JP2008293682A - Operation characteristic monitoring device of switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an operation characteristics monitoring device of a switch with high precision by directly detecting an operation start-up time and an operation completion time of the switch without using status change of an auxiliary contact. <P>SOLUTION: A stroke sensor 18 to detect displacement of a moving member 15 into the main contact inserting direction, and displacement in the main contact tripping direction is installed. A measuring part 2a detects a time from a supply starting time of an excitation current into coils (10, 11) for operation detected from output of current transformers 30, 31 to a detection starting time of the displacement of the stroke sensor 18 as a first operation time, and detects a time from the detection starting time of the displacement of the stroke sensor 18 to the detection completion time as a second operation time. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an operation characteristic monitoring device for a switch, and more particularly to an operation characteristic monitoring device for a switch suitable for diagnosing an abnormality in the operation characteristics of a circuit breaker or a disconnector for opening and closing a main circuit of a power facility. .

  In monitoring the operating characteristics of the switch for opening and closing the main circuit of the power equipment, the excitation current flowing through the closing coil or tripping coil in response to the generation of a command for instructing the switching operation of the switch, and the position of the movable contact Based on the auxiliary contact signal indicating, the time from when the command is generated until the switch starts operating (first time) and the time until the operation is completed thereafter (second time) are monitored. Thus, a method of determining the quality of the operating characteristics of the switch is adopted.

  As a method for detecting the operation time of the switch, conventionally, the start time and end time of the operation are obtained by the closing / opening switching timing which is a change in the state of the auxiliary contact (for example, Patent Document 1).

JP 2003-308751 A

  However, in the method of detecting the operation time of the switch disclosed in Patent Document 1 above, the operation time of the auxiliary contact has a large variation of, for example, ± 5 ms, so that the operation time of the switch is accurately detected. There is a problem that you can not.

  In addition, although the operating pressure for shifting from one of the open state and the closed state of the switch to the other state is also a parameter that affects the operation time, the operation characteristic monitoring of the switch disclosed in the above-mentioned Patent Document 1 is performed. In the method, since the operation pressure is not taken into consideration, there is a problem that the method cannot be applied to the operation characteristic monitoring of a switch whose operation system is pneumatic or hydraulic.

  The present invention has been made in view of the above, and it is possible to directly detect the operation start time and the operation end time of the switch without using a change in the state of the auxiliary contact, so that the operation of the switch with high accuracy can be detected. The object is to obtain a characteristic monitoring device.

  Further, according to the present invention, in the above invention, by including the operation pressure in the parameter affecting the operation time, the operation time of the switch of the pneumatic operation system or the switch of the hydraulic operation system can be accurately monitored. The object is to obtain an operating characteristic monitoring device.

  Another object of the present invention is to provide an operating characteristic monitoring device for a switch that enables more reliable monitoring of operating characteristics in the above invention.

  In order to achieve the above-described object, the present invention provides a first operation time from the input of an operation start command to the switch to the start of operation of the switch, and a second operation from the start of operation of the switch to the end of operation. An operating time detecting unit for detecting the operating time, a parameter detecting unit for detecting a value of a parameter affecting each of the first operating time and the second operating time of the switch, and the parameter detecting unit An operation time correction unit that corrects a detection time of the operation time detection unit according to a difference between a detection value and a reference value of the parameter, and a settling value that is a reference value for the operation time of the switch and the operation time correction unit. And a determination unit that determines whether or not the operation time of the switch is abnormal by comparing with the measured operation time, wherein the operation time detection unit is configured such that the switch is in an open state and a closed state. A stroke sensor for detecting displacement in the process of transitioning from one state to the other state, and the time from the start of supplying the excitation current to the operating coil to the start of detecting the displacement of the stroke sensor is The first operation time is detected, and the time from the start of detection of the displacement of the stroke detection means to the end of detection is detected as the second operation time.

  According to the present invention, since the detection start time and the detection end time of the stroke sensor that directly detects the operation process of the switch can be detected as the operation start time and the operation end time of the switch, the switch can be accurately detected. The operation start time and the operation end time can be detected, and the operation time can be accurately monitored.

