CN211351706U - Automatic tracking compensation arc extinction and small current route selection complete equipment - Google Patents
Automatic tracking compensation arc extinction and small current route selection complete equipment Download PDFInfo
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- CN211351706U CN211351706U CN201922363335.0U CN201922363335U CN211351706U CN 211351706 U CN211351706 U CN 211351706U CN 201922363335 U CN201922363335 U CN 201922363335U CN 211351706 U CN211351706 U CN 211351706U
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- arc extinction
- route selection
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- automatic tracking
- compensation arc
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Abstract
The utility model discloses automatic trail compensation arc extinction and undercurrent route selection integrated equipment belongs to power equipment control field, concretely relates to automatic trail compensation arc extinction and undercurrent route selection integrated equipment, including the integrated equipment body, the integrated equipment body includes grounding transformer, adjustable reactor, damping resistance and other auxiliary assembly that connect according to the power supply principle, and its special character lies in: the automatic control and operation system of the programmable controller and the computer monitoring system are used for controlling the complete device body. The earthing transformer selected by the complete set of computer on-line monitoring type automatic tracking compensation arc-extinguishing and small current route-selecting equipment is a special equipment, and it adopts zigzag structure and adopts three-phase asymmetric method to produce a fixed zero-sequence voltage. The grounding transformer is more economical, reliable and less in loss in design than other grounding transformers.
Description
Technical Field
The utility model belongs to power equipment control field, concretely relates to automatic trail compensation arc extinction and undercurrent route selection integrated equipment and application thereof.
Background
The original shift arc suppression coil is manually adjusted and can only be adjusted under the condition of quitting. When the system is in single-phase grounding, the size and phase relationship between the zero sequence voltage of the grounding bus and each outgoing line zero sequence current on the bus, and the size and phase relationship between all outgoing line zero sequence currents on the grounding bus are difficult to know, or the known numerical values are inaccurate, and the grounding line is difficult to select by utilizing various line selection schemes with relative principles, double criteria and equal population ratio. And the original gear shifting arc suppression coil can only operate in an overcompensation state. Therefore, the complete device for automatic tracking compensation arc extinction and small current route selection has necessity and significance.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide an automatic trail compensation arc extinction and undercurrent route selection integrated equipment and application thereof, it can utilize relative principle, dual criterion, colony to compare the multiple route selection scheme optimization combination that equals and select the ground connection circuit, has realized automatic accurate control, has also solved original shift arc suppression coil and can only be in the technical problem of operation under the compensation state.
The technical solution of the utility model is that:
the utility model provides an automatic trail compensation arc extinction and undercurrent route selection integrated equipment, includes the integrated equipment body, the integrated equipment body includes grounding transformer, adjustable reactor, damping resistance and other auxiliary assembly who connect according to the power supply principle, and its special character lies in: the automatic control and operation system of the programmable controller and the computer monitoring system are used for controlling the complete device body.
The automatic control and operation system of the programmable controller comprises a signal acquisition interface, a programmable controller, an operation execution loop and a protection loop which are connected with each other; and the programmable controller automatic control and operation system automatically controls the complete device body when the computer monitoring system exits.
The computer monitoring system monitors and remotely controls the complete device body by utilizing the serial communication of the computer and the programmable controller.
The complete device body is divided into a dry device and an oil immersed device, wherein the dry device is formed by respectively installing all grounding transformers, adjustable reactors and mutual inductor coils which are epoxy cast dry coils; the oil immersed device is oil-insulated by a grounding transformer and an adjustable reactor, and the grounding transformer and the adjustable reactor can be arranged in the same oil tank.
The grounding transformer structure is in Z-shaped connection, and three phases are asymmetric; the grounding transformer can be provided with a secondary coil to provide a power supply for three-phase four-wire.
The adjustable reactor selects various types of iron core adjusting air gap type, load switch type, capacitance adjusting type or direct current bias type according to the needs of users.
The damping resistor is a chip wire-wound resistor or a stainless steel resistor; the long-term running current is 5% -10% of the rated current of the reactor, and overcurrent and overvoltage protection is adopted, so that the damping resistor can be in short circuit timely when a single-phase earth fault occurs in the power grid.
