JP3189541B2 - Abnormality monitoring device for load tap changer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load tap changer abnormality monitoring apparatus for monitoring an abnormality of a load tap changer and preventing an accident from occurring.

[0002]

2. Description of the Related Art Generally, an on-load tap changer is provided in an on-load tap change transformer when a load of a power transmission and distribution system fluctuates and a voltage change corresponding to the change exceeds a predetermined value. By switching the tap, the voltage of the power transmission and distribution system is kept constant. Therefore, if the load tap changer in the transmission and distribution system fails, there is a risk of a power failure over a wide range. Therefore, an abnormality monitoring device that can detect a sign of the failure and prevent a serious accident from occurring has been proposed. I have.

FIG. 3 is a configuration diagram of a conventional abnormality monitoring apparatus for a tap changer under load described in Japanese Patent Publication No. 4-39664. In FIG. 3, reference numeral 1 denotes a switching signal generator for outputting a switching signal for tap switching, and 2 denotes a motor operating mechanism, which is driven by a motor (not shown). Reference numeral 3 denotes a load tap changer, and reference numeral 4 denotes a changeover detection unit for detecting a changeover start signal, which sends a detection signal to an abnormality determination unit 6 described later.

Reference numeral 5 denotes a torque detecting unit which detects a torque applied to a drive shaft of the tap changer 3 under load. Reference numeral 6 denotes an abnormality determination unit which performs an operation comparison between a normal torque characteristic pattern stored in a storage circuit unit 7 described later and an operation torque characteristic pattern detected by the torque detection unit 5 during operation of the on-load tap changer 3. To determine whether it is abnormal. Reference numeral 7 denotes a storage circuit for storing a normal torque characteristic pattern during a normal switching operation, and reference numeral 8 denotes a display circuit.

In the above configuration, when a tap switching signal is output from the switching signal generator 1, the switching detector 4 detects a tap switching signal for starting switching and sends a detection signal to the abnormality determiner 6. On the other hand, the electric motor of the electric motor operating mechanism 2 is driven by the tap switching signal output from the switching signal generating unit 1, and the on-load tap switching device 3 operates to apply torque to the drive shaft 2a. The torque detector 5 detects the torque applied to the drive shaft 2 a of the on-load tap changer 3, and sends a detection signal to the abnormality determiner 6.

The abnormality judging section 6 compares the normal torque characteristic pattern of the storage circuit 7 with the operating torque characteristic pattern at the time of switching detected by the torque detecting section 5, and judges the sign of the failure and the failure from the difference. The determination result is output to the display circuit 8. In addition, at the time of testing the on-load tap changer 3, the drive shaft 2a can be driven manually via the motor operating mechanism 2.

Further, in order to prevent an accident of the load tap changer before it occurs, an abnormality monitoring device has been put to practical use which monitors the tap change time as a physical quantity generated during the changeover operation and detects a sign of an abnormality. . By monitoring the tap switching time, it is possible to detect an abnormality in the control circuit of the motor operating mechanism, which accounts for a large proportion of accidents of the on-load tap changer.

FIG. 4 is a very general control circuit diagram of a motor operating mechanism for driving a load tap changer. FIG.
In the figure, 9 is an electric motor for driving, 10 is an ascending electromagnetic contactor for switching the tap to the ascending side, and is composed of a coil 10a, normally open contacts 10b, 10c, 10d and a normally closed contact 10e. Reference numeral 11 denotes a descending electromagnetic contactor for switching a tap to a descending side, and a coil 11a and a normally open contact 11b,
11c and 11d and a normally closed contact 11e. Reference numeral 12 denotes a braking electromagnetic contactor that short-circuits the terminals of the motor 9 to apply a brake to the motor 9, and includes a coil 12a, a normally open contact 12b, and a normally closed contact 12c.

Reference numeral 13 denotes a pilot cam switch mounted on the shaft of the tap changer, which closes during the switching operation between taps, and opens at the tap position. Reference numeral 14 denotes an ascending switch command switch for instructing ascending switching, which is operated by a commander. Fifteen
Is a down switch command switch for instructing a down switch, which is operated by a commander. Reference numeral 16 denotes a current detector for detecting the current of the electric motor 9, and outputs a current detection signal 16a.

