JP7664866B2 - Electric operating device, electric operating mechanism, failure determination method - Google Patents

Description

Embodiments of the present invention relate to an electric operating device, an electric operating mechanism, and a fault determination method for operating an on-load tap changer used in a static induction electric appliance such as a transformer.

In a static induction device such as a transformer, the output voltage can be changed by changing the turns ratio of the coil. By providing taps with multiple turns ratios on the coil, it becomes possible to output multiple voltages. An on-load tap changer (LTC) is known as a means of switching the turns ratio of the coil in a static induction device without interrupting the voltage load. An on-load tap changer is provided inside the housing of the static induction device, and can change the output voltage of the static induction device while supplying voltage to the load.

The on-load tap changer is equipped with an electric operating mechanism that switches between multiple taps provided on the coil of the stationary induction electric machine. The electric operating mechanism generates a driving force for operating the tap changing mechanism of the on-load tap changer. Here, the driving force for operating the tap changing mechanism is, for example, the driving torque of a motor. The electric operating mechanism supplies the driving force to the on-load tap changer based on an external tap changing command, and the on-load tap changer performs the switching operation of the taps in the stationary induction electric machine.

On-load tap changers change taps in stationary induction equipment without interrupting the voltage load, so if a malfunction occurs that prevents normal operation during tap changing, it is necessary to quickly restore the system. To restore a malfunction of an on-load tap changer, it is necessary to identify whether the cause is in the drive system, electrical components, or control components.

Conventionally, to identify the cause of a malfunction in an on-load tap changer, a current clamp was attached to the cable of the motor that generates the driving force in the electric operation mechanism, and the motor overcurrent or motor phase loss due to a single-phase current loss was determined based on the current value detected by the current clamp. However, such a determination based on the motor's driving current was not able to isolate the faulty part in the on-load tap changer or the electric operation mechanism, and the faulty part had to be identified by manual judgment.

Patent No. 6310905 Patent Publication 2006-128237

As such, conventional electric operating devices, electric operating mechanisms, and failure determination methods have the problem that they require dedicated equipment and manual judgment is required to identify the faulty part and to detect failures at the stage of minor failures that lead to serious failures. The problem that the present invention aims to solve is to provide an electric operating device, electric operating mechanism, and failure determination method that can eliminate the need for manual judgment without providing dedicated equipment.

According to an embodiment, the electric operating device controls an electric operating mechanism having a motor that drives an on-load tap changer that can switch a tap provided in a stationary induction electric appliance. This electric operating device has a calculation unit that acquires the rotational position of the motor in the rotational direction and calculates the number of rotations and the rotational speed of the motor, and a determination unit that determines an abnormal mode that indicates an abnormality in the on-load tap changer and the electric operating mechanism based on the calculated amount of change in the number of rotations and the rotational speed of the motor.

According to an embodiment, the electric operation mechanism controls an on-load tap changer that can switch a tap provided in a stationary induction electric appliance. The electric operation mechanism includes a motor that drives the on-load tap changer, an angle sensor that is connected to the motor and detects the rotational position of the motor in the rotational direction, a calculation unit that obtains the rotational position of the motor in the rotational direction detected by the angle sensor and calculates the number of rotations and the rotational speed of the motor, and a determination unit that determines an abnormal mode that indicates an abnormality in the on-load tap changer and the electric operation mechanism based on the calculated amount of change in the number of rotations and the rotational speed of the motor.

Furthermore, according to an embodiment, the fault determination method determines a fault in an on-load tap changer and an electric operation mechanism having a motor that drives an on-load tap changer capable of switching a tap provided in a stationary induction electric appliance and an angle sensor that detects the rotational position of the motor in the rotational direction. This fault determination method is characterized in that it obtains the rotational position of the motor in the rotational direction from the angle sensor, calculates the number of rotations and the rotational speed of the motor based on the obtained rotational position, and determines the content of an abnormality in the on-load tap changer and the electric operation mechanism based on the amount of change in the calculated number of rotations and the rotational speed of the motor.

FIG. 2 is a block diagram showing a configuration of an electric operation mechanism according to the embodiment. 4 is a block diagram showing an outline of a judgment table in the electric operation mechanism of the embodiment. FIG. 10 is a diagram showing an example of speed profile pattern information in the electric operation mechanism of the embodiment. FIG. 11A and 11B are diagrams illustrating an example of actual measurement data of speed profile pattern information in the electric operation mechanism of the embodiment. 5 is a flowchart showing a failure determination operation in the electric operation mechanism of the embodiment.