  Exemplary embodiments of a switch operating characteristic monitoring apparatus according to the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG.
1 is a block diagram showing a configuration of a switch operating characteristic monitoring apparatus according to Embodiment 1 of the present invention. In the first embodiment, in order to facilitate understanding, an application example to the conventional example (Patent Document 1) will be described.

  In FIG. 1, the operation characteristic monitoring device for a switch is determined as a measurement unit 2a and a diagnosis unit 3a as a configuration for determining the presence / absence of an abnormality or an abnormal part during the switching operation of the circuit breaker 1 that is a switch to be monitored. Part 4a.

  The circuit breaker 1 is, for example, a circuit breaker that opens and closes a three-phase main circuit in a power facility, and a main contact (not shown) is configured using, for example, a gas circuit breaker (GCB) or a vacuum circuit breaker (VCB). ing. As shown in FIG. 1, as a control element for causing the main contact (not shown) to perform the opening / closing operation, a closing coil (C) 10, a tripping coil (T) 11, and an auxiliary b contact 12 are provided. And an auxiliary contact point 13, an operating device 14, and a mover 15, and a temperature sensor 16 that detects the ambient temperature as one element of a parameter detection unit that affects the operating time. The detection signal of the temperature sensor 16 is input to the measurement unit 2a.

  The auxiliary b-contact 12 and the auxiliary a-contact 13 perform reverse opening / closing operations in conjunction with the insertion / removal of a main contact (not shown), but the closing coil (C) 10 and the auxiliary b-contact 12 are connected in series. The trip coil (T) 11 and the auxiliary a contact 13 are connected in series.

  One end of the series circuit of the closing coil (C) 10 and the auxiliary b contact 12 is connected to one electrode end (positive electrode end) of the operation power supply 25 composed of a DC power supply via a closing command contact 20. The other end of the series circuit of the closing coil (C) 10 and the auxiliary b contact 12 is connected to the other electrode end (negative electrode end) of the operating power supply 25, and a current transformer 30 is provided in the connection line. ing.

  One end of the series circuit of the trip coil (T) 11 and the auxiliary a contact 13 is connected to one electrode end (positive electrode end) of the operation power supply 25 via a closing instruction contact 21. The other end of the series circuit of the trip coil (T) 11 and the auxiliary a contact 13 is connected to the other electrode end (negative electrode end) of the operation power supply 25, and a current transformer 31 is provided in the connection line. It has been.

  Each of the current transformers 30 and 31 includes a shunt resistor, and detects and converts the voltage of the exciting current that flows to the measurement unit 2a. The positive end of the operating power supply 25 is connected to the measuring unit 2a.

  In the first embodiment, in such a conventional example, in order to increase the measurement accuracy of the operation time, the circuit breaker 1 operates as the operation pressure in the operation device 14 as one element of a parameter detection unit that affects the operation time. And a stroke sensor 18 for detecting the displacement (stroke) of the mover 15 as one element of the operation time detector. The detection signals of the operation pressure sensor 17 and the stroke sensor 18 are input to the measurement unit 2a.

  The stroke sensor 18 is a rotary encoder, a potentiometer, a laser displacement meter, or the like, but is attached with high installation reliability using a dedicated attachment jig.

  In the above configuration, the control operation of turning on the main contact (not shown) of the circuit breaker 1 is performed as follows. In an initial state where a main contact (not shown) is not turned on, the auxiliary b contact 12 is in a closed state, and the auxiliary a contact 13 is in an open state.

  When the closing command contact 20 is closed in response to a closing command from a control device (not shown), both ends of the series circuit of the closing coil (C) 10 and the auxiliary b contact 12 are connected to both electrode ends of the operation power supply 25. The Since the auxiliary b contact 12 is in a closed state, an exciting current flows through the closing coil (C) 10.

  When an exciting current flows through the closing coil (C) 10, the operating device 14 drives and displaces the mover 15 in the closing direction of the main contact (not shown), so that the main contact is turned on. When the main contact is turned on, the auxiliary b contact 12 is opened, so that the making coil (C) 10 is in a non-excited state, and the operating device 14 stops driving the mover 15. The mover 15 maintains the state where the main contact is turned on. At this time, when the auxiliary b contact 12 is opened, the auxiliary a contact 13 is closed.