3 and 4, when the ascending switch 14 is closed by a commander, the coil 10a of the ascending electromagnetic contactor 10 is energized and the normally open contact 10 is turned on.
b, 10c, and 10d are closed, and the normally closed contact 10e is opened. Therefore, the coil 12 of the electromagnetic contactor 12 for braking
a is excited via the contact 10d, the normally open contact 12b is closed, and the normally closed contact 12c is opened. By closing the contacts 10b and 12b, the electric motor 9 is driven by being supplied with power from a power supply.

As a result, the drive shaft of the on-load tap changer 3 is rotated via the motor operating mechanism 2, and the tap change operation is started. The pilot cam switch 13 is closed between taps during the tap change operation. Therefore, even if the ascending switching command switch 14 is opened, the coil 10a is excited via the pilot cam switch 13 and the contact 10c, so that the motor 9 continues to rotate and the drive shaft 2a is reliably fed to the next tap. .

In such a configuration, when monitoring the tap switching time and judging an abnormality, the current of the electric motor 9 is measured by the current detector 16 and the operation is started from the current continuation time, or the ascending electromagnetic contactor 10 or Descending electromagnetic contactor 11
It has been done to measure the injection time.

However, this measured value differs from tens of percent to tens of percent depending on the switching direction immediately before switching even when normal tap switching is performed. That is, in the case where the switching is performed immediately before the switching and the switching is performed this time, and in the case where the switching is performed in the reverse direction where the switching direction immediately before the switching is different from the current switching direction, the switching time of the latter is more than tens of% to several 10% longer.

Therefore, an abnormality monitoring device that detects an abnormality at a minor stage by monitoring the switching direction and making an abnormality judgment by focusing on the switching time difference depending on the switching mode of the same direction switching or the reverse direction switching has also been commercialized. Have been. In this case, the switching direction is determined based on the operation state of the ascending switch command switch 14 or the descending switch command switch 15 in FIG.

[0015]

SUMMARY OF THE INVENTION A conventional abnormality monitoring device for a tap changer under load monitors the duration of the current of a drive motor or the operation of an ascending or descending electromagnetic contactor. Therefore, the switching direction at the time of manual driving cannot be detected. Therefore, when the motor is driven after the manual drive, the abnormality determination may be erroneously made because the switching direction before the motor drive is unknown.

That is, an abnormal alarm may be issued in spite of normal operation, or it may be determined that the operation is normal even if the operation is abnormal.
If an erroneous determination is made, an investigation of the cause is troublesome and requires a great deal of time and labor. The manual drive is a necessary operation for checking when an abnormality is detected, performing a periodic inspection, and the like.

The present invention has been made in order to solve the above problems, and provides an abnormality monitoring device for a load tap changer that detects manual driving and determines abnormality.

[0018]

SUMMARY OF THE INVENTION According to the present invention, there is provided an abnormality monitoring apparatus for a load tap changer which detects a drive signal when an electric motor is driven, and detects an operation signal when an operation mechanism is activated. An operation signal detecting means for detecting, and when the drive signal and the operation signal are detected, the motor drive is stored as being driven by the motor, and when only the operation signal is detected, the manual drive is stored as being manually driven. Storage means; and arithmetic processing means for performing a process of ignoring the abnormality diagnosis of the on-load tap changer only once when the motor drive is detected next to the manual drive stored in the storage means. .

Further, drive signal detecting means for detecting a drive signal when the electric motor is driven, operation signal detecting means for detecting an operation signal when the operating mechanism is operated, and detecting an insertion signal when the handlebar crank is inserted. Insertion signal detection means, and when the drive signal and the operation signal are detected, the motor drive is stored as being driven by the motor when detected, and the drive is manually driven when the operation signal and the insertion signal are detected. Storage means for storing, and arithmetic processing means for performing a process of ignoring the abnormality diagnosis of the on-load tap changer only once when the motor drive is detected next to the manual drive stored in the storage means It is.

