High-voltage circuit breaker control system based on short-circuit current detection

Abstract

The invention discloses a high-voltage circuit breaker control system based on short-circuit current detection, and relates to the technical field of short-circuit current detection. A three-phase short-circuit current sensing module collects three-phase short-circuit current and converts the three-phase short-circuit current into a first analog voltage signal; the signal conditioning module outputs a second analog voltage signal and divides the second analog voltage signal into a third analog voltage signal, a fourth analog voltage signal and a fifth analog voltage signal; the first analog-to-digital conversion module outputs first and second digital voltage signals; the second analog-to-digital conversion module outputs a third digital voltage signal; the sampling CPU module obtains a first operation signal based on the first digital voltage signal and the second digital voltage signal; the main control CPU module obtains a second operation signal based on the third digital voltage signal, and obtains a fault-tolerant operation signal based on the first and second operation signals; and the power driving module controls the breaking of the contact of the high-voltage circuit breaker based on the fault-tolerant operation signal. According to the invention, by reducing the detection error of the short-circuit current and shortening the detection time, the phenomenon that the control of the high-voltage circuit breaker is easily misjudged and broken can be reduced.

Description

Technical Field

[0001] This application relates to the field of short-circuit current detection technology, and in particular to a high-voltage circuit breaker control system based on short-circuit current detection. Background Technology

[0002] High-voltage circuit breakers are switching devices used in power systems to control, protect, and isolate high-voltage circuits. When a short-circuit fault occurs in a line, they quickly disconnect the power supply, reduce the area of ​​power outage, prevent the accident from escalating, protect electrical equipment from damage, and ensure the safe operation of the fault-free parts of the power system. Therefore, researching rapid short-circuit current detection technologies and methods for high-voltage circuit breakers is particularly important.

[0003] Traditional technologies for detecting short-circuit current in high-voltage circuit breakers employ the following methods: 1. Thermal overload protection: Overload of the induced current in the circuit breaker's internal thermal element causes heating, triggering the circuit breaker to trip. 2. Magnetic overload protection: A sudden increase in the induced current in the magnetic element causes a change in the magnetic field, triggering the circuit breaker to trip. 3. Electronic protection: The circuit breaker is equipped with electronic protection devices that detect current changes through electronic components and circuits, determine whether to interrupt the circuit based on preset parameters, provide precise and adjustable protection functions, and trigger the circuit breaker to trip.

[0004] However, the aforementioned technologies have long detection times and large detection errors, making it easy for high-voltage circuit breakers to be misjudged or misconnected. Summary of the Invention

[0005] The purpose of this application is to provide a high-voltage circuit breaker control system based on short-circuit current detection, so as to reduce the detection error of short-circuit current and shorten the detection time, thereby reducing the phenomenon of misjudgment and misdiagnosis that is prone to occur in the control of high-voltage circuit breakers.

[0006] To achieve the above objectives, this application provides the following solution.

[0007] This application provides a high-voltage circuit breaker control system based on short-circuit current detection, including: a second analog-to-digital converter module and a three-phase short-circuit current sensing module, a signal conditioning module, a first analog-to-digital converter module, a sampling CPU module, a main control CPU module, and a power drive module connected in sequence; the second analog-to-digital converter module is connected to the signal conditioning module and the main control CPU module respectively, the three-phase short-circuit current sensing module is connected to the incoming side of the high-voltage circuit breaker, and the power drive module is connected to the contacts of the high-voltage circuit breaker; The three-phase short-circuit current sensing module is used to collect the three-phase short-circuit current at the input end and convert the three-phase short-circuit current into a first analog voltage signal. The signal conditioning module is used to perform voltage following and impedance transformation on the first analog voltage signal to obtain a second analog voltage signal, divide the second analog voltage signal into a third analog voltage signal, a fourth analog voltage signal and a fifth analog voltage signal, and send the third analog voltage signal and the fourth analog voltage signal to the first analog-to-digital conversion module, and send the fifth analog voltage signal to the second analog-to-digital conversion module; The first analog-to-digital conversion module is used to perform analog-to-digital conversion on the third analog voltage signal and the fourth analog voltage signal respectively to obtain the first digital voltage signal and the second digital voltage signal; The second analog-to-digital converter module is used to perform analog-to-digital conversion on the fifth analog voltage signal to obtain the third digital voltage signal; The sampling CPU module is used to perform calculations on the first digital voltage signal and the second digital voltage signal to obtain a first calculation signal, and then send the first calculation signal to the main control CPU module. The main control CPU module is used to process the third digital voltage signal to obtain the second operation signal, and to perform a fault-tolerant operation based on the first operation signal and the second operation signal to obtain the fault-tolerant operation signal. The power drive module is used to control the contact disconnection of the high-voltage circuit breaker based on the fault-tolerant operation signal.