  That is, an exciting current flows through the closing coil (C) 10 during a period from when the closing command contact 20 is closed until the auxiliary b contact 12 is opened. The excitation current within that period is detected by the current transformer 30 and input to the measuring unit 2a. The measurement unit 2a detects the output change start time of the current transformer 30 as the input timing of the input command.

  Then, the operating pressure generated by the operating device 14 during the period in which the exciting current flows through the closing coil (C) 10 is detected by the operating pressure sensor 17 and input to the measuring unit 2a. Further, the displacement (stroke) of the mover 15 driven by the operating device 14 is detected by the stroke sensor 18 and input to the measuring unit 2a.

  Here, in the first embodiment, the time point when the mover 15 starts to be displaced in the direction in which the main contact is turned on is the time point when the signal output of the stroke sensor 18 starts changing. This is detected as the start-up operation start timing of the device 1. In addition, since the point in time when the mover 15 stops the displacement of the main contact in the closing direction is the time point when the change in the signal output of the stroke sensor 18 ends, the measuring unit 2a uses this as the closing operation end timing of the circuit breaker 1. To detect.

  Next, a control operation for releasing a main contact (not shown) of the circuit breaker 1 is performed as follows. When the opening command contact 21 is closed in response to a trip command from a control device (not shown), both ends of the series circuit of the trip coil (T) 11 and the auxiliary a contact 13 are connected to both electrode ends of the operation power supply 25. Connected. Since the auxiliary a contact 13 is in a closed state as described above, an exciting current flows through the trip coil (T) 11.

  When an excitation current flows through the tripping coil (T) 11, the operating device 14 drives and displaces the mover 15 in the direction of tripping the main contact (not shown), so that the main contact is pulled off. When the main contact is removed, the auxiliary a contact 13 is opened, the trip coil (T) 11 is de-energized, and the operating device 14 stops driving the mover 15. The mover 15 maintains the state where the main contact is removed. At this time, when the auxiliary a contact 13 is opened, the auxiliary b contact 12 is closed.

  That is, an excitation current flows through the tripping coil (T) 11 during the period from when the opening command contact 21 is closed until the auxiliary a contact 13 is opened. The excitation current within that period is detected by the current transformer 31 and input to the measurement unit 2a. The measurement unit 2a detects the output change start time of the current transformer 31 as the trip command input timing.

  Then, the operating pressure generated by the operating device 14 during the period in which the exciting current flows through the tripping coil (T) 11 is detected by the operating pressure sensor 17 and input to the measuring unit 2a. Further, the displacement (stroke) of the mover 15 driven by the operating device 14 is detected by the stroke sensor 18 and input to the measuring unit 2a.

  Here, in the first embodiment, the time when the mover 15 starts to be displaced in the direction of tripping the main contact is the time when the change in the signal output of the stroke sensor 18 starts. This is detected as the trip operation start timing of the circuit breaker 1. In addition, since the point in time when the mover 15 stops moving in the direction of tripping the main contact is the time point when the change in the signal output of the stroke sensor 18 ends, the measuring unit 2a ends the tripping operation of the circuit breaker 1. Detect as timing.

  FIG. 2 is a characteristic diagram for explaining the operation time measured by the measurement unit shown in FIG. FIG. 2 shows the relationship between the excitation coil excitation period and stroke characteristics when the circuit breaker 1 can be normally turned on. In FIG. 2, a characteristic 35 indicates a waveform of an excitation current flowing in the closing coil (C) 10 detected by the current transformer 30. A characteristic 36 indicates a stroke characteristic of the mover 15 detected by the stroke sensor 18.

  The exciting current characteristic 35 indicates the following. When the circuit breaker 1 can be normally turned on, an exciting current flows out to the closing coil (C) 10 at a timing 41 when the closing instruction contact 20 is closed in response to the closing instruction. The exciting current increases almost linearly. However, when it reaches a certain magnitude, the operation device 14 starts to move, so that it decreases due to the influence of the load fluctuation and reaches the inflection point 42 and then increases again. It shifts to a substantially constant value, and the auxiliary b contact 12 opens in the process, so that it suddenly descends and disappears.

