CN106066445B - Open triangular loop broken line monitoring device of voltage transformer and application method - Google Patents
Open triangular loop broken line monitoring device of voltage transformer and application method Download PDFInfo
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- CN106066445B CN106066445B CN201610432911.0A CN201610432911A CN106066445B CN 106066445 B CN106066445 B CN 106066445B CN 201610432911 A CN201610432911 A CN 201610432911A CN 106066445 B CN106066445 B CN 106066445B
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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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
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Abstract
The invention discloses a voltage transformer opening triangle loop disconnection monitoring device and an application method thereof, wherein the device comprises a totally-enclosed case and an installation fixing lug, and is characterized in that: a display screen is arranged on the front panel surface of the totally-enclosed case; an operation keyboard is arranged on the lower side of the display screen; a signal indicator lamp is arranged on the right side of the display screen; a PCB main board is arranged in the totally-enclosed case; the upper side of the rear wall of the totally-enclosed case is provided with a secondary circuit voltage wiring terminal block of a 10KV bus; a 485 communication terminal strip is arranged on the lower side of the rear wall of the totally-enclosed case; the right side of the back wall of the totally-enclosed case is provided with an Ethernet interface. The device and the application method can timely send out alarm information and report to the dispatching master station when the open triangular secondary circuit breaks, so that maintenance personnel can process the alarm information conveniently, and hidden danger in equipment operation is eliminated; the reliability and the sensitivity of the monitoring result of the device are ensured, and the defect-free operation of the open triangular loop is ensured.
Description
Technical Field
The invention relates to an improvement of a secondary voltage monitoring device of a voltage transformer, in particular to a broken line monitoring device of an open triangular loop of the voltage transformer and an application method.
Background
The auxiliary secondary windings of the voltage transformer are connected end to end in sequence according to the triangular wiring, but are not closed, namely an open triangular loop; open triangular voltage 3U of voltage transformer 0 The voltage is formed by sequentially connecting the secondary windings of the three-phase transformer end to end, and as shown in fig. 6, ua vectors, ub vectors and Uc vectors are connected end to end in a triangular shape, but are not closed. When the open delta winding of the voltage transformer is normally operated under load of equipment, the port voltage is basically 1-2V, the secondary end voltage of part of the open delta winding is zero, and when the secondary circuit of the open delta winding has fuse breakdown damage or circuit disconnection, as A, B, C three-phase voltage is normal, and the open delta voltage has induced voltage, the circuit disconnection is not easy to be perceived, and whether the existing 10kV circuit protection device or the small-current grounding line selection device can accurately judge whether the open delta winding secondary circuit is disconnected or not. If a single-phase earth fault of the neutral point ungrounded system occurs, the relative ground voltage of the fault is zero, and the relative ground voltage of the non-fault is increased to be original
Multiple of opening triangle voltage 3U 0 The voltage is zero after the disconnection, and the existing small-current grounding line selection device cannot judge a fault bus due to the fact that the opening triangular voltage is zero, so that potential safety hazards are brought to the grounding line selection function of equipment.
As can be seen from the search, chinese patent CN104535956a discloses a method for detecting the wiring/polarity correctness of the secondary open delta loop of a voltage transformer, which can solve the problem of zero sequence protection malfunction or refusal action caused by the polarity error of the open delta, and can not timely and accurately send out alarm information when the open delta secondary loop breaks. At present, no report of a device which can timely and accurately judge the wire breakage position and send alarm information to a dispatching master station in time so as to be convenient for maintenance personnel to make treatment when the wire breakage occurs in an open triangular secondary circuit is yet seen.
Disclosure of Invention
The invention aims to provide the voltage transformer opening triangular loop disconnection monitoring device which is friendly in interaction interface, accurate in judgment and convenient to install in later transformation. The open triangular loop disconnection monitoring device of the voltage transformer and the application method thereof can monitor and record three-phase voltage and zero sequence voltage in real time, can timely and accurately send out alarm information and report to a dispatching master station when disconnection occurs in an open triangular secondary loop so as to facilitate maintenance staff to process, and eliminate hidden danger in equipment operation.
