Railway power supply screen insulation detection device based on resistance voltage division

Abstract

The utility model belongs to railway signal power supply screen's insulation detection technical field relates to a railway power supply screen insulation detection device based on resistance voltage division. Including: programmable power supply module, its output end is connected to power supply screen power supply bus, power supply bus and each power module electricity is connected, multichannel switch matrix module, including K0~K2n 2n+1 programmable switch, resistance module, including a plurality of resistance in series in each power supply loop, is used for converting leakage current into voltage division signal, signal acquisition module, with detection resistance module is in parallel, obtains voltage division signal, logic control and detection module are used for setting programmable power supply module output voltage, control programmable switch on -off, based on voltage division signal obtains voltage division voltage value and exports detection result. The utility model can real -time detection power supply screen equipment or power supply loop's insulation state, ensures the safety and reliability of railway power supply system.

Description

Technical Field

[0001] This utility model belongs to the field of insulation detection technology for railway signal power supply panels, and relates to an insulation detection device for railway power supply panels based on resistive voltage division. Background Technology

[0002] As the core power supply equipment of the railway signaling system, the railway signal power supply panel bears the important responsibility of providing stable and reliable power to key equipment such as track circuits, signals, and interlocking systems. The power supply panel system contains various power modules to meet the power supply needs of different equipment. These modules obtain electrical energy through the power supply bus and output power supply circuits with different voltage levels and forms of electrical energy.

[0003] However, current insulation testing of power supply panels mainly relies on manual, periodic testing using megohmmeters. This method is not only complex and inefficient, but also requires power-off operation, making real-time monitoring impossible and severely impacting the reliable operation of railway signaling systems. In practical applications, traditional testing methods have significant technical drawbacks: testing accuracy is greatly affected by human factors, making it difficult to detect early insulation degradation; they lack intelligent testing methods, making historical data comparison and trend analysis impossible; there are safety hazards during the testing process, and testing cannot be performed while the equipment is running; and maintenance costs are high, requiring specialized personnel and equipment.

[0004] More importantly, existing online insulation monitoring devices generally suffer from technical bottlenecks such as complex circuitry, high cost, poor anti-interference capabilities, and insufficient adaptability, making it difficult to meet the stringent requirements of railway signal power supply panels for real-time, accuracy, and reliability in insulation testing. Especially in harsh environments such as humidity and dust, the errors of traditional testing methods further increase, severely restricting the safe operation of railway power supply systems. Therefore, there is an urgent need to develop a new insulation testing technology to address the problems of real-time performance, accuracy, and safety in existing testing methods, ensuring the stable and reliable operation of railway signal power supply panels. Utility Model Content

[0005] The purpose of this invention is to solve the problems in the prior art and provide a railway power supply panel insulation detection device based on resistive voltage division, which can detect the insulation status of power supply panel equipment or power supply circuit in real time, and ensure the safety and reliability of railway power supply system.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This utility model provides an insulation detection device for railway power supply panels based on resistive voltage division, comprising:

[0008] A programmable adjustable power supply module, the output of which is connected to the power supply bus of the power supply panel; the power supply bus is electrically connected to each power supply module.

[0009] The multi-channel switch matrix module includes 2n+1 programmable switches from K0 to K2n; among them, K0 is a grounding switch connected to the ground wire; K1 to Kn are electrically connected to the positive wires of the power supply circuit of each power module; Kn+1 to K2n are connected to the negative wires of the power supply circuit of each power module.

[0010] The resistor module includes a ground detection branch resistor and multiple inter-loop detection branch resistors; the ground detection branch resistor is connected in series in the K0 grounding loop; the multiple inter-loop detection branch resistors are connected in series in each power supply loop; the resistor module is used to convert leakage current into a voltage divider signal.

[0011] The signal acquisition module is connected in parallel with the detection resistor module to acquire the voltage divider signal;

[0012] The logic control and detection module is electrically connected to the programmable power supply module, the multi-channel switch matrix module, and the signal acquisition module, respectively. It is used to set the output voltage of the programmable power supply module, control the on / off state of the programmable switch, obtain the voltage divider value based on the voltage divider signal, and output the detection result.

[0013] Preferably, the programmable adjustable power supply module has an output voltage range of DC200V-600V.

[0014] Preferably, each power supply module includes a 24V DC power supply, a 48V DC power supply, a 220V DC power supply, and a 25V AC power supply.

