JP4721882B2 - Circuit breaker contact wear monitoring system, circuit breaker maintenance support method, and program - Google Patents

Description

  The present invention relates to a system for monitoring the degree of wear of a contact (arc contact) of a power circuit breaker and a circuit breaker maintenance support method.

Conventionally, the internal inspection of the circuit breaker by cumulative interruption current management is performed by the relational expression of breaking current−contactor wear amount described in Non-Patent Document 1 V = α · I ^β · t (where I is the breaking current, t is This was performed when a predetermined amount of wear was reached using arc time, α and β are coefficients).

  And the technique for calculating | requiring this interruption | blocking current and arc time accurately is disclosed. (For example, refer to Patent Documents 1 to 4).

By the way, the coefficient β in the above formula usually uses a value provided by the manufacturer. However,
For example, if the DC current is included in the short-circuit current when the breaker trips, the interrupt current is not defined. May occur, leading to a drop in interruption performance and energization performance and unnecessary inspection.

Furthermore, when providing a maintenance service to a customer having a circuit breaker, unnecessary inspection may cause unnecessary expenses to the customer.
Japanese Patent Laid-Open No. 05-120945 JP 55-41640 A JP 2002-343173 A JP 2003-281975 A IEEJ Technical Report Part 2 No. 290 “Reliability and Diagnosis Technology of Circuit Breakers”

  The present invention has been made in view of the above-described circumstances, and by correcting the coefficient β of the estimated cumulative wear degree of the circuit breaker contact by actual measurement, an error in the estimated cumulative wear degree due to a difference in the measurement method of the break current and the like. Circuit breaker contact wear monitoring system, which makes it possible to accurately estimate the degree of contact wear, and to effectively notify the customer who has the breaker of the maintenance time of the breaker. It is an object to provide a device maintenance support method and program.

  In order to solve the above-described problems, a circuit breaker contact wear monitoring system according to the present invention uses means for inputting electrical information of a main circuit, means for inputting a trip signal for a circuit breaker, and electrical information and a trip signal. An estimated cumulative wear degree calculating means for calculating an arc time and a breaking current and calculating an estimated cumulative wear degree of the circuit breaker, and a judging means for determining whether the estimated cumulative wear degree is equal to or greater than a predetermined value and outputting the determination result And a measured cumulative wear degree calculating means for inputting the actual wear amount information of the arc contactor of the circuit breaker, calculating a coefficient β in the measured cumulative wear degree, and correcting the coefficient β of the estimated cumulative wear degree. Features.

  When the estimated cumulative wear degree exceeds the control value, an internal inspection is performed, a coefficient β is obtained from the actually measured cumulative wear degree, and the result is fed back for calculation of the estimated cumulative wear degree thereafter.

  Here, the degree of wear includes the wear rate and information that can be converted into the wear rate, and includes, for example, the wear amount.

  Further, the present invention is characterized in that the circuit breakers are grouped based on the operation specifications and the voltage class, and the coefficient β is corrected independently for each group. By using the same β value by grouping those having the same manufacturer's β value and common operation specifications such as the opening time, the number of samples can be increased and effective β value management becomes possible.

  Preferably, in the calculation of the estimated cumulative wear degree, it is possible to select whether the breaking current is obtained as an asymmetrical breaking current or an effective value of a general waveform. By making the calculation method of the breaking current selectable and using an appropriate calculation formula according to the specifications of the circuit breaker, it is possible to monitor contact wear with high accuracy.

  Further, the circuit breaker maintenance support method according to the present invention inputs the arc time and the breaking current information sent from the breaking current grasping device installed on the customer side to the server via the communication network, and breaks the arc contactor. A circuit breaker maintenance support method for calculating the degree of wear of the circuit breaker and transmitting the calculation result to the customer terminal, wherein the server calculates an estimated cumulative degree of wear of the circuit breaker using the arc time and the breaking current, and estimates A step of determining whether or not the cumulative wear level is equal to or greater than a predetermined value and transmitting the determination result to the customer terminal, and calculating the coefficient β in the measured cumulative wear level by inputting the actual wear amount information of the arc contactor of the circuit breaker And a step of correcting the coefficient β of the estimated cumulative wear level.

