Intelligent on-line monitoring system for operating state of high-voltage fuse

Abstract

The utility model relates to the field of electrical equipment state monitoring, in particular to an intelligent on-line monitoring system for the running state of a high-voltage fuse. The system comprises a state acquisition sensor, a running state intelligent on-line monitoring device and a background system. The state acquisition sensor is used for acquiring a current signal of the fuse; the current and voltage signals are transmitted to an intelligent online operation state monitoring device through a wireless module, and after the fuse is abnormal, the intelligent online operation state monitoring device judges whether the fuse is normal, damaged or fused in combination with the collected current and voltage signals in the fault process; and the state information of the fuses is locally displayed and alarmed through a state indicating lamp, or is respectively forwarded and transmitted to a background system through an RS-485 communication interface in a wired manner. The states of all the high-voltage fuses in the station can be visually displayed in the background system, and the specific positions of the abnormal fuses can be positioned through the monitoring picture information of the background system, so that the operation and maintenance personnel can find and handle the abnormal fuses in time.

Description

Technical Field

[0001] The utility model relates to real-time status monitoring of electrical equipment in an electric power system, in particular to an intelligent online monitoring system for the operating status of a high-voltage fuse. Background Art

[0002] Fuse is the main one-time protection element in the power system and is often connected in series in the circuit of electrical equipment. When the current exceeds the specified value, the heat generated in the fuse will cause the fuse to melt and disconnect the circuit to achieve short circuit or overcurrent protection. It is one of the most commonly used protection devices.

[0003] However, in the high-voltage PT circuit, the fuse may be normally blown due to long-term overload operation, or the fuse and the filler may be in a high-resistance state due to the high temperature.

[0004] After the fuse is in a high-resistance state, the PT secondary voltage will change. If the voltage is less than the PT disconnection alarm value of the protection device, the protection device can send out an alarm signal; if the PT secondary voltage is less than the rated value and greater than the PT disconnection alarm value of the protection device, this abnormal operation will cause the low-voltage related protection in the power supply system to malfunction, and will also cause metering errors in the metering system, directly causing economic losses; at the same time, the inspection and replacement of abnormal fuses need to be checked one by one, which consumes time and manpower and is inconvenient to use.

[0005] In view of the above situation, there is currently no similar monitoring device or method to conduct online monitoring of its operating status. It is mainly through manual inspection. If the fuse has a melting abnormality, it cannot be discovered in time, and the operating status of the fuse cannot be grasped in real time.

[0006] As users' requirements for power supply quality increase, whether power supply equipment can operate safely and reliably has become a key assessment indicator of power supply quality. Therefore, this paper studies the problem that the fuse may be in a high-resistance state, and theoretically analyzes the causes and characteristics of PT fuse abnormalities. Through signal detection and communication technology, the position of the abnormal fuse can be accurately located, and the problem can be discovered quickly and timely, so as to respond quickly and achieve fixed-point replacement, solve the lag and false alarm problems of traditional monitoring, and effectively ensure the safe operation of electrical equipment in the power system. Utility Model Content

[0007] The utility model aims to provide an intelligent online monitoring system for the operation status of a high-voltage fuse, which can facilitate the staff to timely know the status of the fuse and promptly repair and replace the fuse when a fault occurs.

[0008] A single intelligent online monitoring device for operating status in the system performs internal analysis and processing based on the collected data information, and displays the results locally; multiple intelligent online monitoring devices for operating status use RS-485 wired communication to transmit data to the background system, thereby achieving real-time online monitoring of the operating status of multiple fuses.

[0009] The specific technical solution adopted by the utility model is:

[0010] An intelligent online monitoring system for the operating status of a high-voltage fuse; comprising a "status acquisition sensor" installed in series at the lower end of the fuse to record sudden changes in current flowing through the fuse, an "intelligent online monitoring device for operating status" for local display, and a remote "backstage system".

[0011] The status acquisition sensor is located at the connection between the fuse and the grounding flat body below. There are fixing screws on the front and back of the status acquisition sensor, and a wireless module is installed at the bottom. The status acquisition sensor adopts inductive power acquisition technology, with fast frequency response, large acquisition range, high measurement accuracy, short measurement cycle and data upload time. Through low-power chips, high-speed 16-bit AD converters, and signal filtering circuits, it can quickly and accurately capture the current flowing through the fuse under various operating conditions. When current passes through the status acquisition sensor, the internal magnet will generate a magnetic field, and the magnetic field will act on the winding to generate a voltage signal. The amplitude of this voltage signal is proportional to the current flowing through the fuse; at the same time, the voltage signal is converted by the electronic circuit into a digital signal that can represent the actual current flowing through the fuse, and is transmitted to the "operation status intelligent online monitoring device" in the interval through the wireless module and the ISM wireless network.

