Breaker opening and closing period monitoring system

Abstract

The invention discloses a circuit breaker opening and closing period monitoring system, which comprises a Hall current sensor, an output signal conditioning circuit, a high-frequency signal coupling circuit, a high-frequency signal decoupling circuit, a DSP microprocessor, a liquid crystal display interface, an alarm module and a communication module, and is characterized in that one end of the Hall current sensor is connected with an opening and closing coil of a target circuit breaker; the output end of the output signal conditioning circuit is connected with the signal receiving end of the DSP microprocessor; the input end of the high-frequency signal coupling circuit is connected with the signal output end of the DSP microprocessor; the output end of the high-frequency signal decoupling circuit is connected with the signal capturing end of the DSP microprocessor; the DSP microprocessor is used for sending a low-voltage high-frequency signal to the high-frequency signal coupling circuit after receiving the voltage signal, and receiving the low-voltage high-frequency signal sent by the high-frequency signal decoupling circuit at the same time. According to the invention, on-line detection of the opening and closing period of the power supply equipment is realized.

Description

Technical Field

[0001] The present application relates to the technical field of power monitoring, and in particular to a circuit breaker opening and closing cycle monitoring system. Background Art

[0002] In the complex and huge power system, circuit breakers play a vital role and are key equipment to ensure the stable operation, fault isolation and safety control of the power network. The performance stability and reliability of circuit breakers are directly related to the safety and reliability of the entire power system. Once a circuit breaker fails or its performance degrades, it may cause widespread power outages and even lead to more serious power accidents.

[0003] Traditional circuit breaker monitoring methods mainly rely on manual inspections and periodic tests. Manual inspections usually include appearance inspections, lubrication and tightening of mechanical parts, and simple performance tests, while periodic tests cover more detailed electrical performance tests, such as insulation resistance, power frequency withstand voltage, and impulse withstand voltage. However, the process of manual inspections and periodic tests is extremely time-consuming and labor-intensive. For large power systems, which may contain hundreds or thousands of circuit breakers, each circuit breaker needs to be inspected and tested in detail, which is undoubtedly a difficult task. In addition, the inspection and test cycles are also long, and usually only some more obvious faults or performance degradations can be covered. For those hidden, intermittent or gradually developing faults, they may not be discovered and handled in time. Traditional monitoring methods cannot meet the needs of smart grids for real-time monitoring of circuit breakers. Summary of the invention

[0004] The present application aims to provide a circuit breaker opening and closing cycle monitoring system to solve the technical problem of how to improve the real-time performance of circuit breaker monitoring.

[0005] In order to solve the above technical problems, the embodiment of the present application provides a circuit breaker opening and closing cycle monitoring system, including: a Hall current sensor, an output signal conditioning circuit, a high-frequency signal coupling circuit, a high-frequency signal decoupling circuit, a DSP microprocessor, a liquid crystal display interface, an alarm module and a communication module, wherein:

[0006] One end of the Hall current sensor is connected to the opening and closing coil of the target circuit breaker, and is used to send the sensed current signal of the opening and closing coil of the target circuit breaker to the output signal conditioning circuit;

[0007] The output end of the output signal conditioning circuit is connected to the signal receiving end of the DSP microprocessor, and is used to receive the current signal output by the Hall current sensor, and convert and condition the current signal, and send the voltage signal obtained after conditioning to the DSP microprocessor;

[0008] The input end of the high-frequency signal coupling circuit is connected to the signal output end of the DSP microprocessor, and is used to receive the low-voltage high-frequency signal generated by the DSP microprocessor, and couple the low-voltage high-frequency signal to the high-voltage power frequency AC signal at one end of the moving and static contacts of the target circuit breaker;

[0009] The output end of the high-frequency signal decoupling circuit is connected to the signal capture end of the DSP microprocessor, and is used to decouple the low-voltage high-frequency signal from the high-voltage power frequency AC signal at the other end of the moving and static contacts of the target circuit breaker, and transmit the low-voltage high-frequency signal to the DSP microprocessor;

[0010] The DSP microprocessor is used to send the low-voltage high-frequency signal to the high-frequency signal coupling circuit after receiving the voltage signal, and simultaneously receive the low-voltage high-frequency signal sent by the high-frequency signal decoupling circuit.

