KR101634634B1 - Motor protection relay capable of calibration self diagnosis and correction - Google Patents

Motor protection relay capable of calibration self diagnosis and correction Download PDF

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Publication number
KR101634634B1
KR101634634B1 KR1020150051871A KR20150051871A KR101634634B1 KR 101634634 B1 KR101634634 B1 KR 101634634B1 KR 1020150051871 A KR1020150051871 A KR 1020150051871A KR 20150051871 A KR20150051871 A KR 20150051871A KR 101634634 B1 KR101634634 B1 KR 101634634B1
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KR
South Korea
Prior art keywords
correction coefficient
motor protection
protection relay
processor
preset
Prior art date
Application number
KR1020150051871A
Other languages
Korean (ko)
Inventor
윤재준
Original Assignee
엘에스산전 주식회사
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Priority to KR1020150051871A priority Critical patent/KR101634634B1/en
Application granted granted Critical
Publication of KR101634634B1 publication Critical patent/KR101634634B1/en

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
    • G01R31/3277—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches
    • G01R31/3278—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches of relays, solenoids or reed switches
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
    • G01R19/16504—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the components employed
    • G01R19/16509—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the components employed using electromagnetic relays, e.g. reed relay
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M1/00—Analogue/digital conversion; Digital/analogue conversion
    • H03M1/001—Analogue/digital/analogue conversion

Abstract

The present invention provides a motor protecting relay with a calibration coefficient self-diagnosis function which is capable of automatically diagnosing a change in a calibration coefficient. The motor protecting relay according to an embodiment of the present invention comprises: an electric quantity detecting unit which detects a current and a voltage supplied to a motor; an analog-digital converter which converts an analog signal, which represents the electric quantity from the electric quantity detecting unit, to a digital signal; and a processor which processes electric quantity detection data provided from the analog-digital converter, calculates a difference value between a preset calibration coefficient used for calibrating the electric quantity detection data and a preset reference calibration coefficient, and determines whether the preset calibration coefficient is allowable according to whether the calculated difference value falls within a preset error percentage.

Description

{MOTOR PROTECTION RELAY CAPABLE OF CALIBRATION SELF DIAGNOSIS AND CORRECTION}

The present invention relates to a motor protection relay, and more particularly, to an electronic motor protection relay and a correction factor self-diagnosis and correction method of an electromagnetic motor protection relay capable of self-diagnosis and correction of correction coefficient.

The electronic motor protection relay determines whether or not an abnormal condition occurs in the power circuit supplied to the motor based on the detection data of the current and voltage of the power supplied to the motor as well as the operation and stoppage control of the motor. A relay capable of protecting the motor by interrupting the power supply when a state occurs, including a digital input / output and processing device and a display device, is a relay capable of providing and displaying digital data.

An example of the prior art in such an electronic motor protection relay (hereinafter abbreviated as a motor protection relay) will be described with reference to Fig.

FIG. 1 is a block diagram showing a main configuration of a motor protection relay according to the related art. As shown in FIG. 1, a motor protection relay according to the related art detects a current and a voltage of a power supplied to a motor, A converter 10, an analog-to-digital converter 20, and a processor 30.

The electric quantity detection unit 10 includes a current transformer that is electrically connected to a power supply line between a power source to which the motor protection relay is connected and a power supply line between the load and the load (normal motor) to detect and provide an amount of current flowing in the load, A voltage transformer or a shunt resistor that detects and provides a phase voltage.

The analog-to-digital converter 20 is connected between the output terminal of the electricity quantity detection unit 10 and the processor 30 and is constituted by an analog-digital conversion circuit. The analog-digital converter 20 digitally detects the analog electric quantity detection signal output from the electricity quantity detection unit 10 Signal to the processor 30.

The processor 30 processes the data by a processing program stored in advance on the basis of the digital detection signal provided by the analog-to-digital converter 20, thereby calculating meaningful (valuable as the electricity quantity detection data) electricity quantity measurement information data.

At this time, the processor 30 calibrates the electricity quantity detection data by performing arithmetic operation with a predetermined correction coefficient and uses the calibration data.

The correction coefficient is set at the time of manufacture of the motor protection relay according to the prior art and is used without modification at the installation site of the motor protection relay.

However, when the temperature changes during installation and use, and due to influences from the inside and outside of the motor protection relay such as a power failure, the electricity quantity data processed and acquired by the processor 30 becomes meaningless information and based on the acquired electricity quantity data There is a problem in that the operation of the operating motor protection relay may cause a malfunction or damage such as a power supply to the motor is cut off unnecessarily.

SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to provide a motor protection relay capable of self-diagnosis of a correction coefficient capable of automatically diagnosing a correction coefficient when it is altered.

A second object of the present invention is to provide a motor protection relay capable of automatically correcting a correction coefficient when it is altered.

A third object of the present invention is to provide a correction coefficient self diagnosis and correction method of a motor protection relay capable of automatically diagnosing a correction coefficient when it is altered.

A fourth object of the present invention is to provide a correction coefficient self-diagnosis and correction method of a motor protection relay capable of automatically correcting a correction coefficient when it is altered.

A first object of the present invention is to provide a motor protection relay capable of self-diagnosis and correction of correction coefficient,

An electricity amount detecting unit for detecting a current and a voltage provided to the motor;

An analog-to-digital converter connected to the electricity quantity detection unit and converting an analog signal representing the electricity quantity from the electricity quantity detection unit into a digital signal; And

A converter connected to an output terminal of the analog-to-digital converter for processing electrical quantity detection data provided by the analog-

A processor (PROCESSOR) for determining the allowability of a preset correction coefficient according to whether a comparison operation value between a preset correction coefficient and a preset reference correction coefficient is within a predetermined error range for calibration of the electricity amount detection data; The motor protection relay according to the present invention.

A second object of the present invention is to provide a processor,

When the comparison operation value is not within the predetermined error range,

A preset average correction coefficient is set and stored as the changed correction coefficient,

And a correction coefficient to be set by the user is set to a modified correction coefficient and stored. The motor protection relay according to the present invention can be achieved by providing the motor protection relay according to the present invention.

A third object of the present invention is to provide a correction coefficient self-diagnosis and correction method for a motor protection relay,

A reference correction coefficient storage step of storing, as a reference correction coefficient, an average correction coefficient of mass production samples of a plurality of motor protection relays in which the processor included in the motor protection relay is set;

Calculating a difference value between the reference correction coefficient and a preset correction coefficient to be applied to the detected electricity amount data, and determining whether the calculated difference value is within a predetermined allowable error percentage; And

And a correction coefficient nonconformity reporting step of informing a user of the nonconformity of the correction coefficient so that the user can take an action when the difference calculated in the correction coefficient error determination step is not within a predetermined allowable error percentage And a correction coefficient self-diagnosis and correction method of the motor protection relay according to the present invention.

A fourth object of the present invention is to provide a method and an apparatus for correcting a change of a correction coefficient when a user confirms a change of a preset correction coefficient in a correction coefficient maintenance / And a correction coefficient changing step of changing the setting or storing the previously stored average correction coefficient as a new setting data of the correction coefficient by changing the setting of the correction coefficient by the processor, Can be achieved by providing a correction factor self-diagnosis and correction method of the motor protection relay.

According to a preferred aspect of the present invention, when the comparison operation value is not within a predetermined tolerance range, the processor may display the correction coefficient suitability information through the display device or may be corrected by a device external to the motor protection relay through communication And transmits the coefficient conformance information or outputs the correction coefficient conformance information through the output port.

According to another preferred aspect of the present invention, the average correction coefficient is an average correction coefficient of mass production samples of a plurality of motor protection relays.

According to another preferred aspect of the present invention, the correction coefficient nonconformity reporting step includes: displaying and reporting the correction coefficient nonconformity status through the display device; reporting the correction coefficient nonconformity status data to the outside of the motor protection relay And outputting correction coefficient nonconformity state data through a digital output terminal of the motor protection relay to report correction coefficient nonconformity state data.

According to still another aspect of the present invention, a correction coefficient self-diagnosis and correction method of a motor protection relay according to the present invention includes: And a correction coefficient maintenance / change confirmation step of confirming the user's decision.

The motor protection relay according to the present invention includes a processor for calculating a difference between a preset correction coefficient and a preset reference correction coefficient and determining a tolerance of a preset correction coefficient according to whether the calculated difference value is within a predetermined error percentage, (PROCESSOR), it is possible to provide the effect of self-diagnosing whether the predetermined correction factor is acceptable or not, depending on whether the calculated difference value is within a predetermined error percentage.

In the motor protection relay according to the present invention, when the computed difference value is not within a predetermined error percentage, the processor sets the preset average correction coefficient as a changed correction coefficient and stores the corrected average correction coefficient as a correction It is possible to provide an effect that the correction coefficient can be automatically corrected when the correction coefficient is not within the allowable normal range.

