Gas density state monitoring system for medium-voltage switch cabinet

Abstract

The utility model relates to the field of gas density state monitoring, and provides a gas density state monitoring system for a medium-voltage switch cabinet, which comprises a gas density transmitter, a display module, an RS485 concentrator, an intelligent I ED and a monitoring background, the number of the gas density transmitters is multiple, each gas density transmitter is arranged in a corresponding medium-voltage switch cabinet gas chamber, and each gas density transmitter is connected to a corresponding display module; the number of the display modules is multiple, and each display module is connected to the corresponding RS485 concentrator. All the RS485 concentrators communicate with the intelligent I ED, and data collected by the gas density transmitter is transmitted to a monitoring background through the intelligent I ED. According to the utility model, the display module is convenient for technicians to check monitoring data on site and intuitively master the real-time state in the gas chamber of the switch cabinet, thereby facilitating the timely formulation of a maintenance scheme, improving the maintenance efficiency and reducing the safety risk.

Description

Technical Field

[0001] This utility model relates to the field of gas density status monitoring, and in particular to a gas density status monitoring system for medium-voltage switchgear. Background Technology

[0002] The statements in this section are merely background information related to this utility model and do not necessarily constitute prior art.

[0003] Sulfur hexafluoride (SF6) gas is widely used in the electrical insulation monitoring industry of power systems. It is a colorless, odorless, non-toxic, and non-flammable gas. Under a uniform electric field, its insulating properties are three times that of air; at four atmospheres, its insulating properties are comparable to those of transformer oil. However, as a greenhouse gas, SF6 cannot be released indiscriminately. If SF6 electrical products leak during use, not only will their reliable and safe operation be compromised, but it will also damage the environment. Therefore, real-time online monitoring for SF6 gas leaks has become one of the important tasks for the power sector.

[0004] Currently, in the field of gas status monitoring for medium-voltage switchgear in power systems, gas density switches are commonly used to monitor gas density. Gas leaks are only detected when the gas density drops to an alarm or lockout value, triggering an alarm signal. This approach has significant drawbacks: firstly, it cannot monitor gas status changes in real time; secondly, the leakage volume is large, which is environmentally unfriendly. Therefore, based on application environment and market demand, there is an urgent need to develop an online gas density monitoring system for medium-voltage switchgear, requiring advantages such as accurate data acquisition, reliable data transmission, clear architecture, standardized communication, and simple construction. While patent CN218938052U can achieve the above functions, the monitoring data inside the switchgear gas chamber needs to be viewed through a monitoring backend. When a gas leak occurs, on-site personnel cannot intuitively grasp the real-time status inside the switchgear gas chamber, cannot promptly formulate appropriate maintenance plans, resulting in low maintenance efficiency and potential safety hazards. Utility Model Content

[0005] The purpose of this invention is to provide a gas density status monitoring system for medium-voltage switchgear, which solves the technical problem that the real-time status of the switchgear gas chamber cannot be displayed locally. This system facilitates intuitive understanding of the real-time status of the switchgear gas chamber when gas leakage occurs, and is conducive to the timely formulation of maintenance plans.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: including a gas density transmitter, a display module, an RS485 hub, an intelligent LED, and a monitoring backend;

[0007] There are multiple gas density transmitters, each of which is installed in the gas chamber of the corresponding medium-voltage switchgear, and each of which is connected to the corresponding display module.

[0008] There are multiple display modules, and each display module is connected to a corresponding RS485 hub;

[0009] All of the RS485 hubs communicate with the smart IED, transmitting the data collected by the gas density transmitter to the monitoring backend via the smart IED.

[0010] Furthermore, the gas density transmitter includes: a temperature acquisition sensor, a pressure acquisition sensor, a signal isolation and processing unit, a processor, and an RS485 module;

[0011] The temperature and pressure data collected by the temperature and pressure sensors are isolated and processed by the signal isolation and processing unit before being transmitted to the processor. The processor then transmits the processed data to the corresponding display module via the RS485 module.

[0012] Furthermore, the gas density transmitter also includes a battery module, which is used to power the internal circuitry of the gas density transmitter.

