L-type high-speed electronic circuit breaker intelligent protector

Abstract

This invention discloses an L-type high-speed electronic circuit breaker intelligent protector, comprising a three-channel T-type bidirectional electronic switch, an LC low-pass filter, a relay output channel, a current detection channel, and a main control module. The three-channel T-type bidirectional electronic switch includes three silicon carbide switch groups K3. The first silicon carbide switch group K1 is electrically connected to the input power supply. The output terminals of the first silicon carbide switch group K1 are electrically connected to the second silicon carbide switch group K2 and the third silicon carbide switch group K3, respectively. The second silicon carbide switch group K2 and the third silicon carbide switch group K3 are electrically connected to the relay output channel, respectively. This invention utilizes a silicon carbide MOS common-drain connection method, combining single-phase electronic switches into a bidirectional electronic switch, and incorporates a DC BUCK-BOOST method, enabling the intelligent protector to operate on both AC and DC power supplies. This eliminates short-circuit sparks during short circuits, effectively preventing fire accidents caused by short circuits.

Description

Technical Field

[0001] This invention relates to the field of electronic circuit breakers, and in particular to an L-type high-speed electronic circuit breaker intelligent protector. Background Technology

[0002] Electrical short circuits or equipment malfunctions are the main culprits behind electrical fires. The dangers of electrical fires to human life and property are countless. Now, with the production of new energy vehicles, the electricity load in urban communities is increasing, and every year, aging wiring and excessive load cause severe overheating. Summer, with its high ambient temperatures, is a peak season for electrical fires. Most ordinary household or commercial electrical systems only have a single residual current device (RCD) and multiple 1P circuit breakers. This method only provides basic protection, and sparks can still occur in the event of a short circuit.

[0003] Traditional mechanical circuit breakers use electromagnetic tripping to protect equipment from damage caused by short circuits. However, the biggest drawback of this method is its slow response and insensitive reaction. Furthermore, the hysteresis effect of the electromagnetic tripping device, combined with the reaction of mechanical components, results in an operating time of 30 milliseconds (ms) or even longer. Since the energy of a short-circuit spark is proportional to the current multiplied by time, a short circuit in the output line of a mechanical circuit breaker will generate a very large spark, which can easily ignite flammable materials and gases. Additionally, mechanical circuit breakers use bimetallic reeds for overcurrent and overload protection. The speed and duration of the reed's response are unpredictable under different ambient temperatures. It operates much slower at low temperatures than at high temperatures. Therefore, in some cases where the equipment and lines downstream of the circuit breaker are severely overheated, the bimetallic reed may not even trip. Moreover, bimetallic reeds are also subject to the risk of metal fatigue. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an L-type high-speed electronic circuit breaker intelligent protector.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] An L-type high-speed electronic circuit breaker intelligent protector includes: a three-channel T-type bidirectional electronic switch, an LC low-pass filter, a relay output channel, a current detection channel, and a main control module.

[0007] The input terminal of the three-channel T-type bidirectional electronic switch is electrically connected to the input power supply. The three-channel T-type bidirectional electronic switch is electrically connected to the main control module. The output terminal of the three-channel T-type bidirectional electronic switch is electrically connected to the relay output channel. The output terminal of the relay output channel outputs voltage through the LC low-pass filter and the current detection channel.

[0008] The three-channel T-type bidirectional electronic switch includes a first silicon carbide switch group K1, a second silicon carbide switch group K2, and a third silicon carbide switch group K3. The input terminal of the first silicon carbide switch group K1 is electrically connected to the input power supply. The output terminal of the first silicon carbide switch group K1 is electrically connected to the input terminals of the second silicon carbide switch group K2 and the third silicon carbide switch group K3, respectively. The output terminals of the second silicon carbide switch group K2 and the third silicon carbide switch group K3 are electrically connected to the input terminal of the relay output channel, respectively.

[0009] In one embodiment, a fault arc detection unit is further included. The input terminal of the fault arc detection unit is electrically connected to the output terminal of the current detection channel, the output terminal of the fault arc detection unit is electrically connected to the main control module, and the output terminal of the fault arc detection unit is used to output voltage.

[0010] In one embodiment, a PWM drive generator is also included, which is electrically connected to the three-channel T-type bidirectional electronic switch and the main control module, respectively.

[0011] In one embodiment, the main control module is an MCU processor or a DSP processor.

[0012] In one embodiment, the three-channel T-type bidirectional electronic switch further includes a connecting inductor L, the first end of which is electrically connected to the output terminal of the first silicon carbide switch group K1, and the second end of which is electrically connected to the input terminal of the third silicon carbide switch group K3.

[0013] In one embodiment, the current detection channel includes a main current detection unit and a leakage current detection unit. The input terminal of the main current detection unit is electrically connected to the output terminal of the LC low-pass filter, and the output terminal of the main current detection unit is electrically connected to the leakage current detection unit. The output terminal of the leakage current detection unit is used to output voltage.

[0014] In one embodiment, the current detection channel further includes an output voltage detection unit, which is electrically connected to the output terminal of the leakage current detection unit, and the output terminal of the output voltage detection unit is electrically connected to the output terminal of the fault arc detection unit.

[0015] In one embodiment, a waveform correction unit is further included. The two input terminals of the waveform correction unit are electrically connected to the output terminals of the leakage current detection unit and the fault arc detection unit, respectively, and the output terminal of the waveform correction unit is electrically connected to the main control module.

