the three-phase AC transformer.

The fifth configuration of the transformer magnetizing inrush current suppression control apparatus according to the present invention, in the fourth configuration of the transformer inrush current suppression control, before one sampling of input time the overvoltage detector detects The fundamental wave extracting means for extracting the fundamental wave by Fourier expansion of the bus voltage data for one cycle from the first cycle, and the value obtained by adding the phase angle for one sampling to the phase angle of the fundamental wave extracted by the fundamental wave extracting means And a making phase angle setting means for setting the making phase angle of the three-phase AC transformer.

The sixth configuration of the transformer excitation inrush current suppression control method according to the present invention is a method for controlling the breaking of a circuit breaker provided at a terminal of a three-phase AC transformer, and Φ m: maximum residual magnetic flux , Φr (a), Φr (b), Φr (c): residual magnetic flux of each phase, Φr (a) = Φm , Φr (b) = − Φm / 2, Φ It is characterized in that the cutoff phase angle of the transformer satisfies r (c) = − Φ m / 2.

Further, a seventh configuration of the transformer excitation inrush current suppression control method according to the present invention is a method for controlling the breaking of a circuit breaker provided at a terminal of a three-phase AC transformer, and is configured with a preset specific The cut-off addition phase angle is obtained from the cut-off time that is the shortest time among the time difference between the cut-off phase angle of the phase, the time when the cut-off command is given to the breaker by the cut-off command, and the time when the breaker is actually cut off When receiving the breaker command of the circuit breaker, VB (a), VB (b), VB (c): instantaneous value of the bus voltage, Vm: bus voltage, from the instantaneous value of the bus voltage sampled at the time of reception. , Θ: phase angle of a specific phase, VB: instantaneous value of the bus voltage of a specific phase,
The cutoff phase phase angle at the time of the first sampling is obtained by the sin ⁻¹ phase angle method when the cutoff command is received, and the cutoff phase phase angle at the time of the second sampling is obtained by the sin ⁻¹ phase angle method. The change width of the cut-off phase angle obtained by subtracting the cut-off phase angle at the time of the first sampling from the cut-off phase angle at the time of sampling represents the time obtained by subtracting the first sampling time from the second sampling time. A value larger than the sampling time width and smaller than twice the sampling time width is set as a cutoff reference point, and the sum with the cutoff addition time is set as a cutoff waiting time. It is characterized by giving to.

Further, an eighth configuration of the transformer excitation inrush current suppression control method according to the present invention is the seventh configuration of the transformer excitation inrush current suppression control method, wherein the transformer excitation inrush current suppression control method is interrupted by the transformer excitation inrush current suppression method. The breaking time of the circuit breaker is overwritten on the previous breaking time as the latest breaking time.

Further, a ninth configuration of the transformer excitation inrush current suppression control method according to the present invention is the seventh configuration of the transformer excitation inrush current suppression control method. It is characterized in that the time when the overvoltage detector detects a change in the difference voltage between the bus voltage of the three-phase AC transformer and the detected voltage of the transformer for detecting the bus voltage.

The first 0 of the configuration of a transformer inrush current suppression control method according to the present invention, in the ninth configuration of the transformer inrush current suppression control method, one sample of blocking time the overvoltage detector detects The fundamental voltage is extracted by performing Fourier expansion of the bus voltage data for one cycle from the front, and the value obtained by adding the phase angle for one sampling to the phase angle of the fundamental wave is defined as the cutoff phase angle of the three-phase AC transformer. It is characterized by that.

The first one configuration of a transformer inrush current suppression control method according to the present invention is blocked by the seventh to transformer magnetizing inrush current suppression method according to the configuration of the transformer inrush current suppression control method Further, at least one of the phase angle of each phase bus voltage at the time when the breaker is actually cut off and the latest break time described in the eighth configuration of the transformer excitation inrush current suppression control method Is displayed.

The sixth configuration of the transformer excitation inrush current suppression control device according to the present invention is a device that controls the breaking of the circuit breaker provided at the terminal of the three-phase AC transformer, and Φ m: maximum residual magnetic flux , Φ r (a), Φ r (b), Φ r (c): when the phase residual magnetic flux, Φ r (a) = Φ m, Φ r (b) = - Φ m / 2, Φ r (C) = − Φm / 2 It is characterized by having a cutoff phase angle calculating means for calculating a cutoff phase angle of the three-phase AC transformer that satisfies the following.

The seventh configuration of the transformer excitation inrush current suppression control device according to the present invention is a device that controls the breaking of the circuit breaker provided at the terminal of the three-phase AC transformer, The cut-off addition phase angle is obtained from the cut-off time which is the shortest time out of the time difference between the cut-off phase angle of the phase, the time when the cut-off command is given to the breaker by the cut-off command, and the time when the breaker is actually cut off When the interruption addition time calculation means and the interruption command of the breaker are received, VB (a), VB (b), VB (c): instantaneous value of the bus voltage, from the instantaneous value of the bus voltage sampled at the time of reception. Vm: maximum value of bus voltage, θ: phase angle of a specific phase, VB: instantaneous value of bus voltage of a specific phase,
The first cutoff phase angle calculating means for obtaining the cutoff phase angle at the time of the first sampling at the time of receiving the cutoff command by the sin ⁻¹ phase angle method, and the cutoff phase phase angle at the time of the second sampling at the time of receiving the cutoff command as sin. The first cutoff phase angle calculation means obtained from the second cutoff phase angle calculation means obtained by the ⁻¹ phase angle method and the cutoff phase angle at the time of second sampling obtained by the second cutoff phase angle calculation means. The cut-off phase angle change width obtained by subtracting the cut-off phase angle at the time of sampling is greater than the sampling time width in which the time obtained by subtracting the first sampling time from the second sampling time is represented by the phase angle, and the sampling time An interruption reference point detecting means having an interruption reference point having a value smaller than twice the width, and an interruption reference time is calculated from the interruption reference point detected by the interruption reference point detecting means. The interruption reference time calculating means, the interruption reference time calculated by the interruption reference time calculating means, and the sum of the interruption addition time obtained by the interruption addition time calculating means as the interruption waiting time, after the interruption waiting time has elapsed, And a shut-off command means for giving a shut-off command to the circuit breaker.

Further, an eighth configuration of the transformer excitation inrush current suppression control device according to the present invention is the seventh configuration of the transformer excitation inrush current suppression control device, wherein the transformer excitation inrush current suppression control device is cut off by the transformer excitation inrush current suppression device. It is characterized by having a break time changing means for overwriting the previous break time with the break time of the breaker as the latest break time.

Further, the ninth configuration of the transformer excitation inrush current suppression control device according to the present invention is the seventh configuration of the transformer excitation inrush current suppression control device, wherein the time when the breaker is actually interrupted is It is characterized in that the time when the overvoltage detector detects a change in the difference voltage between the bus voltage of the three-phase AC transformer and the detected voltage of the transformer for detecting the bus voltage.

The first 0 of the configuration of a transformer inrush current suppression control apparatus according to the present invention, in the eighth aspect of the transformer inrush current suppression control, one sample of blocking time the overvoltage detector detects The fundamental voltage is extracted by performing Fourier expansion of the bus voltage data for one cycle from the front, and the value obtained by adding the phase angle for one sampling to the phase angle of the fundamental wave is defined as the cutoff phase angle of the three-phase AC transformer. It is characterized by that.

The first one configuration of a transformer inrush current suppression control apparatus according to the present invention, in the seventh time transformer inrush said breaker is blocked by the current suppression device is actually blocked configuration of It has a display means for displaying at least one of the phase angle of each phase bus voltage and the latest breaking time described in the transformer excitation inrush current suppression device of the eighth configuration.

According to the first configuration of the transformer excitation inrush current suppression control method according to the present invention, the input reference point of the system including harmonics can be detected by the change width sin ⁻¹ phase angle detection method. It is possible to solve the problem that a plurality of points are detected by the detection by the zero cross converter as described in.

In addition, according to the second configuration of the transformer excitation inrush current suppression control method according to the present invention, each time the circuit breaker is turned on, the current turn-on time is overwritten on the previous turn-on time as the latest turn-on time. It can be updated at any time in the addition time.

Further, according to the third configuration of the transformer excitation inrush current suppression control method according to the present invention, the phase angle of each phase bus voltage, the instantaneous voltage drop amount, the latest application time at the time when the circuit breaker is actually turned on. By displaying, it is possible to easily monitor and control the transformer.

According to the fourth configuration of the transformer excitation inrush current suppression control method according to the present invention, the circuit breaker actually indicates the time when the overvoltage detector detects the secondary voltage change of the circuit breaker of the three-phase AC transformer. The time when the circuit breaker is turned on can be accurately detected.

Moreover, according to the 5th structure of the transformer excitation inrush current suppression control method which concerns on this invention, it can be set as the making-up phase angle of a three-phase alternating current transformer based on a fundamental wave.

In addition, according to the first configuration of the transformer excitation inrush current suppression control device according to the present invention, the input reference point of the system including harmonics can be detected by the change width sin ⁻¹ phase angle detection method. It is possible to solve the problem that a plurality of points are detected by the detection by the zero cross converter as described in Document 1.

Further, according to the second configuration of the transformer excitation inrush current suppression control device according to the present invention, every time when the circuit breaker is turned on, the closing time is overwritten as the latest closing time by the closing time changing means. Therefore, it can be updated at any time to the latest addition time.

Further, according to the third configuration of the transformer excitation inrush current suppression control device according to the present invention, the phase angle of each phase bus voltage, the instantaneous voltage drop amount, the latest voltage at the time when the circuit breaker is actually turned on by the display means. By displaying the input time of the transformer, it is possible to easily monitor and control the transformer.