[0013] Furthermore, the display module 2 includes a two-channel RS485 communication module, a signal isolation module, a processor, and an LED display module;

[0014] One RS485 module communicates with the gas density transmitter to receive temperature and pressure data output by the gas density transmitter.

[0015] The signal isolation module is used to isolate the data related to the RS485 module from the internal processing. The processor calculates the gas density based on the received temperature and pressure data, and drives another RS485 module to output digital signals of gas temperature, pressure and density information to the RS485 hub.

[0016] Furthermore, the RS485 hub includes a multi-channel RS485 input module, a single RS485 output module, two signal isolation modules, and a processor;

[0017] The multi-channel RS485 input module is connected to the RS485 output of the corresponding display module to receive digital signals of air pressure, temperature, pressure and density information;

[0018] Two signal isolation modules are connected to the two serial interfaces of the CPU respectively, and are used to isolate the relevant signals of the RS485 module from the processor;

[0019] The processor receives multiple RS485 signals, processes and aggregates them into a single RS485 signal, and then outputs it to the IED through the RS485 output module.

[0020] Furthermore, the intelligent IDE4 includes a multi-channel RS485 input module, a multi-channel network port module, a multi-channel optical port module, two signal isolation modules, and a CPU module;

[0021] The multi-channel RS485 input module is connected to the RS485 output of the hub to receive digital signals of gas temperature, pressure and density information;

[0022] The two signal isolation modules are configured as follows: one signal isolation module is used to isolate the RS485 module signal from the CPU module, and the other signal isolation module is used to isolate the network port module signal, the optical port module signal from the CPU module.

[0023] The processor converts the received multiple RS485 signals into a standard communication protocol and then outputs them to the monitoring backend through a network port module or an optical port module.

[0024] Furthermore, the monitoring backend enables the display of monitoring data and system control functions.

[0025] Furthermore, the display module is embedded in the switch cabinet panel.

[0026] Furthermore, the RS485 hub is mounted on a DIN rail and is centrally mounted on the standard DIN rail of the communication cabinet.

[0027] Furthermore, the intelligent IED4 is installed inside the communication cabinet using a rail-mounted or rack-mounted design.

[0028] The technical solution of this utility model has the following beneficial effects:

[0029] 1. This utility model involves installing gas density transmitters in the corresponding medium-voltage switchgear gas chambers to acquire monitoring data within the gas chambers. Each gas density transmitter is connected to its corresponding display module, which allows technicians to view the monitoring data locally and intuitively grasp the real-time status of the switchgear gas chambers. This facilitates the timely development of maintenance plans, improves maintenance efficiency, and reduces safety risks.

[0030] 2. The architecture of this utility model is divided into an equipment layer, an interval layer and a station control layer. The layers are clearly defined and the construction and maintenance are simple.

[0031] 3. This utility model is based on RS485 bus and Ethernet or fiber optic network networking, and adopts standardized communication protocols to ensure the reliability and scalability of system communication.

[0032] 4. The RS485 communication of this utility model preferably uses the Modbus / RTU protocol, and the Ethernet or fiber optic network preferably uses the IEC61850 standard protocol.

[0033] 5. This utility model adopts a redundant design, with standard interfaces reserved for both the RS485 hub and the smart ED, facilitating the connection of subsequent expansion devices.

[0034] 6. The internal data transmission of this utility model adopts a standardized protocol, thereby enabling compatibility and interchangeability of equipment from different manufacturers.

[0035] Advantages of the present invention in additional aspects will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0036] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.

[0037] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0038] Figure 2 This is a structural diagram of the gas density transmitter of this utility model.

[0039] Figure 3 This is a structural diagram of the display module of this utility model.

[0040] Figure 4 This is a structural diagram of the RS485 hub of this utility model.

[0041] Figure 5 This is a structural diagram of the intelligent LED of this utility model. Detailed Implementation

[0042] It should be noted that the following detailed description is exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0043] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this utility model.

[0044] Where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0045] like Figure 1-5As shown, this utility model discloses a gas density status monitoring system for medium-voltage switchgear, including a gas density transmitter, a display module, an RS485 hub, an intelligent IED, and a monitoring backend.

[0046] The gas density transmitter collects the gas temperature and pressure values ​​in the switch chamber in real time.