Another object of the present invention is to provide an application method of the open delta loop disconnection monitoring device for a voltage transformer for achieving the above object.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: this voltage transformer opening triangle return circuit broken string monitoring devices, including the installation fixed ear at totally closed machine case and both ends, its characterized in that: an initialization information liquid crystal display screen is arranged on the front panel surface of the totally-enclosed case; an operation keyboard is arranged on the lower side of the initialization information liquid crystal display screen; a signal indicator lamp is arranged on the right side of the initialization information liquid crystal display screen; a PCB main board provided with a communication unit, a main control unit, a voltage sensor data acquisition unit and a power module is arranged in the totally-enclosed case; the upper side of the rear wall of the totally-enclosed case is provided with a secondary circuit voltage wiring terminal block of a 10KV bus; a 485 communication terminal strip is arranged on the lower side of the rear wall of the totally-enclosed case; an Ethernet interface is arranged on the right side of the rear wall of the totally-enclosed case; the voltage sensor data acquisition unit, the power supply module and the operation keyboard are connected to the main control unit, and the main control unit is connected to the initialization information liquid crystal display screen and the communication unit; the communication unit sends the data to the communication equipment through a serial port or an Ethernet interface; voltage sensor data acquisition listU of secondary circuit voltage wiring terminal strip for primary collection 10KV bus L Phase, U LN The voltage data of the phases Ua, ub, uc and Un are converted into A, B, C three-phase voltage and opening triangular voltage by a voltage transformer data acquisition unit after second-order low-pass filtering, the voltage transformer data acquisition unit is converted into digital signals, the digital signals are input into a main control unit, the main control unit formed by a high-performance Blackfin series processor and a memory carries out processing logic judgment on the digital signals, and the main control unit displays the judged current bus voltage and various parameter information results through an initialization information liquid crystal display screen and sends the signals to communication equipment of a dispatching main station through a communication unit.
The invention is also implemented by the following measures: the operation keyboard comprises a return key, a down key, an up key and a determination key, and has different functions under different menu environments, and is mainly used for parameter setting, menu switching and user interactive operation information.
The power supply module is connected with a 220V alternating current/direct current power supply.
The signal indicator lamps are four, namely an operation indicator lamp, a disconnection indicator lamp, an alarm indicator lamp and a communication indicator lamp, and are all connected with a circuit of the main control unit.
The application method of the open triangular loop disconnection monitoring device of the voltage transformer is characterized by comprising the following steps of: the method is completed by the following steps:
(1) Firstly, a secondary circuit of a 10KV bus is connected to a voltage wiring terminal block, a power supply and 485 communication terminal or related wiring of a network interface to be perfect, a power switch is placed in an ON state, a voltage transformer opening triangle circuit disconnection monitoring device is powered ON to normally operate, and an operation indicator lamp is normally ON after hardware initialization is finished;
(2) Vector Ua vector, ub vector and Uc vector sum 3U during normal system operation 0 Zero, i.e. U L Vector sum U LN Vector equipotential, then measuring Ua phase and U phase respectively L The voltage between the phases is the voltage of the secondary winding of the phase A; measuring the voltage between Ub and Uc phases, ub and U L The voltages among the phases are the voltages of the secondary single-phase windings of the corresponding mutual inductors;
(3) Judging the wire breakage position: when any one phase voltage is equal to U L When the reference voltage Ux between phases is less than or equal to 40V, the open triangular loop U is judged L A broken line appears on one side of the phase, a broken line indicator lamp is lightened, and an alarm indicator lamp is also lightened; when any one phase voltage is equal to U L When the pressure difference Ux between phases is less than or equal to 40V, judging that the pressure difference is in the open triangular secondary circuit U L Phase to U LN A broken line happens between the phase grounding points, a broken line indicator lamp is lightened, and an alarm indicator lamp is also lightened; when any one phase voltage is equal to U LN When the voltage Ux between phases is less than or equal to 40V, judging that the open triangular loop U is formed LN A broken line happens in a loop behind the phase grounding point, a broken line indicator lamp is on, and an alarm indicator lamp is also on;
(4) Under the serial port communication mode, an operator sets a serial port number and a baud rate under a function menu through an operation key, after the communication connection is successful, a communication indicator lamp is turned on, the result of whether the open triangle loop is disconnected or not is judged, and a signal is sent to communication equipment of a dispatching master station through a communication unit;
(5) And after receiving accurate alarm information when the open triangular secondary circuit is broken, an maintainer immediately processes the information, so that hidden danger in the operation of the equipment can be eliminated.
