CN109950883B - Protection measurement and control device and protection measurement and control method for automatic switch of power distribution network - Google Patents

Abstract

The invention discloses a protection measurement and control device and a protection measurement and control method for a distribution network automation switch. In addition to a circuit parameter acquisition circuit, a switch input circuit, a communication interface, a control loop, a relay output circuit, a signal acquisition circuit connected to the circuit parameter acquisition circuit, a device power supply, and a controller respectively connected to each part of the circuit, the device also includes a summing circuit and a first display device connected to the summing circuit. The first end of the summing circuit is connected to a first relay for collecting a quick-break current connected to a protection current acquisition module in the circuit parameter acquisition circuit, and the second end is connected to a second relay for collecting an overcurrent connected to the protection current acquisition module. The summing circuit is used to sum the quick-break current and the overcurrent to obtain a current sum value, and the current sum value is displayed through the first display device, which helps on-site operation and maintenance personnel to determine the specific location of a feeder fault point.

Description

Protection and measurement control device and protection and measurement control method for distribution network automation switch

Technical Field

The present invention relates to the technical field of power distribution network, and in particular to a protection and measurement control device and a protection and measurement control method for an automatic switch of a power distribution network.

Background Art

With the continuous development of distribution network automation technology and the increasing requirements of users for power supply reliability, the construction and operation of distribution network automation is particularly important, laying the foundation for fault isolation and rapid restoration of power supply to non-fault areas.

Among them, feeder automation is an important part of distribution network automation. To realize feeder automation, a reasonable distribution network structure is required, with the conditions of ring network power supply; the operating mechanism of each ring network switch, load switch and switch in the street distribution station must have a remote operation function; the ring network switch cabinet must have a reliable power supply for the switch operating device and a working device power supply for the protection measurement and control device (FTU) and communication equipment; and a reliable communication system that is not affected by the external environment.

Under normal conditions, feeder automation monitors the status of feeder section switches and tie switches, feeder current and voltage in real time, and realizes remote or local closing and opening of line switches. In the event of a fault, it obtains fault records, automatically identifies and isolates the faulty section of the feeder, and quickly restores power to non-faulty areas. Fault location, isolation, and automatic restoration are of great significance to improving power supply reliability and shortening power outage time in non-faulty areas.

Feeder fault location, isolation and automatic power restoration are unique functions of feeder automation. The system composed of circuit breakers and sectionalizers can automatically locate the fault when a permanent fault occurs in the feeder, and achieve fault isolation through the sequential action of the switching equipment; load transfer and power restoration are achieved in the distribution network with ring network operation or ring network structure but open loop operation. In the event of a transient fault, the fault usually disappears automatically after the fault current is cut off, and the circuit breaker can automatically reclose to restore power to the load.

It can be seen that an important type of device in the feeder automation of the distribution network is the automatic switch installed in the switch cabinet between substations. However, in actual applications, the automatic switch itself may have faults such as switch refusal to operate and communication failure, resulting in failure to remove or isolate the feeder fault point, making it impossible for operation and maintenance personnel to intuitively determine the specific location of the feeder fault point, resulting in complicated testing and maintenance work, and is not conducive to the rapid repair of distribution network faults.

How to enable operation and maintenance personnel to more conveniently determine the specific location of the feeder fault point, reduce the work pressure of the operation and maintenance personnel, and speed up the repair of distribution network faults is a technical problem that technical personnel in this field need to solve.

Summary of the invention

The purpose of the present invention is to provide a protection and measurement control device and a protection and measurement control method for a distribution network automation switch, which are used to enable operation and maintenance personnel to more conveniently determine the specific location of a feeder fault point, reduce the work pressure of the operation and maintenance personnel, and speed up the repair of distribution network faults.

