Monitoring circuit of tripping outlet loop of relay protection device

Abstract

The utility model provides a monitoring circuit of a tripping outlet loop of a relay protection device, relates to the field of relay protection of an electric power system, and solves the problems of real-time detection and early warning of hidden faults such as disconnection of the tripping outlet loop. The tripping outlet loop is composed of a protection device and a circuit breaker control cabinet which are connected with each other and form an electrical loop. Potential sensors are installed at the two ends of the protection device, the potential sensors are used for detecting potentials at the two ends of the protection device respectively, the potential sensors are connected with a potential monitoring unit, and the potential monitoring unit is connected to a monitoring system; a potential sensor RP1 is mounted on a wire between the positive electricity common end + KM and the positive electricity terminal CD; a potential sensor RP2 is mounted on a wire between the tripping outlet connecting piece CLP and the tripping outlet contact TJ: 2 terminal; according to the utility model, full-loop monitoring can be realized, disconnection faults of a tripping outlet loop of the protection device can be found in advance, and power failure range expansion caused by refusal of operation of a circuit breaker can be avoided.

Description

Technical Field

[0001] The utility model relates to the field of relay protection in power systems and is applied to relay protection devices, specifically to a monitoring circuit for the trip outlet circuit of relay protection devices. Background Art

[0002] As a core component of modern social infrastructure, the safe and stable operation of the power system is of crucial importance. In the power system, primary equipment such as generators, transformers, and lines undertakes the tasks of energy conversion and transmission, while relay protection devices play the role of guardians, responsible for monitoring the system status. Once an abnormality or fault is detected, the protection strategy is immediately activated, and the fault area is quickly isolated by controlling the operation of the circuit breaker to prevent the expansion of the accident and ensure the overall safety and reliability of the system.

[0003] Relay protection devices collect various electrical characteristic quantities in the power system, such as voltage, current, frequency, power, etc., and use preset logic algorithms for real-time analysis and judgment. Once it is found that the fault characteristics meet the preset protection criteria, the relay protection device will trigger the trip outlet circuit and send a trip command to the circuit breaker, causing the circuit breaker to operate and cut off the faulty part to achieve fault isolation.

[0004] As the last link for the relay protection device to implement the control function, the trip outlet circuit directly determines the effectiveness and timeliness of the protection action. It connects the output of the relay protection device and the trip mechanism of the circuit breaker and is the bridge for converting the protection strategy into a physical action. However, in the existing power system, the status monitoring of the trip outlet circuit has obvious deficiencies, lacking effective on-line monitoring means, which has become a weak link in the relay protection system.

[0005] In actual operation, the reliability of the trip outlet circuit is challenged by various factors. One of the most typical problems is the loosening of the positive power common terminal of the trip outlet circuit. This loosening phenomenon may cause the circuit to break. Even if the relay protection device detects a fault and triggers a trip command, it cannot effectively convey it to the circuit breaker, resulting in the circuit breaker being unable to operate in a timely manner, the fault not being isolated in a timely manner, and ultimately the accident range may be expanded, seriously threatening the safe operation of the power system. Summary of the Utility Model

[0006] Based on the current situation in the background art, the purpose of the utility model is to solve the problems of real-time detection and early warning of hidden faults such as circuit breakage in the trip outlet circuit, and thus a monitoring circuit for the trip outlet circuit of the relay protection device is proposed. The utility model can achieve full-circuit monitoring of the trip outlet circuit of the relay protection device, reduce the monitoring blind area, and the potential monitoring unit can give an alarm in real time to detect in advance the circuit breakage fault existing in the trip outlet circuit of the relay protection device, effectively avoiding phenomena such as the expansion of the power outage range caused by the refusal of the circuit breaker to operate.

[0007] The utility model adopts the following technical solutions to achieve the purpose:

[0008] A monitoring circuit for the trip outlet circuit of a relay protection device, wherein the trip outlet circuit consists of a protection device and a circuit breaker control cabinet that are connected to each other to form an electrical circuit; potential sensors are installed at both ends of the protection device, and the potential sensors are used to detect the potentials at both ends of the protection device respectively; the potential sensors are connected to a potential monitoring unit, and the potential monitoring unit is connected to the monitoring system through an alarm contact.

[0009] Specifically, the circuit breaker control cabinet has a positive power common terminal +KM, and the positive power common terminal +KM is connected in series with the positive power terminal CD at one end of the protection device.

[0010] Specifically, the trip outlet contact TJ in the protection device has a trip outlet contact TJ:1 terminal, and the trip outlet contact TJ:1 terminal is connected in series with the positive power terminal CD.

