Railway communication machine room lightning protection monitoring system

Abstract

The utility model relates to the technical field of railway communication machine room lightning protection monitoring, in particular to a railway communication machine room lightning protection monitoring system, which comprises a lightning protection monitoring unit, a grounding resistance monitoring unit, an electrical integrity unit, a communication unit, a man-machine interaction unit and a power supply unit, wherein the lightning protection monitoring unit, the grounding resistance monitoring unit and the electrical integrity unit are respectively and electrically connected with the man-machine interaction unit, the communication unit is electrically connected with the man-machine interaction unit, and the power supply unit is used for supplying power to each unit. The utility model has the advantages that the lightning protection on-line detection is realized, the detection precision is improved, and the functions of remote monitoring, early warning and information management are realized; collected data are provided for the man-machine interaction unit, the operation condition is monitored in real time, the number of lightning strokes is recorded, when it is detected that the lightning protection unit is damaged and fails, an alarm is given rapidly, maintenance is conducted in time, signal lightning protection continuity is guaranteed, and therefore guarantee is provided for railway transportation safety.

Description

Technical Field

[0001] The utility model relates to the technical field of lightning protection monitoring for railway communication rooms, in particular to a lightning protection monitoring system for railway communication rooms. Background Art

[0002] With the rapid development of electrified railways in my country, railway communication rooms are becoming increasingly numerous and widely distributed. These rooms are crucial for organizing railway transportation, directing train operations, liaising between railway departments, and ensuring passenger service. Their operational reliability is crucial for ensuring the normal, safe, and stable operation of the entire railway line.

[0003] Railway communication rooms, core equipment for ensuring train safety, typically include power distribution equipment, high-frequency switching power supplies, UPS power supplies, dispatching system equipment, data network equipment, transmission equipment, video equipment, and air conditioning equipment. Railway communication rooms are located in buildings such as railway stations, signal towers, base stations, traction substations, and power distribution stations, and are distributed along railway lines, exposing them to the risk of lightning strikes.

[0004] However, the existing comprehensive lightning protection and grounding system cannot obtain sufficient grounding and lightning protection data and related information. The existing comprehensive lightning protection and grounding system generally has problems such as single monitoring object, low monitoring accuracy, and poor system stability, and cannot achieve accurate and reliable lightning protection monitoring. Summary of the Invention

[0005] The purpose of this utility model is to provide a railway communication room lightning protection monitoring system based on the above-mentioned deficiencies of the existing technology. By setting up various units for use in conjunction with each other, the utility model solves the technical problems that the existing comprehensive lightning protection and grounding systems in the railway power field generally have a single monitoring object, low monitoring accuracy, and poor system stability.

[0006] The purpose of this utility model is achieved by the following technical solutions:

[0007] A railway communication room lightning protection monitoring system, characterized by comprising a lightning protection monitoring unit, a ground resistance monitoring unit, an electrical integrity unit, a communication unit, a human-computer interaction unit, and a power supply unit;

[0008] The lightning protection monitoring unit, the ground resistance monitoring unit, and the electrical integrity unit are electrically connected to the human-computer interaction unit respectively, the communication unit is electrically connected to the human-computer interaction unit, and the power supply unit is used to supply power to each unit;

[0009] The lightning protection monitoring unit includes an MCU, a current signal sensor, a signal conditioning circuit, a clock circuit, a Flash storage circuit, a data transmission circuit and a power supply circuit. The current signal sensor, the signal conditioning circuit, the clock circuit, the Flash storage circuit and the data transmission circuit are all electrically connected to the MCU. The power supply circuit is used for power supply. The circuit is used to display and record events occurring in the lightning surge protector. The Flash storage circuit stores the collected current data.

[0010] The signal conditioning circuit comprises a resistance-capacitance voltage-dropping circuit, a voltage follower circuit, an absolute value amplifying circuit and a time-delay triggering circuit which are connected in sequence.

[0011] The RC step-down circuit includes a connected voltage-dividing attenuation resistor part, an isolation buffer part, and a rectification and filtering part.

[0012] The voltage divider attenuation part includes a resistor and capacitor group, the isolation buffer part includes a diode, the rectification and filtering part includes a voltage feedback amplifier, one end of the diode is connected to the same direction pin of the voltage feedback amplifier, and the other end of the diode is connected to +5V.

[0013] The power supply circuit converts the 220V AC power of the power line into +9V DC power. The +9V DC voltage is processed by the voltage stabilization module to obtain +5V. The +5V voltage output is filtered and stabilized to obtain a stable +3.3V.

[0014] The data transmission circuit adopts power carrier communication, that is, adopts a power carrier control chip.