[0016] In one embodiment, it further includes three RC snubber channels, the input of each of the RC snubber channels being electrically connected to the first silicon carbide switch group K1, the second silicon carbide switch group K2, and the third silicon carbide switch group K3, respectively.

[0017] In one embodiment, the system further includes a combustible gas detection unit, a temperature detection unit, a voltage and current detection unit, and a communication unit, which are electrically connected to the main control module.

[0018] The advantages and beneficial effects of this invention compared to the prior art are as follows:

[0019] This invention is an L-shaped high-speed electronic circuit breaker intelligent protector. It employs a silicon carbide MOS common-drain connection, combining single-phase electronic switches into a bidirectional electronic switch, and incorporates a DC BUCK-BOOST mechanism, enabling the intelligent protector to operate on both AC and DC power supplies. Three sets of electronic switches, combined with an inductor, form two back-to-back L-shaped configurations, eliminating short-circuit sparks in the circuit breaker's output line during short circuits. This effectively prevents fires caused by short circuits in electrical circuits or loads. The rail-to-rail leakage current following technology can rapidly dissipate residual current in the line, even when there is no leakage or leakage exists. When a person accidentally touches a live conductor, the three-stage bidirectional electronic switch discharges the current in the line at a speed of nanoseconds (NS), resulting in an extremely slight electric shock sensation, similar to the voltage released by a lighter, thus ensuring personal safety. Combined with power metering and information communication, it can transmit data from the line to a platform in real time. Attached Figure Description

[0020] Figure 1 This is a functional principle diagram of an L-type high-speed electronic circuit breaker intelligent protector according to one embodiment of the present invention.

[0021] Figure 2 This is a functional schematic diagram of a traditional circuit breaker.

[0022] Figure 3 This is a functional schematic diagram of a traditional circuit breaker.

[0023] Figure 4 for Figure 1 The circuit diagram of the L-type high-speed electronic circuit breaker intelligent protector is shown below.

[0024] Figure 5 for Figure 1 Functional principle diagram of an L-type high-speed electronic circuit breaker intelligent protector according to one embodiment;

[0025] Figure 6 for Figure 1 Circuit diagram of another embodiment of the L-type high-speed electronic circuit breaker intelligent protector;

[0026] Figure 7 for Figure 1 Circuit diagram of an L-type high-speed electronic circuit breaker intelligent protector according to another embodiment;

[0027] Figure 8 for Figure 1 The voltage curve of the L-shaped high-speed electronic circuit breaker intelligent protector is shown below.

[0028] Figure 9 for Figure 1 The circuit diagram shown is of the L-type high-speed electronic circuit breaker intelligent protector during waveform correction.

[0029] Figure 10 for Figure 9 The waveform diagram of the intelligent protector during waveform correction is shown below.

[0030] Figure 11 Waveforms for short-circuit current detection and fault arc acquisition;

[0031] Figure 12 This is a driving waveform diagram of an L-type high-speed electronic circuit breaker intelligent protector according to an embodiment of the present invention;

[0032] Figure 13 for Figure 1 The diagram shows the auxiliary power supply circuit of the L-shaped high-speed electronic circuit breaker intelligent protector.

[0033] Figure 14 for Figure 1 The circuit diagram of the magnetic latching relay of the L-type high-speed electronic circuit breaker intelligent protector is shown below;

[0034] Figure 15 The circuit diagram of the isolated driving optocoupler of the present invention is shown below;

[0035] Figure 16 This is a circuit diagram of the modulation pulse generator of the present invention;

[0036] Figure 17 This is a circuit diagram of the relay control section of the present invention;

[0037] Figure 18 for Figure 1 The circuit diagram of the current-controlled lock is shown below;

[0038] Figure 19 for Figure 1 The circuit diagram for the leakage current detection section is shown below.

[0039] Figure 20 for Figure 1 The circuit diagram of the AND gate circuit is shown below;

[0040] Figure 21 for Figure 1 The circuit diagram shown is for the analog output of main current and leakage current.

[0041] Figure 22 for Figure 1 The circuit diagram of the voltage acquisition section is shown below;

[0042] Figure 23 for Figure 1 The circuit diagram of the MCU processor shown is shown.

[0043] Figure 24 for Figure 1 The circuit diagram of the communication section is shown below;

[0044] Figure 25 for Figure 1 The circuit diagram of the 4G communication section is shown below;

[0045] Figure 26 for Figure 1 The circuit diagram of the network connection section is shown;

[0046] Figure 27 This is a functional principle diagram of an L-type high-speed electronic circuit breaker intelligent protector according to one embodiment of the present invention. Detailed Implementation

[0047] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0048] This is a new type of smart protector that iterates and updates upon the traditional MOS-type electronic circuit breaker and IGBT-type electronic circuit breaker I-type architecture smart protector. Traditional MOS-type electronic circuit breakers and IGBT-type electronic circuit breakers both adopt the I-type structure. This type of electronic circuit breaker simply connects the unidirectional MOS transistor and IGBT transistor back to back to form an electronic switch, using the principle of high-speed turn-off of the electronic switch for protection. However, it cannot eliminate the residual current in the circuit, which can still cause a large short-circuit spark. There are also more advanced ones that use a single-stage L-type architecture, but this architecture cannot perform voltage boost control, which is not possible in some environments where voltage boosting is required.