In order to solve the above technical problems, the present invention provides a protection and measurement control device for a power distribution network automation switch, comprising a circuit parameter acquisition circuit, a switch input circuit, a communication interface, a control circuit, a relay output circuit, a signal acquisition circuit connected to the circuit parameter acquisition circuit, a device power supply, and a controller respectively connected to the circuit parameter acquisition circuit, the switch input circuit, the communication interface, the control circuit, the relay output circuit, the signal acquisition circuit and the device power supply, the controller is used to control the control circuit and the relay output circuit to perform a protection action according to the circuit parameters collected by the circuit parameter acquisition circuit and the switch signal input by the switch input circuit, and also includes:

A summing circuit having a first end connected to a first relay for collecting quick-break current connected to a protection current collection module in the circuit parameter collection circuit, and a second end connected to a second relay for collecting overcurrent connected to the protection current collection module, for summing the quick-break current and the overcurrent to obtain a current sum value;

A first display device connected to the summing circuit is used to display the current sum value.

Optionally, the first display device is specifically a touch screen.

Optionally, it further includes a first indicator light circuit connected to the summing circuit;

Wherein, the indicator light in the first indicator light circuit lights up when the current sum value is greater than a preset value.

Optionally, it further comprises a first signal light sign, a second signal light sign and a third signal light sign connected to the controller;

The controller controls the first signal light sign to light up when the corresponding automation switch fails to remove a fault, controls the second signal light sign to light up when the automation switch fails to isolate a fault, and controls the third signal light sign to light up when a communication abnormality occurs in the automation switch.

Optionally, it further includes a second indicator light circuit, a third indicator light circuit and a fourth indicator light circuit connected to the controller;

The controller controls the indicator light in the second indicator light circuit to light up when the corresponding automation switch fails to remove a fault, controls the indicator light in the third indicator light circuit to light up when the automation switch fails to isolate a fault, and controls the indicator light in the fourth indicator light circuit to light up when a communication abnormality occurs in the automation switch.

Optionally, a second display device connected to the controller for displaying status information of the automation switch is also included.

Optionally, a wireless communicator connected to the controller is also included.

Optionally, the wireless communicator is specifically a Wi-Fi communicator.

Optionally, the wireless communicator is specifically a GPRS communicator.

In order to solve the above technical problems, the present invention further provides a protection and measurement control method for a distribution network automation switch, based on the protection and measurement control device for a distribution network automation switch described in any one of the above, comprising:

The current sum value obtained by the summing circuit is saved as an event record SOE and uploaded to the specified address.

The protection and measurement and control device for distribution network automation switches provided by the present invention includes, in addition to a circuit parameter acquisition circuit, a switch input circuit, a communication interface, a control loop, a relay output circuit, a signal acquisition circuit connected to the circuit parameter acquisition circuit, a device power supply, and a controller respectively connected to the circuit parameter acquisition circuit, the switch input circuit, the communication interface, the control loop, the relay output circuit, the signal acquisition circuit and the device power supply, a summing circuit and a first display device connected to the summing circuit, wherein the first end of the summing circuit is connected to a first relay for collecting quick-break current connected to a protection current acquisition module in the circuit parameter acquisition circuit, and the second end is connected to a second relay for collecting overcurrent connected to the protection current acquisition module, and is used to sum the quick-break current and the overcurrent to obtain a current sum value, and the first display device is used to display the current sum value. By summing the quick-break current and the overcurrent, the current passing through the automatic switch can be obtained. When the current sum reaches a certain threshold, it is the fault current. Whether the fault current flows through the automatic switch is an important basis for on-site maintenance personnel to determine the specific location of the feeder fault point. Therefore, compared with the prior art, the protection measurement and control device provided by the present invention can enable maintenance personnel to more conveniently determine the specific location of the feeder fault point, reduce the work pressure of maintenance personnel, and speed up the repair of distribution network faults. The present invention also provides a protection measurement and control method for a distribution network automatic switch, which has the above-mentioned beneficial effects and is not repeated here.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic structural diagram of a protection and measurement and control device for a distribution network automation switch provided by an embodiment of the present invention;

FIG2 is a schematic diagram of a control panel of a protection measurement and control device provided by an embodiment of the present invention;

FIG3 is a schematic diagram of another control panel of a protection measurement and control device provided by an embodiment of the present invention;