[0011] Specifically, a potential sensor RP1 is installed on the wire between the positive power common terminal +KM and the positive power terminal CD, and the potential sensor RP1 is connected to the potential monitoring unit.

[0012] Specifically, the circuit breaker control cabinet has a negative power common terminal -KM, and the negative power common terminal -KM is connected in series with the negative power terminal KD at one end of the protection device.

[0013] Specifically, the trip outlet contact TJ in the protection device has a trip outlet contact TJ:2 terminal, and the trip outlet contact TJ:2 terminal is connected in series with the negative power terminal KD.

[0014] Specifically, a trip outlet link CLP is provided on the wire between the negative power terminal KD and the trip outlet contact TJ:2 terminal; there is also a circuit breaker operating circuit in the circuit breaker control cabinet, and the circuit breaker operating circuit is connected in series on the wire between the negative power common terminal -KM and the negative power terminal KD.

[0015] Specifically, a potential sensor RP2 is installed on the wire between the trip outlet link CLP and the trip outlet contact TJ:2 terminal, and the potential sensor RP2 is connected to the potential monitoring unit.

[0016] Specifically, the alarm contact BJ in the potential monitoring unit has an alarm contact BJ:1 terminal and an alarm contact BJ:2 terminal; the alarm contact BJ:1 terminal is connected to the signal power common terminal +YD of the monitoring system, and the alarm contact BJ:2 terminal is connected to the signal power input terminal -YD of the monitoring system.

[0017] Specifically, the type of the potential sensor is a Hall effect sensor or an optocoupler.

[0018] In summary, due to the adoption of this technical solution, the beneficial effects of the present utility model are as follows:

[0019] By correspondingly installing two potential sensors on the trip outlet loop, the present utility model realizes continuous and dead - angle - free monitoring of the entire loop. The installation of potential sensors is not only convenient but also can be completely electrically isolated from the original loop, ensuring that while real - time monitoring is carried out, it will not cause any impact on the normal operation of the original system.

[0020] The potential monitoring unit in the present utility model can continuously collect and analyze data from potential sensors. Once an abnormal potential change appears in the trip outlet loop, it immediately triggers an alarm to alert the operation and maintenance personnel of potential disconnection faults. Such a real - time alarm mechanism enables faults to be identified and processed at an early stage, effectively avoiding the escalation of accidents and the expansion of the power outage scope caused by circuit breaker refusal to operate, thereby improving the operation efficiency of the power system and user satisfaction.

[0021] With the assistance of comprehensive monitoring and real - time alarm functions, power system managers can take measures in advance to repair potential hazards in the trip outlet loop, avoiding emergency shutdowns and large - scale overhauls caused by sudden failures. This type of monitoring scheme of the present utility model reduces unnecessary economic losses through simple structural features and improves the continuity and reliability of power supply. Brief Description of the Drawings

[0022] Figure 1 It is a schematic diagram of the monitoring circuit structure of the present utility model. Detailed Embodiment

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. Usually, the components of the embodiments of the present utility model described and illustrated herein can be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the present utility model provided in the drawings is not intended to limit the scope of the present utility model to be protected, but merely represents the selected embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present utility model.

[0025] Embodiment

[0026] A monitoring circuit for the trip outlet circuit of a relay protection device, where the trip outlet circuit consists of a protection device and a circuit breaker control cabinet that are interconnected to form an electrical circuit; potential sensors are installed at both ends of the protection device, and the potential sensors are used to detect the potentials at both ends of the protection device respectively; the potential sensors are connected to a potential monitoring unit, and the potential monitoring unit is connected to the monitoring system through an alarm contact.

[0027] In this embodiment, for the specific structure and detailed description of the above monitoring circuit, reference can be made to Figure 1 the schematic diagram. First, the circuit breaker control cabinet has a positive power common terminal +KM, and the positive power common terminal +KM is connected in series with the positive power terminal CD at one end of the protection device. The positive power common terminal +KM is used to connect to the positive pole of the DC220V power supply.

[0028] The trip outlet contact TJ in the protection device has a trip outlet contact TJ:1 terminal, and the trip outlet contact TJ:1 terminal is connected in series with the positive power terminal CD.

[0029] The potential sensors installed at both ends of the protection device are respectively the potential sensor RP1 at the positive power end and the potential sensor RP2 at the negative power end, and both are connected to the potential monitoring unit. The potential sensor RP1 is installed on the wire between the positive power common terminal +KM and the positive power terminal CD.

[0030] In this embodiment, the circuit breaker control cabinet has a negative power common terminal -KM, and the negative power common terminal -KM is connected in series with the negative power terminal KD at one end of the protection device. The negative power common terminal -KM is used to connect to the negative pole of the DC220V power supply.

