Control circuit for preventing misoperation of switching-on power transmission of multi-dimensional power system

Abstract

The invention belongs to the technical field of switching-on power transmission of a power system, and relates to a control circuit for preventing misoperation of switching-on power transmission of a multi-dimensional power system. The control circuit comprises a relay protection power supply monitoring circuit and a locking control circuit; the relay protection power supply monitoring circuit comprises a first resistor, a first fusing resistor and a first relay which are installed in series. The two ends of the relay protection power supply monitoring circuit are connected to the positive electrode and the negative electrode of a first direct-current power supply respectively. The locking control circuit comprises a locking closing state operation indicating circuit, an original circuit breaker closing control circuit, a second relay and an outgoing circuit breaker closing loop; and the original circuit breaker closing control circuit is connected in series with the second relay, and then the circuit, the locking closing state operation indicating circuit and the outgoing circuit breaker closing loop are connected in parallel. According to the invention, power transmission misoperation accidents that a line is provided with a ground wire, the side or the opposite side of the line is provided with a ground knife or a relay protection device is not switched on and switched off during switching-on operation of a power system can be avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of power system closing and power-on, and particularly relates to a control circuit for preventing misoperation of multi-dimensional power system closing and power-on. Background Art

[0002] The current "five-prevention" equipment for preventing misoperation in the power industry and in operation for many years is limited to the procedures of operating disconnecting switches, switches, etc. of primary equipment units in substations, and does not consider forgetting to switch on the locking circuit of the circuit breaker by the protection device. That is, it does not consider that when the protection device is not put into operation, then in the event of a fault, the circuit breaker will not receive the correct tripping instruction, or serious consequences may occur, including equipment damage, personal injury, and even large-scale power outages. The role of the protection device is to quickly detect and take measures when a fault occurs in the power system, such as tripping the circuit breaker to isolate the fault area and prevent the accident from expanding. Moreover, in the existing power system, there are often cases where the line does not have or activate the due protection device during operation; or before power-on, the relevant protection device is not activated or put into operation, and power is directly supplied to a loop that has been connected with a grounding wire. This may cause the fault current to not be detected and quickly cut off and isolated in time, thereby causing the upstream circuit breaker or the substation incoming line circuit breaker to trip, resulting in power outages in a larger area.

[0003] During the power system closing and power transmission process, the following defects still exist: the opening of the grounding knife at the opposite end of the transmission line cannot be seen at both ends of the transmission line. At one end of the transmission line, the operator cannot directly observe whether the grounding knife at the other end is opened; there is no ground knife opposite end locking closing device at both ends, and there is a lack of a device that can lock each other between the two ends of the transmission line. This locking device is used to ensure that the circuit breaker or switch at the other end cannot be closed when the grounding knife at one end is not opened; there is no conventional grounding wire to lock the opposite end and the local end to close the switch, and there is no locking device, so that when the grounding wire is not completely removed, the locking device can prevent the opposite end (the other end) and the local end (the same end) from closing. The circuit breaker or switch is closed to prevent short circuit or other dangerous situations caused by misoperation; the transmission line is not equipped with an intelligent grounding wire to prevent the closing and power transmission locking circuit, and the transmission line is not equipped with a grounding wire with monitoring and communication functions, so it is impossible to monitor the grounding wire status in real time and transmit information to the switching operation control system; in addition, the transmission line is generally not equipped with an electrical locking circuit, which is used to prevent the circuit breaker or switch from closing and powering when the grounding wire is not completely removed. The locking circuit can control the circuit breaker or switch through electrical signals to ensure that the circuit breaker will not be closed and power will not be transmitted when the grounding wire exists. Therefore, conventional transmission lines cannot ensure that the circuit breaker will not be closed and power will not be transmitted when the grounding wire exists. In the above various situations, the operator blindly follows the dispatching instructions to close the circuit breaker and transmit power without confirming whether the grounding wire has been removed. This operation will cause the entire substation to lose power supply and cause serious safety accidents. Therefore, whether it is possible to provide a control circuit that can ensure that the power system switching operation does not occur by mistake, and does not cause misoperation accidents such as power supply with a grounding switch, a grounding switch at the other end of the line, a grounding wire on the line, relay protection not being put into operation, or relay protection tripping pressure plate not being put into operation is a technical problem that needs to be urgently solved in the present invention. Summary of the invention

[0004] In view of this, the present invention provides a control circuit for preventing misoperation of closing and power transmission in a multi-dimensional power system.