  By providing a circuit breaker wear monitoring service for multiple customers, it is possible to increase the number of data and perform high-precision management, while reducing unnecessary administrative expenses due to unnecessary inspections for customers and reducing management effort. it can.

  Note that the arc time and break current information sent from the break current grasping device is sufficient if it is information that can calculate the arc time and breaker current information. Therefore, the current data may be raw data and a trip timing signal on the time axis.

  The circuit breaker maintenance support method according to the present invention further selects whether to calculate the breaking current as an asymmetrical breaking current or an effective value of a general waveform based on the circuit breaker operation specifications in the calculation of the estimated cumulative wear degree. And

  Preferably, the method includes a step of setting, from the customer terminal, a predetermined value for determining whether or not the estimated cumulative wear level is equal to or greater than a predetermined value. Flexibility can be provided by enabling customer setting within a predetermined range.

  More preferably, the method includes a step of outputting a message as to whether an internal inspection is performed by disassembly or an X-ray diagnosis is performed based on the voltage class of the circuit breaker when the estimated cumulative wear level becomes a predetermined value or more. Thereby, a cost-effective inspection can be presented to the customer.

  A program according to the present invention is a program that operates on a computer that inputs arc time and breaking current information and calculates the degree of wear of the breaker arc contactor, and uses the arc time and breaking current to break the breaker. The process of calculating the estimated cumulative wear degree of the process, the process of determining whether the estimated cumulative wear degree is equal to or greater than a predetermined value and outputting the determination result, and the actual wear amount information of the arc contactor of the circuit breaker are input. And a process of correcting the coefficient β of the estimated cumulative wear degree by calculating the coefficient β in the actually measured cumulative wear degree.

  According to the present invention, the coefficient β of the estimated cumulative wear degree is corrected based on the measured cumulative wear degree of the circuit breaker contact. It is possible to estimate a high degree of contact wear, and it is possible to accurately notify the customer who has the circuit breaker when the circuit breaker maintenance service is performed. Can reduce unnecessary expenses.

  A first embodiment of the present invention will be described. FIG. 1 is a functional block diagram of a contact wear monitoring system according to the present embodiment.

  In this figure, the contact wear monitoring system 1 is constituted by a breaking current grasping device 20 for inputting main circuit electrical information and a breaker trip signal, and a computer device 10 connected thereto via a communication line 4.

  Here, the breaking current grasping device 20 converts the signal from the transducer 22 for inputting the current information (electrical information) of the main circuit, the transducer 23 for inputting the trip signal of the breaker, and the signals from both the transducers 22 and 23 into voltage signals. An input conversion unit 21 including an impedance conversion unit 24, an AD conversion unit 26 that converts an output signal from the impedance conversion unit 24 into a digital signal, a CPU unit 27 that executes arithmetic processing using the input data, and the computer apparatus 10 It comprises an AD conversion / arithmetic unit 25 comprising a level converter 28 for communication, a clock unit 29 for adding time information to input data, a storage device 30 for storing data, and a power supply 31. .

  Further, the computer device 10 has a function of inputting current waveform information timed via the communication line 4 and calculating the cumulative wear degree of the contact.

Next, the operation of the contact wear monitoring system 1 configured as described above will be described with reference to FIG.
The current information of the main circuit 5 is taken into the transducer 22 of the constant interruption current grasping device 20 via the main circuit current transformer 6 or the auxiliary current transformer 7. This signal is digitized via the impedance conversion means 24 and the AD conversion means 26, and time information from the timepiece unit 29 is sequentially added and stored in the storage device 30. On the other hand, when a system fault occurs and a trip signal for the circuit breaker is output (S101), this signal is input via the transducer 23, input via the impedance conversion means 24 and the AD conversion means 26, and time information And is stored in the storage device 30 (S103).