[0011] As one of the preferred schemes, the output signal conditioning circuit includes a sampling resistor and a Schmitt trigger gate circuit chip, one end of the sampling resistor is connected to the output end of the Hall current sensor, the other end of the sampling resistor is connected to the input end of the Schmitt trigger gate circuit chip, and the output end of the Schmitt trigger gate circuit chip is connected to the DSP microprocessor unit.

[0012] As one of the preferred solutions, the sampling resistor is used to convert the current signal of the Hall current sensor into a voltage signal, and the Schmitt trigger gate circuit chip is used to preprocess the voltage signal, and the preprocessing includes shaping and noise filtering.

[0013] As one of the preferred schemes, the high-frequency signal coupling circuit includes an optoelectronic isolator, a high-voltage side loop, a high-frequency coupling transformer and a low-voltage side loop. The input end of the optoelectronic isolator is connected to the DSP microprocessor, the output end of the optoelectronic isolator is connected to the high-voltage side loop, and the high-voltage side loop is connected to the low-voltage side loop through the high-frequency coupling transformer.

[0014] As one of the preferred solutions, the photoelectric isolator is used to isolate the low-voltage high-frequency signal sent by the DSP microprocessor from the high-voltage side circuit in the high-frequency signal coupling circuit;

[0015] The high-frequency coupling transformer is used to isolate the high-voltage side circuit from the low-voltage side circuit in the high-frequency signal coupling circuit.

[0016] As one of the preferred solutions, the high-voltage side circuit includes a DC power supply, and the DC power supply is used to amplify the low-voltage high-frequency signal.

[0017] As one of the preferred solutions, the low-voltage side loop includes a first inductor and a high-voltage power coupling capacitor, and the first inductor is used to transmit the low-voltage high-frequency signal in the low-voltage side loop along a preset path;

[0018] The high-voltage power coupling capacitor is used to couple the low-voltage high-frequency signal to the high-voltage industrial frequency alternating current at one end of the moving and static contacts of the target circuit breaker.

[0019] As one of the preferred solutions, a bidirectional diode is provided between the first inductor and the high-voltage power coupling capacitor, and the bidirectional diode is used to protect the high-frequency signal coupling circuit.

[0020] As one preferred solution, the high-frequency signal decoupling circuit includes a power decoupling capacitor, a high-frequency isolation transformer, a second inductor and an optical coupling chip, wherein:

[0021] The power decoupling capacitor is used to decouple the low-voltage high-frequency signal from the other end of the moving and static contacts of the target circuit breaker;

[0022] The second inductor is used for transmitting the low-voltage high-frequency signal along a preset path;

[0023] The high-frequency isolation transformer is used to transmit the low-voltage high-frequency signal obtained by decoupling from the high-voltage end of the high-frequency signal decoupling circuit to the low-voltage end;

[0024] The optical coupling chip is used to perform electrical isolation and level conversion on the low-voltage high-frequency signal at the low-voltage end.

[0025] As one of the preferred solutions, the liquid crystal display interface, the alarm module and the communication module are respectively connected to the DSP microprocessor, wherein:

[0026] The liquid crystal display interface is used to display the monitoring data analyzed by the DSP microprocessor;

[0027] The alarm module is used to perform alarm processing when the monitoring data reaches a preset condition;

[0028] The communication module is used to upload the monitoring data to a data center.

[0029] Compared with the prior art, the beneficial effects of the embodiments of the present application are at least one of the following:

[0030] 1) The system of the present application can monitor key parameters such as the opening and closing cycle of the circuit breaker in real time, detect and handle potential faults in a timely manner, and improve the stability and reliability of the power system.

[0031] 2) The application of Hall current sensor and high-frequency signal coupling and decoupling circuit enables the system to measure the current and voltage signals of the circuit breaker with high precision, improving the accuracy and reliability of the data.