[0049] Traditional electronic circuit breakers use silicon MOSFETs or IGBTs. While MOSFETs have high switching frequencies, their drawback is that they cannot achieve high voltages; the highest voltage cannot reach 800V. Although IGBTs have high voltage ratings, their internal PN junction structure prevents electrons from flowing bidirectionally. In the reverse direction, electrons can only flow through the IGBT's internal diode, resulting in very high losses. For every 100A increase in current, losses increase by 190-300W.

[0050] The L-type high-speed electronic circuit breaker intelligent protector of this application uses low internal resistance silicon carbide MOS as the carrier. Its internal resistance is only 40MΩ (milliohms) or even lower, so its loss is extremely small. When used as an electronic switch, it is equivalent to a direct circuit. At the same time, silicon carbide MOS has extremely high withstand voltage and is not a PN junction architecture, so its frequency response speed is excellent. By utilizing these advantages and adding a double L-type circuit design, it not only realizes the function of traditional electronic circuit breakers, but also further optimizes the function of eliminating short-circuit sparks.

[0051] Please see Figure 2 In the traditional method, the power supply passes through the circuit breaker Q1 to the IGBT bidirectional electronic switch K1, and then to the relay switch KM1 for physical isolation. After that, it enters the main current detection CT1 to collect and compare the current. This method cannot adjust the output voltage, and there is no secondary electronic switch to discharge the residual current in the circuit. Although it can effectively suppress short-circuit sparks, the effect is relatively poor. In addition, the IGBT switch is composed of PN junctions, so the resulting on-state voltage drop is relatively large and the loss is relatively high.

[0052] Please see Figure 3 In another traditional approach, the power supply enters the inductors L1 / L2 / L3 after passing through bidirectional switches K1 / K2 / K3, with bidirectional switches K4 / K5 / K6 serving as freewheeling paths. Although this method allows for short-circuit arc suppression, it lacks a single-stage architecture and cannot implement a boost function, only a BUCK function. Furthermore, this method restricts current operation to CCM and DCM modes, resulting in high losses and heat generation due to the high-speed electronic switching. CCM and DCM are commonly used terms in switching power supplies, referring to the inductor current operating mode. CCM stands for Continuous Conduction Mode, while DCM stands for Discontinuous Conduction Mode.

[0053] The L-type high-speed electronic circuit breaker intelligent protector of the present invention is a new type of power protection device derived from the technology of electronic circuit breakers. It replaces the traditional IGBT electronic circuit breaker and adopts a more advanced silicon carbide MOS. Traditional silicon MOS or IGBT electronic circuit breakers can only realize bidirectional switching function and cannot eliminate short-circuit sparks caused by residual charge in the line. The L-type electronic circuit breaker can only realize the functions of voltage reduction and bidirectional electronic switching.

[0054] The L-type high-speed electronic circuit breaker intelligent protector uses silicon carbide high-speed MOSFETs to replace mechanical contacts, thus eliminating the sparking problem caused by switching contacts. Furthermore, the high-speed MOSFETs have extremely fast switching speeds, on the order of nanoseconds, allowing for rapid shutdown of the output when a short circuit occurs in the circuit or load. It finds wide application in environments with dust, flammable gases, flammable liquids, mines, smelting plants, and manufacturing facilities, where electrical circuits or equipment are highly sensitive to sparks; even a small spark can have catastrophic consequences.

[0055] The L-type high-speed electronic current-breaking intelligent protector can be used in any secondary protection electrical environment. Connected to the output of a secondary switch, it is suitable for homes, shopping malls, office buildings, schools, hospitals, shops, banks, government agencies, institutions, scenic spots, and many other areas requiring protection. It is particularly useful in hospitals, especially psychiatric hospitals, where patients, lacking basic awareness, may inadvertently touch electrical outlets with metal objects, posing a risk of electric shock. The L-type high-speed electronic current-breaking intelligent protector's rail-to-rail leakage protection reacts within 100 nanoseconds (ns), disconnecting the output and discharging the current in the line to protect personal safety. In mining applications, such as coal mines where low or high voltage is required, the L-type high-speed electronic current-breaking intelligent protector can act as a steplessly adjustable transformer, continuously adjusting the output voltage within the required variable voltage range.

[0056] In the new energy field, the L-type high-speed electronic circuit breaker can act as a contactless electronic switch. In photovoltaic, energy storage, and charging applications, since direct current has no zero point, the energy storage battery experiences arcing when its output is cut off while it is still providing current. The intensity of this arcing varies with the voltage and current; the higher the voltage and the greater the current, the longer and stronger the arc. Traditional DC circuit breakers and vacuum switches are bulky, expensive, and have short lifespans. The L-type high-speed electronic circuit breaker uses a 1600V silicon carbide MOSFET. Instead of mechanical contacts, it uses an electric field channel, enabling it to operate in a 1600V voltage environment and achieve its protective function.