The invention has the beneficial effects that: the open triangular loop disconnection monitoring device of the voltage transformer and the application method thereof can monitor and record three-phase voltage and zero sequence voltage in real time, can timely and accurately send out alarm information and report to a dispatching master station for processing by maintenance staff when disconnection occurs in an open triangular secondary loop, and eliminates hidden danger in equipment operation; the device is convenient to install and maintain, has a friendly human-computer interface, is flexible in communication mode, and ensures the reliability and the sensitivity of the monitoring result of the device and the defect-free operation of the open triangular loop through real-time monitoring of the voltage difference between the phase voltage and the open triangular loop and reliable hardware system design.
Drawings
Fig. 1 is a schematic view of the present invention in front view.
Fig. 2 is a schematic top view of a PCB motherboard of the present invention.
Fig. 3 is a schematic rear view of the structure of the present invention.
Fig. 4 is a schematic block diagram of the structural circuit of the present invention.
FIG. 5 is a schematic diagram illustrating a logic determination of a master control unit according to the present invention.
Fig. 6 is a schematic diagram of an auxiliary secondary winding loop of the structural voltage transformer of the present invention.
Detailed Description
Fig. 1, 2, 3, 4, 5, 6 illustrate one embodiment of the present invention.
This voltage transformer opening triangle return circuit broken string monitoring devices, including totally closed machine case 1 and the installation fixed ear 2 at both ends, be fixed in on cubical switchboard or the protection screen through installation fixed ear 2, its characterized in that: an initialization information liquid crystal display screen 3 is arranged on the front plate surface of the totally-enclosed case 1; an operation keyboard 4 is arranged on the lower side of the initialization information liquid crystal display screen 3; a signal indicator lamp 5 is arranged on the right side of the initialization information liquid crystal display screen 3; a PCB main board 6 provided with a communication unit 61, a main control unit 62, a voltage sensor data acquisition unit 63 and a power module 64 is arranged in the totally-enclosed case 1; the upper side of the rear wall of the totally-enclosed case 1 is provided with a secondary circuit voltage wiring terminal block 7 of a 10KV bus; a 485 communication terminal strip 8 is arranged on the lower side of the rear wall of the totally-enclosed case 1; the right side of the rear wall of the totally-enclosed case 1 is provided with an Ethernet interface 9; the voltage sensor data acquisition unit 63, the power supply module 64 and the operation keyboard 4 are connected to the main control unit 62, and the main control unit 62 is connected to the initialization information liquid crystal display 3 and the communication unit 61; the communication unit 61 sends the data to the communication device 65 through the serial port or the ethernet interface 9; u of secondary circuit voltage wiring terminal strip 7 of 10KV bus is gathered to voltage sensor data acquisition board 63 L Phase, U LN The voltage data of the phases Ua, ub, uc and Un are input into the main control unit 62 after the voltage transformer alternating A, B, C three-phase voltage and the open triangle voltage are subjected to second-order low-pass filtering, the voltage data is input into the main control unit 62, the main control unit 62 formed by a high-performance Blackfin series processor and a memory carries out processing logic judgment on the digital signals, and the main control unit 62 carries out judgment on the digital signalsThe current bus voltage and the information results of various parameters are displayed through the initialization information liquid crystal display 3, and signals are sent to the communication equipment 65 of the dispatching master station through the communication unit 61.