[0008] In one embodiment, the three-phase short-circuit current sensing module includes: a two-stage current transformer and a Hall sensor; The input terminal of the two-stage current transformer is connected to the incoming line terminal, the output terminal of the two-stage current transformer is connected to the input terminal of the Hall sensor, and the output terminal of the Hall sensor is connected to the input terminal of the signal conditioning module. The two-stage current transformer is used to collect the three-phase short-circuit current at the incoming end; The Hall sensor is used to convert the three-phase short-circuit current into a first analog voltage signal.

[0009] In one embodiment, the high-voltage circuit breaker control system based on short-circuit current detection further includes: a human-machine interface module; the human-machine interface module is connected to the main control CPU module; The human-machine interface module is used to display the waveform of the three-phase short-circuit current in real time.

[0010] In one embodiment, the high-voltage circuit breaker control system based on short-circuit current detection further includes: a waveform recording memory module; the waveform recording memory module is connected to the main control CPU module; The waveform recording memory module is used to store the waveform of the three-phase short-circuit current in real time.

[0011] In one embodiment, the signal conditioning module includes: a signal conditioning unit and a voltage follower; The input terminal of the signal conditioning unit is connected to the three-phase short-circuit current sensing module, the output terminal of the signal conditioning unit is connected to the input terminal of the voltage follower, and the output terminal of the voltage follower is connected to the first analog-to-digital conversion module and the second analog-to-digital conversion module respectively. The signal conditioning unit is used to perform voltage following and impedance transformation on the first analog voltage signal to obtain a second analog voltage signal; The voltage follower is used to split the second analog voltage signal into a third analog voltage signal, a fourth analog voltage signal, and a fifth analog voltage signal, and send the third analog voltage signal and the fourth analog voltage signal to the first analog-to-digital converter module, and send the fifth analog voltage signal to the second analog-to-digital converter module.

[0012] In one embodiment, the power drive module includes: a drive unit, a MOSFET device, an electromagnetic coil, an armature, and a tripping mechanism connected in sequence; the tripping mechanism is connected to the contacts of a high-voltage circuit breaker. Under the control of the received fault-tolerant operation signal, the driving unit drives the electromagnetic coil to generate a magnetic field, causing the armature to be directly attracted, triggering the tripping mechanism, and realizing the disconnection of the high-voltage circuit breaker contacts.

[0013] In one embodiment, the formula for calculating the first analog voltage signal in the Hall sensor is: ; in, This is the first analog voltage signal; Hall coefficient; This refers to the three-phase short-circuit current. The magnetic flux density is perpendicular to the plane of the Hall sensor. The thickness of the Hall sensor.

[0014] In one embodiment, both the first analog-to-digital conversion module and the second analog-to-digital conversion module employ a 12-bit high-speed ADC circuit.

[0015] In one embodiment, the MOSFET device is a half-bridge gate-driven high-voltage MOSFET.

[0016] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application discloses a high-voltage circuit breaker control system based on short-circuit current detection. When a short-circuit fault occurs in a power distribution line, the three-phase short-circuit current sensing module instantly detects the short-circuit current. After signal conditioning, digital conversion, and rapid calculation, the power drive module drives an ultra-fast explosive bridge to explode, cutting off the high-voltage power supply in a short time. A dual-CPU module is used for differential comparison and fault-tolerant rapid calculation. For instantaneous short-circuit currents generated by non-abnormal conditions such as lightning strikes, the dual-CPU data comparison fault-tolerant algorithm avoids malfunctions of the high-voltage circuit breaker, thereby ensuring the normal operation of the power distribution line. In summary, this application reduces the detection error of short-circuit current and shortens the detection time, thus reducing the possibility of misjudgment and misoperation in the control of high-voltage circuit breakers. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a structural diagram of a high-voltage circuit breaker control system based on short-circuit current detection in one embodiment of this application; Figure 2 This is a flowchart illustrating the execution steps of a high-voltage circuit breaker control system based on short-circuit current detection. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] The purpose of this application is to provide a high-voltage circuit breaker control system based on short-circuit current detection, which aims to reduce the detection error of short-circuit current and shorten the detection time, thereby reducing the phenomenon of misjudgment and misdiagnosis that is prone to occur in the control of high-voltage circuit breakers.