[0032] 3) The DSP microprocessor unit can perform intelligent analysis and diagnosis based on the real-time monitored data, accurately determine the status of the circuit breaker, and avoid the errors and uncertainties of manual judgment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of a circuit breaker opening and closing cycle monitoring system in one embodiment of the present application;

[0034] Figure 2 It is a schematic diagram of a Hall current sensor output conditioning circuit in one embodiment of the present application;

[0035] Figure 3 is a schematic diagram of a high-frequency signal coupling circuit in one embodiment of the present application;

[0036] Figure 4 is a schematic diagram of a high-frequency signal coupling circuit in one embodiment of the present application;

[0037] Figure 5 It is a schematic diagram of the external interrupt 1 processing procedure in one embodiment of the present application;

[0038] Figure 6 This is a flow chart of the external interrupt 2 processing program in one embodiment of the present application. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] In the description of this application, the terms "first", "second", "third", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", etc. may explicitly or implicitly include one or more of the feature. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0041] In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. The terms "vertical", "horizontal", "left", "right", "upper", "lower" and similar expressions used in this article are only for illustrative purposes, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. The term "and / or" used in this article includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] In the description of this application, it should be noted that, unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by those skilled in the art. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0043] An embodiment of the present application provides a circuit breaker opening and closing cycle monitoring system. For details, see Figure 1 , Figure 1 The structure diagram of the circuit breaker opening and closing cycle monitoring system in one embodiment of the present application is shown, which includes: a Hall current sensor, an output signal conditioning circuit, a high-frequency signal coupling circuit, a high-frequency signal decoupling circuit, a DSP microprocessor, a liquid crystal display interface, an alarm module and a communication module, wherein:

[0044] One end of the Hall current sensor is connected to the opening and closing coil of the target circuit breaker, and is used to send the sensed current signal of the opening and closing coil of the target circuit breaker to the output signal conditioning circuit;

[0045] The output end of the output signal conditioning circuit is connected to the signal receiving end of the DSP microprocessor, and is used to receive the current signal output by the Hall current sensor, and convert and condition the current signal, and send the conditioned voltage signal to the DSP microprocessor;

[0046] The input end of the high-frequency signal coupling circuit is connected to the signal output end of the DSP microprocessor, and is used to receive the low-voltage high-frequency signal generated by the DSP microprocessor, and couple the low-voltage high-frequency signal to the high-voltage power frequency AC signal at one end of the moving and static contacts of the target circuit breaker;

[0047] The output end of the high-frequency signal decoupling circuit is connected to the signal capture end of the DSP microprocessor, and is used to decouple the low-voltage high-frequency signal from the high-voltage power frequency AC signal at the other end of the moving and static contacts of the target circuit breaker, and transmit the low-voltage high-frequency signal to the DSP microprocessor;

[0048] The DSP microprocessor is used for sending a low-voltage high-frequency signal to the high-frequency signal coupling circuit after receiving the voltage signal, and simultaneously receiving the low-voltage high-frequency signal sent by the high-frequency signal decoupling circuit.

[0049] Specifically, the Hall current sensor is a sensor based on the Hall effect, which can measure current in a contactless manner. In the system of the present application, one end of the Hall current sensor is connected to the opening and closing coil of the target circuit breaker to monitor the current changes in the coil. When current passes through the opening and closing coil, a magnetic field is generated around it. The Hall current sensor indirectly measures the magnitude of the current by detecting the changes in this magnetic field. When the circuit breaker performs an opening and closing operation, the current in the coil will change, and this change will be captured by the Hall sensor and converted into an electrical signal.

[0050] The output signal conditioning circuit is responsible for receiving the current signal output by the Hall current sensor and performing appropriate conversion and conditioning on it so that the DSP microprocessor can read it accurately. The conditioning circuit includes functions such as amplification, filtering and level conversion. It first amplifies the weak current signal output by the Hall sensor to an appropriate level, then removes noise and interference through a filter, and finally performs level conversion to match the signal with the input requirements of the DSP microprocessor.

[0051] As one of the preferred solutions, the output signal conditioning circuit includes a sampling resistor and a Schmitt trigger gate circuit chip, one end of the sampling resistor is connected to the output end of the Hall current sensor, the other end of the sampling resistor is connected to the input end of the Schmitt trigger gate circuit chip, and the output end of the Schmitt trigger gate circuit chip is connected to the DSP microprocessor unit.

[0052] For details, see Figure 2 , Figure 2 The output signal conditioning circuit schematic diagram of one embodiment of the present application is shown. As the input part of the circuit, the Hall current sensor is used to monitor the current change of the circuit breaker opening and closing coil. When the current passes through the coil, the Hall sensor will output a weak current signal proportional to it. The sampling resistor R5 is used to convert the weak current signal output by the Hall current sensor into a voltage signal. By selecting a suitable resistance value, the current signal can be converted into a voltage range suitable for processing by the DSP microprocessor.