Moreover, according to the 4th structure of the transformer excitation inrush current suppression control apparatus which concerns on this invention, it was set as the time when the overvoltage detector detected the secondary side voltage change of the circuit breaker of a three-phase alternating current transformer, It is possible to accurately detect the circuit breaker time.

According to the fifth configuration of the transformer excitation inrush current suppression control device according to the present invention, the input phase of the three-phase AC transformer is set by the input phase angle setting means based on the fundamental wave extracted by the fundamental wave extraction means. You can set the corner.

In addition, according to the sixth configuration of the transformer excitation inrush current suppression control method according to the present invention, Φr (a) = Φm , Φr (b) = − Φm / 2, Φr (c) = -By setting the cutoff phase angle of the transformer that satisfies Φm / 2, the cutoff phase angle that minimizes the magnetizing inrush current in a one-phase saturation state can be obtained.

Further, according to the seventh configuration of the transformer excitation inrush current suppression control method according to the present invention, it is possible to detect the cutoff reference point of the system including harmonics by the change width sin ⁻¹ phase angle detection method. It is possible to solve the problem that a plurality of points are detected by the detection by the zero cross converter as described in Document 1.

Further, according to the eighth configuration of the transformer excitation inrush current suppression control method according to the present invention, the latest breaking time is overwritten on the previous breaking time as the latest breaking time for each breaking of the breaker. The cutoff addition phase angle can be updated at any time.

In addition, according to the ninth configuration of the transformer excitation inrush current suppression control method according to the present invention, the voltage difference between the bus voltage of the three-phase AC transformer and the detection voltage of the transformer for detecting the bus voltage is overvoltage. By setting the time detected by the detector, it is possible to accurately detect the break time of the breaker.

Further, according to the first 0 of the configuration of a transformer inrush current suppression control method according to the present invention, it is possible to cut off the phase angle of the three-phase AC transformer based on the fundamental wave.

Further, according to the first 1 of the configuration of the transformer inrush current suppression control method according to the present invention, the phase angle of each phase bus voltage at the time the circuit breaker is actually cut off, to display the most recent interruption time Therefore, it is easy to monitor and control the transformer.

Further, according to the sixth configuration of the transformer excitation inrush current suppression control device according to the present invention, Φr (a) = Φm , Φr (b) = − Φm / 2, Φr (c) = -By calculating the cutoff phase angle of the transformer that satisfies Φm / 2 by the cutoff phase angle calculation means, the cutoff phase angle that minimizes the magnetizing inrush current in the one-phase saturation state can be obtained.

Further, according to the seventh configuration of the transformer excitation inrush current suppression control device according to the present invention, it is possible to detect the cutoff reference point of the system including harmonics by the change width sin ⁻¹ phase angle detection method. It is possible to solve the problem that a plurality of points are detected by the detection by the zero cross converter as described in Document 1.

Moreover, according to the 8th structure of the transformer excitation inrush current suppression control apparatus which concerns on this invention, the interruption | blocking time is overwritten on the last interruption | blocking time as the newest interruption | blocking time for every interruption | blocking of a circuit breaker by interruption | blocking time change means. Thus, it is possible to update to the latest cutoff addition phase angle as needed.

In addition, according to the ninth configuration of the transformer excitation inrush current suppression control device according to the present invention, the voltage difference between the bus voltage of the three-phase AC transformer and the detection voltage of the transformer for detecting the bus voltage is overvoltage. By setting the time detected by the detector, it is possible to accurately detect the break time of the breaker.

Further, according to the first 0 of the configuration of a transformer inrush current suppression control apparatus according to the present invention, based on the fundamental wave extracted by the fundamental wave extraction means, 3-phase AC transformer by interrupting the phase angle setting means The cutoff phase angle can be set.

In addition, according to the first configuration of the transformer excitation inrush current suppression control device according to the present invention, the phase angle of each phase bus voltage at the time when the circuit breaker is actually shut off by the display means, and the latest breaking time are obtained. By displaying, it is easy to monitor and control the transformer.

It is a circuit diagram which shows the structure of the transformer excitation inrush current suppression control apparatus which concerns on this invention. It is a block diagram explaining the internal structure of a calculating part. It is a block diagram explaining the internal structure of a calculating part. It is a figure which shows an example of a setting screen. It is a figure which shows an example of the monitoring screen. It is a figure which shows an example of an insertion / blocking setting screen. It is a flowchart explaining operation | movement of the transformer excitation inrush current suppression control apparatus which concerns on this invention. It is a figure which shows the correlation with the interruption | blocking phase angle of a transformer, and a residual magnetic flux. It is a figure which shows the correlation of the magnetic flux and electric current of a 1 phase saturation state. It is a figure which shows the correlation of the magnetic flux and electric current of a two-phase saturation state. It is a time chart explaining the interruption | blocking control of a transformer. It is a figure which shows an example of the measurement result of residual magnetic flux. It is a figure which shows a mode that the interruption | blocking verification is performed by the interruption | blocking time detector. It is a figure which shows a mode that the interruption | blocking time is verified by the interruption | blocking time measuring device. It is a figure which shows the correlation of a interruption | blocking phase angle and a residual magnetic flux. It is a flowchart which shows a mode that determination of a phase angle is performed. It is a time chart which shows the input control of a transformer. It is a figure which shows a mode that injection | throwing-in is verified by the insertion time detector. It is a figure which shows a mode that input time is verified by the input time measuring device. It is a figure which shows the change of the bus-line voltage and transformer current at the time of performing the injection control of a transformer with the transformer excitation inrush current suppression control apparatus which concerns on this invention. The phase angle of the bus voltage is calculated with a sin ⁻¹ phase angle detector, the phase angle is further calculated with the next sampling value, and the change width is detected to be less than twice the sampling phase angle. FIG. It is a figure which shows the change of the bus-line voltage and transformer current at the time of throwing in a transformer by conventional control. It is a figure explaining the subject of patent document 1. FIG. It is a figure explaining the subject of patent document 3. FIG.

An embodiment of a transformer excitation inrush current suppression control method and a transformer excitation inrush current suppression control device according to the present invention will be specifically described with reference to the drawings. 1 is a circuit diagram showing a configuration of a transformer excitation inrush current suppression control device according to the present invention, FIGS. 2 and 3 are block diagrams illustrating an internal configuration of a control unit, and FIG. 4 is a diagram showing an example of a setting screen, FIG. 5 is a view showing an example of a monitoring screen, FIG. 6 is a view showing an example of an on / off setting screen, FIG. 7 is a flowchart for explaining the operation of the transformer excitation inrush current suppression control device according to the present invention, and FIG. Fig. 9 is a diagram showing the correlation between the breaking phase angle of the transformer and the residual magnetic flux, Fig. 9 is a diagram showing the correlation between the magnetic flux and current in the one-phase saturation state, and Fig. 10 is the correlation between the magnetic flux and current in the two-phase saturation state. FIG. 11 is a time chart explaining the transformer breaking control, FIG. 12 is a diagram showing an example of the measurement result of the residual magnetic flux, and FIG. 13 is a diagram showing how the breaking time is verified by the breaking time detector. FIG. 14 is a diagram showing a state in which the shut-off time is verified by the shut-off time measuring device, and FIG. Fig. 16 is a flowchart showing how the phase angle is determined, Fig. 17 is a time chart showing how the transformer is turned on, and Fig. 18 is a time chart showing the turning-on control of the transformer. FIG. 19 is a diagram illustrating a state in which the input time is verified by the input time measuring device, and FIG. 20 is a diagram illustrating a control for turning on the transformer by the transformer excitation inrush current suppression control device according to the present invention. FIG. 21 is a diagram showing changes in the bus voltage and the transformer current when it is performed. FIG. 21 calculates the phase angle of the bus voltage with a sin ⁻¹ phase angle detector, and further calculates the phase angle with the next sampling value. Fig. 22 illustrates how the change width is larger than the sampling phase angle and less than twice the sampling phase angle. Fig. 22 shows changes in bus voltage and transformer current when the transformer is turned on under conventional control. FIG.

  In FIG. 1, reference numeral 1 denotes a main circuit of a three-phase AC transformer 2 connected to a bus 4, which is connected to the bus 4 and is provided with a bus voltage detection transformer (VT-1 provided on the primary side of the transformer 2. ) 5 and a transformer primary side circuit breaker (VT-1) 5 and a transformer primary side circuit breaker which is provided between the primary side terminal of the transformer 2 and is capable of interrupting the primary side of the transformer 2 CB-1) 6, transformer secondary circuit breaker (CB-2) 8 provided at the secondary terminal of transformer 2 and capable of interrupting the secondary side of transformer 2, and bus 4 And a transformer secondary circuit breaker (CB-2) 8 and a detection transformer (VT-2) 7 provided between the transformer 2.

  3 is a circuit breaker operation switch for controlling the circuit breaker on / off of the transformer primary circuit breaker (CB-1) 6, and 9 is a circuit breaker operation for the transformer primary circuit breaker (CB-1) 6. 10 is a closing operation switch for performing the closing operation of the transformer primary circuit breaker (CB-1) 6.

  11 is a transformer excitation inrush current suppression control device for controlling the on / off of the transformer primary circuit breaker 6 provided at the terminal of the three-phase AC transformer 2, and is transformed by the detection transformers 5 and 7. The input buses 13 and 14 which convert the bus voltage and the secondary side voltage of the three-phase AC transformer 2 into voltages suitable for the control unit 12 shown in FIGS. Auxiliary device 15 for notifying the breaker command of the breaker 6, an auxiliary device 16 for notifying the control unit 12 of a closing command for the breaker 6, and a switching circuit 17 for giving the breaker 6 breaking command from the control unit 12 to the breaker 6 at high speed , A switching circuit 18 that gives the circuit breaker 6 input command from the control unit 12 to the circuit breaker 6 at a high speed, a high-speed circuit command detector 19 that notifies the control unit 12 of a circuit break command to the circuit breaker 6 at high speed It has a high-speed input command detector 20 that notifies the control unit 12 at high speed Constructed.