In this embodiment, speed profile pattern information is generated from rotational position information and time information obtained from the output of an angle sensor attached to the motor of the electric operation mechanism. As samples, speed profile pattern information in expected abnormal situations and speed profile pattern information in normal situations are acquired in advance, and the cause of the failure is determined by comparing these with the actually measured pattern information. In addition, by recognizing the pattern information, an abnormality mode discrimination system that can identify the type and location of the failure can be constructed, making it possible to predict the tendency of a failure in advance. This configuration eliminates the need for a dedicated device such as a conventional failure point discrimination device.

The electric operating mechanism and the method for determining an abnormality thereof according to the embodiment will be described in detail below with reference to the drawings. Here, identical or similar parts are denoted by common reference numerals, and duplicated descriptions will be omitted.

(Configuration of the Electric Operation Mechanism of the Embodiment)
As shown in FIG. 1, an electric operation mechanism 1 of the embodiment includes a motor 20, an angle sensor 30, and an electric operation device 100. The motor 20 has a rotatable electric shaft 22. The motor 20 is connected (coupled) to an on-load tap changer 10 via the electric shaft 22. The motor 20 generates a driving force by rotating the electric shaft 22. The generated driving torque is transmitted to the on-load tap changer 10 via the electric shaft 22. The on-load tap changer 10 performs tap switching of a stationary induction machine (not shown) by the driving torque of the motor 20 transmitted by the electric shaft 22. In the following description, the rotation of the electric shaft 22 of the motor 20 may be simply referred to as the rotation of the motor 20.

The angle sensor 30 is a sensor that outputs the mechanical displacement of the rotation of the motor 20 as an electrical signal. The angle sensor 30 can be realized by, for example, an encoder, but is not limited to this as long as it can detect the rotation angle. The angle sensor 30 outputs, for example, the rotation displacement or the rotation angle as a pulse signal. The mechanical displacement of the rotation can be expressed as a relative position (rotational position) regarding the rotation. That is, the angle sensor 30 can detect the relative position in the circumferential direction of the vertical cross section in the axial direction of the electric shaft 22 as the rotational position of the electric shaft 22. The angle sensor 30 is, for example, connected to the electric shaft 22 coaxially or via a gear to the electric shaft 22, but is not limited to this. The angle sensor 30 does not need to be directly connected to the electric shaft 22 as long as the rotation is synchronized with the electric shaft 22. Based on the rotational position of the electric shaft 22 detected by the angle sensor 30, it is possible to calculate the number of rotations and the rotational speed of the electric shaft 22. In the following description, the "rotational position" includes the "rotational angle". Here, the rotation speed is calculated as the number of rotations per unit time, or the change in the number of rotations over time (differential value with respect to time).

The electric operating device 100 has the function of controlling the motor 20 and judging faults that occur inside and outside the electric operating mechanism 1. The electric operating device 100 provides start and stop signals to the motor 20 and receives the detection results of the angle sensor 30. The electric operating device 100 has a control panel 110, an instruction processing unit 120, a memory unit 130, a counter 140, a motor control unit 150, an angle sensor processing unit 160, and a profile determination unit 170.

The control panel 110 is an interface that receives a tap change command for the electric operating device 100. The tap change command may be input by a switch or the like provided on the control panel 110, or may be input as a signal from a higher-level device.

The instruction processing unit 120 is a calculation block that processes the tap change command received by the control panel 110. The instruction processing unit 120 calculates the number of rotations of the motor 20 required by the on-load tap changer in response to the tap change command, and issues a motor control command to the motor control unit 150. The number of rotations of the motor 20 corresponding to the tap change command may be specified in advance in the form of a correspondence table, and may be selected from there.

The memory unit 130 stores the number of rotations of the motor 20 required in response to the tap change command referenced by the instruction processing unit 120 as motor control information. In addition, the memory unit 130 stores judgment information used by the electric operating device 100 to perform fault detection and fault judgment in the on-load tap changer 10 and the electric operating mechanism 1. Examples of judgment information used to perform fault judgment include monitoring information, a judgment table that associates corresponding abnormality modes, malfunction events, and fault contents/faulty parts, and speed profile pattern information that records the relationship between the number of rotations and the rotation speed of the motor 20 obtained in advance by operating the on-load tap changer 10 and the electric operating mechanism 1.