[0005] In order to solve the above technical problems, the technical solution adopted by the control circuit for preventing misoperation of closing and power transmission in a multi-dimensional power system of the present invention includes: A multi-dimensional power system closing and power transmission anti-misoperation control circuit, the control circuit controls the power system closing and power transmission operation by connecting multiple locking circuits in parallel; the control circuit includes a relay protection power supply monitoring circuit and a locking control circuit; The relay protection power supply monitoring circuit comprises a first resistor, a first fuse resistor and a first relay which are installed in series, two ends of the relay protection power supply monitoring circuit are respectively connected to the positive electrode and the negative electrode of the first DC power supply, and the relay protection power supply monitoring circuit is connected to the original relay protection device and the first DC power supply switch; The locking control circuit includes a locking closing state operation indication circuit, an original circuit breaker closing control circuit, a second relay and an outgoing circuit breaker closing circuit; the closing control circuit is connected in series with the second relay, and the original circuit breaker closing control circuit is connected in series with the second relay, and the locking closing state operation indication circuit and the outgoing circuit breaker closing circuit are connected in parallel, and the two ends of the locking control circuit after the parallel connection are respectively connected to the two ends of the second DC power supply, and the locking control circuit is connected in series with a second DC power supply switch.

[0006] Furthermore, the locked closing state operation indication circuit includes a third resistor and a second fuse resistor installed in series, and a first state indicator light is also installed on the locked closing state operation indication circuit, and a fourth resistor is connected in parallel at both ends of the first state indicator light.

[0007] Furthermore, a normally closed contact of a closing lockout relay is installed in series on the closing circuit of the outgoing circuit breaker.

[0008] Furthermore, the closing control circuit includes a first branch, a second branch, a third branch, a fourth branch and a fifth branch arranged in parallel.

[0009] Furthermore, a first relay normally closed contact is provided on the first branch; and a magnetically controlled switch linked to a relay protection tripping outlet pressure plate is provided on the second branch.

[0010] Furthermore, the first branch, the second branch, the third branch, the fourth branch and the fifth branch are respectively provided with second status indicator lights, and the second status indicator lights are respectively provided with fifth resistors in parallel.

[0011] Furthermore, the third branch, the fourth branch and the fifth branch are respectively connected to the opposite-end grounding knife switch locking and closing, the opposite-end grounding wire AI image recognition locking and closing, and the line intelligent grounding wire locking and closing.

[0012] Furthermore, the first relay is a monitoring relay for monitoring whether the relay protection is powered on and is used for the relay protection power supply, and the second relay is a closing locking relay.

[0013] The beneficial effects of the present invention are: A dual indication system is set up. Among the multiple status indicator lights, the first status indicator light is a red light emitting diode, which is used to show that the locking circuit has been powered on and activated, and the second status indicator light is a green light emitting diode, which is used to show the category of not allowing closing or locking.

[0014] A relay protection power supply monitoring circuit is set up. After obtaining electrical energy from the positive and negative poles of the DC power supply of the original relay protection device, it can establish a loop for monitoring the operating state of the protection device. This relay protection power supply monitoring circuit starts working immediately after the protection device is powered on, thus ensuring that the protection device is in a normal operating state.