[0015] Preferably, it also includes an ambient temperature and humidity sensor, which is connected to the logic control and detection module.

[0016] Preferably, the ambient temperature and humidity sensor is an SHT20 or SHT45 digital sensor.

[0017] Preferably, it also includes an alarm module connected to the logic control and detection module.

[0018] Preferably, both the ground detection branch resistance and the inter-loop detection branch resistance are metal film resistors.

[0019] Preferably, the temperature coefficient of the metal film resistor is ≤50ppm / ℃.

[0020] Preferably, the programmable switch is an optocoupler-isolated relay.

[0021] Preferably, the signal acquisition module includes a 16-bit analog-to-digital converter with a sampling rate of not less than 1 kHz.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] This invention achieves fully automatic insulation testing of multiple power supply circuits in a power supply panel through the coordinated control of a programmable adjustable power supply module and a multi-channel switch matrix, solving the technical problems of low efficiency and poor real-time performance in traditional manual testing. By adopting the principle of resistance voltage division combined with a signal acquisition module, accurate measurement of insulation resistance can be achieved, significantly improving the reliability of testing. The multi-channel switch matrix module can perform both ground insulation testing and insulation testing between complex circuits. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a circuit diagram of an insulation detection device for a railway power supply panel based on resistive voltage division according to the present invention.

[0026] Figure 2 This is a circuit diagram of the logic control and detection module of this utility model.

[0027] Among them, K0~K16: programmable switches; Z1~Z4: inter-circuit detection branch resistance. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0031] In the description of the embodiments of this utility model, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, they are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the utility model. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0033] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0034] The present invention will now be described in further detail with reference to the accompanying drawings:

[0035] This utility model provides an insulation detection device for railway power supply panels based on resistive voltage division, such as... Figure 1 As shown, it includes:

[0036] A programmable adjustable power supply module (output voltage range DC200V-600V) has its output terminal connected to the power supply bus of the power panel; the power supply bus is electrically connected to each power supply module.

[0037] The multi-channel switch matrix module includes 2n+1 programmable switches (preferably optocoupler isolation relays) from K0 to K2n; wherein, K0 is a grounding switch connected to the ground wire; K1 to Kn are electrically connected to the positive wires of the power supply circuit of each power module; Kn+1 to K2n are connected to the negative wires of the power supply circuit of each power module.

[0038] The resistor module includes a ground detection branch resistor and multiple inter-loop detection branch resistors; the ground detection branch resistor is connected in series in the K0 grounding loop; the multiple inter-loop detection branch resistors are connected in series in each power supply loop; the resistor module is used to convert leakage current into a voltage divider signal.

[0039] The signal acquisition module is connected in parallel with the detection resistor module to acquire the voltage divider signal;

[0040] The logic control and detection module is electrically connected to the programmable power supply module, the multi-channel switch matrix module, and the signal acquisition module, respectively. It is used to set the output voltage of the programmable power supply module, control the on / off state of the programmable switch, obtain the voltage divider value based on the voltage divider signal, and output the detection result.

[0041] This invention achieves fully automatic insulation testing of multiple power supply circuits in a power supply panel through the coordinated control of a programmable adjustable power supply module and a multi-channel switch matrix, solving the technical problems of low efficiency and poor real-time performance in traditional manual testing. By adopting the principle of resistance voltage division combined with a signal acquisition module, it can achieve an insulation resistance measurement accuracy of ±1% within a wide voltage range of DC200V-600V, significantly improving the reliability of testing. The multi-channel switch matrix module can perform both ground insulation testing and insulation testing between complex circuits.

[0042] This utility model adopts a modular design, which allows the device to be adapted to railway power supply panels of different specifications. Only the wiring method of the switch matrix needs to be adjusted to meet customized requirements, which greatly reduces the maintenance cost of railway systems. In addition, the logic control and detection module can not only output the insulation status in real time, but also predict the insulation aging trend through historical data analysis, providing data support for preventive maintenance and comprehensively improving the safety and intelligent operation and maintenance level of railway power supply systems.

[0043] The logic control and detection module implements two detection modes by controlling the timing of the switching on and off of each switch in the multiplexer matrix module:

[0044] Power supply circuit to ground insulation detection mode: Control K1~Kn to be connected to K0 in sequence to detect the insulation status of the positive terminal of each power module to ground; Control Kn+1~K2n to be connected to K0 in sequence to detect the insulation status of the negative terminal of each power module to ground;

[0045] Insulation detection mode between power supply circuits: control the pairwise combination of K1~K2n to detect the insulation status between different power modules.