FIG4 is a schematic diagram of a fault removal logic provided by an embodiment of the present invention;

FIG5 is a schematic diagram of a fault isolation logic provided by an embodiment of the present invention;

FIG6 is a schematic diagram of a "2-1" single ring network wiring mode provided by an embodiment of the present invention;

FIG. 7( a ) is a schematic diagram of a first automation switch failure scenario provided by an embodiment of the present invention;

FIG. 7( b ) is a schematic diagram of a second automation switch failure scenario provided by an embodiment of the present invention;

FIG7( c ) is a schematic diagram of a third automation switch failure scenario provided by an embodiment of the present invention;

FIG7( d ) is a schematic diagram of a fourth automation switch failure scenario provided by an embodiment of the present invention;

FIG7( e ) is a schematic diagram of a fifth automation switch failure scenario provided by an embodiment of the present invention;

FIG8( a ) is a schematic diagram showing a first automatic switch failure scenario according to an embodiment of the present invention;

FIG8( b ) is a schematic diagram showing a second automatic switch failure scenario according to an embodiment of the present invention;

FIG8( c ) is a schematic diagram showing a third automatic switch failure scenario according to an embodiment of the present invention;

FIG8( d ) is a schematic diagram showing a fourth automatic switch failure scenario according to an embodiment of the present invention;

FIG8( e ) is a schematic diagram showing a fifth automatic switch failure scenario provided by an embodiment of the present invention.

DETAILED DESCRIPTION

The core of the present invention is to provide a protection and measurement control device and a protection and measurement control method for distribution network automation switches, which are used to enable operation and maintenance personnel to more conveniently determine the specific location of the feeder fault point, reduce the work pressure of the operation and maintenance personnel, and speed up the repair of distribution network faults.

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Figure 1 is a schematic diagram of the structure of a protection and measurement and control device for a distribution network automation switch provided in an embodiment of the present invention; Figure 2 is a schematic diagram of a control panel of a protection and measurement and control device provided in an embodiment of the present invention; Figure 3 is a schematic diagram of another control panel of a protection and measurement and control device provided in an embodiment of the present invention.

As shown in FIG1 , the protection and measurement and control device for the distribution network automation switch provided by the embodiment of the present invention includes a circuit parameter acquisition circuit, a switch input circuit, a communication interface, a control loop, a relay output circuit, a signal acquisition circuit connected to the circuit parameter acquisition circuit, a device power supply, and a controller respectively connected to the circuit parameter acquisition circuit, the switch input circuit, the communication interface, the control loop, the relay output circuit, the signal acquisition circuit and the device power supply. The controller is used to control the relay output circuit to perform a protection action based on the control loop according to the circuit parameters collected by the circuit parameter acquisition circuit and the switch signal input by the switch input circuit, and also includes:

A summing circuit having a first end connected to a first relay SJ for collecting quick-break current connected to a protection current collection module in a circuit parameter collection circuit, and a second end connected to a second relay TJ for collecting overcurrent connected to the protection current collection module, for summing the quick-break current and the overcurrent to obtain a current sum value;

The first display device L1 connected to the summing circuit is used to display the current sum value.

In a specific implementation, the circuit parameter acquisition circuit includes a bus voltage acquisition module connected to the bus voltages YMc, YMb, and YMc, a measurement current acquisition module, a protection current acquisition module, and a zero-sequence current acquisition module connected to the three-phase lines, wherein the quick-break overcurrent device is connected to the protection current acquisition circuit, one end output of the quick-break overcurrent device is connected to the first relay SJ, and the other end output is connected to the second relay TJ, and the second relay TJ is also controlled by a remote trip signal.

The switching quantity input circuit includes remote control signal terminals, spring energy storage signal terminals, trolley working terminals, trolley test terminals, remote signal terminals 5 to 12, remote signal common terminals, etc., and the remote control signal terminals, spring energy storage signal terminals, trolley working terminals, trolley test terminals, remote signal terminals 5 to 12 are all connected to the positive pole of the 24V device power supply, and the remote signal common terminal is connected to the negative pole of the 24V device power supply.