[0020]

According to the present invention, when the motor is driven, the drive signal is detected by the drive signal detecting means, and when the operating mechanism is operated, the operation signal is detected by the operation signal detecting means, and the drive signal and the operation signal are detected. It is stored in the motor drive and the storage means as being driven by the motor when the operation is performed, and further, when only the operation signal is detected, the manual drive and the storage means are stored.The manual drive stored in the storage means is followed by the motor drive. When a fault is detected, the fault diagnosis is performed once, ignoring the fault diagnosis only once.

When the motor is driven, the drive signal is detected by the drive signal detecting means, and when the operating mechanism is operated, the operating signal is detected by the operating signal detecting means, and a handle crank for manually operating the operating mechanism is inserted. When the insertion signal is detected, the insertion signal is detected by the insertion signal detection means. When the drive signal and the operation signal are detected, the insertion signal is stored in the motor drive and storage means as being driven by the motor, and the operation signal and the insertion signal are detected. When this is done, the manual drive is stored in the storage means, and when the motor drive is detected next to the manual drive stored in the storage means, the abnormality diagnosis is ignored once, ignoring the abnormality diagnosis only once.

[0022]

【Example】

Embodiment 1 FIG. FIG. 1 is a configuration diagram of an abnormality monitoring device for a tap changer under load according to the present invention. In FIG. 1, reference numeral 17 denotes a tap selector which is deviated from one tap and supplied to the other tap by a switching signal when a voltage change exceeds a predetermined limit. Reference numeral 18 denotes a switching switch, which performs a switching operation from one tap to the other tap corresponding to the tap selector 17.
19 is a converter. Tap selector 17 and switching switch 1
The on-load tap changer 20 is composed of the converter 8 and the converter 19. Reference numeral 21 denotes an operation mechanism using the electric motor 9 as a drive source, and an insertion shaft 2 into which a manually driven handle crank 22 can be inserted.
1a is provided.

Reference numeral 23 denotes a drive shaft, which is a motor 9 of the operating mechanism 21.
Is transmitted to the tap changer 20 under load. Reference numeral 24 denotes a torque detector attached to the drive shaft 23, and outputs a torque detection signal 24a. Reference numeral 25 denotes a tap switching signal generating means which outputs a tap switching signal 25a to instruct a signal conversion means 28 to be described later to start abnormality diagnosis, and also sends a signal to the digital input interface 27. Reference numeral 26 denotes a tap position signal generating means for generating a tap position signal 26a according to a change in the tap position. Reference numeral 27 denotes a digital input interface, which is a tap switching signal 25a and a tap position signal 26a.
a is converted into a digital signal and output to the arithmetic processing means 31 described later.

Reference numeral 28 denotes a signal converting means which receives the tap switching signal 25a which is a command to start measurement of abnormality diagnosis, and converts the current detection signal 16a and the torque detection signal 24a into electric analog signals having predetermined values. Reference numeral 29 denotes an A / D converter, which converts an analog signal from the signal converter 28 into a digital signal and outputs the digital signal to an arithmetic processing unit 31 described later.

Numeral 30 is a storage means, which uses the current detection signal 16a or the tap switching signal 25a as a drive signal, the torque detection signal 24a or the tap position signal 26a as an operation signal, and detects the motor 9 when the drive signal and the operation signal are detected. Is stored as the drive by the motor, and is stored as the manual drive as the one driven manually when only the operation signal is detected. Further, an abnormality determination criterion for the operation mode and various data are stored.

Numeral 31 denotes an arithmetic processing means which constantly monitors a current detection signal 16a or a tap switching signal 25a as a drive signal and a torque detection signal 24a or a tap position signal 26a as an operation signal. Then, when only the operation signal is detected without detecting the drive signal, the operation is compared with the contents of the storage means 30 to determine that the drive is manual. When a drive signal and an operation signal are detected, it is determined that the motor is driven.