[0046] This invention achieves comprehensive detection of the insulation status of railway power supply panels through a dual-mode detection mechanism: on the one hand, the time-division multiplexing ground detection mode can systematically evaluate the ground insulation performance of the positive and negative poles of each power module, effectively identifying single-point grounding faults; on the other hand, through intelligent combination of inter-loop detection modes, it can accurately detect the insulation status between different power modules and promptly detect potential short-circuit risks between lines. This dual-mode collaborative detection design ensures both the comprehensiveness and reliability of the detection, and avoids system conflicts that may be caused by traditional detection methods through optimized switching timing control, providing dual protection for the safe operation of railway power supply systems.

[0047] For example, the operation logic of the multiplexer matrix module includes:

[0048] Power supply circuit to ground insulation detection mode: Perform 2n-step sequential detection, triggering K1~K2n to conduct with K0 for 1 second and then turn off;

[0049] Insulation detection mode between power supply circuits: Execute 4n 2 Step combination detection triggers Ki and Kj to conduct for 1 second and then turn them off, i=1~2n, j=1~2n, and skips the preset invalid combinations.

[0050] This invention achieves comprehensive coverage and intelligent avoidance of insulation testing for railway power supply panels through switch matrix control logic. Specifically, the step-by-step grounding detection mode systematically evaluates the grounding insulation status of each circuit, ensuring no omissions in the testing; the intelligent combination of inter-circuit detection modes accurately identifies the insulation performance between different circuits, while the invalid combination avoidance mechanism effectively prevents system conflict risks during the testing process. This ensures both the completeness and accuracy of the testing, and avoids potential equipment damage due to misoperation through preset safety logic, providing dual protection for the safe operation and maintenance of railway power supply systems.

[0051] like Figure 2The diagram shows the circuit schematic of the logic control and detection module, which mainly consists of interfaces, diodes, resistors, operational amplifiers, and power conversion chips. The circuit board receives a 5V power input through the VCC interface. The input power is filtered by capacitor C14 to remove high-frequency noise and ensure a stable +5V power supply to the circuit. The signal is input to the circuit board through the Header 2H interface (J2). The input signal first passes through diode D37 and then through resistor R80 for voltage division or current limiting. The pre-processed signal enters integrated circuit U8, which isolates and amplifies the input signal to improve the circuit's anti-interference capability. The pins of U8 include VDD1, VDDI (power input), INP, INN (signal input), OUTP, OUTN (signal output), GNDI, and GND2 (ground). The signal is converted and transmitted internally by these pins. The output signals (OUTP, OUTN) of U8 are connected to the input of operational amplifier U10A through resistors R76 and R77. Operational amplifier U10A further amplifies or buffers the input signal to meet the input requirements of subsequent circuits or devices. The signal processed by operational amplifier U10A is output through the AMP SINGLE1 interface as the final signal output of the circuit board. Simultaneously, the circuit board has multiple ground pins (GND), connected to the ground plane of the circuit board, providing a stable reference potential and ensuring circuit stability and anti-interference capability. When a DC 500V voltage is applied to the detection circuit, the voltage across the precision voltage detection resistor is reduced to a range acceptable to the AMC1311 chip through voltage division using series resistors. An SM4CANB-02HTG TVS diode provides overvoltage protection for the input signal. After passing through a filter capacitor, the signal enters pins 2 (positive input) and 4 (input-side ground) of the operational amplifier chip. Subsequently, an LM358 chip forms a differential signal feedback circuit to remove noise from the signal, converting the sensor signal into a standard voltage output. This output then enters the microcontroller (STM32F103VCT6) for analog-to-digital conversion, and after calculation, outputs the insulation detection result and corresponding alarm information.

[0052] For example, this utility model can simultaneously perform insulation testing on power modules of different voltage levels and types in railway power supply panels, including various specifications such as 24V / 48V / 220V DC power and 25V AC power (each power supply is configured with corresponding power supply circuit resistors Z1~Z4). It effectively solves the technical problem that traditional testing equipment cannot adapt to the coexistence of multiple types of power supplies in railway power supply panels, realizes unified testing and centralized management of complex power supply systems, significantly improves testing efficiency and system applicability, and provides reliable technical support for the standardized maintenance of railway power supply panels.