  The current waveform data stored in the storage device 30 of the interruption current grasping device 20 is sent to the computer device 10 via the communication line 4 via the level converter 28. This transmission may be, for example, one-to-one serial communication such as RS-232C, or may be performed via a communication network such as a public line. Further, instead of transferring data by transmission, the storage device 30 of the breaking current grasping device 20 is made detachable from a storage medium such as a flexible disk or a CD-ROM, and is transferred via the storage medium. May be.

  In the computer apparatus 10, the following formulas (1) and (2) are selected according to the type (type) of the circuit breaker, and the breaking current is calculated (S104).

  FIG. 3 shows the relationship between the cutoff currents of the equations (1) and (2). An arc is generated when the contact of the circuit breaker is released after a predetermined time determined by the circuit breaker specifications or the like from the circuit break command, but the current values immediately after the arc generation start point (the moment of arcing) are greatly different.

  As the type of the circuit breaker, for example, the formula (1) is selected for a two-cycle circuit breaker having a short opening time, and the formula (2) is selected for a one having a relatively long opening time. When the cutoff current is obtained by equation (1), peak detection and envelope creation processing are required, and a load is applied compared to equation (2). For this reason, about a circuit breaker with a long opening time, the interruption current value can be calculated without applying a load to the load of the computer apparatus 10 by using the equation (2).

  In addition, the voltage class may be included in the selection condition, such as Expression (2) for a relatively low voltage class (for example, 110 kV or less) and Expression (1) for a relatively high voltage class.

  Further, the arc time is obtained as the time from the moment of arcing to the zero point of the breaking cycle determined by the type of breaker.

  Next, using the collected arc time, the breaking current value obtained by the equation (1) or (2), the electrode characteristic data shown in FIG. 4, and the circuit breaker specific data such as the cumulative number of interruptions shown in FIG. (S105) The estimated cumulative wear rate Bc is calculated from the equations (3) (S106). The electrode characteristic data and the circuit breaker specific data are stored in the computer device 10.

  Here, a specification value (for example, 1.6) is used as β as an initial value.

  For each operation of the circuit breaker, the average value of the arc time and the breaking current is obtained using the data during the previous operation, and the above calculation is performed.

  In each calculation, it is determined whether or not the estimated cumulative wear rate Bc exceeds a control limit value (for example, 0.9). If the control limit value is exceeded, a caution message is output to notify it (S107).

  Then, those exceeding the control limit value are disassembled (internal inspection), and the measured cumulative wear rate Bf is obtained by the following equation (4) (S108).

  Next, using this Bf, a β value is calculated by equation (5) (S109).

  This β value is replaced with the value that has been used so far, and thereafter, the estimated cumulative wear rate of other types of accident circuit breakers of the same type is calculated using this β value. The β value should be managed according to the circuit breaker type and voltage class.

  According to the present embodiment, the management limit value of the estimated cumulative wear rate is determined, the estimated cumulative wear rate is calculated for each accident interruption, the measured cumulative wear rate is obtained by disassembly for those exceeding the limit value, and β Since the value is calculated and used to calculate the estimated cumulative wear rate, the shut-off performance and current-carrying performance due to the error between the estimated cumulative wear rate and the measured cumulative wear rate compared to using the uniform specification value Can be avoided and unnecessary inspections can be performed.

  In addition, since the calculation method of the breaking current to be used can be selected depending on the type of breaker and the voltage class, more accurate management is possible.

  In addition, it may replace with the internal inspection by dismantling and may be made to perform the diagnosis by X-ray. At this time, in consideration of cost merit or the like, the internal inspection or the X-ray diagnosis may be selected for each type of breaker and voltage class.

  The current waveform information may be recorded using the breaking current grasping device shown in FIG. 1, but the same electrical information is collected and a general-purpose system failure analysis program (hereinafter referred to as waveform explorer) is used. Then, the arc time and interruption current value at the time of the accident may be calculated (S102).

  In the above description, the wear rate is obtained, and the internal inspection is performed when the estimated cumulative wear rate exceeds a predetermined value. However, the wear rate may be managed.