  The stroke characteristic characteristic 36 indicates the following. The controller 14 starts driving the mover 15 at a timing 43 when the excitation current changes from the inflection point 42 to a substantially constant value. This timing 43 is the change start time of the signal output of the stroke sensor 18 described above, and is the start operation start timing of the circuit breaker 1. Since the operating device 14 displaces the mover 15 in the direction in which the main contact is made by the operating pressure, the signal output of the stroke sensor 18 increases almost linearly. Then, at the timing 44 when the closing coil (C) 10 is in a non-excited state and the operation unit 14 stops displacing the mover 15 in the closing direction of the main contact, the signal output of the stroke sensor 18 is constant from an increasing tendency. Move to value output. This timing 44 is the end point of the change in the signal output of the stroke sensor 18 described above, and the closing operation end timing of the circuit breaker 1.

  In the first embodiment, when the main contact is turned on, the measuring unit 2a has a closing operation start timing 43 of the circuit breaker 1 indicated by the signal output of the stroke sensor 18 from the rising timing 41 of the excitation current detected by the current transformer 30. Is measured as the first operation time T1, and the operation time from the closing operation start timing 43 of the circuit breaker 1 to the closing operation end timing 44 indicated by the signal output of the stroke sensor 18 is defined as the second operating time T2. Each is measured and given to the diagnosis unit 3a.

  The same applies to the tripping of the circuit breaker 1, and the measuring unit 2a performs the tripping operation of the circuit breaker 1 indicated by the signal output of the stroke sensor 18 from the rise timing (41) of the excitation current detected by the current transformer 31. The first operation time T1 until the start timing (43) and the second operation from the trip operation start timing (43) of the circuit breaker 1 to the trip operation end timing (44) indicated by the signal output of the stroke sensor 18 The time T2 is measured and given to the diagnosis unit 3a.

  FIG. 3 is a characteristic diagram showing the relationship between the operating pressure of the operating device 14 and the charging time. In FIG. 3, the horizontal axis is the operating pressure, and the vertical axis is the charging time. As shown in FIG. 3, the input time tends to be longer as the operating pressure is lower. The same applies to the tripping.

  Therefore, as parameters affecting the measurement accuracy of the first operation time T1 and the second operation time T2 measured as described above, in the conventional example, the ambient temperature, the voltage of the operating power supply (DC power supply) 25, and the operation Although the interval (the interval of the throwing operation and the interval of the tripping operation) was measured, the operating pressure of the operating device 14 affects the operating time as shown in FIG. Furthermore, the operation pressure of the operation device 14 is also measured.

  That is, the measuring unit 2a takes in the detected temperature value of the temperature sensor 16 and the detected operating pressure value of the operating pressure sensor 17 when measuring the first operating time T1 and the second operating time T2, respectively, The voltage and the operation interval of the power supply 25 are detected, respectively, and given to the diagnosis unit 3a.

  When the temperature data of the ambient temperature is obtained from another path, the temperature sensor 16 is not necessary, and the temperature data from the other path is given to the diagnosis unit 3a. Further, since there is a method of estimating the voltage of the operating power supply 25 in addition to the method of directly measuring, the estimation method may be used.

  When the detection operation time (T1, T2), the detection temperature value, the detection operation interval, the detection operation power supply voltage and the detection operation pressure value are input from the measurement unit 2a, the diagnosis unit 3a receives the detection temperature value, the detection operation interval, and the detection operation power supply. According to the difference between the voltage and the detected operation pressure value and the reference value for each, a correction value for the detected operation time (T1, T2) at each parameter value is calculated. In addition, the reference value of ambient temperature is 20 degreeC, for example. The reference value of the operation interval is, for example, 1 minute. The reference values for the operating power supply voltage and the operating pressure are rated values.

  In the operation pressure detection by the operation pressure sensor 17, the detected value temporarily decreases immediately after the operation of the circuit breaker 1. Therefore, the operation pressure used for operation time conversion uses the detection value immediately before the operation.

  Then, the diagnosis unit 3a calculates a general-purpose operation time (T1, T2) with less error factors based on the obtained correction values, and sends the calculated correction operation time (T1, T2) to the determination unit 4a. give.