[0057] Specifically, please refer to Figure 1This document describes an L-type high-speed electronic circuit breaker intelligent protector, hereinafter referred to as "intelligent protector." Specifically, the L-type high-speed electronic circuit breaker intelligent protector includes: a three-channel T-type bidirectional electronic switch, an LC low-pass filter, a relay output channel, a current detection channel, and a main control module. Preferably, the main control module is an MCU processor or a DSP processor. It should be noted that the main control module sends control signals to the three-channel T-type bidirectional electronic switch based on the real-time monitored power system status. The silicon carbide switch group, with its high-speed switching characteristics, can quickly respond to the instructions of the main control module, achieving rapid on / off control of the circuit. This design enables the protector to cut off the circuit in a very short time when facing faults such as overcurrent and short circuits, effectively preventing the fault from escalating and protecting the safety of power equipment. When current flows out from the relay output channel, it passes through the LC low-pass filter. The LC low-pass filter utilizes the energy storage characteristics of inductance and capacitance to filter out high-frequency noise and interference signals in the circuit, allowing only low-frequency effective signals to pass. This process significantly improves the quality of the output voltage, reduces system malfunctions caused by noise interference, and provides a stable and reliable signal source for subsequent current detection and fault diagnosis. The relay output channel, as a key component in circuit switching, achieves circuit connection and disconnection under the control of a three-channel T-type bidirectional electronic switch. Simultaneously, it provides a stable current transmission channel for subsequent filtering and detection stages, ensuring the normal operation of the entire protection system. The current detection channel monitors the filtered current signal in real time and converts the detected current information into an electrical signal, transmitting it to the main control module and the fault arc detection unit. Based on the received current information, the main control module performs real-time analysis and judgment of the power system's operating status, thereby making corresponding control decisions.

[0058] The input terminal of the three-channel T-type bidirectional electronic switch is electrically connected to the input power supply. The three-channel T-type bidirectional electronic switch is electrically connected to the main control module. The output terminal of the three-channel T-type bidirectional electronic switch is electrically connected to the relay output channel. The output terminal of the relay output channel outputs voltage through the LC low-pass filter and the current detection channel.

[0059] The three-channel T-type bidirectional electronic switch includes a first silicon carbide switch group K1, a second silicon carbide switch group K2, and a third silicon carbide switch group K3. The input terminal of the first silicon carbide switch group K1 is electrically connected to the input power supply. The output terminal of the first silicon carbide switch group K1 is electrically connected to the input terminals of the second silicon carbide switch group K2 and the third silicon carbide switch group K3, respectively. The output terminals of the second silicon carbide switch group K2 and the third silicon carbide switch group K3 are electrically connected to the input terminal of the relay output channel, respectively.

[0060] The L-shaped high-speed electronic circuit breaker intelligent protector also includes a fault arc detection unit. The input terminal of the fault arc detection unit is electrically connected to the output terminal of the current detection channel, and the output terminal of the fault arc detection unit is electrically connected to the main control module. The output terminal of the fault arc detection unit is used to output voltage. It should be noted that the fault arc detection unit utilizes current information to detect the presence of a fault arc in the circuit. The fault arc detection unit uses the current information provided by the current detection channel to detect the presence of a fault arc in the circuit in real time. Once a fault arc is detected, the fault arc detection unit immediately sends an alarm signal to the main control module and simultaneously outputs a corresponding voltage signal, so that the main control module can take timely measures to cut off the circuit and prevent serious accidents such as fires caused by the fault arc.

[0061] Please see Figure 1 Power is supplied through circuit breaker Q1 to the first silicon carbide switch group K1. When voltage regulation is not required, silicon carbide switch groups K1 / K2 are operational, while the third silicon carbide switch group K3 remains closed. Current flows through silicon carbide switch groups K1 / K2 into the relay output channel. After high-frequency noise is filtered out by an LC low-pass filter composed of inductor L2 and capacitor C1, the current flows through the current output channel and then through the fault arc detection channel for output. When BUCK-BOOST mode is required, silicon carbide switch groups K1 / K2 enter PWM modulation mode, with the two silicon carbide switch groups providing complementary outputs. The duty cycle is adjusted from 10% to 90%, and the voltage is restored to the required output after high-frequency filtering by inductor L2 and capacitor C1.

[0062] The three-channel T-type bidirectional electronic switch also includes a connecting inductor L, the first end of which is electrically connected to the output terminal of the first silicon carbide switch group K1, and the second end of which is electrically connected to the input terminal of the third silicon carbide switch group K3.

[0063] Thus, by adopting a silicon carbide MOS common-drain connection, single-phase electronic switches are combined into bidirectional silicon carbide switch groups, and combined with DC BUCK-BOOST, the intelligent protector can operate on both AC and DC power supplies. The three silicon carbide switch groups are combined with an inductor to form two back-to-back L-type connections, thereby eliminating short-circuit sparks caused by short circuits in the circuit breaker output lines, effectively preventing fires caused by short circuits in electrical lines or loads. The rail-to-rail leakage current following technology can dissipate the residual current in the line at an extremely fast speed, even when there is no leakage or leakage in the line. When a person accidentally touches a live part, the three-stage bidirectional silicon carbide switch group discharges the current in the line at a speed of NS (nanosecond level). The electric shock sensation is extremely slight, like the voltage released by a lighter, thus achieving the purpose of personal safety. Combined with power metering and information communication, the data in the line can be sent to the platform in real time.

[0064] Please see Figure 27 The intelligent protector also includes a PWM drive generator, which is electrically connected to both the three-channel T-type bidirectional electronic switch and the main control module. It should be noted that the application of the PWM drive generator enables the three-channel T-type bidirectional electronic switch to operate with higher efficiency and precision. It can dynamically adjust the switching state based on real-time monitored power system parameters, effectively reducing energy loss and electromagnetic interference during the switching process. Furthermore, precise PWM control can improve circuit stability and reliability, reduce the probability of failure, and extend the service life of power equipment.