The counter 140 is an arithmetic block that counts time based on an external trigger. The counter 140 generates the count and timing signals required to calculate the number of rotations and rotation speed of the angle sensor 30.

The motor control unit 150 is a circuit block that generates a start signal and a stop signal that control the supply of drive power to the motor 20. The motor control unit 150 generates a start signal and a stop signal for the motor 20 based on the motor control command sent from the instruction processing unit 120, and outputs them to the control unit of a power supply switching device such as an electromagnetic contactor (not shown). The start signal is a signal that commands the motor 20 to supply power from the drive power source, and the stop signal is a signal that commands the motor 20 to stop supplying the drive power to the motor 20. The motor control unit 150 is configured to receive the number of rotations of the motor 20 from the angle sensor processing unit 160, and after generating the start signal, generates and outputs a stop signal when the number of rotations of the motor 20 reaches the number of rotations specified in the motor control command. The calculated (or specified) number of rotations may be set as a target value, and the output signal of the angle sensor 30 after the motor is started may be used as a feedback signal to control the rotation angle.

The angle sensor processing unit 160 is a calculation block that calculates the number of rotations and the rotation speed of the motor 20 based on the electrical signal indicating the rotation position of the motor 20 sent from the angle sensor 30. In detail, the angle sensor processing unit 160 performs a calculation to convert the rotation position signal from the angle sensor 30 into one rotation for every rotation angle of 2π (360 degrees) and calculates the integrated value. The angle sensor processing unit 160 also calculates the rotation speed by performing a differential calculation of the rotation position signal from the angle sensor 30. The number of rotations of the motor 20 calculated by the angle sensor processing unit 160 is used as a criterion for the motor control unit 150 to stop the motor 20. The number of rotations and the rotation speed of the motor 20 calculated by the angle sensor processing unit 160 are used as basic data for the profile determination unit 170 to determine the fault location and fault type of the on-load tap changer 10 and the electric operating device 1.

The profile determination unit 170 is a calculation block that determines the location and nature of a fault in the on-load tap changer 10 or the electric operation mechanism 1 based on the number of rotations and the rotation speed of the motor 20 calculated by the angle sensor processing unit 160 and the speed profile pattern information stored in the memory unit 130. In addition, the profile determination unit 170 also performs calculations such as updating the speed profile pattern information and future predictions.

(Judgment table and speed profile pattern information)
The electric operation mechanism 1 of the embodiment shown in Fig. 1 uses the number of rotations and the rotation speed of the motor shaft 22 of the motor 20 that drives the on-load tap changer 10 to determine the location and nature of a fault in the on-load tap changer 10 or the electric operation mechanism 1. The determination of the location and nature of the fault is performed based on a determination table exemplified in Fig. 2. The determination table is stored in advance in the storage unit 130.

The judgment table associates each element of "monitoring information," "abnormal mode," "malfunction event," and "fault content/location." As shown in FIG. 2, when the profile judgment unit 170 acquires the number of rotations and the rotation speed of the electric shaft 22 of the motor 20 from the angle sensor processing unit 160 as monitoring information, the abnormal state (abnormal mode) and the malfunction event are selected based on the value and the change over time. When the malfunction event is specified, the candidates of the fault location and the fault content are narrowed down. Examples of the abnormal mode include "speed reduction," "unresponsive," "intermediate stop 1," "intermediate stop 2," and "runaway." The threshold value and the reference time that are the basis for the profile judgment unit 170 to judge the abnormal mode are set taking into consideration the characteristics of the pattern of each abnormal mode. In other words, the threshold value and the time can be set as the reference with a certain degree of width.

"Speed drop" is an event in which the rotational speed of the motor 20 does not reach a predetermined rotational speed after starting is complete. Since a certain load torque is applied to the motor 20, causing a speed drop due to an increase in load, it is determined to be a failure of a mechanical part in the drive system of the motor 20 (a in Figure 2). In this case, examples of failures include sticking of the mechanism of the on-load tap changer 10, sticking of the handle mechanism, sticking of the limit mechanism, and sticking of the bevel gear for the electric shaft.