[0053] The resistance values ​​of each resistor in the resistor module are dynamically adjusted according to the output voltage of the programmable adjustable power supply module and the expected leakage current threshold. This ensures measurement safety under high-voltage conditions while also taking into account measurement accuracy under low-voltage conditions. It effectively solves the problem of insufficient adaptability of traditional fixed resistance detection methods in wide voltage range applications, and provides flexible and accurate technical support for the insulation status monitoring of railway power supply systems under various operating conditions.

[0054] This utility model's insulation testing device also includes an environmental temperature and humidity sensor, model SHT20 or SHT45, connected to the logic control and detection module. The logic control and detection module dynamically corrects the resistance values ​​of each resistor based on the measurement parameters from the environmental temperature and humidity sensor. The introduction of the environmental temperature and humidity sensor enables the system to perceive changes in the detection environment in real time and dynamically correct the resistance parameters through intelligent algorithms, effectively eliminating the influence of temperature and humidity fluctuations on the detection results. This ensures the consistency and reliability of detection data under different climatic conditions, providing a more accurate safety guarantee for the stable operation of railway power systems in various complex environments.

[0055] Both the ground-to-ground detection branch resistance and the inter-loop detection branch resistance are metal film resistors with a temperature coefficient ≤50ppm / ℃. The independent setting of the ground-to-ground detection branch resistance and the inter-loop detection branch resistance enables accurate measurement in two detection modes. Furthermore, the low temperature coefficient (≤50ppm / ℃) of the metal film resistors effectively suppresses the influence of temperature changes on the measurement results, ensuring the stability and repeatability of the detection data under different environmental conditions. This guarantees both detection sensitivity and improves the long-term operational stability of the system, providing a more accurate and reliable technical guarantee for the insulation status monitoring of railway power supply panels.

[0056] This utility model insulation detection device also includes an alarm module connected to the logic control and detection module. When the acquired voltage divider value exceeds the preset insulation fault threshold, the logic control and detection module can quickly trigger the alarm module to issue an audible and visual alarm signal, promptly attracting the attention of relevant personnel and enabling them to be aware of the insulation fault at the first moment, thus preventing the fault from worsening. At the same time, the alarm module will also generate an alarm log containing fault location information, providing maintenance personnel with accurate information for quickly locating the fault point, greatly shortening the time for fault diagnosis and repair, effectively improving the reliability and safety of equipment operation, reducing the risk of equipment damage and production stoppage caused by insulation faults, and ensuring the stable operation of the entire system.

[0057] This utility model also provides a method for insulation testing of railway power supply panels based on resistive voltage division, including the following steps:

[0058] S1: Initialize the detection system and set the output voltage of the programmable adjustable power supply module;

[0059] S2: Sequentially turn on the switch combinations between each power supply circuit and the ground wire (K1-K2n are respectively combined with K0), collect the first voltage division signal of the resistor module and calculate the insulation resistance value to ground;

[0060] S3: Sequentially connect different power supply circuits (connect the switches between K1-K2n according to the preset combination), collect the second voltage divider signal of the resistor module and calculate the insulation resistance value between the circuits.

[0061] S4: Determine whether the insulation resistance to ground and the insulation resistance between circuits exceed the threshold, and generate an insulation status report.

[0062] Example

[0063] 1. The insulation detection device in this embodiment specifically includes:

[0064] Programmable adjustable power supply module: The output voltage range is DC200V-600V, and the voltage level can be adjusted according to the detection requirements.

[0065] The multi-channel switch matrix module consists of 17 high-reliability programmable switches K0 to K16, where: K0 is connected to the system ground wire; K1 to K8 are respectively connected to the positive wires of four power modules (24V DC, 48V DC, 220V DC, and 25V AC); and K9 to K16 are respectively connected to the negative wires of the above power modules.

[0066] Resistor module: detects the resistance of the branch to ground, connected in series in the K0 grounding loop; detects the resistance of the branch between loops (Z1~Z4), with different resistance values ​​configured according to the power supply type (e.g., 1kΩ for 24V loop, 10kΩ for 220V loop), all of which are metal film resistors with a temperature coefficient ≤50ppm / ℃.

[0067] Signal acquisition module: Includes a 16-bit analog-to-digital converter with a sampling rate of not less than 1kHz, connected in parallel with the resistor module, to acquire voltage divider signals in real time.