[0065] Please see Figure 27 The current detection channel includes a main current detection unit and a leakage current detection unit. The input terminal of the main current detection unit is electrically connected to the output terminal of the LC low-pass filter, and the output terminal of the main current detection unit is electrically connected to the leakage current detection unit. The output terminal of the leakage current detection unit is used to output voltage. It should be noted that by monitoring the main circuit current in real time, the main current detection unit can promptly detect obvious faults such as overcurrent and short circuits and quickly transmit the information to subsequent processing units. Its high-precision detection capability ensures accurate measurement of the main circuit current, providing a reliable basis for the protection device's operation and effectively preventing equipment damage and safety accidents caused by abnormal current. The leakage current detection unit can promptly detect potential leakage hazards, even when the leakage current is small, thereby triggering the corresponding actions of the protection device, such as cutting off the circuit and issuing an alarm. This greatly reduces the risk of electric shock accidents and electrical fires, improving the safety of the power system.

[0066] The current detection channel also includes an output voltage detection unit, which is electrically connected to the output terminal of the leakage current detection unit and to the output terminal of the fault arc detection unit. It should be noted that the output voltage detection unit can monitor voltage fluctuations in real time and promptly detect abnormal phenomena such as excessively high or low voltage. Through accurate detection of the output voltage, measures can be taken in advance to adjust circuit parameters, ensuring the normal operation of power equipment and avoiding equipment damage and performance degradation caused by abnormal voltage.

[0067] The L-shaped high-speed electronic circuit breaker intelligent protector also includes a waveform correction unit. The two input terminals of the waveform correction unit are electrically connected to the output terminals of the leakage current detection unit and the fault arc detection unit, respectively. The output terminal of the waveform correction unit is electrically connected to the main control module. It should be noted that the signals output by the leakage current detection unit and the fault arc detection unit may contain certain noise, distortion, or interference. After receiving these signals, the waveform correction unit uses advanced algorithms and filtering techniques to process and correct the signals in real time. The waveform correction unit can remove noise components from the signal, restore the true waveform of the signal, and transmit the corrected signal to the main control module. The waveform correction unit ensures that the signal received by the main control module is accurate and reliable, providing high-quality data support for subsequent fault diagnosis and control decisions.

[0068] The L-type high-speed electronic circuit breaker intelligent protector also includes three RC absorption channels. The input terminal of each RC absorption channel is electrically connected to the first silicon carbide switch group K1, the second silicon carbide switch group K2, and the third silicon carbide switch group K3, respectively. It should be noted that when the silicon carbide switch groups in the three-channel T-type bidirectional electronic switch perform high-speed switching operations, large voltage spikes and current surges are generated in the circuit. The RC absorption channels utilize the energy storage and buffering characteristics of resistors and capacitors to absorb the transient energy generated during the switching process. The capacitor stores energy at the moment the switch is turned on and releases energy at the moment the switch is turned off, thereby reducing the rate of change of voltage and current, reducing switching stress, and protecting the silicon carbide switch groups and other circuit components from damage.

[0069] Furthermore, the first silicon carbide switch group K1 includes two silicon carbide MOSFET switches connected in series, and a resistor-capacitor absorption channel connected across the two silicon carbide MOSFET switches. This reduces the rate of change of voltage and current, lowers switching stress, and protects the silicon carbide switch group and other circuit components from damage.

[0070] The L-shaped high-speed electronic circuit breaker intelligent protector also includes a combustible gas detection unit, a temperature detection unit, a voltage and current detection unit, and a communication unit, all of which are electrically connected to the main control module. It should be noted that the combustible gas detection unit monitors the concentration of combustible gas in the environment surrounding the protector in real time. When the detected combustible gas concentration exceeds a set safety threshold, it immediately sends an alarm signal to the main control module. Upon receiving the alarm signal, the main control module can take corresponding measures according to a preset program, such as cutting off the circuit or issuing audible and visual alarms, to prevent combustible gases from causing fires or explosions.

[0071] Power is supplied to a three-channel T-type bidirectional electronic switch and a PWM driver generator after passing through circuit breaker Q1. Upon detecting the power input, the required power type is input to the MCU or DSP for processing. An LC low-pass filter is connected after the three-channel T-type bidirectional electronic switch to filter out high-frequency signals at output. An RC snubber channel absorbs voltage and signal spikes caused by high-frequency switching. A relay output channel provides secondary physical isolation for the output voltage. The main current detection channel detects the main output current and load power, and analyzes short-circuit and overload signals. Leakage current detection detects residual and leakage current in the circuit. Output voltage detection provides real-time feedback of the required output voltage to the MCU. Fault arc detection checks for poor contact in the circuit and provides real-time feedback to the MCU.

[0072] The temperature detection unit monitors the temperature of the three-channel T-type bidirectional electronic switch in real time and adjusts the PWM duty cycle signal of the fan when the temperature is low. The PWM drive generator adjusts the duty cycle according to the input voltage and output voltage. The voltage and current detection unit monitors the input current and voltage and sends the feedback signal back to the MCU processing unit in real time. The MCU processing unit gives the PWM drive generator adjustment instructions as needed.

[0073] The combustible gas detection unit returns the combustible gas and smoke data values ​​in the circuit to the MCU processing unit. The MCU processing unit controls the output based on the collected values. The waveform correction unit returns the collected sine wave signal to the MCU processing unit. The communication unit returns the data collected by the machine to the big data platform in real time.