  Reference numeral 21 denotes a circuit breaker operation circuit, which is constituted by a general-purpose operation circuit for the transformer primary circuit breaker 6. 22 is a trip coil for converting electrical signals into mechanical force, 23 is a closing coil for converting electrical signals into mechanical force, and 24 and 25 are auxiliary switches.

2 and 3 are diagrams showing the configuration of the control unit 12. The residual magnetic flux measuring device 26 for measuring the residual magnetic flux when the three-phase AC transformer 2 is cut off, and the three-phase measured by the residual magnetic flux measuring device 26. Among them, a closing phase setting device 27 serving as a closing phase setting means having a minimum phase of the absolute value of the residual magnetic flux as a closing phase, and using the value of the residual magnetic flux of the closing phase set by the closing phase setting device 27, Φ r (min): minimum value of the absolute value of the residual magnetic flux of the three-phase AC transformer 3 phases during interrupting of, theta: when the phase ^{angle, θ = cos -1 (- Φ} r (min) ), An optimum closing phase angle calculator 28 serving as a closing phase angle calculating means for calculating two θ, Φ r (a), Φ r (b), Φ r (c): residual magnetic flux of each phase, Ik ( a, 1), Ik (b, 1), Ik (c, 1): virtual inrush current of each phase at first θ, Ik (a, 2), Ik (b, 2), Ik (C, 2): Ik (a, 1) = cos (θ) + Φr (a), Ik (b, 1) = cos () when assuming a virtual inrush current of each phase at the second θ. θ−120) + Φr (b), Ik (c, 1) = cos (θ + 120) + Φr (c), Ik (a, 2) = cos (−θ) + Φr (a), Ik ( b, 2) = cos (−θ−120) + Φr (b), Ik (c, 2) = cos (−θ + 120) + Φr (c) A virtual inrush current calculator 29 serving as a virtual inrush current calculator for obtaining a virtual inrush current for each of the first and second solutions of the phase θ, and the absolute value of each virtual inrush current obtained by the virtual inrush current calculator 29 A transformer closing device 30 serving as a breaker closing control means for controlling the closing of the breaker 6 with θ being a value of 1 or less as a closing phase angle.

In addition, the control unit 12 sets a time difference between a preset phase angle of a specific phase, a time when a closing command is given to the circuit breaker 6 by a closing command, and a time when the circuit breaker 6 is actually turned on. When the addition addition time calculator 31 serving as the addition addition time calculation means for obtaining the addition addition time from the closing time that is the shortest time and the closing instruction of the circuit breaker 6 are received, from the instantaneous value of the bus voltage sampled at the time of reception, VB (a), VB (b), VB (c): instantaneous value of bus voltage, Vm: maximum value of bus voltage, θ: phase angle of a specific phase, VB: instantaneous value of bus voltage of a specific phase When
Thus, a first closing phase angle calculator 78 serving as a first closing phase angle calculating means for obtaining a closing phase angle at the time of the first sampling at the time of receiving the closing command by a sin ⁻¹ phase angle method, and a second at the time of receiving the closing command. The second input phase angle calculator 79 serving as the second input phase angle calculation means for calculating the input phase angle at the time of sampling by the sin ⁻¹ phase angle method, and the second input phase angle calculator 79 obtained by the second input phase angle calculator 79. The input phase angle variation obtained by subtracting the input phase angle at the time of the first sampling obtained by the first input phase angle calculator 78 from the input phase angle at the time of sampling is the first sampling time from the second sampling time. An input reference inspection that is an input reference point detection means having an input reference point that is larger than the sampling time width represented by the phase angle, minus the sampling time, and smaller than twice the sampling time width. An output reference time calculator 34 serving as a reference input time calculation means for calculating an input reference time from an input reference point detected by the input reference point detector 71, and an input reference time calculator 34. The sum of the input reference time and the input addition time obtained by the input addition time calculator 31 is set as an input waiting time, and an input command as an input command means for supplying an input command to the circuit breaker 6 after the input waiting time has elapsed. And an output device 36.

  In addition, it has a closing time setting device 37 serving as a closing time changing means for overwriting the previous closing time with the closing time of the circuit breaker 6 inserted by the transformer excitation inrush current suppressing device 11 as the latest closing time.

  Further, the phase angle of each phase bus voltage at the time when the circuit breaker 6 turned on by the transformer excitation inrush current suppressing device 11 is actually turned on, and the circuit breaker 6 turned on by the transformer excitation inrush current suppressing device 11. The amount of instantaneous voltage drop that is the difference between the bus RMS value before the predetermined time and the minimum bus RMS voltage before the predetermined time, and the latest overwritten by the closing time setter 37 as needed. The display unit 38 is provided as a display means for displaying the charging time of.

  The time when the circuit breaker 6 is actually turned on is the time when the overvoltage detector 47 detects the change in the secondary voltage of the circuit breaker 6 of the three-phase AC transformer 2.

  Further, the control unit 12 includes a fundamental wave extractor 94 serving as a fundamental wave extraction unit for extracting a fundamental wave by performing Fourier expansion on the bus voltage data for one cycle from one sampling before the input time detected by the overvoltage detector 47. The closing phase angle is a closing phase angle setting means for setting a value obtained by adding the phase angle of one sampling to the phase angle of the fundamental wave extracted by the fundamental wave extractor 94 as the closing phase angle of the three-phase AC transformer 2. An angle setting unit 77 is included.

In addition, the control unit 12 determines that Φ m (maximum residual magnetic flux), Φ r (a), Φ r (b), Φ r (c): residual magnetic flux of each phase, Φ r (a) = Φ m, Φ A cutoff phase angle setting unit 39 is provided as a cutoff phase angle calculating means for calculating the cutoff phase angle of the transformer 2 satisfying r (b) = − Φ m / 2 and Φ r (c) = − Φ m / 2. is doing.

Further, the control unit 12 includes a time difference between a preset phase cutoff phase angle, a time when the cutoff command is given to the circuit breaker 6 by the cutoff command, and a time when the circuit breaker 6 is actually shut down. When the interruption addition time calculator 40 serving as the interruption addition time calculating means for obtaining the interruption addition phase angle from the interruption time which is the shortest time, and the interruption command of the interruption circuit 6 are received, VB is obtained from the instantaneous value of the bus voltage sampled at the reception. (A), VB (b), VB (c): instantaneous value of bus voltage, Vm: maximum value of bus voltage, θ: phase angle of specific phase, VB: instantaneous value of bus voltage of specific phase Sometimes,
Accordingly, a first cutoff phase angle calculator 81 serving as a first cutoff phase angle calculating means for obtaining a cutoff phase angle at the time of first sampling at the time of reception of the cutoff command by a sin ⁻¹ phase angle method, and a second at the time of reception of the cutoff command. The second cutoff phase angle calculator 82 serving as a second cutoff phase angle calculation means for obtaining the cutoff phase phase angle at the time of sampling by the sin ⁻¹ phase angle method, and the second cutoff phase angle calculator 82 obtained by the second cutoff phase angle calculator 82. The cut-off phase angle change width obtained by subtracting the cut-off phase angle at the first sampling obtained by the first cut-off phase angle calculator 81 from the cut-off phase angle at the time of sampling is the first sampling from the second sampling time. An interruption reference point detector 62 serving as an interruption reference point detecting means having an interruption reference point having a value larger than the sampling time width represented by the phase angle and the time obtained by subtracting the time being smaller than twice the sampling time width. A cutoff reference time calculator 41 serving as a cutoff reference time calculation means for calculating a cutoff reference time from the cutoff reference point detected by the cutoff reference point detector 62, and a cutoff reference time calculated by the cutoff reference time calculator 41. Then, the sum of the interruption addition time obtained by the interruption addition time calculator 40 serving as the interruption addition time calculating means is defined as the interruption waiting time, and the interruption serving as the interruption instruction means for giving the interruption instruction to the breaker 6 after the interruption waiting time has elapsed. A command output device 43 is provided.

  In addition, the control unit 12 sets a cut-off time setting device 44 serving as a cut-off time changing unit that overwrites the previous cut-off time with the cut-off time of the breaker 6 cut off by the transformer excitation inrush current suppressing device 11 as the latest cut-off time Have.

  Further, the control unit 12 changes the difference voltage between the bus voltage of the three-phase AC transformer 2 and the detected voltage of the transformer for detecting the bus voltage, when the transformer primary circuit breaker 6 is actually cut off. Is the time when the overvoltage detector 47 detects.

  Further, the control unit 12 has a fundamental wave extractor 94 as fundamental wave extraction means for extracting a fundamental wave by performing Fourier expansion of the bus voltage data for one cycle from one sampling before the cutoff time detected by the overvoltage detector 47; The cutoff phase is a cutoff phase angle setting means for setting the value obtained by adding the phase angle of one sampling to the phase angle of the fundamental wave extracted by the fundamental wave extractor 94 as the cutoff phase angle of the three-phase AC transformer 2 And an angle setting device 39.

  Further, the control unit 12 updates the phase angle of each phase bus voltage at the time when the circuit breaker 6 interrupted by the transformer excitation inrush current suppression device 11 is actually interrupted, and the latest overwritten by the interruption time setting unit 44 as needed. The display unit 38 is configured as a display means for displaying the blocking time.