The application of the complete device for automatically tracking and compensating arc extinction and small current route selection is characterized in that: the method is mainly used for a single bus subsection single set of device, and the mode mainly means that a power grid is a single bus subsection two main transformers or one main transformer, one main transformer runs for a long time, the other main transformer is standby, and a second section of bus runs in parallel for a long time; in this way, only one set of computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete equipment is needed to be installed.
The application of the complete device for automatically tracking and compensating arc extinction and small current route selection is characterized in that: the method is mainly characterized in that the power grid is a single bus section two main transformers or a double bus bypass two main transformers which operate for a long time, and the two main transformers operate in two sections in a row; in this way, a computer online monitoring type automatic tracking compensation arc extinction and small current line selection complete device is respectively arranged in the two sections, and when the two sections operate in a row, the two devices respectively realize automatic tracking compensation on the single-phase grounding capacitance current on the bus of the section; when the two sections of buses run in parallel, the two sets of devices run in parallel; at the moment, the two sets of devices can simultaneously compensate the single-phase grounding capacitance current on the two sections of buses, the current is evenly distributed in two sets, and the error is below 5A.
The application of the complete device for automatically tracking and compensating arc extinction and small current route selection is characterized in that: the method is mainly characterized in that three main transformers of three buses run two main transformers at ordinary times, one main transformer is standby, or three main transformers run in a row; in this way, a set of computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete equipment is respectively installed on three sections of buses, and according to the operation condition of a power grid, when three main transformers operate three sections of buses to separately operate, the three sets of equipment respectively realize automatic tracking compensation on single-phase grounding capacitance current on the bus; when two main transformers run, wherein two sections of buses run in parallel, only two devices are put into operation, and one device is reserved; when the single-phase grounding capacitance current of the parallel buses exceeds the single set of compensation current, one set of standby is put into parallel operation with the previous set.
The utility model has the advantages that:
1. the earthing transformer selected by the complete set of computer on-line monitoring type automatic tracking compensation arc-extinguishing and small current route-selecting equipment is a special equipment, and it adopts zigzag structure and adopts three-phase asymmetric method to produce a fixed zero-sequence voltage. The grounding transformer is more economical, reliable and less in loss in design than other grounding transformers.
2. The selected adjustable reactor is an adjustable air gap type reactor. The adjustable air gap type reactor has the disadvantage of higher vibration and noise. Because the iron core moves up and down, vibration and noise generated by the air gap cannot be eliminated. The adjustable reactor iron core of the device is fixed by adopting the guide rail, and special treatment is carried out on the structure, so that the vibration and the noise of the reactor are effectively reduced.
The adjustable reactor selected by the computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete equipment can also be selected from other adjustable reactors. For example: and the on-load switch is a turn-adjusting type, a capacitance-adjusting type and a direct-current magnetic bias type reactor. The on-load switch turn-adjusting reactor adjusts the number of turns of a reactor coil by utilizing a tap of the on-load switch adjusting reactor coil, thereby achieving the purpose of adjusting the inductance of the reactor. Compared with an adjustable air gap type reactor, the on-load switch turn-adjusting type reactor has electric contact and step adjustment, but because the iron core of the on-load switch turn-adjusting type reactor is fixed, the vibration and the noise of the on-load switch turn-adjusting type reactor are easier to control than those of the adjustable air gap type reactor. The capacitance regulating type is that a group of capacitors are connected in parallel on a fixed reactor, and the total inductance is regulated by switching on different numbers of capacitors.
At present, adjustable reactors are mainly selected to be an adjustable air gap type and a switch type. They have individual characteristics.
3. The computer on-line monitoring type automatic tracking compensation arc extinction and small current route selection complete equipment adopts a small resistance grounding mode of an electric reactor string. The small resistor is also called a damping resistor, the resistance value is generally 10-20 omega, and the resistance value is generally related to the parameters of the power grid. The long-term stable current is generally 10-20% of the rated current of the reactor.
4. The computer on-line monitoring type automatic tracking compensation arc extinction and small current route selection complete device realizes the automatic tracking compensation of the single-phase earth fault capacitance current of the power grid. When the power grid normally operates, when the power grid parameters (mainly referring to the ground capacitance of the power grid after the circuit breaker is operated) are changed, the automatic control system can automatically adjust the inductance of the adjustable reactor in real time until a setting value (for example, the residual current is below 5A) is reached, when the power grid has a single-phase earth fault, the reactor is adjusted at the optimal position, and the earth residual current is controlled within the setting value range. The damping resistor is shorted at this time. When the single-phase earth-saving fault is relieved, the damping resistor is automatically switched in.