  Next, a second embodiment of the present invention will be described. FIG. 6 is a functional block diagram of the contact wear monitoring system 1 according to the present embodiment.

  In this figure, a contact wear monitoring system 1 includes a plurality of breaking current grasping devices 20 installed in the field, a customer terminal 35, and a contact wear monitoring server (hereinafter referred to as a server) connected to these via a communication network 40. 50.

  The breaking current grasping device 20 is installed not only at the electric power company but also at the electric power consumer or generator side where the breaker is installed. In addition, the server 50 is operated by a supplier that provides a maintenance support service for power equipment.

  The configuration of the breaking current grasping device 20 is basically the same as that of FIG. 1, but includes a communication interface for connecting to other devices via the communication network 40 instead of the level converter 28.

  The contact wear and tear monitoring server 50 includes an input unit 53 and an output unit 52 for inputting / outputting data, a central processing unit 60 for executing data processing, a storage unit 80 for storing data, and communication A transmission / reception unit 51 for communicating with other devices via the network 40 is configured.

  Further, the central processing unit 60 includes transmission / reception processing means (function) 61 for executing transmission / reception processing, input / output processing means (function) 62 for transferring data between the input unit 13 and the output unit 52, and an input unit 53. Basic information registration means (function) 64 for storing the basic information of the circuit breaker input via the storage unit 80 in the storage unit 80, customer information registration means (function) 63 for registering customer information, grasping the breaking current installed on the customer side Electrical data input means (function) 65 for inputting electrical data such as a current waveform sent from the device 20, estimated cumulative wear rate calculation means (function) 66 for calculating the estimated cumulative wear rate of the circuit breaker, estimated cumulative wear rate Calculation result transmission means (function) 67 for transmitting the calculation results of the above to the customer terminal 35, and inspection information input means (machines) for inputting inspection information such as the weight information of the arc contact wear parts collected by the internal inspection of the circuit breaker 68) and a measured cumulative wear rate calculating means (function) 69 for calculating the measured cumulative wear rate using the inspection information.

  The storage unit 80 also includes a customer information database (DB) 81 for storing customer information, a basic information database (DB) 82 for storing circuit breaker specification information, and device information for storing individual information on the customer circuit breaker. A database (DB) 83 is provided.

Next, the operation of the contact wear monitoring system 1 will be described.
First, the basic information of the circuit breaker is input from the input unit 53. This information is stored in the basic information DB 82 of the storage unit 80 by the basic information registration means 64. In addition, information on a customer who wants to subscribe to a service provided by a supplier is input from the customer terminal 35 and stored in the customer information DB 81 of the storage unit 80 by the customer information registration unit 63. At the same time, an area for storing customer circuit breaker information is taken in the device information DB 82.

  Examples of data structures of the customer information DB 81, basic information DB 82, and device information 82 are shown in FIGS. 7, 8, and 9, respectively.

  In the customer information DB 81, as shown in FIG. 7, a customer ID is obtained by registration for the maintenance service, and customer attribute information such as a customer name and an e-mail address is stored. The basic information DB 82 and device information 83 shown in FIGS. 8 and 9 are different from the electrode characteristic data (FIG. 4) and device specific data (FIG. 5) shown in the first embodiment in that the device information is The identification information (ID) is attached to each customer device, and the wear rate comparison value for determining the internal inspection time is managed in the device information DB as a value that can be set by the customer within a certain range. In addition to the calculation at the time of the accident trip this time, the value of the predicted calculation result of the wear rate at the next accident can be stored based on the average value so far. This allows the customer to budget for internal inspection costs in advance.

  When the customer's breaker breaks down, the current waveform information at that time is sent from the breaking current grasping device 20 and stored in association with the device information via the electric data input means 65. Then, the estimated cumulative wear rate calculating means 66 is activated, and the calculation formula ((1) or (2)) of the breaking current is selected and selected based on the device information of the circuit breaker that has been interrupted. The breaking current value is calculated by the equation. The arc time is calculated from the current waveform and the timing of the trip signal. Then, with reference to the basic information of the device (design arc time, rated breaking current, etc.), the estimated cumulative wear rate is calculated using equation (3). Since this calculation method is the same as that in the first embodiment, a description thereof will be omitted.