  As shown in FIG. 22, when the three-phase AC transformer 2 is connected to the power system without performing special input control (transformer input), an excessive current excitation current flows, causing malfunction of the transformer protection device, It is known that an instantaneous voltage drop occurs. FIG. 22 is a graph showing the relationship between the magnetizing inrush current and the bus voltage when the input control of the three-phase AC transformer 2 is not performed, and FIG. 20 is a graph showing the transformer magnetizing inrush current suppressing device 11 according to the present invention. It is a graph which shows the relationship between the magnetizing inrush current at the time of performing charging control of the three-phase alternating current transformer 2, and bus voltage. In FIGS. 20 and 22, a unit of voltage with a predetermined reference voltage as 1 pu and a unit of current with 10 MVA base current as 1 pu are shown.

  FIG. 4 is a setting input screen 46 on which various setting information input by the input device 45 shown in FIG. 2 is displayed by the display unit 38. Three-phase alternating current is clicked by clicking a list button 46a1 provided in the frequency selection field 46a. The frequency of the system provided with the transformer 2 is appropriately selected and input from “50 Hz” or “60 Hz”.

  Further, the transformer tap voltage column 46b is appropriately input with a numerical value of the transformer tap voltage (kV) when the transformer excitation inrush current suppression device 11 is used. The residual magnetic flux is corrected with the voltage set in the transformer tap voltage column 46b.

  Also, in the transformer connection column 46c, the primary connection, the secondary connection, and the tertiary connection are displayed as appropriate from "Y (star connection)", "△ (delta connection)", and "Chigori (chidori connection)". Select and input the connection to be applied. If there is no tertiary connection, “None” is selected.

  In addition, any one of “transformer primary side”, “transformer secondary side”, and “transformer tertiary side” is appropriately selected and input from the list in the transformer voltage capture location field 46d.

  FIG. 5 shows a monitoring control screen 48 for displaying the control command value set value of the circuit breaker 6 and the actual measured value of the on / off operation on the display unit 38. The input items related to the next on / off operation, the previous actual measured value. Is displayed with colored characters. FIGS. 6A and 6B are an input setting screen 49 and a cut-off setting screen 50 respectively displayed by the display unit 38 when the setting button 48a is clicked on the monitoring control screen 48 of FIG.

  When the next control time is a closing operation, the closing setting screen 49 shown in FIG. 6A is displayed. When the next control time is a blocking operation, the cutoff setting screen 50 shown in FIG. 6B is displayed. Is displayed. In addition, when the setting is not performed, the optimum control is performed. However, when the control phase and the control phase angle are changed, for example, when it is desired to generate a large magnetizing inrush current, each of the control phase fields 49a and 50a set in advance. When the phase wiring color is selected and input as appropriate, the phase angle value is appropriately input in each phase angle column 49b, 50b, and each decision button 49c, 50c is clicked, the shutdown input command value column on the monitoring control screen 48 in FIG. 48b is reflected and displayed. In the monitoring control screen 48 of FIG. 5, the previous closing input command value and the actual closing input value are displayed in the closing input command value column 48b and the actual closing input value 48c, respectively.

  When starting operation of the transformer excitation inrush current suppression device 11, the setting button 48a on the monitoring control screen 48 shown in FIG. 5 is clicked to display the making setting screen 49 and the breaking setting screen 50 shown in FIG. When the decision values 49c and 50c are clicked after inputting the command value and the cutoff command value, the operation of the transformer excitation inrush current suppression device 11 is set to start.

  Further, when performing the shut-off operation of the three-phase AC transformer 2, if the "turn-off" operation is performed by the shut-off operation switch 9 of FIG. 1, the operation is displayed in the shut-off input command value field 48b of the monitoring control screen 48 of FIG. A shutoff command is output at each shutoff command value. After the shut-off operation of the three-phase AC transformer 2, the actual shut-off input actual value is displayed in the actual shut-off input value field 48c of the monitoring control screen 48 of FIG. 5 by the operation of the transformer shut-off learning device 51 shown in FIG. Is done.

  In the shutdown input command value column 48b of the monitoring control screen 48 in FIG. 5, the measured time (ms) of each phase of the three-phase AC transformer 2 is shown in the operation time column 48c2 of the cutoff column 48c1. The cut-off / turn-in phase angle column 48c3 in the cut-off column 48c1 shows the measured values of the phase angle (degrees) of each phase when the three-phase AC transformer 2 is cut off. This makes it easy to check the control function.

  Further, the residual magnetic flux column 48d1 and the optimal control column 48d2 of the confirmation display column 48d of the monitoring control screen 48 in FIG. 5 include the residual magnetic flux necessary for the control of turning on the three-phase AC transformer 2, the control phase and the phase angle of the optimal control. Is displayed. The residual magnetic field 48d1 of the cutoff field 48d3 is the residual magnetic flux of each phase measured when the three-phase AC transformer 2 is shut off. The optimal control field 48d2 of the cutoff field 48d3 is The result of calculating the optimum control phase and the optimum phase angle with the displayed residual magnetic flux is displayed.

  On the other hand, in the closing operation of the three-phase AC transformer 2, if the “ON” operation is performed by the closing operation switch 10 shown in FIG. 1, the closing field 48 b 2 in the shut-off closing command value field 48 b of the monitoring control screen 48 in FIG. The input command is output with the displayed input command value.

  After the input operation of the three-phase AC transformer 2, the actual input values are displayed in the input field 48c4 of the cutoff input actual value field 48c of the monitoring control screen 48 of FIG. In the actual cut-off input value field 48c of the monitoring control screen 48 of FIG. 5, the measured value of the input time of each phase when the three-phase AC transformer 2 is turned on is displayed in the operation time field 48c2 of the input field 48c4. The measured value of the phase angle of each phase when the three-phase AC transformer 2 is turned on is displayed in the cutoff / turn-on phase angle column 48c3 of the closing column 48c4. This makes it easy to check the control function.

  Further, the instantaneous voltage drop amount (%) is displayed in the instantaneous voltage drop amount column 48d5 of the input column 48d4 of the confirmation display column 48d of the monitoring control screen 48 shown in FIG. The instantaneous voltage drop amount (%) at the previous turn-on is displayed in the upper row of the instantaneous voltage drop amount column 48d5 in the turn-on column 48d4, and the instantaneous voltage drop amount (%) at the current turn-on is displayed in the lower row. The

Figure 7 is a flow chart for explaining the operation of a transformer magnetizing inrush current suppression control apparatus 11 according to the present invention, will be described the outline, first, in step S _1, operated by a transformer settling input device 45 shown in FIG. 2 Perform initial settings before starting. In step S _2, it performs the blocking operation of the transformer primary circuit breaker 6 by interrupting the operation switch 9. Next, in step S ₃ , the control unit 12 receives the cutoff operation by the cutoff operation switch 9 in real time via the auxiliary device 15, and notifies the transformer primary side circuit breaker 6 of the cutoff command from the control unit 12. Then, the three-phase AC transformer 2 is shut off.

In step S _4, after interruption 3-phase AC transformer 2, the optimum charged operator 54 toward the next closing operation in non-real time for calculating the optimum charged information. Further, in step S _5, to learn the cut-off state of the 3-phase AC transformer 2 in a non-real time by the transformer cutoff learning apparatus 51.

Next, in step S ₆ , the closing operation of the transformer primary circuit breaker 6 is performed by the closing operation switch 10. In step S _7, the closing of the closing operation by the operation switch 10 receives the control section 12 via the auxiliary device 16 in real time, notifies the transformer primary circuit breaker 6 to closing command from the control unit 12 Then, the three-phase AC transformer 2 is turned on.

In step S _8, to learn the on state of the transformer turned learning apparatus 52 by 3-phase AC transformer 2 in a non-real time.

In step S ₁ in FIG. 7, the transformer settling input device 45 is turned on the setting screen 49 and a blocking setting screen 50 shown in FIG. 6, the input phase to be introduced, on time (ms), the input phase angle (degree), to cut off Set the cutoff phase, cutoff time (ms), and cutoff phase angle (degrees).

  FIG. 6A shows an example in which the input phase to be input is set to “blue”, and in FIG. 6B, the interrupting phase to be blocked is set to “white”. The charging time and breaking time are set with reference to the inspection data of the transformer primary breaker 6. The closing phase angle is automatically calculated after the three-phase AC transformer 2 is shut off.

As the cutoff phase angle of the three-phase AC transformer 2, in order to prevent a two-phase saturation phenomenon when the three-phase AC transformer 2 is shut down, a cutoff phase angle setting unit 39 serving as a cutoff phase angle calculation means is shown in FIG. as shown in the correlation diagram between the residual magnetic flux and the shutoff phase angle indicated, [Phi m: maximum residual magnetic flux, Φ r (a), Φ r (b), Φ r (c): when the phase residual magnetic flux, [Phi The cutoff phase angle satisfying r (a) = Φm , Φr (b) = − Φm / 2, Φr (c) = − Φm / 2 is calculated, and this is calculated as the three-phase AC transformer 2 The cutoff phase angle can be set.

  In FIG. 8, the horizontal axis indicates the a-phase reference cutoff phase angle (degrees), the vertical axis indicates the residual magnetic flux (pu), and 55 indicates a transformer in which a one-phase saturation phenomenon occurs when the three-phase AC transformer 2 is turned on. A cutoff zone 56 is a transformer cutoff zone in which a two-phase saturation phenomenon occurs when the three-phase AC transformer 2 is turned on.