The automatic control system of the computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete device adopts a programmable controller and a large-screen dot matrix Liquid Crystal Display (LCD), is all Chinese, and has rich and visual display information. The line alarm output and the line tripping outlet are independent outlet modules. Self-checking function: the execution of the core hardware circuitry and software of the device is monitored over time. The automatic delivery function is as follows: no matter what operation interface the device is in after being electrified, if no operation is carried out for 1 minute, the device automatically enters the running state (except for the fault alarm of the device). The programmable controller replaces the original control panel or singlechip and relay system, and the computer on-line monitoring system realizes the monitoring and remote control of the complete equipment, so that the automatic control system of the complete equipment realizes digitization and intellectualization, and the automatic control system is simple, reliable and accurate. The transformer substation is suitable for being used by an unattended transformer substation.
Drawings
Fig. 1 is a structural diagram of a standard double-bus power grid using two sets of arc extinction and small current line selection complete equipment.
Fig. 2 is a schematic block diagram of the present invention.
Fig. 3 shows the timing communication process of the present invention.
Fig. 4 shows the communication flow of the utility model when no new event is found in the inquiry event.
Fig. 5 shows the communication flow of the new event in the event query of the present invention.
Fig. 6 is a schematic view of a terminal.
FIG. 7 is a schematic diagram of a computer-based on-line monitoring type automatic tracking compensation arc extinction and small current route selection complete device.
FIG. 8 is a schematic diagram of a complete set of computer-based online monitoring type automatic tracking compensation arc extinction and small current line selection equipment.
FIG. 9 is a schematic diagram of a complete set of devices for installing three sets of computers, namely an online monitoring type automatic tracking compensation arc extinction and small current line selection.
Detailed Description
First, control principle
The computer on-line monitoring type automatic tracking compensation arc-extinguishing and small current line-selecting complete equipment is a concept provided for original gear-shifting arc-extinguishing coil. The original shift arc suppression coil is manually adjusted and can only be adjusted under the condition of quitting. The computer on-line monitoring type automatic tracking compensation arc-extinguishing and small current line-selecting complete equipment is characterized by that when the power network is normally operated, it can real-timely monitor zero-sequence voltage of every section of bus of the system and zero-sequence current of every outgoing line, and when the system is single-phase grounded, said equipment can calculate and analyze the magnitude and phase relationship between zero-sequence voltage of grounded bus and zero-sequence current of every outgoing line on said bus and magnitude and phase relationship between zero-sequence currents of all outgoing lines on the grounded bus, and utilize various line-selecting schemes of relative principle, double criterion and group ratio, etc. to make optimum combination to select grounded line, display and memorize related information and give out alarm signal at the same time. The problem that the original gear shifting arc suppression coil can only operate in an overcompensation state is solved. Due to the adoption of advanced principle, advanced hardware and software technology, the line selection is accurate and reliable.
The computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete device utilizes a computer to realize man-machine conversation, so that the complete device is intelligent.
Computer on-line monitoring type automatic tracking compensation arc extinction and small current route selection complete equipment structure
As shown in the attached figure 1, the computer online monitoring type automatic tracking compensation arc extinction and small current line selection complete device comprises a complete device body, a programmable controller automatic control and operation system and a computer monitoring system. The computer monitoring system is a stand-alone system. The kit can work properly without a computer monitoring system. Two sets of devices installed in the same transformer substation can share one set of control system, and only the interface and the execution loop of the programmable controller are added. In the control process, different programs are adopted to respectively control the two sets of devices, and simultaneously, the two sets of devices can be controlled to run in parallel.
The computer on-line monitoring type automatic tracking compensation arc extinction and small current route selection complete device body comprises a grounding transformer, an adjustable reactor, a damping resistor and other auxiliary equipment. The grounding transformer adopts special equipment, the structure of the grounding transformer is Z-shaped connection, and the three phases are asymmetric. The method has the characteristic of small zero sequence impedance. The grounding transformer may have a secondary winding to provide power for three-phase four-wire applications.
The adjustable reactor in the computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete set can be selected from various types such as iron core air gap type, loaded switch type, capacitance type and direct current magnetic bias type. According to the needs of the user.