In the motor protection relay according to the present invention, when the calculated difference value is not within a predetermined error percentage, the processor displays the information through a display device, or transmits information Or output an information signal indicating the digital output through the digital output, thereby providing an effect of automatically reporting to the user.

The motor protection relay according to the present invention is characterized in that when the average correction coefficient of mass production samples of a plurality of motor protection relays is applied as a reference correction coefficient and there is a change in a preset correction coefficient, It is possible to provide the effect of determining whether the correction coefficient can be used or not by the inclusion in the allowable range.

A correction coefficient self diagnosis and correction method of a motor protection relay according to the present invention includes a reference correction coefficient storage step of storing an average correction coefficient of mass production samples of a plurality of motor protection relays for which a processor is set as a reference correction coefficient, A correction coefficient error determination step of calculating a difference value between a preset correction coefficient to be applied and the reference correction coefficient and determining whether the calculated difference value is within a predetermined allowable error percentage; Is not within a predetermined allowable error percentage, it includes a correction coefficient nonconformity status reporting step of informing the user of the nonconformity status of the correction coefficient so that the user can take an action. Therefore, Diagnosis is possible and use is in a non-compliant state It can provide the effect of automatically reporting this to the user and taking action.

The correction coefficient self diagnosis and correction method of the motor protection relay according to the present invention is characterized in that when it is confirmed that the user has decided to change the preset correction coefficient, And a correction coefficient changing step of changing the setting of the correction coefficient stored in advance or storing the previously stored average correction coefficient as new correction data of the correction coefficient, It is possible to provide an effect that can be newly stored and applied with the correction coefficient directly inputted.

In the correction coefficient self-diagnosis and correction method of the motor protection relay according to the present invention, the correction coefficient nonconformity status reporting step may include: displaying and reporting a correction coefficient nonconformity status through a display device; And reporting the correction coefficient nonconformity status data by outputting the correction coefficient nonconformity status data through the digital output terminal of the motor protection relay to report the correction coefficient nonconformity status data. Therefore, the display through the digital- It is possible to provide an effect of reporting to the user the nonconformity state of the preset correction coefficient by the status output through the digital output terminal or via communication or through the digital output terminal.

The correction coefficient self-diagnosis and correction method of the motor protection relay according to the present invention can confirm whether or not to keep the predetermined correction coefficient by means of the user's input to the processor of the motor protection relay through the input means, / Change can be confirmed.

1 is a block diagram showing a configuration of a motor protection relay according to the related art,
FIG. 2 is a block diagram showing a configuration of a motor protection relay according to a preferred embodiment of the present invention,
FIG. 3 is a flow chart of a request configuration and data processing showing a data processing flow of the processor,
4 is a flowchart showing a correction coefficient correction method of a motor protection relay according to a preferred embodiment of the present invention.

The above and other objects, features and advantages of the present invention will become more apparent from the following description of the preferred embodiments of the present invention with reference to the accompanying drawings.

2, the motor protection relay capable of self-diagnosis and correction of the correction coefficient according to the preferred embodiment of the present invention includes an electricity quantity detecting unit 10, an analog-to-digital converter 20, and a processor PROCESSOR 30). 1 and 2, there is no difference in the configuration of the motor protection relay according to the present invention and the conventional motor protection relay according to the present invention. However, it indicates that the software configuration executed by the processor, that is, the processing configuration according to the program, is different from the prior art.

The electric quantity detecting unit 10 is a means for detecting a current and a voltage provided to the motor, and includes a current transformer electrically connected to a power supply line between a power source and a motor to detect and provide an amount of current flowing in the load, A voltage transformer or a shunt resistor for detecting and providing a voltage.

The analog-to-digital converter 20 is connected to the electricity quantity detecting unit 10 and converts the analog signal representing the electricity quantity from the electricity quantity detecting unit 10 into a digital signal.

The processor 30 is connected to the output terminal of the analog-to-digital converter 20 and processes electrical quantity detection data provided by the analog-to-digital converter 20. [ The processor 30 calculates a difference between a preset correction coefficient and a preset reference correction coefficient for calibration of the electricity quantity detection data. According to one embodiment of the present invention, processor 30 may be configured to determine the allowability of a preset correction factor, depending on whether the calculated difference value is within a predetermined error percentage (e.g., 3% of the reference correction factor) have.

The processor 30 includes a memory having a processing program and a microprocessor including a central processing unit for reading the processing program from the memory and executing the processing program to process the electricity amount detection data provided by the analog- And a processor (aka microcomputer).