  9 is an example of a correlation diagram of magnetic flux and current obtained by actually measuring the one-phase saturation phenomenon that occurs when the three-phase AC transformer 2 is turned on, and FIG. 10 is the two-phase saturation that occurs when the three-phase AC transformer 2 is turned on. It is an example of the correlation diagram of the magnetic flux and current which measured the phenomenon. 9 and 10, the horizontal axis represents time (ms), the vertical axis in FIG. 9 represents magnetic flux (pu) and current (A), and the vertical axis in FIG. 10 represents magnetic flux (pu) and current ( A) is shown. The magnetic flux (pu) is a unit of magnetic flux with a predetermined reference magnetic flux.

The interruption operation of the three-phase AC transformer ₂ shown in step S2 of FIG. 7 is performed by the interruption operation switch 9 shown in FIG. FIG. 11 is a time chart for explaining the interruption control of the three-phase AC transformer 2, and 57 indicates the operation time of the auxiliary device 15 shown in FIG. 58 is the phase angle detection time when the signal of the auxiliary device 15 is received and the phase angle of the bus voltage is calculated by the change width phase angle detector 60, and 59 is a cutoff command in consideration of the cutoff time and the control phase angle This is the shut-off command output time. Then, a trip command is given to the transformer primary circuit breaker 6 by the main circuit 1 and the high-speed switching circuit 17 shown in FIG. 1, and the three-phase AC transformer 2 is cut off.

Here, the change width phase angle detector 60 detects the phase angle of the bus voltage by the sin ⁻¹ phase angle detector 61 when the control unit 12 receives the interruption operation by the interruption operation switch 9 via the auxiliary device 15. The angle is calculated, the phase angle is further calculated with the next sampling value, and the change width is detected to be not more than twice the sampling phase angle.

That is, the interruption addition time calculator 40 serving as the interruption addition time calculation means shown in FIG. 2 gives an interruption command to the transformer primary circuit breaker 6 by the interruption phase angle of a specific phase set in advance and the interruption command. A reception addition phase angle calculating means is obtained by obtaining a cut-off addition phase angle from a cut-off time which is the shortest time among the time difference between the time when the transformer primary circuit breaker 6 is actually cut off. When the time phase angle calculator 32 receives a shut-off command for the transformer primary circuit breaker 6, VB (a), VB (b), VB (c): When instantaneous value of bus voltage, Vm: maximum value of bus voltage, θ: phase angle of specific phase, VB: instantaneous value of bus voltage of specific phase,
Thus, the first cutoff phase angle calculator 81 serving as the first cutoff phase angle calculation means obtains the cutoff phase angle at the time of the first sampling at the time of reception of the cutoff command by the sin ⁻¹ phase angle method, and calculates the second cutoff phase angle. the cut-off phase phase angle at the second sampling during disconnection instruction received by the second shutoff phase angle calculator 82 as a means determined by sin ^-1 phase angle method, by blocking the reference point detector 62 as a cutoff reference point detection means The cut-off phase angle variation obtained by subtracting the cut-off phase angle at the first sampling obtained by the first cut-off phase angle calculator 81 from the cut-off phase angle at the second sampling obtained by the second cut-off phase angle calculator 82 However, the value obtained by subtracting the first sampling time from the second sampling time is larger than the sampling time width represented by the phase angle and smaller than twice the sampling time width. To a point. Then, a cutoff reference time is calculated from the cutoff reference point detected by the cutoff reference point detector 62 by the cutoff reference time calculator 41 serving as a cutoff reference time calculation means. Then, the cutoff reference time calculated by the cutoff reference time calculator 41 by the cutoff command output device 43 serving as the cutoff command means and the cutoff addition time determined by the cutoff addition time calculator 40 serving as the cutoff addition time calculation means. Using the sum as the interruption waiting time, an interruption command is given to the transformer primary circuit breaker 6 after the interruption waiting time has elapsed.

FIG. 11 is a time chart for explaining an example of cutoff control of the three-phase AC transformer 2. 11, the work θ be performed in non-real-time, a cutoff phase angle of the blocking phase obtained in claim 1 2, breaking time is overwritten by a transformer interruption time overwriting 28 as a cutoff time changing means It is the latest breaking time of the transformer primary circuit breaker 6.

  As an example, if the cutoff phase angle (θ) is 60 degrees, and the cutoff time is 66.7 ms, the cutoff phase angle is 20 samplings and the cutoff time is 400 counts if the sampling count is corrected. Accordingly, the cutoff addition time is 100 counts.

As a work to be executed in real time, the phase angle calculation result at the time of the first sampling obtained by the first cutoff phase angle calculator 81 that receives the cutoff command and is the first cutoff phase angle calculation means is θ _1, and The phase angle calculation result at the time of the second sampling obtained by the second cutoff phase angle calculator 82 serving as the second cutoff phase angle calculator is θ _2, and the phase angle change of the value is larger than the sampling time width. The cutoff reference time is obtained with a value smaller than twice the sampling width as the cutoff reference point.

  As an example, when the cutoff reference point obtained by the cutoff reference point detector 62 is 30 degrees, the number of sampling counts is 10 counts, so the cutoff reference time calculator 41 calculates 110 counts.

  Therefore, since the interruption waiting time calculator 42 is the sum of the interruption addition time and the interruption reference time, the interruption waiting time is calculated as 210 counts.

  From these, after 210 counts from the start of the operation of the shut-off reference point detector 62, the shut-off command 59 is delivered to the shut-off command output device 43, and when the shut-off time of the transformer primary circuit breaker 6 has elapsed, the transformer The primary side circuit breaker 6 is interrupted.

  FIG. 12 shows the residual magnetic flux measurement result obtained by measuring the residual magnetic flux when the three-phase AC transformer 2 is cut off by the residual magnetic flux measuring device 26 shown in FIG. 12A shows a phase voltage waveform of the detection transformer 5, and FIG. 12B shows a magnetic flux waveform obtained by time-integrating the phase voltage of the detection transformer 5 shown in FIG. 12A. The convergent portion at the end becomes the residual magnetic flux. In FIG. 12, the horizontal axis represents time, the vertical axis in FIG. 12A represents voltage (pu), and the vertical axis in FIG. 12B represents magnetic flux (pu).

  The input phase setting unit 27 serving as the input phase setting means shown in FIG. 3 detects the phase having the smallest absolute value of the residual magnetic flux as the optimum input phase among the three phases of the three-phase AC transformer 2. For example, as shown in FIG. 12B, the residual magnetic flux is about -0.128 for "a phase", about +0.478 for "b phase", and about -0.341 for "c phase". "A phase" is detected as the optimum input phase.

The making phase angle setting unit 77 serving as the making phase angle calculating means shown in FIG. 3 uses the value of the residual magnetic flux of the optimum making phase detected by the making phase setting device 27, and Φ r (min): 3-phase AC transformer minimum value of the absolute value of the residual magnetic flux of the three phases during interruption of, theta: when the phase angle, θ = cos -1 - by ^(Φ r ^(min)), calculates a two theta, virtual A virtual inrush current calculator 29 serving as an inrush current calculating means Φr (a), Φr (b), Φr (c): residual magnetic flux of each phase, Ik (a, 1), Ik (b, 1), Ik (c, 1): virtual inrush current of each phase at the first θ, Ik (a, 2), Ik (b, 2), Ik (c, 2): each at the second θ When the virtual inrush current of the phase is assumed, Ik (a, 1) = cos (θ) + Φr (a), Ik (b, 1) = cos (θ−120) + Φr (b), Ik (c , 1) = cos (θ + 120) Φ r (c), Ik ( a, 2) = cos (-θ) + Φ r (a), Ik (b, 2) = cos (-θ-120) + Φ r (b), Ik (c, 2) = cos (−θ + 120) + Φ r (c), the virtual inrush current is obtained for each of the first and second solutions of θ of each phase, and the transformer charging device 30 serving as a circuit breaker charging control means The insertion of the transformer primary-side circuit breaker 6 is controlled by setting θ at which the absolute value of the virtual inrush current is 1 or less as the closing phase angle.

For example, as shown in FIG. 12B, the “a phase” residual magnetic flux Φ r (a) is about −0.128, the “b phase” residual magnetic flux Φ r (b) is about +0.478, When the residual magnetic flux Φ r (c) of “phase c” is about −0.341, “a phase” is detected as the minimum phase of the absolute value of the residual magnetic flux among the three phases of the three-phase AC transformer 2. , Θ = ± cos ⁻¹ (0.128) = ± 82.6 (degrees) is obtained by using the minimum absolute residual magnetic flux Φ r (min) = 0.128, and the first θ is +82 .6 (degrees) and the second θ is set to -82.6 (degrees).

  The virtual inrush current of each phase at the first θ (+82.6 (degrees)) is Ik (a, 1) = cos (82.6) −0.128, Ik (b, 1) = cos (82.6-120) + 0.478 = 1.272, Ik (c, 1) = cos (82.6 + 120) −0.341 = −1.264, and the second θ (−82.6 ( Degree)), the virtual inrush current of each phase is Ik (a, 2) = cos (−82.6) −0.128 = 0, Ik (b, 2) = cos (−82.6-120) ) + 0.478 = −0.445, Ik (c, 2) = cos (−82.6 + 120) −0.341 = 0.453, and θ of which the absolute value of the virtual inrush current is 1 or less is At the time of the second θ (−82.6 (degrees)), the transformer primary side cutoff is performed using the second θ (−82.6 (degrees)) as the input phase angle. The charging of the device 6 is controlled. Thereby, inrush current can be minimized for the three phases of the three-phase AC transformer 2.

  Next, as the cut-off reference point detector 62 shown in FIG. 2, the difference voltage (ΔV) between the bus voltage (VB) detected by the detection transformer 5 and the transformer voltage (VT) detected by the detection transformer 7. Is provided with an overvoltage detector 47, and its operation is set as a detection point. That is, the time when the transformer primary circuit breaker 6 is actually cut off is the bus voltage (VB) of the three-phase AC transformer 2 and the detection voltage of the transformer 7 for detecting the bus voltage (VB). The time when the overvoltage detector 47 detects the difference voltage change is set.