"No response" is an event in which the on-load tap changer 10 does not respond to a switching command, and is presumed to be caused by an electrical failure that causes the motor 20 to not rotate at all (b) or a mechanical failure that causes the motor 20 to rotate only a little and then stop (c). If the motor 20 does not rotate at all, this is considered to be a malfunction in the circuit, so it is determined that there is a malfunction in the electrical components for the motor circuit and control. For example, electrical malfunctions include a disconnection of the motor connection line, a malfunction of the relay for operating the electromagnetic switch, a malfunction of the electromagnetic switch, an abnormality in the MCCB, and a malfunction due to a ground fault or insulation breakdown in the power line of the motor 20. If the motor 20 rotates only a little, this is considered to be a malfunction in the mechanical components, so it is determined that there is a malfunction in the mechanical components of the on-load tap changer 10 or the motor 20. For example, mechanical malfunctions include a malfunction due to a stuck mechanism of the on-load tap changer 10, a stuck handle mechanism, a stuck limit mechanism, or a stuck bevel gear for the electric shaft.

"Halt 1" is an event in which the operation of the on-load tap changer 10 is not completed and stops midway. An excessive load torque is applied to the motor 20, causing the starting current to continue to flow, and for example, the operation of a relay causes the rotation of the motor 20 to suddenly drop and stop. This is determined to be a failure of a mechanical part in the drive system of the motor 20 (d). For example, examples of mechanical failures include a failure due to a stuck mechanism of the on-load tap changer 10, a stuck handle mechanism, a stuck limit mechanism, or a stuck bevel gear for the electric shaft.

"Halt 2" is an event in which the on-load tap changer 10 does not complete its operation and stops midway. Since no drive torque is applied to the motor 20 and the rotation gradually drops and stops, it is determined to be a failure in the motor circuit and control electrical components (see e in the same paragraph). In this case, examples include a break in the motor connection line, a failure in the relay for operating the electromagnetic switch, a failure in the electromagnetic switch, and a failure due to an abnormality in the MCCB.

"Runaway" is an event in which the rotation of the motor shaft 22 of the motor 20 does not stop at the specified timing. Since it occurs when power continues to be supplied to the motor 20 and the motor 20 does not stop, it is determined to be a failure in the electrical component that supplies power to the motor circuit (ibid. f). In this case, examples include a failure of the relay that operates the electromagnetic switch or a failure of the electromagnetic switch itself.

As basic information for determining the abnormal mode of the judgment table, the electric operation mechanism 1 uses speed profile pattern information that records the relationship between the number of rotations and the rotation speed of the motor 20 that drives the on-load tap changer 10. Figure 3 is an example of the speed profile pattern information.

As shown in Figure 3, the speed profile pattern information describes the changes in the number of rotations and rotation speed of the motor 20 from when the on-load tap changer 10 and the electric operation mechanism 1 start to when they stop operating. The horizontal axis of Figure 3 represents the integrated value of the number of rotations since the motor 20 is started, and the vertical axis represents the rotation speed of the motor 20. In Figure 3, the speed profile pattern information includes a profile during normal operation ("normal" in Figure 3) and profiles during abnormal operation ("a" to "f" in Figure 3).

In the profile shown by "a" in FIG. 3, the number of rotations of the motor 20 is the same as in normal operation, but the rotation speed during steady rotation remains lower than the normal rotation speed. This is a profile corresponding to the abnormal mode "speed reduction". Similarly, in the profile shown by "b", the number of rotations and the rotation speed of the motor 20 do not increase at all, and the motor 20 does not rotate. This is a profile corresponding to the abnormal mode "no response", and the malfunction event in the judgment table shown in FIG. 2 is "b) the motor does not rotate at all". Similarly, in the profile shown by "c", the number of rotations and the rotation speed of the motor 20 only increase to a significantly low value and the rotation stops. This is a profile corresponding to the abnormal mode "no response", and the malfunction event in the judgment table shown in FIG. 2 is "c) the motor rotates only slightly".

In the profile shown by "d" in Figure 3, the rotation speed of the motor 20 drops suddenly and the rotation stops before the rotation count reaches a normal value (33 times in the example shown in Figure 3). This is a profile corresponding to abnormal mode "intermediate stop 1". Similarly, in the profile shown by "e", the rotation speed of the motor 20 drops gently and the rotation stops before the rotation count reaches a normal value. This is a profile corresponding to abnormal mode "intermediate stop 2". Similarly, in the profile shown by "f", the rotation speed of the motor 20 reaches a normal value, but the rotation count exceeds the normal value. This is a profile corresponding to abnormal mode "runaway".