[0047] The gas density value is calculated using temperature and pressure values.

[0048] The gas temperature, pressure, and density values ​​are transmitted to the display module via a wired connection.

[0049] The display module is embedded in the switch cabinet panel and is used to display the real-time gas temperature, pressure and density values ​​inside the switch cabinet.

[0050] The display module uses the RS485 communication protocol to communicate with the monitoring backend via an RS485 hub and a smart IED.

[0051] Gas density transmitters and display modules can be set up one-to-one, or one display module can be connected to multiple gas density transmitters.

[0052] Gas density transmitters and display modules are installed in the equipment layer, RS485 hubs are installed in the bay layer, and smart LEDs and monitoring backends are installed in the station control layer.

[0053] It should be noted that intelligent substations are divided into three levels based on their structure and function: equipment level, bay level, and station control level.

[0054] The equipment layer includes intelligent devices, merging units, and intelligent terminals composed of primary equipment and intelligent components, which complete the substation's power distribution, transformation, transmission, and related functions such as measurement, control, protection, metering, and status monitoring.

[0055] Interval layer equipment generally refers to secondary equipment such as relay protection devices and measurement and control devices, which realize the function of using the data of an interval and acting on the primary equipment of that interval, that is, communicating with various remote inputs / outputs, intelligent sensors and controllers.

[0056] The station control layer includes subsystems such as automation system, station domain control, communication system, and time synchronization system. It realizes the measurement and control functions for the entire station or one or more primary equipment, and completes related functions such as data acquisition and monitoring and control (SCADA), operation interlocking, synchronization phasor acquisition, electrical energy acquisition, and protection information management.

[0057] In some embodiments, the gas density transmitter incorporates high-precision temperature and pressure sensors, enabling real-time acquisition of gas temperature and pressure within the switchgear chamber. The gas density value is then calculated by combining the temperature and pressure readings. It supports RS485 interface and MODBUS standard protocol transmission. The gas density transmitter and display module can be connected via digital interfaces such as RS485 and I2C; alternatively, analog interfaces such as 0-5V and 4-20mA can be used. It should be noted that the method of calculating gas density using temperature and pressure values ​​is existing technology, and this invention does not improve the algorithm.

[0058] Preferably, the gas density transmitter adopts a miniaturized design, using a sensor element that integrates temperature and pressure, TO-92 package, and is directly welded to a miniature glass-sealed terminal. While achieving gas path sealing and measurement accuracy, the transmitter as a whole achieves a high degree of integration, thus meeting the requirements of the limited installation space of the switch cabinet.

[0059] In some implementations, the display module can read density transmitter data in real time and display the temperature, pressure, and density values ​​of the gas in the switchgear chamber locally.

[0060] Preferably, the display modules are configured one-to-one with the number of air chambers in the switchgear. An 80mm*80mm square hole can be made in an easily observable position on the switchgear panel to embed and install the display module, which is convenient for on-site viewing during equipment maintenance. The installation method of the display module, i.e. the shape and size of the opening on the switchgear panel, can be set by those skilled in the art according to the actual needs on site, as long as the relevant parameters can be displayed and viewed easily. No further restrictions are imposed here.

[0061] In some implementations, the RS485 hub connects the display module to the southbound interface and the smart IED to the northbound interface for aggregation and reliable transmission of the 485 bus.

[0062] Preferably, the RS485 hub is installed on a DIN rail and is centrally mounted on the standard DIN rail of the communication cabinet.

[0063] In some implementations, the south-facing interface of the intelligent IED connects to an RS485 hub, while the north-facing interface connects to the monitoring backend. This allows for both communication protocol conversion and conversion from RS485 bus to Ethernet or fiber optic network. The intelligent IED can receive information from multiple RS485 hubs, convert it into a standard communication protocol, and then communicate with the monitoring backend. Common communication protocols are supported, including IEC61850, MODBUS, and IEC104.

[0064] In some implementations, the monitoring backend can realize the background display of monitoring data and system control functions.

[0065] In some implementations, the smart IED can be installed inside a communication cabinet using a rail or rack mounting method.