[0015] In addition, the first branch, the second branch, the third branch, the fourth branch, and the fifth branch are connected in parallel to ensure the simplest multi-dimensional anti-misoperation interlocking, so as to improve the reliability and safety of the system. This design can ensure that when the outgoing line of the power system is closed and powered on, it realizes the transformation from full-personnel prevention to technical prevention in all aspects. Through the five-fold criteria of "protection not powered on interlock + protection pressure plate not inserted interlock + grounding knife state interlock + AI image recognition interlock + intelligent grounding wire interlock", a logical AND gate relationship is formed. If any condition is not met, the closing is locked. With multiple interlocks for guarantee, the safety is improved. Brief Description of the Drawings

[0016] Figure 1 It is a wiring schematic diagram of the present invention (the circuit described in this application is within the dotted line box, and the equipment outside the box is the access equipment).

[0017] Reference Signs in the Drawings: 1: Relay protection power supply monitoring circuit, 2: First resistor, 3: First fuse resistor, 4: First relay, 5: First DC power supply, 6: Relay protection device, 7: First DC power supply switch, 8: Closing interlock state operation indication circuit, 9: Closing control circuit, 10: Second relay, 11: Outgoing line circuit breaker closing loop, 12: Interlock control circuit, 13: Second DC power supply, 14: Second DC power supply switch, 15: Third resistor, 16: Second fuse resistor, 17: First status indicator light, 18: Fourth resistor, 19: Normally closed contact of closing interlock relay, 20: First branch, 21: Second branch, 22: Third branch, 23: Fourth branch, 24: Fifth branch; 25: Normally closed contact of first relay, 26: Magneto switch, 27: Second status indicator light, 28: Fifth resistor, 29: Closing interlock of opposite-end grounding knife, 30: Closing interlock of AI image recognition of opposite-end grounding wire, 31: Closing interlock of line intelligent grounding wire. Detailed Embodiments

[0018] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined purpose, the following will describe in detail the specific embodiments, structures, features, and their effects of the present invention in combination with the accompanying drawings and preferred embodiments.

[0019] It should be noted that the terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such terms can be interchanged under appropriate circumstances.

[0020] It should be noted that in this application, unless otherwise specified, the orientation terms such as "upper, lower, top, bottom" are usually in reference to the direction shown in the drawings, or in reference to the vertical, perpendicular or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner, outer" refer to the inner and outer of the contour of each component itself, but the above orientation terms are not used to limit the present invention.

[0021] Embodiment As Figure 1 shown, this embodiment discloses a control circuit for preventing misoperation of closing and energizing a multi-dimensional power system. The control circuit controls the closing and energizing operation of the power system by paralleling a plurality of locking circuits.

[0022] The control circuit includes a relay protection power supply monitoring circuit 1 and a locking control circuit 12. The relay protection power supply monitoring circuit is used to monitor whether the original power supply of the relay protection is powered on; the locking control circuit is used to parallelly connect the normally closed contacts of the power-off locking relay of the relay protection power supply, the pressure plate linkage magnetic control lock, the closing lock of the opposite-end earthing switch 29, the closing lock of the opposite-end grounding wire AI image recognition 30, and the closing lock of the line intelligent grounding wire 31, so as to respectively monitor whether the relay protection power supply is powered on, whether the protection pressure plate is inserted, whether the opposite-end grounding wire is closed, whether the opposite-end grounding wire is correctly installed, and whether the line intelligent grounding wire is removed.

[0023] The relay protection power supply monitoring circuit 1 includes a first resistor 2, a first fuse resistor 3 and a first relay 4 connected in series. The two ends of the relay protection power supply monitoring circuit 1 are respectively connected to the positive and negative poles of a first DC power supply 5, and the relay protection power supply monitoring circuit 1 is connected to the original relay protection device 6 and the first DC power supply switch 7. The first DC power supply is the original power supply of the relay protection device, and the relay protection device and the first DC power supply switch are also existing devices on the original power supply side of the relay protection device.