In this way, the profile determination unit 170 can determine the abnormal mode of the on-load tap changer 10 and the electric operation mechanism 1 based on the number of rotations and rotation speed of the motor 20 acquired from the angle sensor processing unit 160 and the determination table and speed profile pattern information stored in the memory unit 3. In addition, by using the determination table and speed profile pattern information, it is possible to present the fault location and the candidate fault content. In the electric operation mechanism 1 of the embodiment, the determination table and the speed profile pattern information are stored in the memory unit 130, and the amount of change in the rotation and rotation speed of the electric shaft 22 that occurs during the operation of the on-load tap changer 10 is compared with the determination table and the speed profile pattern information to determine the fault location and the fault content.

Figure 4 shows an example of a speed profile obtained by measuring the rotation and rotation speed of the electric shaft 22 while the on-load tap changer 10 is in operation. As shown in Figure 4, in normal operation of the electric operating mechanism 1, the electric shaft 22 reaches a predetermined rotation speed within two rotations, and the rotation speed becomes zero when the electric shaft 22 has rotated a predetermined number of times (34 times in the example of Figure 4).

On the other hand, when the abnormal mode of the electric operation mechanism 1 is runaway, the rotation speed of the electric shaft 22 becomes zero after the rotation exceeds a predetermined number of rotations. When the abnormal mode of the electric operation mechanism 1 is speed reduction, the rotation speed of the electric shaft 22 does not reach the rotation speed during normal operation. When the abnormal mode of the electric operation mechanism 1 is unresponsive, the rotation of the electric shaft 22 is zero or stops after a few rotations. When the abnormal mode of the electric operation mechanism 1 is stop 1 or stop 2, the rotation speed of the electric shaft 22 drops sharply (stop 1) or drops gradually (stop 2) before the rotation of the electric shaft 22 reaches a predetermined number of rotations.

The speed profile pattern information is stored in advance in the memory unit 130, but may be updated based on the number of rotations and rotation speed actually measured while the electric operating mechanism 1 is in operation.

(Operation of the Electric Operation Mechanism of the Embodiment)
The operation of the electric operation mechanism 1 of the embodiment will be described below with reference to Fig. 1 and Fig. 5. A judgment table and speed profile pattern information are stored in advance in the storage unit 130. The control panel 110 receives a switching command from a user (S200). The switching command may be sent by a signal from a higher-level device.

When the switching command is received, the instruction processing unit 120 calculates the number of rotations of the motor 20 required by the on-load tap changer 10 according to the content of the switching command. Corresponding information may be stored in advance in the storage unit 130, and the instruction processing unit 120 may select the number of rotations by referring to the corresponding information. The instruction processing unit 120 sends a motor control command including the calculated number of rotations to the motor control unit 150. The motor control unit 150 generates a start signal and a stop signal for the motor 20 based on the motor control command to control the motor 20 (S210). When the motor 20 receives a supply of driving power based on the start signal, the motor 20 rotates the electric shaft 22 to supply driving torque to the on-load tap changer 10.

When the motor control unit 150 generates a start signal for the motor 20, the counter 140 starts counting the drive control time (S220). This count is used for timeouts in the event of a malfunction.

The angle sensor 30 outputs an electrical signal (pulse signal) corresponding to the rotational position of the electric shaft 22 in response to the rotation of the electric shaft 22. The angle sensor processing unit 160 receives the electrical signal output by the angle sensor 30, and calculates the number of rotations and the rotation speed of the electric shaft 22 after the motor control unit 150 generates the start signal (S230).

The profile determination unit 170 records the number of rotations and the rotation speed of the electric shaft 22 calculated by the angle sensor processing unit 160 in the memory unit 130 and generates actually measured speed profile pattern information (S240).

The profile determination unit 170 compares the measured speed profile pattern information with the speed profile pattern information stored in the storage unit 130 and prepared in advance (S250). The parameters to be compared are determined based on the determination table stored in the storage unit 130. For example, the comparison may be made on the number of rotations of the electric shaft 22 corresponding to the abnormal mode "unresponsive", the rotation speed of the electric shaft 22 corresponding to "speed reduction", the reduction in the rotation speed of the electric shaft 22 corresponding to "intermediate stop 1" and "intermediate stop 2", and the number of rotations of the electric shaft 22 corresponding to "runaway". The comparison of the speed profile pattern information may be made by comparing parameters with each other, or by comparing profile patterns as image data with each other.