[0066] like Figure 2 As shown, the gas density transmitter includes a temperature acquisition sensor, a pressure acquisition sensor, a signal isolation and processing module, a CPU module, a power supply module, and an RS485 communication module. The power supply module converts the externally input DC24V into DC5V and DC3.3V to power the internal circuitry of the transmitter. The temperature and pressure acquisition sensors acquire the gas temperature and pressure values ​​in the switchgear chamber. The signal isolation and processing module uses an optocoupler TLP271 to isolate the relevant signals from the temperature and pressure acquisition sensors from the internal CPU module. After processing by an instrumentation amplifier AD8221, the signals are converted into signals that the CPU module can acquire. Based on the acquired temperature and pressure signals, the CPU module calculates the gas density using a built-in dedicated gas density algorithm, and then drives the RS485 module to output a digital signal carrying the gas temperature, pressure, and density information. It should be noted that this gas density algorithm is existing technology, and this invention does not improve the algorithm or program.

[0067] like Figure 3 As shown, the display module includes two RS485 communication modules, a signal isolation module, a CPU module, a power supply module, and an LED display module. The power supply module converts the externally input DC24V to DC3.3V to power the internal circuitry of the display module. One RS485 module communicates with the transmitter, receiving the gas temperature, pressure, and density signals output by the transmitter. The signal isolation model is ADuM1300, used to isolate the relevant signals from the RS485 module from the internal CPU module to ensure the safety and reliability of signals entering the CPU module. The CPU module drives the LED module to display the received temperature, pressure, and density signals. The other RS485 module is used to output digital signals carrying gas pressure, temperature, pressure, and density information.

[0068] like Figure 4As shown, the RS485 hub includes a multi-channel RS485 input module (commonly 4 / 8 / 16 channels), a single RS485 output module, two signal isolation modules, a CPU module, a power isolation module, and a power module. The power module converts the externally input DC24V to DC3.3V for powering the hub's internal circuitry. The power isolation module, model JW3510, isolates the converted DC3.3V from the external circuitry, ensuring the reliability of the 3.3V voltage. The multi-channel RS485 input module connects to the RS485 output of the display module, receiving digital signals carrying information on air pressure, temperature, pressure, and density. The two signal isolation modules, both model ADuM1300, connect to the CPU serial interface, isolating the RS485 module's signals from the CPU module to ensure the safe and reliable input / output of the CPU module's signals. The CPU module processes and aggregates the received multi-channel RS485 signals into a single RS485 signal, which is then output to the smart LED via the RS485 output module.

[0069] like Figure 5 As shown, the intelligent IED includes a multi-channel RS485 input module (commonly 4 / 8 / 16 channels), a multi-channel Ethernet port module (commonly 2 / 4 / 8 channels), a multi-channel optical port module (commonly 2 / 4 channels), two signal isolation modules, a CPU module, a power isolation module, and a power supply module. The power supply module converts the external AC220V input into DC5V and DC3.3V for use by the intelligent IED. The ED is powered by its internal circuitry. A JW3510 power isolation module isolates the converted DC5V and DC3.3V from external sources, ensuring the reliability of these voltages. A multi-channel RS485 input module connects to the hub's RS485 output, receiving digital signals carrying gas temperature, pressure, and density information. Two ADuM1300 signal isolation modules isolate the RS485 module signals from the CPU module, while the other isolates the network port and optical port signals from the CPU module, ensuring the safe and reliable input and output of the CPU module signals. The CPU module receives multiple RS485 signals and converts them into standard communication protocols such as Modbus and IEC61850, then outputs them to the monitoring backend via the network or optical port.

[0070] In operation, the temperature and pressure sensors in the gas density transmitter acquire the gas temperature and pressure signals from the gas chamber of the medium-voltage switchgear, respectively. The CPU module built into the gas density transmitter calculates the gas density using a dedicated gas density algorithm based on the acquired temperature and pressure signals, then drives the RS485 module to output digital signals of gas temperature, pressure, and density information to the display module. The CPU module in the display module drives the LED module to display the received temperature, pressure, and density signals, and outputs the equivalent digital signals of gas pressure, temperature, pressure, and density information to the RS485 hub via the RS485 module. The CPU module in the RS485 hub processes and aggregates the RS485 signals from multiple display modules into a single RS485 signal, which is then output to the smart LED via the RS485 output module. The CPU module in the smart LED converts the received RS485 signals from multiple RS485 hubs into a unified standard communication protocol, such as Modbus or IEC61850, and then outputs them to the monitoring backend via a network port or optical port. The monitoring backend enables the display of monitoring data within the medium-voltage switchgear and provides system control functions.