The communication interface may adopt RS485 communication interface.

The control circuit includes the control device power supply (+, -) terminals, trip input terminals, trip output terminals, closing input terminals, anti-trip push-out terminals, closing output terminals, trip position monitoring terminals, and closing position monitoring terminals. The relay output circuit includes trip output terminals, closing output terminals, and logic trip terminals.

Among them, the positive and negative poles of the control device power supply are respectively connected to the device power supply terminals +KM and -KM, and the tripping input terminal, the tripping output terminal, and the two ends of the tripping output terminal of the relay output circuit are all connected to the switch TQ. At the same time, the circuit of the tripping input terminal also includes a manual tripping switch to control the tripping action; the closing input terminal, the closing output terminal, and the two ends of the closing terminal of the relay output circuit are all connected to the switch HQ. At the same time, the circuit of the closing input terminal also includes a manual closing switch to control the closing action.

The signal acquisition circuit includes an accident signal (SJ) acquisition circuit, a warning signal (YJ) acquisition circuit, a device fault (GZJ) acquisition circuit, a reset input (+, -) circuit, etc. The accident signal (SJ) acquisition circuit, the warning signal (YJ) acquisition circuit, and the device fault (GZJ) acquisition circuit are also connected to a circuit including a signal power supply, a single-phase electric energy meter (DD), and a high-voltage circuit breaker (DL), as shown in Figure 1.

The connection of the device power supply is shown in Figure 1.

On the basis of the above device, the protection measurement and control device provided in the embodiment of the present invention further includes a summing circuit and a first display device L1 , and the specific connection is as mentioned above and FIG. 1 .

The first display device L1 may be a touch screen, on which the words “fault current I≥” may be displayed.

When the current sum is greater than a preset value, it is considered that a fault current has flowed through the automatic switch where the protection and measurement and control device is located. In order to more intuitively remind the operation and maintenance personnel of the occurrence of the fault current, the protection and measurement and control device provided in the embodiment of the present invention may further include a first indicator light circuit connected to the summing circuit;

Wherein, the indicator light in the first indicator light circuit lights up when the current sum value is greater than a preset value.

The panel effect of the protection and measurement and control device provided by the embodiment of the present invention is schematically shown in Figure 2. In addition to the nameplate, the display window for displaying the A-phase current, the B-phase current, and the C-phase current, the voltage and current type selection knob, the condensation controller, the lighting switch, the energy storage indicator light, the open position indicator light, the closed position indicator light, the signal source selection knob (OK), the opening and closing selection knob (1SA), the protection tripping output pressure plate (LP1), the protection closing output pressure plate (LP2), the remote control opening output pressure plate (LP3), the remote control closing output pressure plate (LP4), the reclosing function input pressure plate (LP5), and the synchronization function input pressure plate (LP6), it also includes a first display device L1, which can display words such as "fault current I ≥ 828A".

Among them, indicator lights with different functions are set in different colors, such as the energy storage indicator light is set to yellow, the position indicator light is set to green, and the closed position indicator light is set to red; pressure plates with different functions are set in different colors, such as the outlet pressure plate is red, and the functional pressure plate is yellow; for the connecting piece screw-tightening pressure plate, the open end should be installed on the top.

Furthermore, each switch and knob should be equipped with a plastic cover to prevent accidental touching.

The panel effect of the protection measurement and control device with the first indicator light circuit added is shown in FIG3 , and the fault current indicator light can be arranged side by side with other indicator lights.

The protection measurement and control unit provided in the embodiment of the present invention is fixed on the secondary chamber cabinet door by embedded installation, and is connected to the integrated measurement and control communication unit via Ethernet or RS485 bus. Correspondingly, 2 or more RJ45 network interfaces should be reserved in the integrated measurement and control communication unit.