If there is no rotation position information (No in S250), i.e., if the profile determination unit 170 cannot obtain the number of rotations or the rotation speed from the angle sensor processing unit 160, the profile determination unit 170 refers to the count value of the counter 140 and determines whether or not a timeout has occurred (S260). If the timeout has not been reached (No in S260), the profile determination unit 170 continues to receive the number of rotations and the rotation speed and to generate the speed profile pattern information (S240). If the timeout has been reached (Yes in S260), the profile determination unit 170 determines that the abnormal mode is "unresponsive" (S270).

If there is information on the rotational position (Yes in S250), the profile determination unit 170 monitors whether the rotational speed becomes zero after increasing (S280). If the rotational speed becomes zero and the rotation of the electric shaft 22 stops (Yes in S280), the stop occurs within a reference time (Yes in S290), and the number of rotations required for deceleration is within a predetermined threshold (Yes in S300), the profile determination unit 170 determines that the abnormal mode is "Halt 1" in which the rotational speed drops suddenly (S310). On the other hand, if the number of rotations required for deceleration exceeds a predetermined threshold (No in S300), the profile determination unit 170 determines that the abnormal mode is "Halt 2" in which the rotational speed drops gradually (S320). Here, the reference time on which the profile determination unit 170 makes a judgment may be specified with a certain degree of width.

If the rotation speed does not become zero and the rotation of the electric shaft 22 does not stop, the motor control unit 150 generates a stop signal and stops the supply of drive power to the motor 20 when the actual number of rotations of the motor 20 received from the angle sensor 30 reaches the number of rotations of the motor 20 specified in the motor control command (S330).

When the motor 20 stops based on a motor control command (S330), or when the rotation speed becomes zero and the rotation of the electric shaft 22 stops (Yes in S280) and the stop exceeds a reference time (No in S290), the profile determination unit 170 determines whether the rotation position of the electric shaft 22 has exceeded a predetermined position, i.e., whether the rotation of the electric shaft 22 has exceeded a predetermined number of rotations (S340). When the rotation of the electric shaft 22 has exceeded the predetermined number of rotations (Yes in S340), the profile determination unit 170 determines that the abnormal mode is "runaway" (S350).

If the rotation of the electric shaft 22 does not exceed the predetermined number of rotations (No in S340), the profile determination unit 170 stops the counting operation of the counter 140 and determines whether the steady-state value of the rotation speed of the electric shaft 22 is within a predetermined threshold value (S370). If the steady-state value of the rotation speed is equal to or less than the threshold value (Yes in S370), the profile determination unit 170 determines that the abnormal mode is a "speed drop" that does not reach the specified speed (S390).

If the steady-state value of the rotation speed exceeds the predetermined threshold value (No in S370), the profile determination unit 170 determines that the on-load tap changer 10 has been switched normally (S380). The result of the determination is provided to the user via the control panel 110 and is recorded in the memory unit 130.

When the profile determination unit 170 determines an abnormal mode (S270, S310, S320, S350, S360), the profile determination unit 170 provides the predicted fault location and fault content to the user through the control panel 110 based on the type of abnormal mode and the contents of the determination table stored in the memory unit 130, and records it in the memory unit 130 (S400).

(Correction of speed profile pattern information)
The speed profile pattern information stored in the memory unit 130 specifies basic information of the abnormal mode, but the operating load conditions may differ depending on individual differences in the equipment and the type of on-load tap changer 10. In such cases, it becomes difficult to accurately determine the abnormal mode.

Therefore, the on-load tap changer 10 and the motorized operating mechanism 1 are set in an operable state, and then the on-load tap changer 10 and the motorized operating mechanism 1 are operated multiple times. As a result, the profile determination unit 170 records the acquired number of rotations and rotation speed in the storage unit 130, and calculates the average value of the maximum rotation speed from the record and adds it to the speed profile pattern information as basic information. In the subsequent determination operation by the profile determination unit 170, the ratio to the maximum rotation speed in the normal operating state is multiplied as a parameter, making it possible to correct threshold values such as the rotation speed of the speed reduction and the number of decelerated rotations included in the speed profile pattern information. Such corrections may be performed when the on-load tap changer 10 and the motorized operating mechanism 1 are not operating, or may be performed by the profile determination unit 170 at any time during operation.

(Reuse of speed profile pattern information)
The profile determination unit 170 periodically records the speed profile, and by combining the measured speed profile with the time series information at the time of measurement, it is possible to extrapolate and estimate the transition in the rotation speed, thereby calculating the number of years until a speed decrease occurs due to an increase in load caused by aging. The calculated result can be output via the control panel 110.