  FIG. 13 is a graph showing a state of detecting the cutoff time, where the horizontal axis represents the phase angle (degrees) and the vertical axis represents the voltage (pu). 63 and 64 are detection setting voltages of the overvoltage detector 47, and are set to ± 0.05 (pu) here. 65 is the “a-phase” bus voltage (VB) detected by the detection transformer 5, and 66 is the bus voltage (VB) of the three-phase AC transformer 2 and the transformer for detecting the bus voltage (VB). 7 shows a difference voltage change from the detection voltage of the device 7. Then, the time when the differential voltage 66 first reaches the detection setting voltages 63 and 64 of the overvoltage detector 47 is detected as the cutoff time 67.

  The detection of the cut-off time is detected by a transformer cut-off time detector 25 shown in FIG. Regarding the breaking time when the three-phase AC transformer 2 is cut off, the trip time measured in the repair record is a no-voltage opening time, so that zero-point breaking may be considered depending on the type of the transformer primary-side breaker 6 As a countermeasure against this, the interruption time setting unit 44 based on the learning function of the transformer interruption learning device 51 is obtained by calculating the time difference between the high-speed interruption command detector 19 and the interruption reference point detector 62 shown in FIG. The interruption time considering the zero point interruption can be measured. FIG. 14 is a diagram showing an example of the cutoff time detected by the transformer cutoff time detector 25. In FIG. In FIG. 14, the horizontal axis represents the sampling count number and the vertical axis represents the voltage (pu).

  The interruption time of the transformer primary circuit breaker 6 is overwritten as the latest interruption time every time by the transformer interruption time overwrite unit 28 serving as the interruption time changing means, and the monitoring control screen 48 shown in FIG. The operation time (interruption time) is displayed in the operation time field of the interruption field 48b1 of the interruption input command value field 48b.

  The cutoff phase angle setting unit 39 serving as the cutoff phase angle calculation means shown in FIG. 2 performs Fourier expansion of the bus voltage data for one cycle before one sampling from the cutoff time 67 shown in FIG. 13 detected by the cutoff reference point detector 62. To extract the fundamental wave, add one sampling to the phase angle, and measure the cutoff phase angle.

  Here, the correlation between the cutoff phase angle and the residual magnetic flux is shown in FIG. In FIG. 15, the horizontal axis represents the phase angle (degrees) and the vertical axis represents the residual magnetic flux (pu). In general, a large amount of data is required to obtain the XY correlation, but in this embodiment, the correlation can be returned to a sin function with one interruption phase angle and residual magnetic flux. Conventionally, to obtain this regression equation, at least three sets of data are required as shown in FIG.

Therefore, the actually measured residual magnetic flux and cutoff phase angle of each phase are obtained, and the phase angle of the residual magnetic flux of each phase is obtained. That is, the cutoff phase angle of the three-phase AC transformer 2 is

Since the cutoff phase angles θ (a), θ (b), θ (c) for each phase of the three-phase AC transformer 2 obtained by the above equation 8 are expressed by ± 90 degrees, the phase angles shown in FIG. With the determination processing flow, the cutoff phase angles θ (a), θ (b), and θ (c) for each phase of the three-phase AC transformer 2 can be expressed in the range of 0 to 360 degrees. First, in step S ₁₁ in FIG. 16, the process proceeds to step S ₁₂ when the residual magnetic flux "a phase" [Phi r (a) is 0 or more, the residual magnetic flux of the "c-phase" [Phi r (c) is " If the residual magnetic flux Φr (b) of “phase b” is greater than or equal to the cutoff phase angle θ (a), θ (b), θ (c) for each phase of the three-phase AC transformer 2 obtained by the above equation (12). ) (Step S ₁₅ ).

In step S _12, when the residual magnetic flux of the "c-phase" [Phi r (c) is less than the residual magnetic flux [Phi r (b) of "b phase", 3-phase obtained by the above equation (8) from 180 degrees The angle obtained by subtracting the cutoff phase angles θ (a), θ (b), and θ (c) for each phase of the AC transformer 2 is set as the cutoff phase angle (step S ₁₄ ).

In step S _11, the process proceeds to step S ₁₃ when the residual magnetic flux "a phase" [Phi r (a) is less than 0, the residual magnetic flux [Phi r of "b-phase" (b) is "c phase" if the residual magnetic flux Φ r (c) above, shutoff phase angle of each phase of the 3-phase AC transformer 2 obtained above equation (8) from 180 degrees θ (a), θ (b ), θ (c) The angle obtained by subtracting each of them is set as the cutoff phase angle (step S ₁₆ ).

In step S _13, when the residual magnetic flux of the "b-phase" [Phi r (b) is less than the residual magnetic flux [Phi r (c) of "c phase", 3-phase obtained by the above equation (8) to 360 degrees An angle obtained by adding the cutoff phase angles θ (a), θ (b), and θ (c) for each phase of the AC transformer 2 is defined as a cutoff phase angle (step S ₁₇ ).

  On the other hand, the closing operation of the three-phase AC transformer 2 is performed by the closing operation switch 10 shown in FIG. FIG. 17 is a charging control time chart of the three-phase AC transformer 2. In FIG. 17, 68 indicates the operation time of the auxiliary device 16 shown in FIG. 1, 69 indicates the operation signal of the auxiliary device 16, and the phase angle of the bus voltage is calculated by the change width phase angle detector 60 shown in FIG. This is the phase angle detection time to be applied, and an input command is given at the input command output time 70 in consideration of the input time and input phase angle of the three-phase AC transformer 2, and the three-phase AC transformer 2 is input.

Here, the change width phase angle detector 60 detects the phase angle of the bus voltage by the sin ⁻¹ phase angle detector 61 when the control unit 12 receives the input operation by the input operation switch 10 via the auxiliary device 16. The angle is calculated, the phase angle is further calculated with the next sampling value, and the change width is detected to be not more than twice the sampling phase angle.

That is, by the addition addition time calculator 31 as the addition addition time calculation means shown in FIG. 3, a closing instruction is given to the transformer primary side circuit breaker 6 by a closing phase angle of a specific phase set in advance and a closing instruction. The addition time is calculated from the closing time which is the shortest time among the time difference between the time when the transformer primary breaker 6 is actually turned on and the transformer primary breaker 6 is turned on. When a command is received, VB (a), VB (b), VB (c): instantaneous value of bus voltage, Vm: maximum value of bus voltage, θ: specific Phase angle of phase, VB: When the instantaneous value of the bus voltage of a specific phase
Thus, the first input phase angle calculator 78 serving as the first input phase angle calculation means obtains the input phase angle at the time of the first sampling at the time of receiving the input command by the sin ⁻¹ phase angle method, and the second input phase angle A second input phase angle calculator 79 serving as a calculation means obtains the input phase phase angle at the time of the second sampling at the time of receiving the input command by the sin ⁻¹ phase angle method. Then, the first reference phase angle calculator 78 calculates the first input phase angle calculator 78 from the input phase angle at the time of the second sampling determined by the second input phase angle calculator 79 by the input reference point detector 71 serving as the input reference point detector. The input phase angle change width obtained by subtracting the input phase angle at the time of sampling 1 is larger than the sampling time width expressed by the phase angle obtained by subtracting the first sampling time from the second sampling time. A value smaller than twice the time width is set as the input reference point. Then, a loading reference time is calculated from the loading reference point detected by the loading reference point detector 71 by a loading reference time calculator 34 serving as a loading reference time calculating means. Then, the charging reference time calculated by the charging reference time calculator 34 by the charging command output device 36 as the charging command means and the charging addition time calculated by the charging addition time calculator 31 as the charging addition time calculating means. The sum is used as the input waiting time, and an input command is given to the transformer primary circuit breaker 6 after the input waiting time has elapsed.

  FIG. 17 is a time chart showing the charging control of the three-phase AC transformer 2. In FIG. 17, the work θ to be executed in non-real time is the closing phase angle of the closing phase obtained by the optimum closing phase angle calculator 28 serving as the closing phase angle calculating means, and the closing time becomes the closing time changing means. This is the latest charging time of the transformer primary circuit breaker 6 overwritten by the transformer charging time overwrite unit 53.

  As an example, assuming that the input phase angle (θ) = 60 degrees and the input time is 66.7 ms, the input phase angle is 20 samplings and the input time is 400 counts if the sampling count is corrected. Accordingly, the addition time is 100 counts.

As a work to be executed in real time, the first sampling phase angle calculation result obtained by the first input phase angle calculator 78 which receives the input command and is the first input phase angle calculation means is θ _1, and the second input The next second sampling phase angle calculation result obtained by the second input phase angle calculator 79 serving as the phase angle calculation means is θ _2, and the phase angle change of the value is larger than the sampling time width and twice the sampling width. Using the smaller value as the reference point for input, the input reference time is obtained.

  As an example, if the input reference point obtained by the input reference point detector 71 is 30 degrees, the number of sampling counts is 10 counts, so the input reference time calculator 34 calculates 110 counts.

  Therefore, since the insertion waiting time calculator 35 is the sum of the addition addition time and the input reference time, the insertion waiting time is calculated as 210 counts.

  Thus, after 210 counts from the start of the closing reference point detector 71, the closing command 70 is delivered to the closing command output device 36, and the closing time of the transformer primary side circuit breaker 6 has elapsed and the transformer The primary side circuit breaker 6 is turned on.

  As the input reference point detector 71 shown in FIG. 3, an overvoltage detector 47 is provided in the detection transformer 7 and its operation is used as a detection point. That is, the time when the transformer primary circuit breaker 6 is actually turned on is the detection voltage of the detection transformer 7 which is the secondary voltage change of the transformer primary circuit breaker 6 of the three-phase AC transformer 2. This is the time when the change is detected by the overvoltage detector 47.