[0021] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] In one exemplary embodiment, such as Figure 1 and Figure 2As shown, a high-voltage circuit breaker control system based on short-circuit current detection is provided, including: a second analog-to-digital conversion module (high-speed A / D module 2) and a three-phase short-circuit current sensing module, a signal conditioning module, a first analog-to-digital conversion module (high-speed A / D module 1), a sampling CPU module, a main control CPU module, and a power drive module connected in sequence; the second analog-to-digital conversion module is connected to the signal conditioning module and the main control CPU module respectively, the three-phase short-circuit current sensing module is connected to the incoming line side (TA) of the high-voltage circuit breaker, and the power drive module is connected to the contacts of the high-voltage circuit breaker; The three-phase short-circuit current sensing module is used to collect the three-phase short-circuit current at the input end and convert the three-phase short-circuit current into a first analog voltage signal. The signal conditioning module is used to perform voltage following and impedance transformation on the first analog voltage signal to obtain the second analog voltage signal, divide the second analog voltage signal into a third analog voltage signal, a fourth analog voltage signal and a fifth analog voltage signal, and send the third analog voltage signal and the fourth analog voltage signal to the first analog-to-digital converter module, and send the fifth analog voltage signal to the second analog-to-digital converter module; The first analog-to-digital conversion module is used to perform analog-to-digital conversion on the third analog voltage signal and the fourth analog voltage signal respectively to obtain the first digital voltage signal and the second digital voltage signal; The second analog-to-digital conversion module is used to convert the fifth analog voltage signal into a third digital voltage signal; The sampling CPU module is used to perform calculations on the first digital voltage signal and the second digital voltage signal to obtain the first calculation signal, and then send the first calculation signal to the main control CPU module. The main control CPU module is used to process the third digital voltage signal to obtain the second operation signal, and to perform fault-tolerant operation based on the first operation signal and the second operation signal to obtain the fault-tolerant operation signal. The power drive module is used to control the contact disconnection of a high-voltage circuit breaker based on fault-tolerant operation signals.

[0023] As an optional implementation, the three-phase short-circuit current sensing module includes: a two-stage current transformer and a Hall sensor; The input terminals of the two-stage current transformers are connected to the incoming line terminals, the output terminals of the two-stage current transformers are connected to the input terminals of the Hall sensor, and the output terminals of the Hall sensor are connected to the input terminals of the signal conditioning module. Two-stage current transformers are used to collect the three-phase short-circuit current at the incoming end; Hall effect sensors are used to convert three-phase short-circuit currents into a first analog voltage signal.

[0024] As an optional implementation, the high-voltage circuit breaker control system based on short-circuit current detection also includes: a Human-Machine Interface (HMI) module; the HMI module is connected to the main control CPU module; The human-machine interface module is used to display the waveform of the three-phase short-circuit current in real time.

[0025] As an optional implementation, the high-voltage circuit breaker control system based on short-circuit current detection further includes: a waveform recording memory module; the waveform recording memory module is connected to the main control CPU module; The waveform recording memory module is used to store the waveform of the three-phase short-circuit current in real time.

[0026] Specifically, it is equipped with a large-capacity storage unit, and the recording time for the waveform of the three-phase short-circuit current is 200ms~800ms.

[0027] As an optional implementation, the signal conditioning module includes: a signal conditioning unit and a voltage follower; The input terminal of the signal conditioning unit is connected to the three-phase short-circuit current sensing module, the output terminal of the signal conditioning unit is connected to the input terminal of the voltage follower, and the output terminal of the voltage follower is connected to the first analog-to-digital converter module and the second analog-to-digital converter module respectively. The signal conditioning unit is used to perform voltage following and impedance transformation on the first analog voltage signal to obtain the second analog voltage signal; The voltage follower is used to split the second analog voltage signal into a third analog voltage signal, a fourth analog voltage signal, and a fifth analog voltage signal, and sends the third analog voltage signal and the fourth analog voltage signal to the first analog-to-digital converter module, and sends the fifth analog voltage signal to the second analog-to-digital converter module.

[0028] As an optional implementation, the power drive module includes: a drive unit, a MOSFET device, an electromagnetic coil, an armature, and a tripping mechanism connected in sequence; the tripping mechanism is connected to the contacts of the high-voltage circuit breaker; Under the control of the received fault-tolerant operation signal, the drive unit drives the electromagnetic coil to generate a magnetic field, causing the armature to be directly attracted, triggering the tripping mechanism, and realizing the disconnection of the high-voltage circuit breaker contacts.

[0029] As an optional implementation, the formula for calculating the first analog voltage signal in the Hall sensor is: ; in, This is the first analog voltage signal; Hall coefficient; This refers to the three-phase short-circuit current. The magnetic flux density is perpendicular to the plane of the Hall sensor. The thickness of the Hall sensor.

[0030] As an optional implementation, both the first analog-to-digital conversion module and the second analog-to-digital conversion module employ a 12-bit high-speed ADC circuit.

[0031] As an alternative implementation, the MOSFET device is a half-bridge gate-driven high-voltage MOSFET.