[0068] Logic control and detection module: Based on STM32 microcontroller, it sets the output voltage of the programmable adjustable power supply module, controls the switching sequence, calculates the insulation resistance, and outputs a detection report.

[0069] Ambient temperature and humidity sensor: Employs SHT45 digital sensor to monitor environmental parameters in real time for dynamic correction of resistance values.

[0070] 2. Detection Method

[0071] Power supply circuit ground insulation detection mode: As shown in Table 1, 16 sequential detection steps are performed, triggering Kn and K0 to conduct for 1 second and then turning off, n=1~16;

[0072] Table 1. Insulation Status and Operation Logic Relationships Between Different Core Wires and Ground

[0073]

[0074] Insulation detection mode between power supply circuits: Performs 256 steps of combined detection, triggering Ki and Kj to conduct for 1 second and then turning them off (i=1~16, j=1~16), and skipping preset invalid combinations. Invalid combinations include: switching combinations between the positive and negative circuits of the same power module and preset switching combinations between electrical isolation circuits.

[0075] This method enables a comprehensive assessment of the power supply panel's insulation to ground and the insulation status between circuits. The step-by-step detection strategy ensures independent measurement of the insulation performance of each power supply circuit while accurately identifying potential insulation faults between circuits. The intelligent threshold judgment mechanism provides maintenance personnel with an intuitive and reliable insulation status report. This method is simple to operate and provides comprehensive detection, effectively solving the technical problems of low efficiency and incomplete coverage in traditional insulation detection methods, and providing a scientific and effective detection means for the safe operation and maintenance of railway power supply systems.

[0076] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An insulation testing device for railway power supply panels based on resistive voltage division, characterized in that, include: The programmable adjustable power supply module has its output connected to the power supply bus of the power supply panel; The power supply bus is electrically connected to each power module; The multi-channel switch matrix module includes 2n+1 programmable switches from K0 to K2n; among them, K0 is a grounding switch connected to the ground wire; K1 to Kn are electrically connected to the positive wires of the power supply circuit of each power module; Kn+1 to K2n are connected to the negative wires of the power supply circuit of each power module. The resistor module includes a ground detection branch resistor and multiple inter-loop detection branch resistors; the ground detection branch resistor is connected in series in the K0 grounding loop; the multiple inter-loop detection branch resistors are connected in series in each power supply loop; the resistor module is used to convert leakage current into a voltage divider signal. The signal acquisition module is connected in parallel with the detection resistor module to acquire the voltage divider signal; The logic control and detection module is electrically connected to the programmable power supply module, the multi-channel switch matrix module, and the signal acquisition module, respectively. It is used to set the output voltage of the programmable power supply module, control the on / off state of the programmable switch, obtain the voltage divider value based on the voltage divider signal, and output the detection result.

2. The railway power supply panel insulation detection device based on resistive voltage division according to claim 1, characterized in that, The programmable adjustable power supply module has an output voltage range of DC200V-600V.

3. The railway power supply panel insulation detection device based on resistive voltage division according to claim 1, characterized in that, Each power supply module includes a 24V DC power supply, a 48V DC power supply, a 220V DC power supply, and a 25V AC power supply.

4. The railway power supply panel insulation detection device based on resistive voltage division according to claim 1, characterized in that, It also includes an ambient temperature and humidity sensor, which is connected to the logic control and detection module.

5. The railway power supply panel insulation detection device based on resistive voltage division according to claim 4, characterized in that, The ambient temperature and humidity sensor is an SHT20 or SHT45 digital sensor.

6. The railway power supply panel insulation detection device based on resistive voltage division according to claim 1, characterized in that, It also includes an alarm module, which is connected to the logic control and detection module.

7. The railway power supply panel insulation detection device based on resistive voltage division according to claim 1, characterized in that, Both the ground detection branch resistance and the inter-loop detection branch resistance are metal film resistors.

8. The railway power supply panel insulation detection device based on resistive voltage division according to claim 7, characterized in that, The temperature coefficient of the metal film resistor is ≤50ppm / ℃.

9. The railway power supply panel insulation detection device based on resistive voltage division according to claim 1, characterized in that, The programmable switch is an optocoupler-isolated relay.

10. The railway power supply panel insulation detection device based on resistive voltage division according to claim 1, characterized in that, The signal acquisition module includes a 16-bit analog-to-digital converter with a sampling rate of not less than 1 kHz.

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