Further, if the previous tap switching operation is determined to be manual drive and stored, and if the next tap switching operation is determined to be motor drive, only the tap position is stored and no abnormality diagnosis is performed. . Subsequently, when it is determined that the motor is driven, the subsequent abnormality diagnosis is performed. Reference numeral 32 denotes an output unit that outputs an abnormality alarm or the like.

In FIG. 1, when the motor 9 is driven by the tap switching signal, a current detection signal 16a and a tap switching signal 25a of the driving signal are detected. Then, a torque detector 24 attached to the drive shaft 23 detects the torque detection signal 24a as an operation signal. Further, the tap position signal generating means 26 detects a change in the tap position using the tap position signal 26a as an operation signal. However, the drive signal may be only one of the current detection signal 16a and the tap switching signal 25a, and the operation signal may be only one of the torque detection signal 24a and the tap position signal 26a.
Further, the drive signal may be an operation signal when the electromagnetic contactor 10 shown in FIG. 4 operates.

Embodiment 2 FIG. FIG. 2 is a configuration diagram showing another embodiment. In FIG. 2, reference numeral 33 denotes a handle switch, which outputs an insertion signal 33a when the handle crank 22 is inserted into the insertion shaft 21a of the operation mechanism 21 to a digital input interface 34 described later. Reference numeral 34 denotes a digital input interface, which converts the tap switching signal 25a, the tap position signal 26a, and the insertion signal 33a into digital signals and outputs the digital signals to the arithmetic processing means 36 described later.

Numeral 35 is a storage means, which uses the current detection signal 16a or the tap switching signal 25a as a drive signal, the torque detection signal 24a or the tap position signal 26a as an operation signal, and detects the motor 9 when the drive signal and the operation signal are detected. Is stored as driving by the motor, and is stored as manual driving as being driven manually when the operation signal and the insertion signal 33a are detected.

Numeral 36 denotes an arithmetic processing means, which is a current detection signal 16a or a tap switching signal 25a as a drive signal, a torque detection signal 24a or a tap position signal 26a as an operation signal, and an insertion signal 33a when the handle crank 22 is inserted. And is constantly monitored. When the drive signal and the operation signal are detected, the drive is compared with the contents of the storage means 35 to determine that the motor is driven. When the operation signal and the insertion signal 33a are detected, the operation is determined to be manual driving by comparing the contents of the storage means 35.

Further, if the previous tap switching operation is determined to be manual drive and stored, and if the next tap switching operation is determined to be motor driven, only the tap position is stored and no abnormality diagnosis is performed. . Subsequently, when it is determined that the motor is driven, the subsequent abnormality diagnosis is performed.

Embodiment 3 FIG. In the second embodiment, the manual drive is performed when the operation signal and the insertion signal 33a are detected.
It is also possible to detect only the insertion signal 33a and determine that the driving is manual.

[0034]

As described above, according to the present invention, when the drive signal and the operation signal are detected, they are stored in the motor drive and storage means, and when only the operation signal is detected, they are stored in the manual drive and storage means. Since the abnormality diagnosis is ignored only once when the motor drive is detected after the manual drive stored in the storage means, erroneous determination of the abnormality diagnosis can be prevented even if the switching direction by the manual drive is unknown.

Further, when the drive signal and the operation signal are detected, it is stored in the motor drive and storage means, and when the operation signal and the insertion signal are detected, the manual drive and the storage means are stored, and the stored manual drive is stored. Next, when the motor drive is detected, the abnormality diagnosis is ignored only once, so that erroneous determination of the abnormality diagnosis can be prevented even if the switching direction by manual drive is unknown.

Further, when the drive signal and the operation signal are detected, the data is stored in the motor drive and storage means, and when only the insertion signal is detected, the data is stored in the manual drive and storage means. Since the abnormality diagnosis is ignored only once when the motor drive is detected, it is possible to prevent erroneous determination of the abnormality diagnosis with a simple configuration even if the switching direction by manual drive is unknown.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a load tap changer abnormality monitoring device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing another embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional abnormality monitoring device for a load tap changer.