When the calculated difference value is not within a predetermined error percentage, the processor 30 controls to display it through a display device (not shown) or communicates with a device (for example, an upper monitoring device) (For example, by outputting to the connected notebook computer) an information signal indicating the information through a digital output and reporting the information to the user.

The processor 30 may also set and store a predetermined average correction coefficient as a changed correction coefficient when the calculated difference value is not within a predetermined error percentage or may set the correction coefficient manually set by the user as a changed correction coefficient For example.

According to a preferred embodiment, the average correction coefficient is composed of an average correction coefficient of a plurality of motor protection relay mass production samples (random samples produced at the manufacturing factory of the motor protection relay, that is, an average value of correction coefficients of the corresponding samples) .

The predetermined average correction coefficient may be a value that is sampled and averaged as an average correction coefficient of the mass production samples and is provided as product description information (data) through, for example, a manufacturer's Internet home page of the motor protection relay. The user can find the corresponding information (average correction coefficient) on the home page and input it to the motor protection relay through input means (for example, a key switch) of the motor protection relay, and the processor 30 sends the information to the motor protection relay The average correction coefficient may be set as a reference correction coefficient or a new correction coefficient by being stored in a memory means such as an included flash memory.

The user can directly input the correction coefficient to the motor protection relay via the input means of the motor protection relay as described above, By storing the information in the memory means included in the motor protection relay, the correction coefficient directly input by the user can be set as the reference correction coefficient or the new correction coefficient.

The operation of the motor protection relay capable of self-diagnosis and correction of the correction coefficient according to the preferred embodiment of the present invention constructed as described above and the correction factor self-diagnosis and correction method of the motor protection relay according to the preferred embodiment of the present invention, Referring to FIG. 4, the flow chart of FIG.

3, the correction coefficient self-diagnosis and correction method of the motor protection relay according to the preferred embodiment of the present invention includes a reference correction coefficient storage step S1, a correction coefficient error determination step S2 and a non- Step S3.

In the reference correction coefficient storage step S1, an average correction coefficient of mass production samples of a plurality of motor protection relays set by the processor 30 included in the motor protection relay is stored as a reference correction coefficient.

In this case, as described above, the user inputs the average correction coefficient by searching the home page for the corresponding information (average correction coefficient) and inputting the input means (for example, a key switch, a key pad, etc.) Lt; RTI ID = 0.0 > a < / RTI > motor protection relay. Further, the storage as the reference correction coefficient can be achieved by the processor 30 storing the information (average correction coefficient) in a memory means such as a flash memory included in the motor protection relay.

In the correction coefficient error determination step S2, the processor 30 calculates a difference between a preset correction coefficient to be applied to the detected electricity amount data and the reference correction coefficient, that is, the average correction coefficient, A value within an acceptable percentage error (e.g., 3% of the reference correction factor) (i.e., an acceptable percentage error is an acceptable error percentage value or less). Here, the preset correction coefficient is a correction coefficient which is inputted through the input means at the manufacturing factory at the time of manufacturing the motor protection relay and stored by the processor 30.

If the difference calculated in the correction coefficient error determination step S2 is not within the predetermined allowable error percentage, i.e., exceeds the allowable error percentage, the user is informed of the non-conformance status of the correction coefficient so that the user can take an action (S3).

The correction coefficient nonconformity status reporting step (S3) may include displaying the correction coefficient nonconformity status through a display device (not shown) or reporting the correction coefficient nonconformity status data to the outside of the motor protection relay, And outputting the correction coefficient nonconformity status data through a digital output terminal (not shown) of the protection relay to report the correction coefficient nonconformity status data.

In FIG. 3, the data displayed at the bottom, the correction coefficients, and the blocks of the information indicate the process in which the electricity amount detection data is converted into valuable information whose arithmetic processing is performed to correct the error, as described below.

That is, the block indicated by the data indicates that the electricity quantity detection data from the electricity quantity detecting section 10 is input to the processor 30 through the analog-digital converter 20. [

The block indicated by the correction coefficient indicates a process in which the electricity amount detection data is calculated and processed by the processor 30 with the correction coefficient.

Finally, the block indicated by the information represents the step of converting the electricity amount detection data into the valuable information reflecting the correction coefficient after the calculation processing with the correction coefficient by the processor 30.

Meanwhile, the correction coefficient self diagnosis and correction method of the motor protection relay according to the preferred embodiment of the present invention may further include a correction coefficient maintenance / change confirmation step (S3-1) as shown in FIG.