The automatic control and operation system of the programmable controller comprises a signal acquisition interface, the programmable controller, an operation execution loop and a protection loop. It can automatically control the complete equipment when the computer monitoring system is quitted.
The computer monitoring system utilizes the serial communication of a computer and a programmable controller to monitor and remotely control the complete equipment. It can be independent of the plant automatic control system.
The damping resistor is a failure-prone component of the plant. And attention is paid to type selection and design protection. The chip wire-wound resistor is generally selected, and a stainless steel resistor can also be used. The long-term running current is 5% -10% of the rated current of the reactor, and overcurrent and overvoltage protection is adopted, so that the damping resistor can be in short circuit timely when a single-phase earth fault occurs in the power grid.
The complete device body is divided into a dry type device and an oil immersed type device, wherein the dry type device is formed by separately installing all grounding transformers, adjustable reactors and mutual inductor coils which are epoxy cast dry type coils. The oil immersed device is oil-insulated by a grounding transformer and an adjustable reactor, and the grounding transformer and the adjustable reactor can be arranged in the same oil tank. The grounding transformer can be used for supplying power to a transformer substation.
Computer on-line monitoring type automatic tracking compensation and small current line selection arc extinction complete equipment communication center
1. Communication interface: the factory default setting is RS 485.
2. The specific contents of the default protocol of the device are as follows:
2.1, the upper computer sends a timing command: (CRT)
2.2, event query
2.21, the upper computer issues a fault information query command: (ASK)
2.2.2 lower computer response information
The messages that are answered without a new event are as follows: (ACK)
The returned messages when there is a new event are as follows: (R)
3. Communication flow:
timing: see fig. 3;
and (3) inquiring events: the communication flow chart is shown in figure 4 when no new event exists, and the communication flow chart is shown in figure 5 when a new event exists; note:
device address: 00H-99H.
A circuit: 01H-24H represent 1-24 lines, respectively. 00H denotes bus ground.
The time is the BCD code.
The communication mode is as follows: 8 bit data bit, 1 bit start bit, 1 bit stop bit, no check, asynchronous half duplex, baud rate 2400 bps.
4 terminal diagram
4.1 schematic terminal view, see fig. 6:
4.2 binding post arranges the table:
fourth, computer on-line monitoring type automatic tracking compensation and small current line selection arc extinction complete equipment application
Design selection
The design and model selection mainly comprises the selection of the number and the model of the device. The number of the devices is selected according to the number of the high-voltage buses of the transformer substation and a main variable, a complete device is generally installed for each section of bus, and only one device needs to be installed when the two sections of buses run in a long-term bus coupling mode. The other mothers are not usually installed.
Single bus section single set device
The mode mainly means that the power grid is a single-bus subsection two main transformers (or one main transformer), one main transformer runs for a long time, one standby main transformer runs for a long time, and two sections of buses run in parallel for a long time. In this way, only one set of computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete equipment is needed to be installed.
Two sets of devices for single bus section (or double bus bypass)
The mode mainly means that the power grid is a single-bus subsection two main transformers or a double-bus bypass long-term operation two main transformers, and two sections are operated in a split mode. In this way, a computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete device is respectively installed in the two sections, see the attached figure 7, and when the two sections operate in a row, the two devices respectively realize automatic tracking compensation on the single-phase grounding capacitance current on the bus of the section. When two sections of buses run in parallel, the two sets of devices run in parallel, and the two sets of devices are shown in the attached figure 8. At the moment, the two sets of devices can simultaneously compensate the single-phase grounding capacitance current on the two sections of buses, the current is evenly distributed in two sets, and the error is below 5A.
Three-section bus three-set device
The mode mainly means that three main transformers with three buses operate two main transformers at ordinary times, one main transformer is standby, or three main transformers operate in a split mode, and the mode is shown in an attached figure 9. In this way, a set of computer on-line monitoring type automatic tracking compensation arc extinction and small current line selection complete equipment is respectively installed on three sections of buses, and according to the operation condition of a power grid, when three main transformers operate three sections of buses to separately operate, the three sets of equipment respectively realize automatic tracking compensation on single-phase grounding capacitance current on the bus; when two main transformers run, wherein two sections of buses run in parallel, only two sets of devices are put into operation, and one set of devices is reserved. When the single-phase grounding capacitance current of the parallel buses exceeds the single set of compensation current, one set of standby is put into parallel operation with the previous set.