[0053] The Schmitt trigger gate circuit chip U2 is used to shape and filter the voltage signal. It is used to convert the irregular voltage signal into a relatively ideal rectangular pulse signal, thereby eliminating noise and interference and improving the stability and reliability of the signal. The Schmitt trigger has a hysteresis characteristic, that is, when the input voltage reaches a certain threshold, the output will flip; and when the input voltage drops to another lower threshold, the output will flip again. This characteristic helps to resist noise interference and ensure the accuracy of the signal.

[0054] When the circuit breaker opening and closing coil is energized, the Hall current sensor will output a weak current signal proportional to it. By utilizing the Hall current sensor's fast response characteristics to electrical signals (microsecond level), the energized moment of the circuit breaker opening and closing coil can be accurately obtained. When the current signal passes through the sampling resistor R5, a corresponding voltage signal will be generated. The generated voltage signal is shaped and filtered by the Schmidt trigger gate circuit chip U2. U2 converts the irregular voltage signal into a regular rectangular pulse signal and eliminates noise and interference.

[0055] During the shaping process, the Schmitt trigger will judge the threshold of the input voltage according to its hysteresis characteristics, thereby ensuring the stability and accuracy of the output signal. The rectangular pulse signal after shaping and noise filtering is transmitted to the external interrupt pin of the DSP microprocessor. When the DSP microprocessor detects this signal, it will trigger the corresponding interrupt processing program to accurately obtain the starting time of the circuit breaker opening and closing cycle.

[0056] As one of the preferred solutions, the sampling resistor is used to convert the current signal of the Hall current sensor into a voltage signal, and the Schmitt trigger gate circuit chip is used to preprocess the voltage signal, and the preprocessing includes shaping and noise filtering.

[0057] After receiving the signal, the DSP microprocessor triggers the sending of the high-frequency signal and enables the CAP capture port. The DSP microprocessor generates a low-voltage high-frequency signal and superimposes it on the high-voltage power frequency AC signal at one end of the circuit breaker's moving and static contacts through a high-frequency signal coupling circuit. At the other end of the corresponding phase, the high-frequency signal decoupling circuit decouples the low-voltage high-frequency signal from the high-voltage power frequency AC signal.

[0058] Specifically, see Figure 3 , Figure 3A schematic diagram of a high-frequency signal coupling circuit in one embodiment of the present application is shown. As the output source of the high-frequency signal, the DSP outputs a high-frequency pulse signal through the GPIOA0 pin. The optoelectronic isolator is located between the DSP output and the high-frequency coupling transformer, and is used to achieve electrical isolation to prevent the voltage or current on the high-voltage side from damaging the DSP. The high-frequency coupling transformer T1 is the core component in the circuit, which realizes the electromagnetic coupling of the high-frequency signal between the primary coil (low-voltage side) and the secondary coil (high-voltage side). At the same time, due to the isolation effect of the transformer, the power frequency voltage on the high-voltage side can be effectively prevented from being transmitted to the low-voltage side.

[0059] C1 is located between the secondary coil of the high-frequency coupling transformer and the static contact of the high-voltage circuit breaker, and is used to couple the high-frequency signal to the high-voltage power frequency AC. At the same time, C1 also has the function of preventing the high-voltage power frequency voltage from being transmitted to the secondary coil of the high-frequency coupling transformer. In order to prevent the high-frequency signal from attenuating during transmission, a DC power supply of appropriate size can be added to the output end of the optocoupler chip for signal amplification. In this circuit, a +5V DC power supply is used. Inductor L1 is located on the secondary line terminal of the high-frequency coupling circuit, and is used to prevent the high-frequency signal from flowing into the ground, ensuring the integrity and stability of the signal.

[0060] As one of the preferred solutions, the high-frequency signal coupling circuit includes an optoelectronic isolator, a high-voltage side loop, a high-frequency coupling transformer and a low-voltage side loop. The input end of the optoelectronic isolator is connected to the DSP microprocessor, the output end of the optoelectronic isolator is connected to the high-voltage side loop, and the high-voltage side loop is connected to the low-voltage side loop through a high-frequency coupling transformer.