  The determination unit 4a compares the set value, which is a reference value for the operation time (T1, T2), with the correction operation time (T1, T2) calculated by the diagnosis unit 3a, thereby correcting the correction operation time (T1, T2) of the circuit breaker 1. The presence or absence of abnormality in T2) is determined, and the determination result is output to the outside.

  Here, the correspondence with the claims is shown. The operating time detector is entirely associated with the current transformers 30 and 31, the stroke sensor 18, and the measuring unit 2a. The temperature detector 16, the operation pressure sensor 17, and the measuring unit 2a all correspond to the parameter detection unit. The diagnosis unit 3a corresponds to the operation time correction unit. The determination unit 4a corresponds to the determination unit. The operating coil corresponds to the closing coil (C) 10 and the tripping coil (T) 11.

  As described above, according to the first embodiment, the stroke sensor that directly detects the operation characteristic of the switch is used to detect the start point of the stroke detection as the start time of the operation of the switch. Since the end point is detected as the end of the operation of the switch, it is possible to detect the start and end of the operation of the switch with higher accuracy than the conventional example.

  In addition, the operation pressure during operation of the switch is detected using an operation pressure sensor, and converted into an operation time under a certain condition for evaluation. Therefore, a pneumatic operation system or It is possible to accurately monitor the operating time of the hydraulic operation system switch.

Embodiment 2. FIG.
FIG. 4 is a block diagram showing a configuration of a switch operating characteristic monitoring apparatus according to Embodiment 2 of the present invention. In FIG. 4, the same or similar components as those shown in FIG. 1 (Embodiment 1) are denoted by the same reference numerals. Here, the description will be focused on the portion related to the second embodiment.

  As described above, the stroke sensor 18 is mounted with high installation reliability using a dedicated mounting jig. However, since there is a secular change, the second embodiment is the first embodiment. A configuration example for confirming the soundness or installation accuracy of the stroke sensor 18 is shown in parallel with the operation characteristic monitoring described in the above.

  That is, as shown in FIG. 4, the switch operating characteristic monitoring apparatus according to the second embodiment is different from the measurement unit 2a, diagnosis unit 3a, and determination unit 4a shown in FIG. , A determination unit 4b is provided.

  Next, the operation will be described with reference to FIGS. FIG. 5 is a characteristic diagram for explaining the operation time measured by the measurement unit shown in FIG. FIG. 6 is a characteristic diagram for explaining the operation of the determination unit shown in FIG.

  As shown in FIG. 4, the measurement unit 2b measures the first operation time T1 and the second operation time T2 in the same manner as in the first embodiment, and changes from the timing 41 in the excitation current characteristic 35. The operating time T1A to the pole 42 is measured. Since the operation time T1A <the first operation time T1, the measurement unit 2b first measures the operation time T1A, and then measures the first operation time T1 and the second operation time T2. . The operating time T1A is a third operating time referred to in the claims.

  In the second embodiment, the normality of the signal output change start point 43 of the stroke sensor 18, which is the switching timing to the second operation time T2, is confirmed using the operation time T1A and the first operation time T1. I am doing so. This is a part related to the second embodiment, and the diagnosis unit 3b and the determination unit 4b perform the following operations.

  In the diagnosis unit 3b, as described above, the operation time T1A and the first operation time T1 measured by the measurement unit 2b are the operation time under a certain condition using the ambient temperature, the operation power supply voltage, the operation interval, and the operation pressure as parameters. Convert to. Assuming that these are T1Acomp and T1comp, if the signal output change start point 43 of the stroke sensor 18 is a normal position, the time difference between the operation time T1Acomp and the operation time T1comp is a constant value, and the relationship is T1comp = T1Acomp + constant.

  In FIG. 6, the vertical axis represents the time difference B (B = T1comp−T1Acomp) between the operation time T1Acomp and the operation time T1comp, and the horizontal axis represents the number of operations. The determination unit 4b calculates the difference between the operation times T1Acomp and T1comp received from the diagnosis unit 3b, T1comp−T1Acomp = B, and manages the threshold 50 for the time difference B as shown in FIG.