  When the calculation of the estimated cumulative wear rate is completed, the calculation result transmitting means 67 is activated and the calculation result is sent to the terminal 35 of the customer. The calculation results include the estimated cumulative wear rate value, the determination result when compared with the wear rate comparison value (management value), the wear rate at the next accident interruption, and the like. When the wear rate exceeds the control value, a warning message is sent that requires internal inspection.

  The customer performs the internal inspection by this caution message, or requests the manufacturer or maintenance company to perform the inspection. Then, inspection information such as the arc contact wear amount weight is input from the customer terminal 35 and stored in the corresponding area of the customer device in the device information DB 83 by the inspection information input means 68. When inspection is performed by dismantling, a dismantling flag is set at the same time.

  Thereafter, the measured cumulative wear rate calculating means 69 is activated, the measured cumulative wear rate is calculated by equation (4), and the coefficient β value is calculated by equation (5). Then, the β value stored as the basic information of the device is rewritten. In this rewriting, the calculated β value is not rewritten as it is, but for example, the stored β value and the currently calculated β value may be stored as new β values. Further, when the calculated β value exceeds a predetermined range, it is not used or a limit value within the predetermined range is used. By correcting the β value calculated in this way, it is possible to prevent an error from becoming larger due to environmental conditions or the like.

  According to the present embodiment, the coefficient β of the estimated cumulative wear level of the circuit breaker contact is corrected by actual measurement. Therefore, the error of the estimated cumulative wear level due to the difference in the measurement method of the break current is absorbed and the contact wear is highly accurate. The degree can be estimated, and the customer having the circuit breaker can be effectively notified of the maintenance time of the circuit breaker.

  In particular, for each customer, there is almost no opportunity for internal inspection of the circuit breaker based on the cumulative wear rate, but the above-mentioned circuit breaker maintenance support service increases the number of data. A high β value can be used, and the calculation method of the breaking current can be unified for each device type, so that the accuracy of the estimated cumulative wear rate can be improved.

  The internal inspection of the circuit breaker may be performed by this maintenance support service provider. In this case, inspection information is input from the input unit 53. In addition, it is possible to make a tie-up with a maintenance company of a power device such as a circuit breaker and connect to the maintenance company's server to adjust the maintenance schedule.

  Also, since the data sent from the breaking current grasping device 20 may be any information that can calculate the arc time and breaking current information, instead of the raw current waveform data and the trip timing signal on the time axis, The arc time and the breaking current value itself may be used. In this case, for example, if the server 50 transmits the setting information as to whether the cutoff current is calculated according to either the formula (1) or the formula (2) based on the device type, to the cutoff current grasping device 20, Since appropriate cut-off current information is sent from the device 20, the load on the server 50 can be reduced.

It is a functional block diagram of the contact wear monitoring system concerning a 1st embodiment in the present invention. 6 is a flowchart for explaining the operation of the contact wear monitoring system. It is a figure showing calculation of the breaking current in an asymmetrical current and a general waveform. It is explanatory drawing of the electrode characteristic data in the 1st Embodiment of this invention. It is explanatory drawing of the apparatus specific data in the 1st Embodiment of this invention. It is a functional block diagram of the contact wear monitoring system in the 2nd Embodiment of this invention. It is a data structural example of customer information DB in FIG. It is an example of a data structure of basic information DB in FIG. It is a data structural example of apparatus information DB in FIG.