[0031] The trip outlet contact TJ in the protection device has a trip outlet contact TJ:2 terminal, and the trip outlet contact TJ:2 terminal is connected in series with the negative power terminal KD.

[0032] In the refined structure of the trip outlet circuit, a trip outlet link CLP is provided on the wire between the negative power terminal KD and the trip outlet contact TJ:2 terminal; there is also a circuit breaker operation circuit in the circuit breaker control cabinet, and the circuit breaker operation circuit is connected in series on the wire between the negative power common terminal -KM and the negative power terminal KD.

[0033] Therefore, based on the refined structure, the preferred installation position of the potential sensor RP2 in this embodiment is on the wire between the trip outlet link CLP and the trip outlet contact TJ:2 terminal.

[0034] In this embodiment, the alarm contact BJ in the potential monitoring unit has an alarm contact BJ:1 terminal and an alarm contact BJ:2 terminal; the alarm contact BJ:1 terminal is connected to the signal power common terminal +YD of the monitoring system, and the alarm contact BJ:2 terminal is connected to the signal power input terminal -YD of the monitoring system.

[0035] Preferably, in this embodiment, the type of the potential sensor is a Hall effect sensor or an optocoupler. Both of them enable the potential sensor to have no electrical connection with the original wire and can monitor the potential, but have no impact on the operation of the original circuit.

[0036] In this embodiment, when the potential monitoring unit determines that the potential collected by the potential sensor RP1 and / or the potential sensor RP2 is abnormal, the alarm contact BJ: 1-2 will close and connect. The signal power supply of the monitoring system is DC24V, and its signal power supply common terminal +YD and the signal power supply input terminal -YD will conduct, and the monitoring system will thus display an alarm signal of "abnormality in the trip outlet circuit of the relay protection device".

[0037] The following is a detailed introduction to the working principle of the monitoring circuit of this embodiment.

[0038] When the equipment circuit operates normally, the DC220V power supply in the circuit breaker control cabinet operates normally, the circuit breaker operates in the closing position, and the trip outlet link CLP at the protection device is in the input state.

[0039] 1. Normal operating condition

[0040] There is a +110V potential to the ground at the DC220V positive power supply common terminal +KM of the circuit breaker control cabinet. Due to the installation position of the potential sensor RP1, a +110V potential can be monitored during normal operation.

[0041] There is a -110V potential to the ground at the DC220V negative power supply common terminal -KM of the circuit breaker control cabinet. Due to the installation position of the potential sensor RP2, a -110V potential can be monitored during normal operation.

[0042] Therefore, when the potential monitoring unit monitors a +110V potential by the potential sensor RP1 and a -110V potential by the potential sensor RP2, it determines that the trip outlet circuit of the relay protection device operates normally, the alarm contact BJ: 1-2 will not close, and the monitoring system will not alarm.

[0043] 2. Abnormal operating condition I

[0044] There is a +110V potential to the ground at the DC220V positive power supply common terminal +KM of the circuit breaker control cabinet. Due to the installation position of the potential sensor RP1, when there is a disconnection between the DC220V positive power supply common terminal +KM and the positive terminal CD, for example, the terminal wiring of the DC220V positive power supply common terminal +KM is loose, the potential sensor RP1 cannot monitor the potential.

[0045] There is a -110V potential to the ground at the DC220V negative power supply common terminal -KM of the circuit breaker control cabinet. Due to the installation position of the potential sensor RP2, a -110V potential can be monitored during normal operation.

[0046] Therefore, when the potential monitoring unit fails to monitor the potential by the potential sensor RP1 and the potential sensor RP2 monitors a potential of -110V, it is determined that the tripping outlet circuit of the relay protection device is abnormal, and the alarm contact BJ: 1-2 is closed. The common terminal +YD of the signal power supply and the signal power supply input terminal -YD of the monitoring system will be conducted, and the monitoring system will thus give an alarm.

[0047] 3. Abnormal operating condition 2

[0048] The positive power common terminal +KM of the DC220V in the circuit breaker control cabinet has a ground potential of +110V. Due to the installation position of the potential sensor RP1, a potential of +110V can be monitored during normal operation.

[0049] The negative power common terminal -KM of the DC220V in the circuit breaker control cabinet has a ground potential of -110V. Due to the installation position of the potential sensor RP2, when there is a break between the tripping outlet connection piece CLP and the negative power common terminal -KM of the DC220V, the potential sensor RP2 fails to monitor the potential.