[0024] The relay protection power supply monitoring circuit 1 is used to monitor in real time whether the original power supply of the relay protection is powered on. When the relay protection device 6 detects that the first DC power supply is put into operation, the relay protection device is in a normal working state, and at the same time, it immediately triggers the first relay 4 to act. The normally closed contact 25 of the first relay 4 disconnects, cutting off the relay protection power supply monitoring circuit 1 and not sending a locking signal to the locking control circuit 12. On the contrary, when the first relay monitors that the original power supply of the relay protection is not powered on, the normally closed contact 25 of the first relay conducts, the first shunt conducts, and the closing of the locked circuit breaker is started. The first fuse resistor 3 provides overcurrent protection to ensure the safety of the relay protection power supply monitoring circuit 1 itself without affecting the operation of the first DC power supply 5. In addition, the relay protection power supply monitoring circuit 1 also monitors the starting circuit for closing the locked circuit breaker when not powered on, that is, to ensure that there is no misoperation of closing when the original power supply of the relay protection is not powered on, thus protecting the safety of the circuit and equipment.

[0025] The locking control circuit 12 includes a locking closing state operation indication circuit 8, an original circuit breaker closing control circuit 9, a second relay 10, and an outgoing line circuit breaker closing loop 11. The original circuit breaker closing control circuit 9 is connected in series with the second relay 10. The circuit after the original circuit breaker closing control circuit 9 and the second relay 10 are connected in series, the locking closing state operation indication circuit 8, and the outgoing line circuit breaker closing loop 11 are connected in parallel. The two ends of the locked control circuit 12 after parallel connection are respectively connected to the two ends of the second DC power supply 13, and a second DC power supply switch 14 is connected in series on the locking control circuit 12. The second DC power supply is the operating power supply for the closing loop of the original circuit breaker.

[0026] The locking closing state operation indication circuit 8 includes a third resistor 15 and a second fuse resistor 16 connected in series. A first status indicator light 17 is also installed on the locking closing state operation indication circuit 8, and a fourth resistor 18 is connected in parallel at both ends of the first status indicator light 17.

[0027] A normally closed contact 19 of the closing locking relay is connected in series on the outgoing line circuit breaker closing loop 11.

[0028] The closing control circuit 9 includes a first shunt 20, a second shunt 21, a third shunt 22, a fourth shunt 23, and a fifth shunt 24 arranged in parallel.

[0029] The first shunt 20 is provided with a normally closed contact 25 of the first relay; the second shunt 21 is provided with a magnetically controlled switch 26 linked with the original circuit relay protection tripping outlet pressure plate, where the original circuit relay protection tripping outlet pressure plate is the protection pressure plate mentioned above.

[0030] Second status indicators 27 are respectively arranged on the first shunt 20, the second shunt 21, the third shunt 22, the fourth shunt 23 and the fifth shunt 24, and fifth resistors 28 are respectively connected in parallel on the second status indicators 27.

[0031] On the third shunt 22, the fourth shunt 23 and the fifth shunt 24, a closing interlock of the opposite - end grounding switch 29, an AI image recognition closing interlock of the opposite - end grounding wire 30, and a closing interlock of the line intelligent grounding wire 31 are respectively connected.

[0032] The first relay 4 is a monitoring relay for monitoring whether the relay protection is powered on, and the second relay 10 is a closing interlock relay.

[0033] In this application, the first DC power supply is used to represent the power supply of the relay protection device to ensure its continuous monitoring and protection of the power system; the second DC power supply is used for the closing operation of the circuit breaker. When the normal closing circuit of the circuit breaker is in operation, it can ensure that the circuit breaker can be quickly closed when needed.

[0034] The core function of the interlock control circuit 12 is to implement a "one - in - five" interlock logic through five parallel shunts, and any interlock condition trigger prohibits closing. The interlock control circuit 12 includes three key modules: a closing control circuit 9, a closing status indicator, and an execution unit. Among them, the closing status indicator, that is, the power - on operation status indicator of the closing interlock loop, refers to the first status indicator and the second status indicator mentioned above; the execution unit includes the second relay. The closing control circuit 9 includes five shunts, corresponding respectively to the interlock due to the relay protection not being powered on, the linkage magneto - control of the pressure plate, the grounding switch interlock, the AI recognition, and the intelligent grounding wire interlock. The power - on operation status indicator of the closing interlock loop is to display a red light through the first status indicator 17 to confirm its closing - allowed / interlocked state, and the fourth resistor 18 is connected in parallel to achieve current shunting. The execution unit controls the on - off of the closing loop through the second relay 10, and forms an interlock by connecting in series the normally - closed contact 19 of the closing interlock relay.