The message requirements of the protection measurement and control device provided in the embodiment of the present invention include:

Event sequence records should be classified into equipment failure sequence records and automation equipment failure sequence records;

The intelligent distributed signals received by the protection and measurement and control device shall be saved as SOE records, such as the signal of the adjacent switch detecting the fault current, the fault removal signal sent by the adjacent switch, the fault isolation signal sent by the adjacent switch, the refusal to operate signal sent by the adjacent switch, the communication fault signal of the switch, etc.;

Jitter signals should be filtered in event sequence recording.

The protection and measurement and control device for distribution network automation switches provided in an embodiment of the present invention includes, in addition to a circuit parameter acquisition circuit, a switch input circuit, a communication interface, a control loop, a relay output circuit, a signal acquisition circuit connected to the circuit parameter acquisition circuit, a device power supply, and a controller respectively connected to the circuit parameter acquisition circuit, the switch input circuit, the communication interface, the control loop, the relay output circuit, the signal acquisition circuit and the device power supply, a summing circuit and a first display device connected to the summing circuit, wherein the first end of the summing circuit is connected to a first relay for collecting quick-break current connected to a protection current acquisition module in the circuit parameter acquisition circuit, and the second end is connected to a second relay for collecting overcurrent connected to the protection current acquisition module, and is used to sum the quick-break current and the overcurrent to obtain a current sum value, and the first display device is used to display the current sum value. By summing the quick-break current and the overcurrent, the current passing through the automatic switch can be obtained. When the current sum reaches a certain threshold, it is the fault current. Whether the fault current flows through the automatic switch is an important basis for on-site operation and maintenance personnel to determine the specific location of the feeder fault point. Therefore, compared with the prior art, the protection measurement and control device provided by the present invention enables the operation and maintenance personnel to more conveniently determine the specific location of the feeder fault point, reduces the work pressure of the operation and maintenance personnel, and speeds up the repair of distribution network faults.

Based on the above embodiment, in another embodiment, when the automation switch itself has problems such as fault removal failure, fault isolation failure, communication failure, etc., if it can be displayed on site, it will be more helpful for on-site operation and maintenance personnel to locate the feeder fault point.

Therefore, preferably, the protection and measurement and control device for the power distribution network automation switch further includes a first signal light sign, a second signal light sign and a third signal light sign connected to the controller;

The controller controls the first signal light sign to light up when the corresponding automation switch fails to remove a fault, controls the second signal light sign to light up when the automation switch fails to isolate a fault, and controls the third signal light sign to light up when a communication abnormality occurs in the automation switch.

Alternatively, the protection and measurement and control device for a power distribution network automation switch may include a second indicator light circuit, a third indicator light circuit, and a fourth indicator light circuit connected to the controller;

The controller controls the indicator light in the second indicator light circuit to light up when the corresponding automation switch fails to remove a fault, controls the indicator light in the third indicator light circuit to light up when the automation switch fails to isolate a fault, and controls the indicator light in the fourth indicator light circuit to light up when a communication abnormality occurs in the automation switch.

In specific implementation, conditions such as "fault removal failure", "fault isolation failure" or "communication abnormality" can be judged by the controller itself. By adding a selection circuit and a drive circuit between the controller and the signal light sign or indicator light circuit, the indicator lights in the corresponding signal light sign or indicator light circuit can be controlled to light up, thereby clearly notifying the on-site operation and maintenance personnel of the fault condition of each automatic switch. The on-site operation and maintenance personnel can clearly locate the feeder fault point based on this.

In addition, conditions such as "fault removal failure", "fault isolation failure" or "communication abnormality" can also be displayed through the display device. Therefore, the protection and measurement and control device for the distribution network automation switch can also include a second display device connected to the controller for displaying the status information of the automation switch.

Furthermore, in order to save communication lines, the protection and measurement and control device for the distribution network automation switch may also include a wireless communicator connected to the controller. In a specific implementation, the wireless communicator may be a Wi-Fi communicator or a GPRS communicator.

FIG. 4 is a schematic diagram of a fault removal logic provided by an embodiment of the present invention; FIG. 5 is a schematic diagram of a fault isolation logic provided by an embodiment of the present invention.