Explanation of symbols

1 Contact wear monitoring system 4 Communication line 5 Main circuit 6 Main circuit current transformer 7 Auxiliary current transformer 8 TC (trip coil)
9 Auxiliary contact 10 Computer device 20 Breaking current grasping device 21 Input conversion unit 22 23 Transducer 24 Impedance conversion unit 25 AD conversion / calculation unit 26 AD conversion unit 27 CPU unit 28 Level converter 29 Clock unit 30 Storage device 31 Power supply (power failure compensation type) )
35 Customer terminal 40 Communication network 50 Contact wear monitoring server 51 Transmission / reception unit 52 Output unit 53 Input unit 60 Central processing unit 61 Transmission / reception processing unit 62 Input / output processing unit 63 Customer information registration unit 64 Basic information registration unit 65 Electrical data input unit 66 Estimated cumulative wear rate calculation means (estimated cumulative wear rate calculation means)
67 Calculation result transmission means 68 Inspection input means 69 Actual cumulative wear rate calculation means (actual cumulative wear degree calculation means)
80 storage unit 81 customer information DB
82 Basic information DB
83 Device information DB

Claims (8)

Means for inputting electrical information of the main circuit;
Means for inputting a trip signal for the circuit breaker;
An arc time and breaking current are calculated using the electrical information and the trip signal, and an estimated cumulative wear rate Bc of the circuit breaker is calculated by the following equation (A) using a coefficient initial value β. Computing means;
Determination means for determining whether the estimated cumulative wear rate Bc is equal to or greater than a predetermined value and outputting the determination result;
Input the actual wear amount information of the arc contactor of the circuit breaker, and obtain the measured cumulative loss rate Bf by the following equation (B):
A measured cumulative wear rate calculating means for correcting the coefficient initial value β by calculating a coefficient β in the measured cumulative wear rate Bf by the following equation (C) :
A circuit breaker contact wear monitoring system characterized by comprising:   2. The circuit breaker contact wear monitoring system according to claim 1, wherein the circuit breakers are grouped based on an operation specification and a voltage class, and the coefficient [beta] is corrected independently for each group.   2. The circuit breaker contact wear monitoring system according to claim 1, wherein in the calculation of the estimated cumulative wear rate, it is possible to select whether the breaking current is obtained as an asymmetrical breaking current or an effective value of a general waveform. The arc time and breaking current information sent from the breaking current grasping device installed on the customer side is input to the server via the communication network, the wear rate of the breaker arc contactor is calculated, and the calculation result is sent to the customer terminal. Circuit breaker maintenance support method,
In the server,
Using the arc time , the breaking current, and the coefficient initial value β , calculating an estimated cumulative wear rate Bc of the breaker according to the following equation (A) :
Determining whether the estimated cumulative wear rate Bc is equal to or greater than a predetermined value and transmitting the determination result to the customer terminal;
The actual wear amount information of the arc contactor of the circuit breaker is input, and the measured cumulative wear rate Bf is calculated by the following equation (B).
Calculating the coefficient β in the measured cumulative wear rate Bf by the following formula (C) to correct the coefficient initial value β;
The circuit breaker maintenance support method characterized by including.   5. The circuit breaker maintenance support method according to claim 4, wherein, in the calculation of the estimated cumulative wear rate, whether to obtain the breaking current as an asymmetrical breaking current or an effective value of a general waveform is selected based on an operating specification of the breaker. .   5. The circuit breaker maintenance support method according to claim 4, further comprising the step of setting, from a customer terminal, the predetermined value when determining whether the estimated cumulative wear rate is equal to or greater than a predetermined value.   The method includes a step of outputting a message as to whether an internal inspection is performed by disassembly or an X-ray diagnosis is performed based on a voltage class of the circuit breaker when the estimated cumulative wear rate exceeds a predetermined value. The circuit breaker maintenance support method according to any one of 4 to 6. A program that operates on a computer that inputs arc time and breaking current information and calculates the wear rate of the breaker arc contactor,
Using the arc time , the breaking current, and the coefficient initial value β , a process for calculating an estimated cumulative wear rate Bc of the breaker according to the following equation (A) :
A process of determining whether the estimated cumulative wear rate Bc is equal to or greater than a predetermined value and outputting the determination result;
The actual wear amount information of the arc contactor of the circuit breaker is input, and the measured cumulative wear rate Bf is calculated by the following equation (B).
Processing for correcting the coefficient initial value β by calculating the coefficient β in the measured cumulative wear rate Bf by the following equation (C) :
A program that executes.