[0035] The first shunt 20 is the normally - closed contact of the relay for interlocking when the relay protection is not powered on. The normally - closed contact of the first relay is connected on the first shunt. The trigger condition is that the relay protection is not powered on. When the original power supply of the relay protection is not powered on, the normally - closed contact of the first relay closes, the first shunt conducts, and the second status indicator on the first shunt lights green.

[0036] The second branch 21 is a pressure plate linkage magnetic control interlock, which means that it is attached to the existing protection pressure plate on the original circuit through a magnetic induction, thus forming a linkage with the pressure plate. When the protection pressure plate is disconnected or not in operation, the interlock is triggered. A Hall sensor (±1mm detection accuracy) can be used to detect the position state of the protection pressure plate. In this embodiment, when the Hall sensor detects that the position state of the pressure plate exceeds 3mm, the pressure plate linkage magnetic control interlock mechanism is triggered. If the relay protection export pressure plate is disconnected and not in operation at this time, the magnetic control switch closes, the second branch 21 conducts, and the coil of the second relay 10 is energized; its normally closed contact is disconnected, and the closing circuit is disconnected, prohibiting the closing operation.

[0037] The third branch 22 is a grounding knife interlock. The triggering condition is that the opposite grounding knife is in the closed state. The technical implementation method is to transmit the auxiliary contact signal through the GOOSE message. The interlock process includes: the third branch 22 conducts; the coil of the second relay 10 is energized and its normally closed contact is disconnected; the closing circuit is disconnected. Among them, the second status indicator 27 lights up green.

[0038] The fourth branch 23 is connected to the AI image recognition interlock. The triggering condition is the presence of the grounding wire. In this application, the technical implementation method can adopt the YOLOv5 model (2 million pixels / 30fps). In this branch, the AI recognition process includes: the industrial camera captures the grounding wire image → the YOLOv5 model runs on the Jetson Nano platform → the recognition accuracy rate ≥ 99.5%. After the grounding wire is recognized, the interlock signal is output to the fourth branch 23 through Modbus TCP.

[0039] The fifth branch 24 is the intelligent grounding wire state detection channel in the interlock logic. This access channel mainly triggers the interlock signal and forcibly cuts off the closing circuit to prevent closing with the grounding wire when the intelligent grounding wire is not correctly removed or is in a non-safe position.

[0040] Generally, intelligent grounding wires are usually equipped with sensors that can detect the state of the grounding wire in real time, including whether it is connected and the firmness of the connection. The data of the sensors is transmitted to the central control system through the communication network. The central controller receives, processes, and analyzes the data transmitted by the sensors. When the central control system detects that the grounding wire is not correctly removed or is in a non-safe position, it triggers the interlock signal and forcibly cuts off the closing circuit to prevent closing with the grounding wire.

[0041] In this embodiment, the metal end of the intelligent grounding wire device can also be physically connected to the grounding wire, and its "connected" state can be confirmed through the NFC chip. Additionally, an opto-isolator can be connected in the fifth shunt in this embodiment. When using this method, the workflow includes: when the grounding wire is connected, the NFC reader installed on the grounding knife of the grounding pile actively polls the surrounding tags; the NFC tag of the intelligent grounding wire returns an encrypted position code; the system verifies the validity of the code, and the method for verifying the validity of the code includes verifying the match with the preset device ID + position code; if the verification passes and a mechanical connection is detected, it is determined that the "ground wire is in place". At this time, the locking action process of the fifth shunt includes: signal triggering, the NFC reader continuously sends a locking signal to the fifth shunt 24; the fifth shunt conducts, the opto-isolator connected in the fifth shunt starts, and then the second relay is started; the closing circuit is disconnected, and the closing locking indicator light is lit.