  FIG. 18 is a graph showing a state in which the closing time is detected by the closing reference point detector 71, where the horizontal axis represents the sampling count and the vertical axis represents the voltage (pu). 72 and 73 are detection setting voltages of the overvoltage detector 47, and are set to ± 0.05 (pu) here. 74 is a transformer voltage detected by the detection transformer 7. Then, the time when the transformer voltage 74 first reaches the detection setting voltages 72 and 73 of the overvoltage detector 47 is detected as the closing time 75.

  The charging time is measured by a transformer charging time detector 76 shown in FIG. As for the closing time when the three-phase AC transformer 2 is turned on, the closing time measured in the repair record is a no-voltage opening time, so it is necessary to consider the pre-arc time. The transformer turn-on time detector 76 based on the learning function of the learning device 52 can measure the turn-on time in consideration of the pre-arc time when the time difference between the high-speed turn-on command detector 20 and the turn-on reference point detector 71 shown in FIG. . FIG. 19 is a diagram showing an example of the charging time detected by the transformer charging time detector 76. In FIG. In FIG. 19, the horizontal axis represents the phase angle (degrees) and the vertical axis represents the voltage (pu).

  The closing time of the transformer primary circuit breaker 6 is overwritten to the previous charging time as the latest charging time by the transformer charging time overwrite unit 53 serving as switching time changing means, and the monitoring control screen 48 shown in FIG. The operation time (input time) is displayed in the operation time field of the input field 48b2 of the cutoff input command value field 48b.

  The making phase angle setting unit 77 serving as the making phase angle calculating means shown in FIG. 3 Fourier-transforms the bus voltage data for one cycle before the sampling from the making time 75 shown in FIG. 18 detected by the making reference point detector 71. To extract the fundamental wave, add one sampling to the phase angle, and measure the input phase angle.

In FIG. 21, the phase angle of the bus voltage is calculated with a sin ⁻¹ phase angle detector, the phase angle is further calculated with the next sampling value, and the change width is detected to be twice or less the sampling phase angle. It is a time chart explaining a mode.

Here, the horizontal axis represents time in units of phase angle, and the vertical axis represents the phase angle obtained by a sin ⁻¹ phase angle detector. From this figure, the phase angle at time -9 degrees is -12 degrees, the phase angle at time -6 degrees, which is the next sampling value, is -3 degrees, the difference is 9 degrees and deviates from the above judgment condition. ing.

  Since the phase angle at the next sampling time of -3 degrees is +2.5 degrees, the difference is 5.5 degrees, which satisfies the above judgment condition. The ejector 71 responds.

  The phase angle of each phase bus voltage at the time when the transformer primary-side circuit breaker 6 is actually turned on is displayed by the display section 38 serving as a display means, as shown in FIG. Is displayed in the breaking / closing phase angle field 48c3 of the closing column 48c4, and the bus effective value voltage before the predetermined time and the bus effective value voltage until the predetermined time after the time when the transformer primary side circuit breaker 6 is actually turned on. The instantaneous voltage drop amount which is the difference from the minimum value is displayed in the instantaneous voltage drop amount column 48d5 of the confirmation display column 48d of the monitor control screen 48 shown in FIG. 5, and the latest input time is shown in the monitor control screen 48 shown in FIG. It is displayed in the operation time column of the input column 48b2 of the cutoff input command value column 48b.

  As an application example of the present invention, a transformer excitation inrush current suppression control method and a transformer excitation inrush current suppression for suppressing an excitation inrush current generated when a transformer is connected to a power system including harmonics are used. It can be applied to a control device.

DESCRIPTION OF SYMBOLS 1 ... Main circuit, 2 ... Three-phase alternating current transformer, 3 ... Circuit breaker operation switch, 4 ... Busbar, 5 ... Bus voltage detection transformer (VT-1), 6 ... Transformer primary side circuit breaker (CB -1), 7 ... Detection transformer (VT-2), 8 ... Transformer secondary circuit breaker (CB-2), 9 ... Breaking operation switch, 10 ... Operation switch, 11 ... Transformer excitation Inrush current suppression control device, 12 ... control unit, 13, 14 ... input converter, 15, 16 ... auxiliary device, 17,18 ... switching circuit, 19 ... high speed shut-off command detector, 20 ... high speed turn-on command detector, 21 ... Circuit breaker operation circuit, 22 ... Trip coil, 23 ... Closing coil, 24 ... Auxiliary switch, 25 ... Transformer break time detector, 26 ... Residual magnetic flux measuring device, 27 ... Input phase setter, 28 ... Transformer break Time override unit, 29 ... Virtual inrush current calculator, 30 ... Transformer input device, 31 ... Input addition time calculator, 32 ... Reception phase angle calculator, 33 ... nth-order phase angle calculator, 34 ... Input reference time Calculation , 35 ... closing time calculator, 36 ... closing command output device, 37 ... closing time setter, 38 ... display unit, 39 ... cutoff phase angle setter, 40 ... cutoff addition time calculator, 41 ... cutoff reference time Operation unit 42 ... Interruptation waiting time operation unit 43 ... Interrupt command output device 44 ... Interrupt time setting device 45 ... Transformer setting input device 46 ... Setting input screen 46a ... Frequency selection field 46a1 ... List button 46b ... Transformer tap voltage column, 46c ... Transformer connection column, 46d ... Transformer voltage capture location column, 47 ... Overvoltage detector, 48 ... Monitoring control screen, 48a ... Setting button, 48b ... Shut-off input command value column, 48b1 ... cutoff field, 48b2 ... input field, 48c ... cutoff input actual measurement value field, 48c1 ... cutoff field, 48c2 ... operating time field, 48c3 ... cutoff / on phase angle field, 48c4 ... input field, 48d ... confirmation display field, 48d1 ... Residual magnetic flux column, 48d2 ... Optimal control column, 48d3 ... Interrupt column, 48d4 ... Put-on column, 48d5 ... Momentary voltage drop column, 49 ... Put-on setting Screen, 50 ... Shut-off setting screen, 49a, 50a ... Control phase column, 49b, 50b ... Phase angle column, 49c, 50c ... Decision button, 51 ... Transformer shut-off learning device, 52 ... Transformer turn-on learning device, 53 ... Transformer Overload device, 54 ... Optimum operation calculator, 55, 56 ... Transformer cut-off zone, 57 ... Operation time, 58 ... Phase angle detection time, 59 ... Cut-off command output time, 60 ... Change width phase angle detector, 61 ... sin ^-1 phase angle detector, 62 ... cutoff reference point detector, 63, 64 ... detection set voltage, 66 ... differential voltage, 67 ... cutoff time, 68 ... operating time, 69 ... phase angle detection time, 70 ... Input command output time, 71 ... Reference point detector, 72, 73 ... Detection set voltage, 74 ... Transformer voltage, 75 ... Input time, 76 ... Transformer input time detector, 77 ... Input phase angle setter, 78 ... 1st closing phase angle calculator, 79 ... 2nd closing phase angle calculator, 81 ... 1st cutoff phase angle calculator, 82 ... 2nd cutoff phase angle calculator, 83 ... Shutdown reference check Vessel, 84 ... blocking reference time calculator, 94 ... fundamental wave extractor

Claims (22)