[0074] This is a single-unit three-unit BUCK-BOOST AC / DC universal step-up / step-down intelligent power protector made with silicon carbide (SiC) devices. It adopts a silicon carbide MOS common-drain connection method, and the single-phase electronic switches are combined into bidirectional silicon carbide switch groups. Combined with the DC BUCK-BOOST method, the intelligent protector can work in both AC and DC power supplies. The three bidirectional silicon carbide switch groups are combined with an inductor to form two back-to-back L-type configurations, hence the name L-type high-speed electronic interruption intelligent protector.

[0075] The L-type high-speed electronic circuit breaker is essentially a two-pole protector located below an air switch, circuit breaker, or residual current device. Its main function is to eliminate circuit breakers, prevent electrical fires, and protect personal safety and property. It adopts single-phase four-phase limited PWM dual-channel complementary pulse width modulation, combined with power metering, information communication, fault arc detection, combustible gas smoke collection, AC / DC step-up / step-down control, leakage and residual current collection, overload, overcurrent, overvoltage, and undervoltage control, making the L-type high-speed electronic circuit breaker intelligent protector no longer a simple electronic circuit breaker or mechanical circuit breaker. It fundamentally changes the working method of mechanical circuit breakers. Traditional mechanical circuit breakers use the principle of electromagnetic tripping to protect against damage to electrical equipment during short circuits. However, the biggest drawback of this method is its slow response speed and insensitive reaction. At the same time, due to the hysteresis effect of the electromagnetic tripping device, coupled with the reaction of mechanical components, the action time can reach 30ms (milliseconds) or even longer. Since the energy of the short-circuit spark is proportional to the current multiplied by the time, a very large spark will be generated when a short circuit occurs in the output line of the mechanical circuit breaker, which can easily ignite combustible materials and combustible gases. Furthermore, mechanical circuit breakers use bimetallic reeds for overcurrent and overload. The speed and duration of the response of these reeds are uncertain under different ambient temperatures. They operate much slower at low ambient temperatures than at high ambient temperatures. Therefore, in some cases, the bimetallic reeds may not operate even when the equipment and lines downstream of the circuit breaker are severely overheated. In addition, bimetallic reeds also carry the risk of metal fatigue.

[0076] The L-type high-speed electronic current-breaking intelligent protector uses silicon carbide MOSFETs with a common drain to form a bidirectional electronic switch, replacing traditional mechanical contacts. This fundamentally solves the wear and lifespan problems caused by mechanical contacts. Furthermore, because the MOSFET is a high-speed switch, its speed can reach MHz, making its current-breaking performance unmatched by any mechanical switch. Three sets of bidirectional silicon carbide switches and an inductor form a BUCK-BOOST voltage regulating chamber. This simplifies the previously required transformer or electronic power supply for achieving variable voltage, and its bidirectional structure allows it to operate in both DC and AC modes. In a 1:1 voltage output condition, switch group K2 of the BUCK-BOOST voltage regulating chamber is off, and switches K1 / K3 are on. During short-circuit arc extinguishing, switch group K1 is off, and switches K2 / K3 are on. In buck-boost voltage regulation mode, switch group K2 is off, and switches K1 / K3 operate with PWM dual-channel complementary pulse width modulation. During short-circuit arc extinguishing, the K1 switch group of the BUCK-BOOST voltage regulating chamber interrupts the current, while the K2 / K3 switch group consumes the residual current. This method is faster and has a more ideal short-circuit arc extinguishing effect than traditional type I or single type L electronic circuit breakers.

[0077] The L-type high-speed electronic current-breaking intelligent protector can perform stepless voltage regulation without a transformer, thus greatly saving costs. It has wide applications in mining environments, such as coal mine tunnel lighting, which uses low voltages of 63V or 127V. Traditionally, this requires a large and bulky transformer for voltage reduction, resulting in high losses, low efficiency, and high cost. The L-type high-speed electronic current-breaking intelligent protector uses BUCK-BOOST-PWM dual-channel complementary pulse width modulation, utilizing an inductor and an LC low-pass filter to complete the AC / DC voltage boost / buck operation. This results in low cost, high efficiency, and a small size.

[0078] In summary, the L-type high-speed electronic current-breaking intelligent protector, as a downstream protector of circuit breakers or air switches, eliminates short-circuit sparks caused by short circuits in the circuit breaker output line, effectively preventing fires caused by short circuits in electrical circuits or loads. Its rail-to-rail leakage current following technology can rapidly dissipate residual current in the line, even when there is no leakage or leakage exists. When a person accidentally touches a live conductor, the three-pole bidirectional electronic switch discharges the current in the line at a speed of NS (nanoseconds), resulting in an extremely slight electric shock sensation, similar to the voltage released by a lighter, thus ensuring personal safety. Combined with power metering and information communication, it can transmit data from the line to the platform in real time. Fault arc detection and combustible gas smoke collection elevate the prevention of electrical fires from post-accident remediation to pre-accident prevention.

[0079] Please see Figure 4 The power supply is input through interface J4 / interface J10. MOSFETs U3, U5, U12, and U17 are four silicon carbide MOSFETs connected in parallel, and the other MOSFETs follow the same pattern. Capacitors C6 and C7 are gate capacitors to reduce drive oscillation. Resistors R8, R9, and R10, along with capacitor C1, form a resistor-capacitor absorption circuit, and other circuits follow the same pattern. After passing through relays J2 and J9, the power supply is input to an LC low-pass filter composed of inductor L2 and capacitors C4 and C5, and then outputs from the leakage current sensor CT1 and the main current sensor CT2. The main current sensor CT2 detects the main current and also detects fault arcs.