FIG. 4 is a general control circuit diagram of a motor operating mechanism that drives a load tap changer.

[Explanation of symbols]

Reference Signs List 16 Current detector (drive signal detecting means) 17 Tap selector 18 Switching switch 20 Tap switch at load 21 Operating mechanism 22 Handle crank 24 Torque detector (operation signal detecting means) 25 Tap switching detection signal generating means (drive signal) detecting means) 26 tap position detection signal generating means (actuation signal detecting means) 30, 3 5 storage means 31,3 6 processing means 33 handle switch (insertion signal detecting means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Showa 59-155612 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01F 29/04 G01R 31/00 H02H 7 / 055

Claims (8)

(57) [Claims] 1. An on-load tap changer in which a changeover switch and a tap selector are operated by an electric motor via an operation mechanism or manually operated via the operation mechanism to perform a tap change operation. In an abnormality monitoring device of a load tap changer that monitors an operation state and detects an abnormality, a drive signal detection unit that detects a drive signal when the electric motor is driven,
An operation signal detecting means for detecting an operation signal when the operation mechanism is operated; and, when detecting the drive signal and the operation signal, storing as an electric motor drive as being driven by the electric motor and detecting only the operation signal Storage means for storing the manual drive as being manually driven when the motor drive is detected, and when the motor drive is detected next to the manual drive stored in the storage means, the abnormality diagnosis of the on-load tap changer is performed by 1 An abnormality monitoring device for an on-load tap changer, comprising: an arithmetic processing means for performing a process of ignoring only once. 2. A tap switching operation is performed by operating a switching switch and a tap selector by an electric motor via an operation mechanism or by inserting and operating a manual handle crank through the operation mechanism. In a load tap changer abnormality monitoring device that monitors an operation state of a load tap changer and detects an abnormality, a drive signal detection unit that detects a drive signal when the electric motor is driven, and the operating mechanism operates. Operating signal detecting means for detecting an operating signal when the handle crank is inserted; inserting signal detecting means for detecting an inserting signal when the handle crank is inserted; and driving by the electric motor when detecting the drive signal and the operating signal. Storage means for storing the electric motor drive as, and for storing the manual drive as being manually driven when the operation signal and the insertion signal are detected; and And an arithmetic processing means for performing a process of ignoring the abnormality diagnosis of the on-load tap changer only once when the motor drive is detected next to the manual drive stored in the means. Diagnosis device for time tap changer. 3. An on-load tap in which a switching switch and a tap selector are operated by an electric motor via an operating mechanism or a manual handle crank is operated via the operating mechanism to perform a tap switching operation. An abnormality monitoring device for a tap changer under load that monitors an operation state of a switch and detects an abnormality, wherein a drive signal detection unit that detects a drive signal when the electric motor is driven, and an activation signal when the operation mechanism is activated Signal detection means for detecting the drive signal, an insertion signal detection means for detecting an insertion signal when the handle crank is inserted, and a motor drive as being driven by the motor when the drive signal and the operation signal are detected. Storage means for storing the manual drive as being manually driven when only the insertion signal is detected; and Arithmetic processing means for performing a process of ignoring the abnormality diagnosis of the on-load tap changer only once when the motor drive is detected after the manual drive, and an abnormality of the on-load tap changer. Diagnostic device. 4. The abnormality monitoring device for a load tap changer according to claim 1, wherein the drive signal detection means is a current detector for detecting a current of the electric motor. 5. The load-time detecting device according to claim 1, wherein the drive signal detecting means detects an operation of a power supply switch which operates when supplying electric power to the electric motor. Abnormality monitoring device for tap changers. 6. The abnormality monitoring device for a load tap changer under load according to claim 1, wherein the drive signal detection means detects a tap change signal instructing a start of the tap change. . 7. The on-load tap changer according to claim 1, wherein the operation signal detecting means is a torque detector for detecting a torque of a drive shaft of the operating mechanism. Monitoring device. 8. The on-load tap changer according to claim 1, wherein the operation signal detecting means is a tap position signal generating means for detecting a change in the tap position. apparatus.