[0061] As one of the preferred solutions, the photoelectric isolator is used to isolate the low-voltage high-frequency signal sent by the DSP microprocessor from the high-voltage side circuit in the high-frequency signal coupling circuit;

[0062] The high-frequency coupling transformer is used to isolate the high-voltage side circuit from the low-voltage side circuit in the high-frequency signal coupling circuit.

[0063] DSP outputs a high-frequency pulse signal through the GPIOA0 pin. After being electrically isolated by the optoelectronic isolator, the signal is transmitted to the primary coil of the high-frequency coupling transformer. The high-frequency coupling transformer T1 uses the principle of electromagnetic induction to couple the high-frequency signal on the primary coil to the secondary coil. Due to the isolation effect of the transformer, electrical isolation is achieved between the primary coil and the secondary coil.

[0064] As one of the preferred solutions, the low-voltage side loop includes a first inductor and a high-voltage power coupling capacitor, and the first inductor is used to transmit the low-voltage high-frequency signal in the low-voltage side loop along a preset path;

[0065] High-voltage power coupling capacitors are used to couple low-voltage high-frequency signals to the high-voltage power frequency alternating current at one end of the moving and static contacts of the target circuit breaker.

[0066] Inductor L1 is located on the secondary line terminal to prevent high-frequency signals from flowing into the ground, ensuring signal integrity and stability. At the same time, the entire circuit uses two-level isolation (photoelectric isolation and high-frequency transformer isolation) to prevent high-voltage signals from being transmitted to the low-voltage end and causing possible damage to equipment or personnel.

[0067] As one of the preferred solutions, the high-voltage side circuit includes a DC power supply, and the DC power supply is used to amplify the low-voltage and high-frequency signal.

[0068] The high-frequency signal on the secondary coil is coupled to the high-voltage power frequency AC power after passing through the high-voltage power coupling capacitor C1. At the same time, C1 prevents the high-voltage power frequency voltage from being transmitted to the secondary coil of the high-frequency coupling transformer. In order to enhance the signal transmission effect, a +5V DC power supply can be added to the output end of the optocoupler chip for signal amplification.

[0069] As one of the preferred solutions, a bidirectional diode is provided between the first inductor and the high-voltage power coupling capacitor, and the bidirectional diode is used to protect the high-frequency signal coupling circuit.

[0070] The main function of the high-frequency signal decoupling circuit is to decouple the high-frequency signal coupled to a certain phase of the static contact of the circuit breaker from the high-voltage power frequency signal at the moving contact end of the high-voltage circuit breaker, and transmit it safely and effectively to the capture unit of the DSP for processing. For details, please refer to Figure 4 , Figure 4 Shown is a schematic diagram of a high-frequency signal decoupling circuit in one embodiment of the present application.

[0071] As one preferred solution, the high-frequency signal decoupling circuit includes a power decoupling capacitor, a high-frequency isolation transformer, a second inductor and an optical coupling chip, wherein:

[0072] The power decoupling capacitor is used to decouple the low-voltage high-frequency signal from the other end of the moving and static contacts of the target circuit breaker;

[0073] The second inductor is used for transmitting the low-voltage high-frequency signal along a preset path;

[0074] The high-frequency isolation transformer is used to transmit the decoupled low-voltage high-frequency signal from the high-voltage end of the high-frequency signal decoupling circuit to the low-voltage end;

[0075] Optocoupler chips are used to electrically isolate and level-convert low-voltage and high-frequency signals at the low-voltage end.

[0076] Among them, the power decoupling capacitor C2 is installed at the other end of the high-frequency signal coupling circuit connection phase (i.e., the moving contact end). Its key function is to separate the high-frequency signal from the mixed high-voltage power frequency signal. C2 allows high-frequency signals to pass through, while blocking the transmission of high-voltage power frequency signals (low-frequency signals). The high-frequency isolation transformer T2 is a key isolation and transmission element. Its primary coil is connected to C2 to receive the high-frequency signal decoupled from the high-voltage side. T2 uses the principle of electromagnetic induction to transmit the high-frequency signal on the primary coil to the secondary coil, while achieving electrical isolation between high and low voltages.

[0077] Inductor L2 is connected to the other end of the primary coil of the high-frequency isolation transformer T2, and provides a return path for the high-frequency signal through grounding. The main function of L2 is to prevent the high-frequency signal from flowing into the ground to ensure the integrity and stability of the signal. The optocoupler chip is located at the output end of the secondary coil of the high-frequency isolation transformer T2, and is used to achieve electrical isolation and level conversion. The optocoupler chip converts the high-frequency signal from the high-voltage side to a level that can be recognized by the DSP on the low-voltage side, while providing an additional electrical isolation layer to ensure the safe operation of the DSP.