The following is an explanation of the logic of fault removal or fault isolation by the automatic switch.

When a fault occurs on the main line, the 10kV outgoing line switch of the substation will remove the fault. The automatic switch protection measurement and control unit on the main line detects the fault of this unit, and exchanges fault information with the left and right intelligent distributed units to determine the fault section. After detecting that there is no pressure and no current, the switch opens to remove and isolate the fault.

As shown in Figure 4, the automatic switch detects a fault and starts logic judgment (the recommended logic judgment time is 2s). If the automatic switch itself fails and one of the two sides has no fault signal, the fault point is located on its rear side. If other exit conditions in the figure are met within the logic judgment time, a trip command can be issued; wait for Tdz4 time (100ms is the switch action time), if there is no refusal to move, set the fault removal flag.

As shown in Figure 5, if the automatic switch itself has no faults, but only one of the two sides has a fault current, locate the fault on the front side and start the logic judgment (the logic judgment time is recommended to be 2s); when the switch itself changes from pressure to no pressure within the logic judgment time and closes, a trip command can be issued; wait for Tdz4 time (100ms is the switch action time), if there is no refusal to move, set the "fault isolation successful" flag.

Figure 6 is a schematic diagram of a "2-1" single-ring network wiring mode provided in an embodiment of the present invention; Figure 7(a) is a schematic diagram of a first automation switch fault scenario provided in an embodiment of the present invention; Figure 7(b) is a schematic diagram of a second automation switch fault scenario provided in an embodiment of the present invention; Figure 7(c) is a schematic diagram of a third automation switch fault scenario provided in an embodiment of the present invention; Figure 7(d) is a schematic diagram of a fourth automation switch fault scenario provided in an embodiment of the present invention; Figure 7(e) is a schematic diagram of a fifth automation switch fault scenario provided in an embodiment of the present invention; Figure 8(a) is a schematic diagram of a first automation switch fault scenario display provided in an embodiment of the present invention; Figure 8(b) is a schematic diagram of a second automation switch fault scenario display provided in an embodiment of the present invention; Figure 8(c) is a schematic diagram of a third automation switch fault scenario display provided in an embodiment of the present invention; Figure 8(d) is a schematic diagram of a fourth automation switch fault scenario display provided in an embodiment of the present invention; Figure 8(e) is a schematic diagram of a fifth automation switch fault scenario display provided in an embodiment of the present invention.

The following describes how to locate the feeder fault point:

As shown in Figure 6, taking the "2-1" single ring network wiring mode as an example, L1 and L2 are the main supply lines, CB1 and CB2 switches are the outgoing line switches of the substation, and the #1-#3 ring network cabinets of L1 and L2, and the incoming and outgoing line switches of the #4 ring network cabinet are equipped with circuit breakers with line PTs. Each ring network cabinet is equipped with automatic switches (K1, K2, K3, K4, K5, K6, K7, K8, K21, K22, K23, K24, K25, K26). The 603 switch represents the branch switch and is equipped with a circuit breaker without a line PT. Any section switch on the main line may be used as a tie switch.

Scene 1

Assuming that the feeder fault point is between K4 and K5, K4 should have cleared the fault and K5 should have isolated the fault. However, due to the refusal of K3, K4, K5, and K6 to operate, K2 operated to clear the fault and K7 operated to isolate the fault. The consequences of the operation are shown in Figure 7(a). The dispatcher cannot determine the location of the actual fault point, which makes it more troublesome for the dispatcher and on-site operation and maintenance personnel to handle the fault, and increases the probability of no operation.

Scene 2

Assuming that the fault point is still between K4 and K5, K4 should have cleared the fault and K5 should have isolated the fault.