[0080] Please see Figure 5 When the L-type high-speed electronic current interruption intelligent protector only needs short-circuit arc extinguishing, fault arc and no voltage regulation function, the 3-bridge GATE2 is at a low potential, the 1-bridge GATE1 and the 2-bridge GATE3 are at a high potential, the relay is energized, and the current flow direction is as follows.

[0081] Please see Figure 6 When the L-type high-speed electronic current interruption intelligent protector is in short-circuit arc extinguishing and fault arc detection operation, GATE1 of bridge 1 is at a low potential, while GATE2 / GATE3 of bridges 2 and 3 are at a high potential. Bridge 1 shuts off the main current output, and bridges 2 and 3 eliminate the residual current in the line through LC low-pass filters.

[0082] Please see Figure 7 and Figure 8 When the L-type high-speed electronic current interruption intelligent protector is in BUCK-BOOST boost / buck voltage regulation mode, the 3-bridge GATE2 is always in a high-level open state, and the 1st and 2nd bridges are in PWM interleaved complementary modulation mode. At this time, the output voltage waveform is inversely related to the input voltage waveform. In BUCK mode, the duty cycle of the 1st bridge is less than that of the 2nd bridge; in BOOST boost mode, the duty cycle of the 2nd bridge is greater than that of the 1st bridge. The voltage waveform across inductor L2 is shown in the mechanical diagram, and the output voltage waveform of capacitor C1 is shown in the diagram. Figure 8 As shown.

[0083] Please see Figure 9 and Figure 10 When the L-type high-speed electronic current interruption intelligent protector is in waveform correction mode, bridge 1 / bridge 2 enters PWM interleaved complementary modulation mode, which eliminates the voltage at the peak position and fills the voltage gap.

[0084] Please see Figure 11When the L-type high-speed electronic current interruption intelligent protector is in the short circuit current and fault arc detection, it adopts the current following comparison method and uses precision operational amplifier rectification and amplification to effectively avoid the distinction between starting current and short circuit current. At the same time, the fault arc detection adopts LC resonance detection. When the periodic current is greater than the resonant cavity current, it is regarded as a fault arc.

[0085] Please see Figure 12 When the L-type high-speed electronic current interruption intelligent protector enters the BUCK-BOOST step-up and step-down voltage regulation mode, the drive waveform diagram of bridge 1 and bridge 2 is shown. When the L-type high-speed electronic current interruption intelligent protector is in step-down mode, the duty cycle of bridge 1 is less than that of bridge 2. When it is in step-up mode, the duty cycle of bridge 1 is greater than that of bridge 2.

[0086] Please see Figure 13 The AC / DC power supply is fed to power module U2 to generate a 15V_POWER DC power supply. This power is then output through diodes D1 and D4 to filter capacitors C2 and C3, resulting in another 15V power supply. The 15V_POWER output is fed to the bridge driver transformer to obtain six sets of driver power supplies T1_1-T1_12. Each set passes through four rectifier bridge diodes to obtain a fully isolated voltage VCC1-VCC6. This voltage is then regulated by chips U1-U12 to provide the bridge driver, CPU power, ±12V power, and smoke sensor power. The 15V power supply is input to pins 13 and 15 of chip U3 to power the chip. Pins 12 and 14 are the output pins of the driver chip, which, through resistors R10 and R11, power chips U6 and U7.

[0087] Please see Figure 14 The 15V_POWER circuit charges capacitors C1-C5 via diode D1. When the power is off, the magnetic latching relay can still trip. Power is supplied to the magnetic latching control section via resistors R1 and R4. OA / OB sends the drive signal to the H-bridge via resistors R2 and R3. JDQK and SJ_OUT are connected to the fault lock. The 15V_POWER circuit charges capacitors C6-C9 via diode D6 and resistor R7. When the power is off, capacitors C6-C9 can maintain power supply to the motherboard.

[0088] Please see Figures 15-27 Chip U17 and chip U21 are high-speed isolated driver optocouplers. They send the high-speed drive signal from high-speed operational amplifier chip U15 to push-pull output transistors Q8 / Q13 / Q20 / Q30 for amplification and output to the gate of the bridge driver. START is the power-on drive signal, which controls whether the modulation pulse drive chip U16 sends modulation pulses.

[0089] Please see Figure 16The SS pin of the modulation pulse generator is connected to the enable terminal, which sends a power-on command to the MCU. When the power-on command arrives, the output is generated by voltage division between resistors R92 and R103.

[0090] Please see Figure 17 The relay closing and opening sections are composed of comparator U20. Comparators U20A and U20B form a window comparator and a dual-limit comparator. Comparator U20C generates the opening pulse, which is output by resistors R123 and R122.

[0091] Please see Figure 18 and Figure 19 The current control lock section uses I2_OUT as the main current input, which is amplified by resistor R187 and fed to pin 3 of amplifier U22A. After being output from pin 1, it is divided by resistors R184 and R194 and fed to the current acquisition chip. Simultaneously, it is fed to a precision rectifier amplifier via resistor R173 and then fed to the main current control lock composed of comparator U25. The leakage current is fed through I1_OUT to resistor R229, then amplified 5 times by amplifier U22B. After being divided by resistors R231 and R236, it is fed to the current acquisition chip. Simultaneously, it is fed to a precision rectifier amplifier via resistor R218 and then fed to the leakage current control lock composed of comparator U25.