The invention is also implemented by the following measures: the operation keyboard 4 comprises a return key, a down key, an up key and a determination key, and has different functions under different menu environments, and is mainly used for parameter setting, menu switching and user interactive operation information.
The power module 64 is connected to a 220V ac/dc power supply.
The four signal indicating lamps 5 are respectively an operation indicating lamp 51, a disconnection indicating lamp 52, an alarm indicating lamp 53 and a communication indicating lamp 54, and are all connected with a circuit of the main control unit 62.
The application method of the open triangular loop disconnection monitoring device of the voltage transformer is characterized by comprising the following steps of: the method is completed by the following steps:
(1) Firstly, a secondary circuit of a 10KV bus is connected into a voltage wiring terminal block 7, a power supply and 485 communication terminal 8 or related wiring of a network interface 9 to be perfect, a power supply switch is placed in an ON state, a voltage transformer opening triangle circuit disconnection monitoring device is powered ON to normally operate, and an operation indicator lamp 51 is normally ON after hardware initialization is finished;
(2) Vector Ua vector, ub vector and Uc vector sum 3U during normal system operation 0 Zero, i.e. U L Vector sum U LN Vector equipotential, then measuring Ua phase and U phase respectively L The voltage between the phases is the voltage of the secondary winding of the phase A; measuring the voltage between Ub and Uc phases, ub and U L The voltages among the phases are the voltages of the secondary single-phase windings of the corresponding mutual inductors;
(3) Judging the wire breakage position: when any one phase voltage is equal to U L When the reference voltage Ux between phases is less than or equal to 40V, the open triangular loop U is judged L A broken line appears on one side of the phase, the broken line indicator lamp 52 is on, and the alarm indicator lamp 53 is also on; when any one phase voltage is equal to U L When the pressure difference Ux between phases is less than or equal to 40V, judging that the pressure difference is in the open triangular secondary circuit U L Phase to U LN Between opposite side contact pointsA broken wire is generated, a broken wire indication 52 is lighted, and an alarm indication lamp 53 is also lighted; when any one phase voltage is equal to U LN When the voltage Ux between phases is less than or equal to 40V, judging that the open triangular loop U is formed LN A broken line occurs in the loop after the phase grounding point, the broken line indicator 52 is lighted, and the alarm indicator 53 is also lighted;
(4) In the serial communication mode, an operator sets a serial number and a baud rate under a function menu by operating a key 4, after the communication connection is successful, a communication indicator lamp 54 is on, and a result of judging whether the open triangle loop is disconnected or not is sent to a communication device 65 of the dispatching master station by a communication unit 61;
(5) And after receiving accurate alarm information when the open triangular secondary circuit is broken, an maintainer immediately processes the information, so that hidden danger in the operation of the equipment can be eliminated.