In terms of fault removal, due to the communication failure of K3 and K4, after CB1 tripped, K3 and K4 switches detected abnormal communication, loss of pressure, and the switch was in the closed position, and the fault current flowed, so they tripped and removed the fault. K2 detected abnormal communication and loss of pressure of the adjacent switch, and the switch was in the closed position, and detected the fault current and tripped. There was fault current on both sides of K1, so it did not operate. At this point, the fault power outage range expanded to K2;

In terms of fault isolation, K5 detected abnormal communication and loss of pressure in the adjacent switch, and the switch itself was in the closed position, but no fault current was detected, so it did not act and failed to send a fault isolation success signal. K5 failed to isolate the fault;

In terms of power transfer, the contact switch K8 lost pressure on one side. Due to communication failure, it did not receive the power transfer mark and power transfer demand after successful isolation within the delay time, so it did not act and the power transfer failed. The non-fault areas from K5 to K8 could not restore power supply in time.

The specific consequences of the action are shown in Figure 7(b), which makes it impossible for the dispatcher to determine the actual location of the fault point, which adds trouble to the fault handling of the dispatcher and on-site operation and maintenance personnel, and increases the probability of no operation.

Scene 3

Assuming the fault point is still between K4 and K5, K4 should remove the fault and K5 should isolate the fault;

In terms of fault removal, due to K3 communication failure, K4 refused to operate. After CB1 tripped, K4 detected the fault and refused to operate, and sent a refusal signal. However, K3 communication was abnormal, pressure was lost, the switch was in the closed position, and there was a fault current flowing through it, so it tripped and removed the fault. K2 detected that the adjacent switch had abnormal communication, pressure was lost, and the switch was in the closed position. It detected the fault current and tripped. There was a fault current on both sides of K1, so it did not operate. At this point, the fault power outage range expanded to K2.

In terms of fault isolation, K5 meets the conditions of single-side fault, loss of pressure, and closing of its own switch. K5 opens, isolates the fault, and sends an isolation success signal.

The power supply is transferred. The contact switch K8 loses pressure on one side. The transfer sign and transfer demand after successful isolation are received within the delay time. The switch is closed and the power transfer is successful.

The specific consequences of the action are shown in Figure 7(c), which can easily cause the dispatcher to misjudge the location of the feeder fault point.

Scene 4

Assuming the fault point is between K2 and K3, it should be removed by K3 to isolate the fault;

In terms of fault removal, due to K2 communication failure, the communication between K1 and K2 switches is abnormal, the voltage is lost, the switch is in the closed position, and the fault current flows, so it trips, removes the fault, and sends a communication abnormality and protection action signal; at this point, the fault power outage range is expanded to K1;

In terms of fault isolation, K3 does not act but sends a communication abnormality signal;

In terms of power transfer, the contact switch K8 lost pressure on one side, but did not receive the power transfer sign and power transfer demand after successful isolation within the delay time, and the power transfer failed;

The specific consequences of the action are shown in Figure 7(d), which can easily cause the dispatcher to misjudge the location of the feeder fault point.

Scene 5

Assuming the fault point is still between K2 and K3, the fault should be removed and K3 should isolate the fault;

In terms of fault removal, since K2 refuses to operate, K1 receives a refusal to operate flag, loses pressure, the switch is in the closed position, and there is a fault current flowing, so it trips, removes the fault, and sends a protection action signal; at this point, the fault power outage range is expanded to K1;

In terms of fault isolation, K3 communication is abnormal, it does not operate, and sends a communication abnormality signal;

In terms of power transfer, the contact switch K8 lost pressure on one side, but did not receive the power transfer sign and power transfer demand after successful isolation within the delay time, and the power transfer failed;

The specific consequences of the action are shown in Figure 7(e), which can easily cause the dispatcher to misjudge the location of the feeder fault point.

After adding a signal light sign or indicator light or a second display device, for scenes one to five, the information that the on-site operation and maintenance personnel can obtain is shown in Figure 8(a) to Figure 8(e), which can clearly determine the fault conditions of each automatic switch, and the dispatcher and on-site operation and maintenance personnel can intuitively determine the location of the feeder fault point based on this. In addition to displaying conditions such as "fault removal failure", "fault isolation failure" or "communication abnormality", other conditions such as "fault removal (successful)", "fault isolation (successful)" and "refusal to operate" can also be displayed.