[0032] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0033] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the system and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A high-voltage circuit breaker control system based on short-circuit current detection, characterized in that, The high-voltage circuit breaker control system based on short-circuit current detection includes: a second analog-to-digital converter module and a three-phase short-circuit current sensing module, a signal conditioning module, a first analog-to-digital converter module, a sampling CPU module, a main control CPU module, and a power drive module connected in sequence; the second analog-to-digital converter module is connected to the signal conditioning module and the main control CPU module respectively, the three-phase short-circuit current sensing module is connected to the incoming side of the high-voltage circuit breaker, and the power drive module is connected to the contacts of the high-voltage circuit breaker; The three-phase short-circuit current sensing module is used to collect the three-phase short-circuit current at the input end and convert the three-phase short-circuit current into a first analog voltage signal. The signal conditioning module is used to perform voltage following and impedance transformation on the first analog voltage signal to obtain a second analog voltage signal, divide the second analog voltage signal into a third analog voltage signal, a fourth analog voltage signal and a fifth analog voltage signal, and send the third analog voltage signal and the fourth analog voltage signal to the first analog-to-digital conversion module, and send the fifth analog voltage signal to the second analog-to-digital conversion module; The first analog-to-digital conversion module is used to perform analog-to-digital conversion on the third analog voltage signal and the fourth analog voltage signal respectively to obtain the first digital voltage signal and the second digital voltage signal; The second analog-to-digital converter module is used to perform analog-to-digital conversion on the fifth analog voltage signal to obtain the third digital voltage signal; The sampling CPU module is used to perform calculations on the first digital voltage signal and the second digital voltage signal to obtain a first calculation signal, and then send the first calculation signal to the main control CPU module. The main control CPU module is used to process the third digital voltage signal to obtain the second operation signal, and to perform a fault-tolerant operation based on the first operation signal and the second operation signal to obtain the fault-tolerant operation signal. The power drive module is used to control the contact disconnection of the high-voltage circuit breaker based on the fault-tolerant operation signal.

2. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 1, characterized in that, The three-phase short-circuit current sensing module includes: a two-stage current transformer and a Hall sensor; The input terminal of the two-stage current transformer is connected to the incoming line terminal, the output terminal of the two-stage current transformer is connected to the input terminal of the Hall sensor, and the output terminal of the Hall sensor is connected to the input terminal of the signal conditioning module. The two-stage current transformer is used to collect the three-phase short-circuit current at the incoming end; The Hall sensor is used to convert the three-phase short-circuit current into a first analog voltage signal.

3. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 1, characterized in that, The high-voltage circuit breaker control system based on short-circuit current detection further includes: a human-machine interface module; the human-machine interface module is connected to the main control CPU module; The human-machine interface module is used to display the waveform of the three-phase short-circuit current in real time.

4. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 1, characterized in that, The high-voltage circuit breaker control system based on short-circuit current detection further includes: a waveform recording and storage module; the waveform recording and storage module is connected to the main control CPU module; The waveform recording memory module is used to store the waveform of the three-phase short-circuit current in real time.

5. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 1, characterized in that, The signal conditioning module includes: a signal conditioning unit and a voltage follower; The input terminal of the signal conditioning unit is connected to the three-phase short-circuit current sensing module, the output terminal of the signal conditioning unit is connected to the input terminal of the voltage follower, and the output terminal of the voltage follower is connected to the first analog-to-digital conversion module and the second analog-to-digital conversion module respectively. The signal conditioning unit is used to perform voltage following and impedance transformation on the first analog voltage signal to obtain a second analog voltage signal; The voltage follower is used to split the second analog voltage signal into a third analog voltage signal, a fourth analog voltage signal, and a fifth analog voltage signal, and send the third analog voltage signal and the fourth analog voltage signal to the first analog-to-digital converter module, and send the fifth analog voltage signal to the second analog-to-digital converter module.

6. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 1, characterized in that, The power drive module includes: a drive unit, a MOSFET device, an electromagnetic coil, an armature, and a tripping mechanism connected in sequence; the tripping mechanism is connected to the contacts of the high-voltage circuit breaker. Under the control of the received fault-tolerant operation signal, the driving unit drives the electromagnetic coil to generate a magnetic field, causing the armature to be directly attracted, triggering the tripping mechanism, and realizing the disconnection of the high-voltage circuit breaker contacts.

7. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 2, characterized in that, In a Hall sensor, the formula for calculating the first analog voltage signal is: ； in, This is the first analog voltage signal; Hall coefficient; This refers to the three-phase short-circuit current. The magnetic flux density is perpendicular to the plane of the Hall sensor. The thickness of the Hall sensor.

8. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 1, characterized in that, Both the first analog-to-digital conversion module and the second analog-to-digital conversion module use a 12-bit high-speed ADC circuit.

9. The high-voltage circuit breaker control system based on short-circuit current detection according to claim 6, characterized in that, The MOSFET device is a half-bridge gate-driven high-voltage MOSFET.

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