[0078] Specifically, at the moving contact end of the high-voltage circuit breaker, the power decoupling capacitor C2 separates the high-frequency signal from the mixed high-voltage power frequency signal. The capacitance characteristics of C2 allow high-frequency signals to pass through, while preventing the transmission of high-voltage power frequency signals. The decoupled high-frequency signal is transmitted to the secondary coil through the primary coil of the high-frequency isolation transformer T2. T2 uses the principle of electromagnetic induction to achieve signal transmission and simultaneously provides electrical isolation between high and low voltages. The high-frequency signal output by the secondary coil of the high-frequency isolation transformer T2 is electrically isolated and level-converted by the optocoupler chip. The optocoupler chip converts the signal from the high-voltage side to a level that can be recognized by the DSP on the low-voltage side, while providing an additional electrical isolation layer. The high-frequency signal after electrical isolation and level conversion is transmitted to the DSP capture unit, and the DSP captures, processes and analyzes the signal to achieve corresponding functions and controls.

[0079] As one of the preferred solutions, the LCD display interface, the alarm module and the communication module are connected to the DSP microprocessor respectively, wherein:

[0080] The LCD display interface is used to display the monitoring data analyzed by the DSP microprocessor;

[0081] The alarm module is used to perform alarm processing when the monitoring data reaches the preset conditions;

[0082] The communication module is used to upload monitoring data to the data center.

[0083] Specifically, the LCD display interface is used to intuitively display various information of the monitoring system, including but not limited to the number of opening and closing times, time intervals, historical records, current status (closing / opening) of the target circuit breaker, and possible fault alarm information, etc. It provides a user-friendly interface so that operation and maintenance personnel can quickly understand the operating status of the equipment, facilitating maintenance and troubleshooting.

[0084] The alarm module is also connected to the DSP microprocessor. When the data analyzed and processed by the DSP microprocessor reaches the preset alarm conditions (such as abnormally frequent opening and closing times, time intervals outside the normal range, etc.), the alarm module will be activated. The alarm module can include an audible and visual alarm device to alert the operation and maintenance personnel by emitting sound and / or light signals to ensure timely response measures to prevent potential equipment failures or safety accidents.

[0085] The communication module is responsible for uploading the monitoring data (such as opening and closing cycle records, fault alarm information, etc.) processed by the DSP microprocessor to the remote monitoring system or data center. This helps to achieve remote monitoring and management of equipment and improve operation and maintenance efficiency. At the same time, the communication module also supports receiving control instructions from the remote system to achieve remote configuration and adjustment of the monitoring system.

[0086] Figure 5 The figure shows a schematic diagram of the external interrupt 1 processing program in one embodiment of the present application. The external interrupt 1 processing program mainly completes the timing of the start point of the circuit breaker opening cycle. When the circuit breaker opening circuit is energized, the Hall current sensor will capture this moment and generate an edge level signal through its output conditioning circuit. This signal triggers the external interrupt 1, causing the microprocessor to start sending high-frequency signals and start the capture unit to count pulses.

[0087] The trigger signal of external interrupt 1 is the moment when the trip circuit is energized, obtained by the Hall current sensor. The Hall current sensor has a fast response characteristic (microsecond level), and can accurately capture the moment when the trip coil is energized, that is, the start of the trip cycle. After the signal is shaped and filtered by the output conditioning circuit, it provides a standard edge trigger signal for the external interrupt of the microprocessor. The following is the specific processing flow:

[0088] 1) When the Hall current sensor detects that the opening circuit is energized, the output conditioning circuit generates an edge level signal;

[0089] 2) This signal triggers external interrupt 1, and the microprocessor enters the interrupt handling routine;

[0090] 3) In the interrupt processing program, the microprocessor sends a high-frequency signal and starts the capture units CAP1, CAP2, and CAP3 to count pulses;

[0091] 4) The capture unit records the opening time T of phase A, phase B, and phase C respectively fa , T fb , T fc ;

[0092] 5) According to the definition of time parameters in opening and closing in GB 1984-2014, the opening cycle is calculated as T fa , T fb , T fc The maximum value of

[0093] 6) Simultaneously calculate the three phases at different times, i.e. T fa , T fb , T fc The difference between the maximum and minimum values ​​of .