[0015] The clock circuit is a real-time clock integrated circuit with an external crystal oscillator.

[0016] The advantages of the utility model are: realizing online detection of lightning protection, improving detection accuracy, realizing remote monitoring, early warning and information management functions; providing the collected data to the human-computer interaction unit, monitoring the operating status in real time, recording the number of lightning strikes, and quickly giving an alarm when damage and failure of the lightning protection unit is detected, timely maintenance, and ensuring the continuity of signal lightning protection, thereby providing protection for railway transportation safety and solving the technical problems of the existing comprehensive lightning protection and grounding systems in the railway power field, such as single monitoring object, low monitoring accuracy and poor system stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural block diagram of the utility model;

[0018] Figure 2 This is a structural block diagram of the lightning protection monitoring unit in the utility model;

[0019] Figure 3This is a circuit diagram of the MCU in the present utility model;

[0020] Figure 4 This is a circuit diagram of the power supply circuit in the present utility model;

[0021] Figure 5 This is a circuit diagram of the RC step-down circuit of the signal conditioning circuit in the present utility model;

[0022] Figure 6 This is a circuit diagram of a voltage follower circuit of a signal conditioning circuit in the present utility model;

[0023] Figure 7 This is a circuit diagram of the absolute value amplifier circuit of the signal conditioning circuit in the present utility model;

[0024] Figure 8 This is a circuit diagram of a time-delay trigger circuit of a signal conditioning circuit in the present utility model;

[0025] Figure 9 A circuit diagram of a clock circuit in the present utility model;

[0026] Figure 10 This is a circuit diagram of the Flash storage circuit in the present utility model;

[0027] Figure 11 This is a circuit diagram of the auxiliary power supply circuit in the utility model. DETAILED DESCRIPTION

[0028] The following is a further detailed description of the features of the present invention and other related features through embodiments in conjunction with the accompanying drawings to facilitate understanding by those skilled in the art:

[0029] Example: Figures 1 to 11 As shown, the railway communication room lightning protection monitoring system in this embodiment includes a lightning protection monitoring unit, a ground resistance monitoring unit, an electrical integrity unit, a communication unit, a human-computer interaction unit, and a power supply unit.

[0030] Among them, the lightning protection unit, the lightning protection monitoring unit, the ground resistance monitoring unit, and the electrical integrity unit are electrically connected to the human-computer interaction unit respectively, and the communication unit is electrically connected to the human-computer interaction unit;

[0031] The power supply unit is respectively connected to the lightning protection unit, the lightning protection monitoring unit, the ground resistance monitoring unit, the electrical integrity unit, the communication unit, the human-computer interaction unit, and the power supply unit to supply power;

[0032] The human-computer interaction unit includes an industrial computer and a display screen to realize local human-computer interaction functions. The core processing unit of the industrial computer can adopt GD32F303RFT6.

[0033] The lightning protection monitoring unit includes an MCU, a current signal sensor, a signal conditioning circuit, a clock circuit, a Flash storage circuit, a data transmission circuit and a power supply circuit. The current signal sensor, signal conditioning circuit, clock circuit, Flash storage circuit and data transmission are all electrically connected to the MCU. The power supply circuit is respectively connected to the current signal sensor, signal conditioning circuit, clock circuit, Flash storage circuit and data transmission and supplies power to the MCU.

[0034] In this embodiment, the current signal sensor is a Rogowski coil. Because it lacks an iron core, it avoids the hysteresis and magnetic saturation that occur with iron-core current transformers when measuring large short-circuit currents, thus preventing output waveform distortion. When measuring transient currents, the coil does not consume energy from the measured circuit, minimizing its impact. Furthermore, the Rogowski coil offers excellent electromagnetic shielding and high-voltage circuit insulation properties, along with a simple structure, a wide measurement range, a wide frequency bandwidth, and ease of fabrication.

[0035] In this embodiment, the MCU uses the STM32F103ZET6 chip. The STM32F103ZET6's ADC has a maximum sampling time of less than 1μs during operation, while the lightning surge protector signal simulated using inrush current is typically 1-4μs, meeting the system requirements. The STM32F103ZET6, a chip in the STM32F103xE series, has 144 pins, a rich analog peripheral set, and low- to medium-capacity on-chip memory. It operates at 72MHz and includes built-in high-speed memory, including up to 512KB of flash program memory and 64KB of SRAM, along with a static memory controller with four chip selects. It also includes four general-purpose 16-bit timers, three 12-bit ADCs, and two PWM timers, along with standard and advanced communication interfaces. Its operating voltage range is 2.0-3.6V, ensuring low-power applications. It includes three 12-bit analog-to-digital converters with 1μs conversion time, triple sample and hold function, 112 bidirectional I / O ports, all of which can be mapped to 16 external interrupts.