Will be described with reference to FIG.

In the correction factor maintenance / change confirmation step (S3-1), the processor 30 determines whether or not a predetermined correction coefficient (i.e., the motor protection relay is inputted through the input means at the manufacturing factory in the manufacture of the motor protection relay, Correction factor) or confirms the user's decision to be input to the processor 30 of the motor protection relay via the input means.

The correction coefficient self-diagnosis and correction method of the motor protection relay according to the preferred embodiment of the present invention may further include a correction coefficient changing step (S3-2).

That is, when it is confirmed that the user has decided to change the preset correction coefficient in the correction coefficient maintenance / change confirmation step (S3-1), the processor 30 sets the correction coefficient, which is directly inputted by the user through the input means, Or the processor 30 changes and stores the setting of the correction coefficient as the new correction data of the correction coefficient set as described above.

If it is determined in the correction coefficient maintenance / change confirmation step (S3-1) that the user has decided to hold the preset correction coefficient, the processor 30 terminates the processing without any additional processing so as to maintain the preset correction coefficient do.

As described above, the motor protection relay according to the present invention calculates a difference between a preset correction coefficient and a predetermined reference correction coefficient, and determines whether or not the calculated difference is within a predetermined error percentage, It is possible to provide an effect of self-diagnosing the allowability of a predetermined correction coefficient, that is, whether or not the correction coefficient is altered, depending on whether the calculated difference value is within a predetermined error percentage.

In the motor protection relay according to the present invention, when the computed difference value is not within a predetermined error percentage, the processor sets the preset average correction coefficient as a changed correction coefficient and stores the corrected average correction coefficient as a correction It is possible to provide an effect that the correction coefficient can be automatically corrected when the correction coefficient is not within the allowable normal range.

10: electricity quantity detecting unit 20: analog-to-digital converter
30: Processor

Claims (5)

In a motor protection relay capable of self-diagnosis and correction,
An electricity amount detecting unit for detecting a current and a voltage provided to the motor;
An analog-to-digital converter connected to the electricity quantity detection unit and converting an analog signal representing the electricity quantity from the electricity quantity detection unit into a digital signal; And
A converter connected to an output terminal of the analog-to-digital converter for processing electrical quantity detection data provided by the analog-
A processor (PROCESSOR) for determining the allowability of a preset correction coefficient according to whether a comparison operation value between a preset correction coefficient and a preset reference correction coefficient is within a predetermined error range for calibration of the electricity amount detection data; Lt; / RTI >
The processor comprising:
When the comparison operation value is not within the predetermined error range,
A preset average correction coefficient is set and stored as the changed correction coefficient,
Wherein the controller is configured to set the correction coefficient inputted by the user and set the inputted correction coefficient to the changed correction coefficient. The method according to claim 1,
The processor comprising:
If the comparison operation value is not within the predetermined error range,
Display correction factor suitability information via a display device,
Communication can be used to transfer calibration factor compliance information to devices outside the motor protection relay,
And outputs the correction coefficient conformity information through an output port of the motor protection relay. delete The method according to claim 1,
The average correction coefficient is calculated by:
Wherein the motor protection relay is an average correction coefficient of mass production samples of a plurality of motor protection relays. The method according to claim 1,
The processor comprising:
A difference value between a preset correction coefficient and a preset reference correction coefficient is calculated and the allowability of a preset correction coefficient is determined according to whether or not the calculated difference value is within a predetermined error percentage.
KR1020150051871A 2015-04-13 2015-04-13 Motor protection relay capable of calibration self diagnosis and correction KR101634634B1 (en)

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KR101634634B1 true KR101634634B1 (en) 2016-06-29

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007287290A (en) * 2006-04-20 2007-11-01 Hitachi Global Storage Technologies Netherlands Bv Disk drive and its calibration method
KR20090062916A (en) * 2007-12-13 2009-06-17 엘에스산전 주식회사 Electronic motor protection relay and control method thereof
KR20110068222A (en) * 2009-12-15 2011-06-22 엘에스산전 주식회사 Digital protection relay

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007287290A (en) * 2006-04-20 2007-11-01 Hitachi Global Storage Technologies Netherlands Bv Disk drive and its calibration method
KR20090062916A (en) * 2007-12-13 2009-06-17 엘에스산전 주식회사 Electronic motor protection relay and control method thereof
KR20110068222A (en) * 2009-12-15 2011-06-22 엘에스산전 주식회사 Digital protection relay

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