[0094] Through the external interrupt 1 processing program, the starting point of the circuit breaker's opening cycle can be accurately captured, and the opening cycle and the three-phase phase difference can be calculated, providing important parameters for the stable operation of the power system.

[0095] Figure 6 The figure shows a schematic flow chart of the external interrupt 2 processing program in one embodiment of the present application. The external interrupt 2 processing program mainly completes the timing of the starting point of the circuit breaker closing cycle. When the circuit breaker closing circuit is energized, the Hall current sensor will capture this moment and generate an edge level signal through its output conditioning circuit. This signal triggers external interrupt 2, causing the microprocessor to start emitting a high-frequency signal and start the timer for timing. At the same time, the capture interrupt is enabled, and the timer timing is stopped when the capture unit captures the first pulse.

[0096] The trigger signal of external interrupt 2 is the moment when the closing circuit is energized, obtained by the Hall current sensor. Similar to the opening cycle, the Hall current sensor can accurately capture the moment when the closing coil is energized, that is, the start of the closing cycle. This signal is also shaped and filtered by the output conditioning circuit to provide a standard edge trigger signal for the external interrupt of the microprocessor. The following is the specific processing flow:

[0097] 1) When the Hall current sensor detects that the closing circuit is energized, the output conditioning circuit generates an edge level signal;

[0098] 2) This signal triggers external interrupt 2, and the microprocessor enters the interrupt handling routine;

[0099] 3) In the interrupt handler, the microprocessor sends a high-frequency signal and starts the timer for timing;

[0100] 4) At the same time, the capture interrupt is enabled, and the capture unit waits to capture the high-frequency signal;

[0101] 5) When the capture unit captures the first pulse, the timer stops timing;

[0102] 6) Record the closing time T of phase A, phase B, and phase C ha , T hb , T hc ;

[0103] 7) The frequency signal acquisition program completes the signal frequency acquisition calculation and the corresponding relationship processing between the frequency signal and the opening and closing cycle.

[0104] Through the external interrupt 2 processing program, the starting point of the circuit breaker closing cycle can be accurately captured and the closing time can be calculated. At the same time, combined with the frequency signal acquisition program, the corresponding relationship between the frequency signal and the opening and closing cycle can be further analyzed, providing an important basis for the stable operation and fault troubleshooting of the power system.

[0105] In summary, the external interrupt 1 and external interrupt 2 handlers play an important role in the power system. They can accurately capture the starting point of the opening and closing cycle of the circuit breaker and calculate the relevant parameters, providing strong support for the stable operation of the power system.

[0106] Compared with the prior art, the beneficial effects of the embodiments of the present application are at least one of the following:

[0107] 1) The system of the present application can monitor key parameters such as the opening and closing cycle of the circuit breaker in real time, detect and handle potential faults in a timely manner, and improve the stability and reliability of the power system.

[0108] 2) The application of Hall current sensor and high-frequency signal coupling and decoupling circuit enables the system to measure the current and voltage signals of the circuit breaker with high precision, improving the accuracy and reliability of the data.

[0109] 3) The DSP microprocessor unit can perform intelligent analysis and diagnosis based on the real-time monitored data, accurately determine the status of the circuit breaker, and avoid the errors and uncertainties of manual judgment.

[0110] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A circuit breaker opening and closing cycle monitoring system, characterized in that: include: Hall current sensor, output signal conditioning circuit, high frequency signal coupling circuit, high frequency signal decoupling circuit, DSP microprocessor, LCD display interface, alarm module and communication module, among which, One end of the Hall current sensor is connected to the opening and closing coil of the target circuit breaker, and is used to send the sensed current signal of the opening and closing coil of the target circuit breaker to the output signal conditioning circuit; The output end of the output signal conditioning circuit is connected to the signal receiving end of the DSP microprocessor, and is used to receive the current signal output by the Hall current sensor, and convert and condition the current signal, and send the voltage signal obtained after conditioning to the DSP microprocessor; The input end of the high-frequency signal coupling circuit is connected to the signal output end of the DSP microprocessor, and is used to receive the low-voltage high-frequency signal generated by the DSP microprocessor, and couple the low-voltage high-frequency signal to the high-voltage power frequency AC signal at one end of the moving and static contacts of the target circuit breaker; The output end of the high-frequency signal decoupling circuit is connected to the signal capture end of the DSP microprocessor, and is used to decouple the low-voltage high-frequency signal from the high-voltage power frequency AC signal at the other end of the moving and static contacts of the target circuit breaker, and transmit the low-voltage high-frequency signal to the DSP microprocessor; The DSP microprocessor is used to send the low-voltage high-frequency signal to the high-frequency signal coupling circuit after receiving the voltage signal, and simultaneously receive the low-voltage high-frequency signal sent by the high-frequency signal decoupling circuit.