The above describes in detail the various embodiments corresponding to the protection and measurement control device for distribution network automation switches. On this basis, the present invention also discloses a protection and measurement control method for distribution network automation switches based on the above device.

The protection, measurement and control method for a distribution network automation switch provided in an embodiment of the present invention is based on the protection, measurement and control device for a distribution network automation switch described in any one of the above embodiments, and includes:

The current sum value obtained by the summing circuit is saved as an event record SOE and uploaded to the specified address.

Furthermore, the protection measurement and control method for distribution network automation switch may also include:

The fault removal status signal and the fault isolation status signal are sent to the protection and control devices of the master station and the tie switch.

On the display screen of the master station, the display as shown in FIG8(a) to FIG8(e) can be performed, so that the fault point is clear at a glance.

The above is a detailed introduction to a protection and measurement control device and a protection and measurement control method for a distribution network automation switch provided by the present invention. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims (7)

1. The utility model provides a protection measurement and control device for distribution network automation switch, includes circuit parameter acquisition circuit, switching value input circuit, communication interface, control circuit, relay output circuit, with circuit parameter acquisition circuit connection's signal acquisition circuit, the device power, and respectively with circuit parameter acquisition circuit, switching value input circuit, communication interface, control circuit, relay output circuit signal acquisition circuit with the controller that the device power is connected, the controller is used for according to circuit parameter that circuit parameter acquisition circuit gathered and switching value signal control that switching value input circuit input control circuit with relay output circuit carries out the protection action, wherein, circuit parameter acquisition circuit includes the busbar voltage collection module that is connected with busbar voltage YMc, YMb, YMc, the measuring current collection module that is connected with the three phase line, protection current collection module, zero sequence current collection module, the quick-break overcurrent device that is connected with protection current collection circuit, quick-break overcurrent device's one end output is connected first relay, another end output connection second relay, its characterized in that still includes:

The first end is connected with the first relay which is connected with the protection current acquisition module in the circuit parameter acquisition circuit and is used for acquiring quick-break current, and the second end is connected with the second relay which is connected with the protection current acquisition module and is used for acquiring overcurrent, and the summation circuit is used for summing the quick-break current and the overcurrent to obtain a current sum value;

A first display device connected to the summing circuit for displaying the current sum;

the first indicator light circuit is connected with the summing circuit;

The indicator lamp in the first indicator lamp circuit is turned on when the current sum value is larger than a preset value;

The device also comprises a first signal light word board, a second signal light word board and a third signal light word board which are connected with the controller;

the controller controls the first signal light character plate to be lightened when the corresponding automatic switch fails to cut off faults, controls the second signal light character plate to be lightened when the automatic switch fails to cut off faults, and controls the third signal light character plate to be lightened when the automatic switch is abnormal in communication;

The controller is connected with the first indicator light circuit and the second indicator light circuit;

The controller controls the indication lamp in the second indication lamp circuit to be turned on when the corresponding automatic switch fails in fault removal, controls the indication lamp in the third indication lamp circuit to be turned on when the automatic switch fails in fault isolation, and controls the indication lamp in the fourth indication lamp circuit to be turned on when the automatic switch is abnormal in communication.

2. The protection and measurement and control device according to claim 1, wherein the first display device is specifically a touch screen.

3. The protection measurement and control device of claim 1, further comprising a second display device connected to the controller for displaying status information of the automated switch.

4. The protection measurement and control device of claim 1, further comprising a wireless communicator coupled to the controller.

5. The protection measurement and control device of claim 4, wherein the wireless communicator is embodied as a Wi-Fi communicator.

6. The protection and measurement and control device according to claim 4, wherein the wireless communicator is a GPRS communicator.

7. A protection and measurement and control method for an automatic switch of a power distribution network, characterized in that the protection and measurement and control device for an automatic switch of a power distribution network according to any one of claims 1 to 6 comprises:

And saving the current sum value obtained by summation of the summation circuit as an event record SOE and uploading the event record SOE to a specified address.