[0092] Please see Figure 20 The gate input control sends a short-circuit lockout signal to the magnetic latching relay and simultaneously sends a signal to the MCU.

[0093] Please see Figure 21 The analog outputs of main current and leakage current are composed of operational amplifier U26. DAC1_MCU / DAC2_MCU are the analog outputs of the MCU, which are amplified by amplifier U26A / Amplifier U26B and output from pins 1 and 7. The short-circuit lockout signal is divided by resistors R204 / R220 and R206 / R221 and then sent to the MCU.

[0094] Please see Figure 22 Input voltage acquisition and output voltage acquisition are accomplished by acquisition transformer T5 / T6. The voltage is sent to transformer T5 / T6 through resistor R58 / R60, and the 220mV voltage signal is sent to the voltage acquisition chip. The voltage acquisition chip sends the signal to the MCU through the SPI signal transmission line.

[0095] Please see Figure 23 The MCU processes the data collected from each component and sends the resulting data values ​​and instructions to each unit.

[0096] Please see Figure 24 , Figure 25 and Figure 26In the communication section, J1 connects to the display screen. It connects the MCU programming interface, RS232 communication interface, and 4G communication interface to the display screen. Internal jumpers separate the necessary interfaces, connecting the RS232, programming interface, 4G communication USB interface, and +3.3V-+5V power supply interface to external interfaces. The +5V power supply passes through C1 / C2 / C3 and enters the 3.6V voltage regulator chip U1 to power the 4G communication module. EC20_EN is the 4G communication module power enable switch; when it is high, the 4G communication module power is turned on. The +3.6V power supply powers the module through pins 2, 24, 39, 41, and 52 of U2. Pins 8, 10, 12, and 14 are the module's SIM card interface, VDD_EXT is the +1.8V power interface, PERST is the reset interface, and RXT_EC20 / TXD_EC20 are the module's communication interfaces. USIM_RST / USIM_CLK / USIM_DATA / USIM_VDD are the SIM card connection ports, and NET_MODE / PERST_MCU / RXD3 / TXD3 are the module's indicator lights, level conversion ports, and network registration ports.

[0097] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. An L-shaped high-speed electronic circuit breaker intelligent protector, characterized in that, include: The system includes a three-channel T-type bidirectional electronic switch, an LC low-pass filter, a relay output channel, a current detection channel, and a main control module. The input terminal of the three-channel T-type bidirectional electronic switch is electrically connected to the input power supply. The three-channel T-type bidirectional electronic switch is electrically connected to the main control module. The output terminal of the three-channel T-type bidirectional electronic switch is electrically connected to the relay output channel. The output terminal of the relay output channel outputs voltage through the LC low-pass filter and the current detection channel. The three-channel T-type bidirectional electronic switch includes a first silicon carbide switch group K1, a second silicon carbide switch group K2, and a third silicon carbide switch group K3. The input terminal of the first silicon carbide switch group K1 is electrically connected to the input power supply. The output terminal of the first silicon carbide switch group K1 is electrically connected to the input terminals of the second silicon carbide switch group K2 and the third silicon carbide switch group K3, respectively. The output terminals of the second silicon carbide switch group K2 and the third silicon carbide switch group K3 are electrically connected to the input terminal of the relay output channel, respectively. The three-channel T-type bidirectional electronic switch also includes a connecting inductor L, the first end of which is electrically connected to the output end of the first silicon carbide switch group K1, and the second end of which is electrically connected to the input end of the third silicon carbide switch group K3. It also includes three RC snubber channels, the input of each of the RC snubber channels being electrically connected to the first silicon carbide switch group K1, the second silicon carbide switch group K2, and the third silicon carbide switch group K3, respectively.

2. The L-type high-speed electronic circuit breaker intelligent protector according to claim 1, characterized in that, It also includes a fault arc detection unit, the input terminal of which is electrically connected to the output terminal of the current detection channel, the output terminal of which is electrically connected to the main control module, and the output terminal of which is used to output voltage.

3. The L-type high-speed electronic circuit breaker protector according to claim 1, wherein It also includes a PWM drive generator, which is electrically connected to the three-channel T-type bidirectional electronic switch and the main control module.

4. The L-type high-speed electronic circuit breaker intelligent protector according to claim 1, characterized in that, The main control module is an MCU processor or a DSP processor.

5. The L-type high-speed electronic circuit breaker protector according to claim 2, wherein, The current detection channel includes a main current detection unit and a leakage current detection unit. The input terminal of the main current detection unit is electrically connected to the output terminal of the LC low-pass filter, and the output terminal of the main current detection unit is electrically connected to the leakage current detection unit. The output terminal of the leakage current detection unit is used to output voltage.

6. The L-type high-speed electronic circuit breaker protector according to claim 5, wherein, The current detection channel further includes an output voltage detection unit, which is electrically connected to the output terminal of the leakage current detection unit, and the output terminal of the output voltage detection unit is electrically connected to the output terminal of the fault arc detection unit.

7. The L-type high-speed electronic circuit breaker protector according to claim 6, wherein, It also includes a waveform correction unit, whose two input terminals are electrically connected to the output terminals of the leakage current detection unit and the fault arc detection unit, respectively, and whose output terminal is electrically connected to the main control module.

8. The L-type high-speed electronic circuit protector of claim 1, wherein, It also includes a combustible gas detection unit, a temperature detection unit, a voltage and current detection unit, and a communication unit, which are electrically connected to the main control module.

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