When the main bus of the transformer substation has more than three sections, economic operation needs to be considered during selection, and generally, only a long-term operation state is considered, and a special operation state is not considered.
The selection of the model mainly considers bus voltage, single-phase earth fault capacitance current and installation conditions. The bus voltage is 6kV, 10kV and 35 kV. Firstly, the single-phase earth fault capacitance current of each section of bus is estimated. The single-phase ground fault capacitance current is mainly determined by the type and length of the cable. When the single-phase earth fault capacitance current is calculated, the cable behind the transmission station at the lower end of the cable needs to be considered, and the single-phase earth fault capacitance current of the power grid bus can be estimated after the cable capacitance current is calculated.
The general calculation formula for the 6kV power grid is as follows: IC 1.14 × ICC +2.88+ IDC
In the formula, IC: for single-phase earth fault capacitor current of power grid bus
ICC: calculating capacitance current for cable
IDC: the power grid surge capacitor current.
The general calculation formula for the IC grid is: IC 1.2 × ICC +4.8+ IDC
And after the single-phase earth fault capacitance current of the power grid bus is calculated, selecting the model of the device according to the calculation result. The single-phase earth fault capacitance current is generally selected to be 50-70% of the rated current of the device, and a room for development is left for a newly-built transformer substation.
The compensation current ranges of the complete device are 5-25A, 10-50A, 20-75A, 30-100A and 50-150A respectively.
Claims (7)
1. The utility model provides an automatic trail compensation arc extinction and undercurrent route selection integrated equipment, includes the integrated equipment body, the integrated equipment body includes grounding transformer, adjustable reactor, damping resistance and the auxiliary assembly who connects according to the power supply principle, its characterized in that: the automatic control and operation system of the programmable controller and the computer monitoring system are used for controlling the complete device body.
2. The automatic tracking compensation arc extinction and small current route selection complete device according to claim 1, is characterized in that: the automatic control and operation system of the programmable controller comprises a signal acquisition interface, a programmable controller, an operation execution loop and a protection loop which are connected with each other; and the programmable controller automatic control and operation system automatically controls the complete device body when the computer monitoring system exits.
3. The automatic tracking compensation arc extinction and small current route selection complete device according to claim 1, is characterized in that: the computer monitoring system monitors and remotely controls the complete device body by utilizing the serial communication of a computer and a programmable controller.
4. The automatic tracking compensation arc extinction and small current route selection complete device according to any one of claims 1 to 3, is characterized in that: the complete device body is divided into a dry device and an oil immersed device, wherein the dry device is formed by respectively installing all grounding transformers, adjustable reactors and mutual inductor coils which are epoxy cast dry coils; the oil immersed device is oil-insulated by a grounding transformer and an adjustable reactor, and the grounding transformer and the adjustable reactor can be arranged in the same oil tank.
5. The automatic tracking compensation arc extinction and small current route selection complete device according to claim 4, is characterized in that: the grounding transformer structure is in Z-shaped connection, and three phases are asymmetric; the grounding transformer can be provided with a secondary coil to provide a power supply for three-phase four-wire.
6. The automatic tracking compensation arc extinction and small current route selection complete device according to claim 5, is characterized in that: the adjustable reactor is selected from an iron core adjusting air gap type, a load switch type, a capacitance adjusting type or a direct current magnetic bias type according to user requirements.
7. The automatic tracking compensation arc extinction and small current route selection complete device according to claim 6, is characterized in that: the damping resistor is a chip wire-wound resistor or a stainless steel resistor; the long-term running current is 5% -10% of the rated current of the reactor, and overcurrent and overvoltage protection is adopted, so that the damping resistor can be in short circuit timely when a single-phase earth fault occurs in the power grid.
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| CN201922363335.0U CN211351706U (en) | 2019-12-25 | 2019-12-25 | Automatic tracking compensation arc extinction and small current route selection complete equipment |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112909904A (en) * | 2021-03-03 | 2021-06-04 | 广东电网有限责任公司 | Resistance grounding system and control method thereof |
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2019
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112909904A (en) * | 2021-03-03 | 2021-06-04 | 广东电网有限责任公司 | Resistance grounding system and control method thereof |
| CN112909904B (en) * | 2021-03-03 | 2022-05-24 | 广东电网有限责任公司 | Resistance grounding system and control method thereof |
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