A method for controlling the insertion of a circuit breaker provided at a terminal of a three-phase AC transformer provided in a power system including harmonics ,
From the closing phase angle of the specific phase set in advance, the time when the closing command is given to the circuit breaker by the closing command, and the closing time which is the shortest time among the time difference between when the circuit breaker is actually turned on Find the input addition time,
When receiving the circuit breaker input command, from the instantaneous value of the bus voltage sampled at the time of reception,
VB (a), VB (b), VB (c): instantaneous value of the bus voltage,
Vm: maximum value of the bus voltage,
θ: phase angle of a specific phase,
VB: instantaneous value of the bus voltage of a specific phase,
When
To determine the input phase phase angle at the time of the first sampling by the sin ⁻¹ phase angle method at the time of receiving the input command, and to determine the input phase phase angle at the time of the second sampling by the sin ⁻¹ phase angle method. The input phase angle change width obtained by subtracting the input phase angle at the first sampling from the input phase angle at the time of sampling represents the time obtained by subtracting the first sampling time from the second sampling time. A value larger than the sampling time width and smaller than twice the sampling time width is set as the input reference point, and the sum with the input addition time is set as the input waiting time. A transformer excitation inrush current suppression control method characterized by: 2. The transformer according to claim 1 , wherein by the transformer inrush current suppression method according to claim 1 , the last turn-on time is overwritten on the last turn-on time as the latest turn-on time. Method for controlling the inrush current of a magnet. The phase angle of each phase bus voltage at the time when the circuit breaker inserted by the transformer excitation inrush current suppression method according to claim 1 is actually turned on, and the transformer excitation inrush current according to claim 1 An instantaneous voltage drop amount that is a difference between a bus effective value voltage before a predetermined time and a minimum value of the bus effective value voltage after a predetermined time after the time when the circuit breaker input by the suppression method is actually applied; and 2. A transformer excitation inrush current suppression control method, wherein at least one of the latest input times described in 2 is displayed. The time at which the circuit breaker is actually turned on, transformer according to claim 1, characterized in that the overvoltage detector secondary voltage changes in the circuit breaker of the three-phase AC transformer is the time of detection Excitation current suppression control method. The fundamental wave is extracted by Fourier expansion of the bus voltage data for one cycle from one sampling before the input time detected by the overvoltage detector, and the value obtained by adding the phase angle for one sampling to the phase angle of the fundamental wave The transformer excitation inrush current suppression control method according to claim 4 , wherein the input phase angle of the three-phase AC transformer is set. A device for controlling the insertion of a circuit breaker provided at a terminal of a three-phase AC transformer provided in a power system including harmonics ,
From the closing phase angle of the specific phase set in advance, the time when the closing command is given to the circuit breaker by the closing command, and the closing time which is the shortest time among the time difference between when the circuit breaker is actually turned on A charge addition time calculating means for obtaining a charge addition time;
When receiving the circuit breaker input command, from the instantaneous value of the bus voltage sampled at the time of reception,
VB (a), VB (b), VB (c): instantaneous value of the bus voltage,
Vm: maximum value of the bus voltage,
θ: phase angle of a specific phase,
VB: instantaneous value of the bus voltage of a specific phase,
When
The first input phase angle calculating means for obtaining the input phase angle at the time of the first sampling by the sin ⁻¹ phase angle method when receiving the input command,
Second closing phase angle calculating means for obtaining a closing phase angle at the time of the second sampling at the time of receiving the closing command by a sin ⁻¹ phase angle method;
An input phase angle change width obtained by subtracting the input phase angle at the first sampling obtained by the first input phase angle calculating means from the input phase angle at the second sampling time obtained by the second input phase angle calculating means. An input reference having an input reference point having a value larger than a sampling time width expressed by a phase angle obtained by subtracting the first sampling time from the second sampling time and smaller than twice the sampling time width Point detection means;
Input reference time calculating means for calculating the input reference time from the input reference point detected by the input reference point detecting means,
The sum of the input reference time calculated by the input reference time calculating means and the input addition time calculated by the input addition time calculating means is set as an input waiting time, and after the input waiting time has elapsed, an input command is given to the circuit breaker. Input command means;
A transformer excitation inrush current suppression control device characterized by comprising: 7. A turn-on time changing means for overwriting the last turn-on time with the turn-on time of the circuit breaker thrown in by the transformer excitation inrush current suppressing device according to claim 6 as the latest turn-on time. 6. The transformer excitation inrush current suppression control device according to 6. The phase angle of each phase bus voltage at the time when the circuit breaker introduced by the transformer excitation inrush current suppression device according to claim 6 is actually turned on, and the transformer excitation inrush current according to claim 6 An instantaneous voltage drop amount, which is a difference between a bus effective value voltage before a predetermined time and a minimum value of the bus effective value voltage after a predetermined time after the time when the circuit breaker supplied by the suppression device is actually turned on; and 7. A transformer excitation inrush current suppression control device comprising display means for displaying at least one of the latest input times described in 7 . The transformer according to claim 6 , wherein the time when the circuit breaker is actually turned on is the time when the overvoltage detector detects a change in the secondary voltage of the circuit breaker of the three-phase AC transformer. Excitation current suppression control device. Fundamental wave extraction means for extracting a fundamental wave by Fourier-developing the bus voltage data for one cycle from one sampling before the input time detected by the overvoltage detector;
Closing phase angle setting means for setting a value obtained by adding a phase angle for one sampling to the phase angle of the fundamental wave extracted by the fundamental wave extracting means as the closing phase angle of the three-phase AC transformer;
The transformer excitation inrush current suppression control device according to claim 9 , wherein A method for controlling the breaking of a circuit breaker provided at a terminal of a three-phase AC transformer,
Φ m: maximum residual magnetic flux,
Φr (a), Φr (b), Φr (c): residual magnetic flux of each phase,
When
Φ r (a) = Φ m
Φ r (b) = − Φ m / 2
Φ r (c) = − Φ m / 2
A transformer excitation inrush current suppression control method characterized in that the transformer has a cutoff phase angle satisfying A method for controlling the breaking of a circuit breaker provided at a terminal of a three-phase AC transformer,
From the breaking time which is the shortest time among the time difference between the breaking phase angle of a specific phase set in advance, the time when the breaking command is given to the breaker by the breaking command, and the time when the breaker is actually broken Find the cutoff addition phase angle,
When receiving the breaker command of the breaker, from the instantaneous value of the bus voltage sampled at the time of reception,
VB (a), VB (b), VB (c): instantaneous value of bus voltage,
Vm: maximum value of the bus voltage,
θ: phase angle of a specific phase,
VB: instantaneous value of the bus voltage of a specific phase,
When
The cutoff phase phase angle at the time of the first sampling is obtained by the sin ⁻¹ phase angle method when the cutoff command is received, and the cutoff phase phase angle at the time of the second sampling is obtained by the sin ⁻¹ phase angle method. The change width of the cut-off phase angle obtained by subtracting the cut-off phase angle at the time of the first sampling from the cut-off phase angle at the time of sampling represents the time obtained by subtracting the first sampling time from the second sampling time. A value larger than the sampling time width and smaller than twice the sampling time width is set as a cutoff reference point, and the sum with the cutoff addition time is set as a cutoff waiting time. A transformer excitation inrush current suppression control method characterized by: According to claim 1 2 has been cut off time of the circuit breaker blocked by to transformer magnetizing inrush current suppression method according to the claim 1 2, characterized in that overwriting the previous interruption time as the latest breaking time Transformer excitation inrush current suppression control method. The time when the circuit breaker was actually cut off was the time when the overvoltage detector detected a difference voltage change between the bus voltage of the three-phase AC transformer and the detected voltage of the transformer for detecting the bus voltage. The transformer excitation inrush current suppression control method according to claim 12 , wherein the transformer excitation inrush current is suppressed. The fundamental voltage is extracted by performing Fourier expansion on the bus voltage data for one cycle from one sampling before the cutoff time detected by the overvoltage detector, and the value obtained by adding the phase angle for one sampling to the phase angle of the fundamental wave transformer magnetizing inrush current suppression control method according to claim 1 4, characterized in that the shutoff phase angle of the three-phase AC transformer. And phase angle of each phase bus voltage in claim 1 2 to transformer time magnetizing inrush current suppression circuit breaker, which is blocked by the process is actually cut off according to the latest blocking according to claim 1 3 A transformer excitation inrush current suppression control method, wherein at least one of the times is displayed. A device for controlling the breaking of a circuit breaker provided at a terminal of a three-phase AC transformer,
Φ m: maximum residual magnetic flux,
Φr (a), Φr (b), Φr (c): residual magnetic flux of each phase,
When
Φ r (a) = Φ m
Φ r (b) = − Φ m / 2
Φ r (c) = − Φ m / 2
A transformer excitation inrush current suppression control device, comprising: a cutoff phase angle calculation means for calculating a cutoff phase angle of the three-phase AC transformer that satisfies the above. A device for controlling the breaking of a circuit breaker provided at a terminal of a three-phase AC transformer,
From the breaking time which is the shortest time among the time difference between the breaking phase angle of a specific phase set in advance, the time when the breaking command is given to the breaker by the breaking command, and the time when the breaker is actually broken An interruption addition phase angle calculating means for obtaining an interruption addition phase angle;
When receiving the breaker command of the breaker, from the instantaneous value of the bus voltage sampled at the time of reception,
VB (a), VB (b), VB (c): instantaneous value of the bus voltage,
Vm: maximum value of the bus voltage,
θ: phase angle of a specific phase,
VB: instantaneous value of the bus voltage of a specific phase,
When
The first cutoff phase angle calculation means for obtaining the cutoff phase phase angle at the time of the first sampling by the sin ⁻¹ phase angle method when the cutoff command is received,
A second cutoff phase angle calculating means for obtaining a cutoff phase phase angle at the time of the second sampling at the time of receiving the cutoff command by a sin ⁻¹ phase angle method;
A cut-off phase angle change width obtained by subtracting the cut-off phase angle at the first sampling obtained by the first cut-off phase angle calculating unit from the cut-off phase angle at the second sampling obtained by the second cut-off phase angle calculating unit. A cutoff reference having a cutoff reference point with a value larger than a sampling time width expressed by a phase angle obtained by subtracting the first sampling time from the second sampling time and smaller than twice the sampling time width. Point detection means;
An interruption reference time calculating means for calculating an interruption reference time from the interruption reference point detected by the interruption reference point detecting means;
The sum of the cutoff reference time calculated by the cutoff reference time calculation means and the cutoff addition time calculated by the cutoff addition time calculation means is set as a cutoff waiting time, and a cutoff command is given to the breaker after the cutoff waiting time has elapsed. Shut-off command means;
A transformer excitation inrush current suppression control device characterized by comprising: 19. A break time changing means for overwriting the previous break time as the latest break time with the break time of the breaker interrupted by the transformer magnetizing inrush current suppressing device according to claim 18. 18. The transformer excitation inrush current suppression control device according to 18 . The time when the circuit breaker was actually cut off was the time when the overvoltage detector detected a difference voltage change between the bus voltage of the three-phase AC transformer and the detected voltage of the transformer for detecting the bus voltage. The transformer excitation inrush current suppression control device according to claim 18 , wherein Fundamental wave extraction means for extracting a fundamental wave by performing Fourier expansion of the bus voltage data for one cycle from one sampling before the cutoff time detected by the overvoltage detector;
Cutoff phase angle setting means for setting a value obtained by adding a phase angle for one sampling to the phase angle of the fundamental wave extracted by the fundamental wave extraction means as the cutoff phase angle of the three-phase AC transformer;
Transformer magnetizing inrush current suppression control system of claim 2 0, characterized in that it comprises a. The phase angle of each phase bus voltage at the time when the circuit breaker interrupted by the transformer excitation inrush current suppression device according to claim 18 is actually interrupted, and the latest interrupting time according to claim 19 A transformer excitation inrush current suppression control device comprising display means for displaying at least one of them.