2. The circuit breaker opening and closing cycle monitoring system according to claim 1, characterized in that: The output signal conditioning circuit includes a sampling resistor and a Schmitt trigger gate circuit chip, one end of the sampling resistor is connected to the output end of the Hall current sensor, the other end of the sampling resistor is connected to the input end of the Schmitt trigger gate circuit chip, and the output end of the Schmitt trigger gate circuit chip is connected to the DSP microprocessor unit.

3. The circuit breaker opening and closing cycle monitoring system according to claim 2, characterized in that: The sampling resistor is used to convert the current signal of the Hall current sensor into a voltage signal, and the Schmitt trigger gate circuit chip is used to pre-process the voltage signal, wherein the pre-processing includes shaping and noise filtering.

4. The circuit breaker opening and closing cycle monitoring system according to claim 1, characterized in that: The high-frequency signal coupling circuit includes a photoelectric isolator, a high-voltage side loop, a high-frequency coupling transformer and a low-voltage side loop. The input end of the photoelectric isolator is connected to the DSP microprocessor, the output end of the photoelectric isolator is connected to the high-voltage side loop, and the high-voltage side loop is connected to the low-voltage side loop through the high-frequency coupling transformer.

5. The circuit breaker opening and closing cycle monitoring system according to claim 4, characterized in that: The photoelectric isolator is used to isolate the low-voltage high-frequency signal sent by the DSP microprocessor from the high-voltage side circuit in the high-frequency signal coupling circuit; The high-frequency coupling transformer is used to isolate the high-voltage side circuit from the low-voltage side circuit in the high-frequency signal coupling circuit.

6. The circuit breaker opening and closing cycle monitoring system according to claim 4, characterized in that: The high-voltage side loop includes a DC power supply, and the DC power supply is used to amplify the low-voltage high-frequency signal.

7. The circuit breaker opening and closing cycle monitoring system according to claim 4, characterized in that: The low-voltage side loop includes a first inductor and a high-voltage power coupling capacitor, wherein the first inductor is used to transmit the low-voltage high-frequency signal in the low-voltage side loop along a preset path; The high-voltage power coupling capacitor is used to couple the low-voltage high-frequency signal to the high-voltage power frequency alternating current at one end of the moving and static contacts of the target circuit breaker.

8. The circuit breaker opening and closing cycle monitoring system according to claim 7, characterized in that: A bidirectional diode is provided between the first inductor and the high-voltage power coupling capacitor, and the bidirectional diode is used to protect the high-frequency signal coupling circuit.

9. The circuit breaker opening and closing cycle monitoring system according to claim 1, characterized in that: The high-frequency signal decoupling circuit includes a power decoupling capacitor, a high-frequency isolation transformer, a second inductor and an optical coupling chip, wherein: The power decoupling capacitor is used to decouple the low-voltage high-frequency signal from the other end of the moving and static contacts of the target circuit breaker; The second inductor is used for transmitting the low-voltage high-frequency signal along a preset path; The high-frequency isolation transformer is used to transmit the low-voltage high-frequency signal obtained by decoupling from the high-voltage end of the high-frequency signal decoupling circuit to the low-voltage end; The optical coupling chip is used to perform electrical isolation and level conversion on the low-voltage high-frequency signal at the low-voltage end.

10. The circuit breaker opening and closing cycle monitoring system according to claim 1, characterized in that: The liquid crystal display interface, the alarm module and the communication module are connected to the DSP microprocessor respectively, wherein: The liquid crystal display interface is used to display the monitoring data analyzed by the DSP microprocessor; The alarm module is used to perform alarm processing when the monitoring data reaches a preset condition; The communication module is used to upload the monitoring data to a data center.

Images