In this way, the electric operation mechanism of the embodiment enables multiple anomaly detection compared to conventional fault point determination devices, making it possible to reduce the amount of work required for fault determination. In addition, the basic configuration of the electric operation mechanism makes it possible to detect the fault mode of the on-load tap changer without adding devices such as an ammeter, torque meter, or voltmeter, thereby enabling cost and labor savings and sophistication in maintenance. Furthermore, it makes it possible to automatically determine the fault mode from a speed profile consisting of the number of rotations and rotation speed of the motor's electric shaft, making it possible to determine the cause of the fault at an earlier stage than with conventional configurations.

Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

1...electrical operation mechanism, 10...on-load tap changer, 20...motor, 22...electric shaft, 30...angle sensor, 100...electrical operation device, 110...control panel, 120...instruction processing unit, 130...storage unit, 140...counter, 150...motor control unit, 160...angle sensor processing unit, 170...profile determination unit 170.

Claims (9)

An electric operating device for controlling an electric operating mechanism having a motor that drives an on-load tap changer that can change a tap provided in a stationary induction electric appliance,
a calculation unit that acquires a rotational position of the motor in a rotational direction and calculates a number of rotations and a rotational speed of the motor;
a determination unit that determines an abnormality mode indicating an abnormality in the on-load tap changer and the electric operation mechanism based on the calculated changes in the number of rotations and the rotation speed of the motor;
An electrically operated operating device comprising: A storage unit stores profile pattern information indicating a relationship between the number of rotations and the rotation speed of the motor during operation of the on-load tap changer, and a judgment table correlating amounts of change in the number of rotations and the rotation speed of the motor during the operation in the profile pattern information with the abnormal mode in each of the on-load tap changer and the electric operation mechanism,
the determination unit determines abnormalities in the on-load tap changer and the motor operation mechanism based on the number of rotations and the rotation speed of the motor calculated by the calculation unit, and the profile pattern information and the determination table stored in the storage unit;
2. The electric operating device according to claim 1, 3. The electric operating device according to claim 2, wherein the judgment table includes information correlating the amount of rotational displacement of the motor, the value of the rotational speed of the motor and the amount of change therein with a fault location and a fault mode characterized by these. 3. The electric operating device according to claim 2, wherein the determination unit generates a speed profile pattern in which an amount of change in rotational speed for each rotation of the motor is recorded from the start of rotation of the motor to the end of rotation, and determines the abnormality mode, which indicates an abnormality in the on-load tap changer and the electric operating mechanism, by comparing the generated speed profile pattern with the profile pattern information stored in the memory unit . The electric operating device according to claim 4, characterized in that the judgment unit identifies the faulty part and the faulty mode in the on-load tap changer and the electric operating mechanism from the abnormal mode based on the judgment table. 6. The electric operating device according to claim 4 , wherein the determination unit updates the speed profile pattern using the number of rotations and the rotation speed of the motor calculated by the calculation unit. The electric operating device according to claim 4, characterized in that the determination unit stores the calculated speed profile patterns in the storage unit, compares the calculated speed profile patterns in a time series, and estimates the recommended maintenance timing. An electric operation mechanism for controlling an on-load tap changer capable of switching a tap provided in a stationary induction electric appliance,
a motor for driving the on-load tap changer;
an angle sensor coupled to the motor to detect a rotational position of the motor in a rotational direction;
a calculation unit that acquires a rotational position in a rotational direction of the motor detected by the angle sensor and calculates a number of rotations and a rotational speed of the motor;
a determination unit that determines an abnormality mode indicating an abnormality in the on-load tap changer and the electric operation mechanism based on the calculated changes in the number of rotations and the rotation speed of the motor;
An electrically operated mechanism equipped with An electric operation mechanism including a motor that drives an on-load tap changer that is capable of switching a tap provided in a stationary induction electric appliance and an angle sensor that detects a rotational position in a rotational direction of the motor, and a method for determining a fault in the on-load tap changer, comprising:
acquiring a rotational position of the motor in a rotational direction from the angle sensor;
Calculating the number of rotations and the rotation speed of the motor based on the acquired rotation position;
A fault determination method characterized by determining the type of abnormality in the on-load tap changer and the motor-operated operating mechanism based on the calculated changes in the number of rotations and the rotation speed of the motor.

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