  If the signal output change start point 43 of the stroke sensor 18 is a normal position, the time difference B becomes a “constant value” within the range of the threshold 50, but the signal output change start point 43 is normal as the number of operations increases. When the position deviates from the position, the time difference B changes toward the outside of the range of the threshold value 50 and eventually comes out of the range of the threshold value 50.

  In a situation where the time difference B changes toward the outside of the range of the threshold value 50, there is a possibility that the detection capability of the stroke sensor 18 itself or the installation accuracy of the stroke sensor 18 has changed.

  Therefore, the determination unit 4b monitors the situation in which the time difference B changes outside the range of the threshold value 50, and detects that the difference value B goes out of the range of the threshold value 50, the stroke sensor abnormality 55 is detected. Output to the outside.

  As described above, according to the second embodiment, the detection performance of the stroke sensor 18 itself that detects the operating time of the switch or the sensor soundness due to the installation accuracy of the stroke sensor 18 can be taken into consideration. Therefore, the operation time can be monitored with higher reliability.

  As described above, the operation characteristic monitoring device for a switch according to the present invention is useful for accurately monitoring the operation characteristic of a switch using a stroke sensor.

  The switch operating characteristic monitoring apparatus according to the present invention is useful for accurately monitoring the operating time of a pneumatic operating system or hydraulic operating system switch.

  The switch operating characteristic monitoring apparatus according to the present invention is useful for enabling more reliable monitoring of operating characteristics when a stroke sensor is used.

It is a block diagram which shows the structure of the operating characteristic monitoring apparatus of the switch by Embodiment 1 of this invention. It is a characteristic view explaining the operation time which the measurement part shown in FIG. 1 measures. It is a characteristic view which shows the relationship between the operation pressure of the operating device shown in FIG. 1, and charging time. It is a block diagram which shows the structure of the operating characteristic monitoring apparatus of the switch by Embodiment 2 of this invention. It is a characteristic view explaining the operation time which the measurement part shown in FIG. 4 measures. It is a characteristic view explaining operation | movement of the determination part shown in FIG.

Explanation of symbols

1 Circuit breaker (switch)
2a, 2b Measurement unit 3a, 3b Diagnosis unit 4a, 4b Judgment unit 10 Input coil (C)
11 Tripping coil (T)
12 Auxiliary b contact 13 Auxiliary a contact 14 Actuator 15 Movable element 16 Temperature sensor 17 Operating pressure sensor 18 Stroke sensor 20 Close circuit command contact 21 Open circuit command contact 25 Operation power supply (DC power supply)
30, 31 Current transformer

Claims (3)

An operation time detection unit for detecting a first operation time from the input of an operation start command to the switch to the start of operation of the switch and a second operation time from the start of operation of the switch to the end of operation; A parameter detection unit that detects a value of a parameter that affects each of the first operation time and the second operation time of the switch; and the difference between a detection value of the parameter detection unit and a reference value of the parameter An operation time correction unit that corrects the detection time of the operation time detection unit, a set value that serves as a reference value for the operation time of the switch, and the operation time that is corrected by the operation time correction unit are compared with each other. In the operation characteristic monitoring device of a switch provided with a determination unit that determines whether or not the operation time is abnormal,
The operation time detection unit includes a stroke sensor that detects a displacement in a process in which the switch moves from one state of an open state and a closed state to the other state,
The time from the start of supplying the exciting current to the operation coil to the start of detection of the displacement of the stroke sensor is detected as the first operation time, and the detection ends from the start of detection of the displacement of the stroke detection means. An operation characteristic monitoring device for a switch, wherein time until time is detected as the second operation time.   2. The switching according to claim 1, wherein the parameter detection unit detects an operation pressure that shifts from one state of an open state and a closed state of the switch to the other state as one of the parameters. Operating characteristic monitoring device. The operating time detector is
The time from the start of supplying the exciting current to the operating coil to the inflection point indicating the occurrence of the load fluctuation occurring in the waveform of the exciting current is detected as the third operating time,
The determination unit
It is monitored whether or not a difference value between the first operation time and the third operation time corrected by the operation time correction unit is within a threshold range, and the difference value is included in the threshold range. The switch operating characteristic monitoring device according to claim 1, wherein if there is not, it is determined that the stroke detection unit is abnormal.

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