[0036] like Figure 3 The figure shows a minimum system for the STM32F103ZET6 MCU, including an STM32 microprocessor, a crystal oscillator circuit, a push-button reset circuit, an indicator light circuit, and a boost circuit. The STM32F103ZET6 has an internal RC oscillator that provides a clock for the internal phase-locked loop (PLL), but this is less accurate than an external crystal oscillator. The external clock circuit consists of a high-speed oscillator and a low-speed oscillator. The high-speed oscillator serves as the clock driver for the chip processor and STM32 peripherals, while the low-speed external oscillator drives the window watchdog timer and real-time clock.

[0037] The system uses an 8M external crystal in parallel with two 20pF chip capacitors as the clock source for the high-speed external clock signal, and a 32.768kHz external crystal in parallel with two 10pF chip capacitors as the clock source for the low-speed oscillator.

[0038] The power supply circuit converts the 220V AC power of the power line into +9V DC power. The +9V DC voltage is processed by the voltage regulator module to obtain +5V. The +5V voltage output is filtered and stabilized to obtain a stable +3.3V.

[0039] The monitoring system uses a Rogowski coil as a current signal sensor to monitor the current of the lightning surge protector. The sensor generates analog signals, which the system must convert to digital for data processing. The STM32F103ZET6 has three built-in 12-bit A / D converters, capable of converting voltages from 0 to 3.6V.

[0040] The data acquisition module of the system adopts +5V power supply, and the power supply circuit is as follows: Figure 4 As shown in the figure, P1 represents the switching power supply interface, which converts the 220V AC power line into +9V DC. The circuit uses capacitors to filter out the AC component. The +9V DC voltage is processed by an 8705 voltage regulator module to obtain a +5V voltage, which is then connected to the AMS1117. The AMS1117 is a positive low-dropout linear voltage regulator with a maximum voltage drop across it of no more than 1.3V. It can provide an 800mA output current and features built-in compensation capacitors for frequency compensation, thereby increasing reactive power and preventing voltage fluctuations while ensuring the AC component and system stability. The AMS1117 used in this circuit provides a +3.3V output voltage. The +5V output voltage is filtered and regulated to a stable +3.3V.

[0041] The low voltage signal obtained after the current signal passes through the current signal sensor (Rogowski coil) is -10V to +10V. Since the input voltage of the STM32F103ZET6 ADC module is less than 3.3V, the STM32 cannot directly collect this voltage signal and needs to further process the obtained voltage.

[0042] like Figure 8 As shown, the signal conditioning circuit includes a resistor-capacitor voltage-drop circuit, a voltage follower circuit, an absolute value amplifier circuit and a delay trigger circuit which are connected in sequence.

[0043] Among them, Figure 5As shown, the RC step-down circuit includes a connected voltage division and attenuation part, an isolation and buffering part, and a rectification and filtering part.

[0044] The voltage divider attenuation resistance part includes a resistor and capacitor group, the isolation buffer part includes a diode, and the rectification and filtering part includes a voltage feedback amplifier. One end of the diode is connected to the same direction pin of the voltage feedback amplifier, and the other end of the diode is connected to +5V.

[0045] The voltage-dividing and attenuating resistor section connects multiple resistors and capacitors of varying sizes in series and parallel, distributing most of the voltage drop across these resistors and capacitors to achieve voltage-dividing and attenuating effects. The isolation and buffering section includes the IN4149 diode, which prevents reverse current flow and provides unidirectional conduction, buffering, isolation, and rectification. The rectifier and filter section includes the OPA2889 voltage-feedback amplifier, which performs rectification and filtering functions. Since current has both positive and negative polarity, it also prevents excessive current from damaging the chip.

[0046] like Figure 6 As shown in the figure, the voltage follower circuit is used to increase the voltage from -1V to +1V to 0 to +1V, which serves as the ADC input of MCUSTM32F103ZET6.

[0047] like Figure 7 As shown, the input terminal TRIG of the absolute value amplifier circuit is connected to the output terminal of the voltage divider attenuation circuit, and the OPA2889 amplifier outputs a voltage of about 4V as the input of the delay trigger circuit.

[0048] like Figure 8 As shown in the figure, the function of the delay trigger circuit is that when a surge arrives, the absolute value amplifier circuit outputs a jump signal, and the TLC555 delay circuit outputs a low-level delay of about 100μs, which triggers the STM32F103ZET6 to generate an interrupt on the rising edge. To change the delay time, just change the product of the values of R52 and C49.

[0049] like Figure 9 As shown, the clock circuit is used to display and record the time when the lightning surge protector occurs. The clock circuit is a real-time clock integrated circuit with an external crystal oscillator, using DS1302.