[0071] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solution of the present utility model are still within the scope of protection of the present utility model.

Claims

1. A gas density status monitoring system for medium-voltage switchgear, characterized in that, Includes a gas density transmitter, display module, RS485 hub, smart IED and monitoring backend; There are multiple gas density transmitters, each of which is installed in the gas chamber of the corresponding medium-voltage switchgear, and each of which is connected to the corresponding display module. There are multiple display modules, and each display module is connected to a corresponding RS485 hub; All of the RS485 hubs communicate with the intelligent IED, transmitting the data collected by the gas density transmitter to the monitoring backend via the intelligent IED.

2. The gas density status monitoring system for medium-voltage switchgear as described in claim 1, characterized in that, The gas density transmitter includes: a temperature acquisition sensor, a pressure acquisition sensor, a signal isolation and processing unit, a processor, and an RS485 module; The temperature and pressure data collected by the temperature and pressure sensors are isolated and processed by the signal isolation and processing unit before being transmitted to the processor. The processor then transmits the processed data to the corresponding display module via the RS485 module.

3. The gas density status monitoring system for medium-voltage switchgear as described in claim 2, characterized in that, The gas density transmitter also includes a battery module, which is used to power the internal circuitry of the gas density transmitter.

4. A gas density status monitoring system for medium-voltage switchgear as described in claim 2, characterized in that, The display module includes a two-channel RS485 communication module, a signal isolation module, a processor, and an LED display module; One RS485 module communicates with the gas density transmitter to receive temperature and pressure data output by the gas density transmitter. The signal isolation module is used to isolate the data related to the RS485 module from the internal processing. The processor calculates the gas density based on the received temperature and pressure data, and drives another RS485 module to output digital signals of gas temperature, pressure and density information to the RS485 hub.

5. A gas density status monitoring system for medium-voltage switchgear as described in claim 1, characterized in that, The RS485 hub includes a multi-channel RS485 input module, a single RS485 output module, two signal isolation modules, and a processor. The multi-channel RS485 input module is connected to the RS485 output of the corresponding display module to receive digital signals of air pressure, temperature, pressure and density information; Two signal isolation modules are connected to the two serial interfaces of the CPU respectively, and are used to isolate the relevant signals of the RS485 module from the processor; The processor receives multiple RS485 signals, processes and aggregates them into a single RS485 signal, and then outputs it to the IED through the RS485 output module.

6. A gas density status monitoring system for medium-voltage switchgear as described in claim 1, characterized in that, The intelligent IED4 includes a multi-channel RS485 input module, a multi-channel network port module, a multi-channel optical port module, two signal isolation modules, and a CPU module; The multi-channel RS485 input module is connected to the RS485 output of the hub to receive digital signals of gas temperature, pressure and density information; The two signal isolation modules are configured as follows: one signal isolation module is used to isolate the RS485 module signal from the CPU module, and the other signal isolation module is used to isolate the network port module signal, the optical port module signal from the CPU module. The processor converts the received multiple RS485 signals into a standard communication protocol and then outputs them to the monitoring backend through a network port module or an optical port module.

7. A gas density status monitoring system for medium-voltage switchgear as described in claim 1, characterized in that, The monitoring backend enables the display of monitoring data and system control functions.

8. A gas density status monitoring system for medium-voltage switchgear as described in claim 1, characterized in that, The display module is embedded in the switch cabinet panel.

9. A gas density status monitoring system for medium-voltage switchgear as described in claim 1, characterized in that, The RS485 hub is mounted on a DIN rail and is centrally mounted on the standard DIN rail of the communication cabinet.

10. A gas density status monitoring system for medium-voltage switchgear as described in claim 1, characterized in that, The intelligent IED4 is installed inside the communication cabinet using either a rail or rack mounting method.

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