Claims (1)
1. The application method of the voltage transformer open triangular loop disconnection monitoring device comprises a totally-enclosed case (1) and mounting fixing lugs (2) at two ends, and is characterized in that: an initialization information liquid crystal display screen (3) is arranged on the front plate surface of the totally-enclosed case (1); an operation keyboard (4) is arranged at the lower side of the initialization information liquid crystal display screen (3); a signal indicator lamp (5) is arranged on the right side of the initialization information liquid crystal display screen (3); a PCB main board (6) provided with a communication unit (61), a main control unit (62), a voltage sensor data acquisition unit (63) and a power module (64) is arranged in the totally-enclosed case (1); the upper side of the rear wall of the totally-enclosed case (1) is provided with a secondary circuit voltage wiring terminal strip (7) of a 10KV bus; a 485 communication terminal row (8) is arranged at the lower side of the rear wall of the totally-enclosed case (1); an Ethernet interface (9) is arranged on the right side of the rear wall of the totally-enclosed case (1); the voltage sensor data acquisition unit (63), the power module (64) and the operation keyboard (4) are connected to the main control unit (62), and the main control unit (62) is connected to the initialization information liquid crystal display screen (3) and the communication unit (61); the communication unit (61) sends the data to the communication equipment (65) through the serial port or the Ethernet interface (9); a voltage sensor data acquisition unit (63) acquires a secondary circuit voltage wiring terminal block (7) of a 10KV busU L Phase, U LN The voltage data of the phases, ua phase, ub phase, uc phase and Un phase are subjected to voltage transformer alternating A, B, C three-phase voltage and open triangular voltage, and then enter a voltage transformer data acquisition unit (63) to be converted into digital signals, the digital signals are input into a main control unit (62), the main control unit (62) formed by a high-performance Blackfin series processor and a memory carries out processing logic judgment on the digital signals, the main control unit (62) then displays the judged current bus voltage and various parameter information results through an initialization information liquid crystal display screen (3), and the signals are sent to a communication device (65) of a dispatching master station through a communication unit (61); the power supply module (64) is connected with a 220V alternating current/direct current power supply; the four signal indicating lamps (5) are respectively an operation indicating lamp (51), a disconnection indicating lamp (52), an alarm indicating lamp (53) and a communication indicating lamp (54), and are all connected with a circuit of the main control unit (62); the method is characterized in that: the method is completed by the following steps:
(1) Firstly, connecting a secondary circuit of a 10KV bus into a voltage wiring terminal block (7), a power supply and 485 communication terminal (8) or related wiring of a network interface (9) to be perfect, placing a power switch in an ON state, powering ON a voltage transformer open triangle circuit disconnection monitoring device to normally operate, and operating an indicator lamp (51) to be normally ON after hardware initialization is finished;
(2) Vector Ua vector, ub vector and Uc vector sum 3U during normal system operation 0 Zero, i.e. U L Vector sum U LN Vector equipotential, then measuring Ua phase and U phase respectively L The voltage between the phases is the voltage of the secondary winding of the phase A; measuring the voltage between Ub and Uc phases, ub and U L The voltages among the phases are the voltages of the secondary single-phase windings of the corresponding mutual inductors;
(3) Judging the wire breakage position: when any one phase voltage is equal to U L When the reference voltage Ux between phases is less than or equal to 40V, the open triangular loop U is judged L A broken line appears on one side of the phase, a broken line indicator lamp (52) is lightened, and an alarm indicator lamp (53) is also lightened; when any one phase voltage is equal to U L When the pressure difference Ux between phases is less than or equal to 40V, judging that the pressure difference is in the open triangular secondary circuit U L Phase to U LN Broken wire occurs between the phase-side grounding points, and broken wire refers toThe indicator (52) is lighted, and the alarm indicator (53) is also lighted; when any one phase voltage is equal to U LN When the voltage Ux between phases is less than or equal to 40V, judging that the open triangular loop U is formed LN A broken line happens in a loop behind the phase grounding point, a broken line indication lamp (52) is lightened, and an alarm indication lamp (53) is also lightened;
(4) Under the serial communication mode, an operator sets serial numbers and baud rates under the function menu through an operation key (4), after communication connection is successful, a communication indicator lamp (54) is on, and a result of whether the open triangle loop is disconnected or not is judged and a signal is sent to a communication device (65) of the dispatching master station through a communication unit (61).
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109255453A (en) * | 2018-11-20 | 2019-01-22 | 国网辽宁省电力有限公司葫芦岛供电公司 | A kind of marketing equipment operation tracking device |
| CN110658377B (en) * | 2019-10-23 | 2021-11-09 | 国网山西省电力公司阳泉供电公司 | Voltage secondary opening triangular loop monitoring device |
| CN113030834B (en) * | 2021-04-19 | 2023-01-10 | 北京送变电有限公司 | Transformer secondary circuit line calibration device and method |
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