[0050] The DS1302 chip operates at a voltage of 2.5V to 5.5V, draws 0.2μA of current, and is connected to a 32.768kHz crystal oscillator. The DS1302 writes and reads data very quickly, drawing 1.2mA of current.

[0051] The Flash storage circuit stores the collected current data and uses an external storage chip AT45DB161D.

[0052] The STM32F103ZET6 chip integrates 512KB of Flash. To ensure the accuracy of stored data and not affect the stability of the entire system during operation, an external Flash chip is used to store the collected current data. As shown in Figure 10, the external storage chip used is the AT45DB161D, a flash memory chip with a serial interface suitable for high-speed applications. It has a power-off power consumption of only a few microamperes, which helps reduce overall power consumption while improving system reliability.

[0053] The system is powered by a switching power supply and also requires an auxiliary power supply such as Figure 11 The figure shows the power supply for the STM32 minimum system, signal conditioning circuit, and Flash storage circuit. The ICL7660 is a low-power polarity reversal power converter with an input voltage range of 1.5V-10V and an operating frequency of 10kHz. Its function is to convert the 3.3V voltage to -3.3V and provide it to the STM32 minimum system and signal conditioning circuit.

[0054] The data transmission circuit adopts power line carrier communication and adopts power line carrier control chip.

[0055] The current signal sensor sends collected data to the data transmission module via the serial port. The power carrier module performs data modulation and demodulation on the power line. The current signal sensor collects and sends a signal to the power carrier control chip. The signal is amplified by the carrier processor, filtered by the transmission circuit, and then coupled to the 220V power line through the coupling circuit for transmission. During reception, the coupling capacitor isolates the power frequency signal and transmits the carrier signal. The carrier signal is then coupled to the chip's receiving circuit through the coupling circuit, filtered, and then sent to the chip for demodulation, completing the entire communication process.

[0056] Although the above embodiments have described the concepts and embodiments of the present invention in detail with reference to the accompanying drawings, ordinary technicians in this field can recognize that various improvements and modifications can still be made to the present invention without departing from the scope of the claims, so they are not described here one by one.

Claims

1. A railway communication room lightning protection monitoring system, characterized by: Including lightning protection monitoring unit, ground resistance monitoring unit, electrical integrity unit, communication unit, human-computer interaction unit, power supply unit; The lightning protection monitoring unit, the ground resistance monitoring unit, and the electrical integrity unit are electrically connected to the human-computer interaction unit respectively, the communication unit is electrically connected to the human-computer interaction unit, and the power supply unit is used to supply power to each unit; The lightning protection monitoring unit includes an MCU, a current signal sensor, a signal conditioning circuit, a clock circuit, a Flash storage circuit, a data transmission circuit and a power supply circuit. The current signal sensor, the signal conditioning circuit, the clock circuit, the Flash storage circuit and the data transmission circuit are all electrically connected to the MCU. The power supply circuit is used for power supply. The clock circuit is used to display and record events occurring in the lightning surge protector. The Flash storage circuit stores the collected current data.

2. A railway communication room lightning protection monitoring system according to claim 1, characterized in that: The signal conditioning circuit comprises a resistance-capacitance voltage-dropping circuit, a voltage follower circuit, an absolute value amplifying circuit and a time-delay triggering circuit which are connected in sequence.

3. A railway communication room lightning protection monitoring system according to claim 2, characterized in that: The RC step-down circuit includes a connected voltage-dividing attenuation resistor part, an isolation buffer part, and a rectification and filtering part.

4. A railway communication room lightning protection monitoring system according to claim 3, characterized in that: The voltage divider attenuation part includes a resistor and capacitor group, the isolation buffer part includes a diode, the rectification and filtering part includes a voltage feedback amplifier, one end of the diode is connected to the same direction pin of the voltage feedback amplifier, and the other end of the diode is connected to +5V.

5. The railway communication room lightning protection monitoring system according to claim 1, characterized in that: The power supply circuit converts the 220V AC power of the power line into +9V DC power. The +9V DC voltage is processed by the voltage stabilization module to obtain +5V. The +5V voltage output is filtered and stabilized to obtain a stable +3.3V.

6. The railway communication room lightning protection monitoring system according to claim 1, characterized in that: The data transmission circuit adopts power carrier communication, that is, adopts a power carrier control chip.

7. The railway communication room lightning protection monitoring system according to claim 1, characterized in that: The clock circuit is a real-time clock integrated circuit with an external crystal oscillator.

8. The railway communication room lightning protection monitoring system according to claim 1, characterized in that: The current signal sensor adopts a Rogowski coil.

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