[0042] In this application, the "AND gate + OR gate" combined logic is mainly used, and it is judged whether the condition meets the locking condition by whether the coil of the second relay 10 is energized; when any locking shunt is triggered (such as the third shunt 22 conducting due to the closing of the grounding knife), the coil of the second relay 10 is energized, the closing circuit is disconnected, and it is locked. In this application, the indicator lights set in the first shunt, the second shunt, the third shunt, the fourth shunt, and the fifth shunt respectively display the reasons for the locking of the circuit breaker closing, which is convenient for finding the reasons affecting the closing.

[0043] The above is only a preferred embodiment of the present invention, and it does not impose any form of limitation on the present invention. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments with equivalent changes within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the protection of the technical solution of the present invention.

Claims

1. A multi-dimensional power system closing and power transmission anti-misoperation control circuit, characterized in that: The control circuit controls the closing and power transmission operation of the power system by connecting multiple locking circuits in parallel; the control circuit includes a relay protection power supply monitoring circuit and a locking control circuit; The relay protection power supply monitoring circuit comprises a first resistor, a first fuse resistor and a first relay which are installed in series, two ends of the relay protection power supply monitoring circuit are respectively connected to the positive electrode and the negative electrode of the first DC power supply, and the relay protection power supply monitoring circuit is connected to the original relay protection device and the first DC power supply switch; The locking control circuit includes a locking closing state operation indication circuit, an original circuit breaker closing control circuit, a second relay and an outgoing circuit breaker closing circuit; the closing control circuit is connected in series with the second relay, and the original circuit breaker closing control circuit is connected in series with the second relay, and the locking closing state operation indication circuit and the outgoing circuit breaker closing circuit are connected in parallel, and the two ends of the locking control circuit after the parallel connection are respectively connected to the two ends of the second DC power supply, and the locking control circuit is connected in series with a second DC power supply switch.

2. A multi-dimensional power system closing and power transmission anti-misoperation control circuit according to claim 1, characterized in that: The closing state indication circuit comprises a third resistor and a second fuse resistor installed in series, and a first state indicator light is also installed on the locking closing state operation indication circuit, and a fourth resistor is connected in parallel at both ends of the first state indicator light.

3. A multi-dimensional power system closing and power transmission anti-misoperation control circuit according to claim 1, characterized in that: A normally closed contact of a closing lockout relay is installed in series on the closing circuit of the outgoing line circuit breaker.

4. A multi-dimensional power system closing and power transmission anti-misoperation control circuit according to claim 3, characterized in that: The closing control circuit comprises a first branch, a second branch, a third branch, a fourth branch and a fifth branch which are arranged in parallel.

5. A multi-dimensional power system closing and power transmission anti-misoperation control circuit according to claim 4, characterized in that: The first branch is provided with a first relay normally closed contact; the second branch is provided with a magnetically controlled switch linked to the relay protection tripping outlet pressure plate.

6. A multi-dimensional power system closing and power transmission anti-misoperation control circuit according to claim 5, characterized in that: The first branch, the second branch, the third branch, the fourth branch and the fifth branch are respectively provided with second status indicator lights, and the second status indicator lights are respectively provided with fifth resistors in parallel.

7. A multi-dimensional power system closing and power transmission anti-misoperation control circuit according to claim 6, characterized in that: The third branch, the fourth branch and the fifth branch are respectively connected with the opposite-end grounding knife switch locking and closing, the opposite-end grounding wire AI image recognition locking and closing, and the line intelligent grounding wire locking and closing.

8. A multi-dimensional power system closing and power transmission anti-misoperation control circuit according to claim 7, characterized in that: The first relay is a monitoring relay for monitoring whether the relay protection is powered on, and the second relay is a closing locking relay.

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