[0050] Therefore, when the potential monitoring unit monitors a potential of +110V by the potential sensor RP1 and fails to monitor the potential by the potential sensor RP2, it is determined that the tripping outlet circuit of the relay protection device is abnormal, and the alarm contact BJ: 1-2 is closed. The common terminal +YD of the signal power supply and the signal power supply input terminal -YD of the monitoring system will be conducted, and the monitoring system will thus give an alarm.

[0051] 4. Abnormal operating condition 3

[0052] The positive power common terminal +KM of the DC220V in the circuit breaker control cabinet has a ground potential of +110V. Due to the installation position of the potential sensor RP1, when there is a break between the positive power common terminal +KM of the DC220V and the positive power terminal CD, for example, the terminal connection of the positive power common terminal +KM of the DC220V is loose, the potential sensor RP1 fails to monitor the potential.

[0053] The negative power common terminal -KM of the DC220V in the circuit breaker control cabinet has a ground potential of -110V. Due to the installation position of the potential sensor RP2, when there is a break between the tripping outlet connection piece CLP and the negative power common terminal -KM of the DC220V, the potential sensor RP2 fails to monitor the potential.

[0054] Therefore, when the potential monitoring unit fails to monitor the potential by the potential sensor RP1 and fails to monitor the potential by the potential sensor RP2, it is determined that the tripping outlet circuit of the relay protection device is abnormal, and the alarm contact BJ: 1-2 is closed. The common terminal +YD of the signal power supply and the signal power supply input terminal -YD of the monitoring system will be conducted, and the monitoring system will thus give an alarm.

Claims

1. A monitoring circuit for the tripping outlet circuit of a relay protection device, wherein the tripping outlet circuit consists of a protection device and a circuit breaker control cabinet that are interconnected to form an electrical circuit; characterized in that: Potential sensors are installed at both ends of the protection device. The potential sensors are used to detect the potentials at both ends of the protection device respectively; the potential sensors are connected to a potential monitoring unit, and the potential monitoring unit is connected to the monitoring system through an alarm contact.

2. The monitoring circuit of the tripping outlet loop of the relay protection device according to claim 1, wherein: The breaker control cabinet has a positive power common terminal +KM, and the positive power common terminal +KM is connected in series with the positive power terminal CD at one end of the protection device.

3. The monitoring circuit of the tripping outlet circuit of the relay protection device according to claim 2, characterized in that: The trip outlet contact TJ in the protection device has a trip outlet contact TJ:1 terminal, and the trip outlet contact TJ:1 terminal is connected in series with the positive power terminal CD.

4. The monitoring circuit of the tripping output loop of the relay protection device according to claim 2, characterized in that: A potential sensor RP1 is installed on the wire between the positive power common terminal +KM and the positive power terminal CD, and the potential sensor RP1 is connected to the potential monitoring unit.

5. The monitoring circuit of the tripping outlet loop of the relay protection device according to claim 1 or 2, characterized in that: The breaker control cabinet has a negative power common terminal -KM, and the negative power common terminal -KM is connected in series with the negative power terminal KD at one end of the protection device.

6. The monitoring circuit of the tripping outlet loop of the relay protection device according to claim 5, characterized in that: The trip outlet contact TJ in the protection device has a trip outlet contact TJ:2 terminal, and the trip outlet contact TJ:2 terminal is connected in series with the negative power terminal KD.

7. The monitoring circuit of the tripping outlet circuit of the relay protection device according to claim 6, characterized in that: A trip outlet link CLP is provided on the wire between the negative power terminal KD and the trip outlet contact TJ:2 terminal; there is also a breaker operating circuit in the breaker control cabinet, and the breaker operating circuit is connected in series on the wire between the negative power common terminal -KM and the negative power terminal KD.

8. The monitoring circuit for the tripping outlet circuit of the relay protection device according to claim 7, characterized in that: A potential sensor RP2 is installed on the wire between the trip outlet link CLP and the trip outlet contact TJ:2 terminal, and the potential sensor RP2 is connected to the potential monitoring unit.

9. The monitoring circuit of the tripping outlet loop of the relay protection device according to claim 1, characterized in that: The alarm contact BJ in the potential monitoring unit has an alarm contact BJ:1 terminal and an alarm contact BJ:2 terminal; the alarm contact BJ:1 terminal is connected to the signal power common terminal +YD of the monitoring system, and the alarm contact BJ:2 terminal is connected to the signal power input terminal -YD of the monitoring system.

10. The monitoring circuit of the tripping outlet loop of the relay protection device according to claim 1, characterized in that: The type of the potential sensor is a Hall effect sensor or an optocoupler.

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