[0012] The intelligent online monitoring device for operating status is located in the corresponding interval of the monitored fuse. The front of the intelligent online monitoring device for operating status is fixed with an LCD display screen, a status indicator light, and a human-machine interaction part for key input. The input end of the power module of the intelligent online monitoring device for operating status is electrically connected to the output end of the power supply used on site. The input end of the PT secondary voltage signal acquisition circuit in the intelligent online monitoring device for operating status is electrically connected to the output end of the external PT secondary voltage signal terminal. The intelligent online monitoring device for operating status receives the converted current signal transmitted from the status acquisition sensor through the wireless data transceiver module, and combines the secondary voltage signal collected from the PT secondary circuit. After calculation and comparison by the internal operation module, the operating status of the fuse is comprehensively and accurately evaluated. The output end of the RS-485 communication interface inside the intelligent online monitoring device for operating status is electrically connected to the communication input end of the background system, and transmitted through wired communication.

[0013] The utility model has the following advantages:

[0014] The utility model, an intelligent online monitoring system for the operating status of high-voltage fuses, promotes the intelligent monitoring and management of electrical equipment. At the same time, combined with the existing wireless communication technology, it can achieve real-time monitoring of the operating status of fuses at any time and any place. Compared with the current situation, the advantages are as follows:

[0015] Supports real-time display of high-voltage fuse operating status locally or remotely;

[0016] The background system summarizes and displays the data of multiple intelligent online monitoring devices for operating status, and determines whether the fuse is in normal state, blown state, or high resistance state. When the state is abnormal, the system screen will issue an alarm prompt;

[0017] The combination of wired and wireless communications enables a single system platform to centrally monitor the operating status of multiple fuses in multiple locations;

[0018] The status acquisition sensor uses inductive power supply technology and is not restricted by the power supply location;

[0019] The state acquisition sensor uses micro-power processors and low-power components to reduce power consumption, and adopts deep sleep and adaptive dynamic frequency adjustment;

[0020] The status acquisition sensor and the intelligent online monitoring device for the operating status adopt wireless transmission, which effectively avoids the potential safety hazards caused by the direct connection of high and low voltage electrical equipment.

[0021] The state acquisition sensor and the intelligent online monitoring device for the operating state use the appropriate wireless communication frequency band, which is not affected by the shielding of the metal distribution cabinet and has strong anti-interference ability;

[0022] The installation is convenient and flexible, the circuit is simple, and it is easy to install and modify; making the system run safely and reliably. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is an overview diagram of an intelligent online monitoring system for the operating status of a high-voltage fuse in the utility model;

[0024] Figure 2 This is the principle block diagram of the state acquisition sensor of the utility model;

[0025] Figure 3 This is a principle block diagram of the intelligent online monitoring device for operating status of the utility model.

[0026] Description of reference numerals: 1-status acquisition sensor, 2-operation status intelligent online monitoring device, 3-backend system;

[0027] 101-MCU, 102-current sensor, 103-signal filtering circuit, 104-signal amplifying circuit, 105-signal sampling, 106-data operation, 107-power management, 108-communication control, 109-wireless module;

[0028] 201-CPU, 202-wireless communication module, 203-RS-485 communication interface, 204-SOE data storage module, 205-logic judgment, 206-power module, 207-alarm module, 208-PT secondary voltage signal acquisition circuit, 209-human-computer interaction. DETAILED DESCRIPTION

[0029] The present invention is described in detail below in conjunction with specific implementation methods.

[0030] The background system in the utility model is based on the SCADA system, which is a computer-based automation system, and is only used for monitoring and multi-point centralized display of information collected by the intelligent online monitoring device for the operating status, as well as alarming for abnormal status of the fuse. The intelligent online monitoring system in the utility model is a hardware platform composed of various physical components connected together through line structures, and can be used in conjunction with software of existing technologies, but the software that cooperates with this system is not an innovative part of the utility model.

[0031] An overview of an intelligent online monitoring system for the operation status of high-voltage fuses is shown in the figure below: Figure 1 As shown, it includes 1 state acquisition sensor installed at the end of the high-voltage fuse, 2 operating state intelligent online monitoring device in the interval and 3 background system.

[0032] The principle block diagram of the state acquisition sensor is as follows: Figure 2 As shown, the current sensor 102 collects the current information flowing through the fuse monitoring point and transmits it to the signal filtering circuit 103 to filter the signal, eliminate the noise influence, and improve the signal-to-noise ratio. The signal is then adjusted by the signal amplification circuit 104 to improve the signal strength and enhance the transmission capacity. The effective current signal after filtering and amplification is sent to the signal sampling 105, sampled according to the selected sampling frequency, and the sampling result is stored and quantized into a digital signal. After the digital signal is processed by the data operation 106 in the 101 MCU, the signal is transmitted to the local intelligent online monitoring device of the operating status through the ISM wireless network through the 2.4 GHz communication frequency band selected by the wireless module 109 under the control of the communication 108; wherein the 101 MCU adopts the PIC16F886-E / SO chip, and the model of the wireless module 109 is AS01-ML01DPS.

[0033] The sensor draws power by induction and uses 107 power management. It can effectively control the power consumption of circuits and modules in the status acquisition sensor, reasonably allocate the power used in various parts such as signal acquisition and communication transmission, and achieve real-time transmission of micro-power data; the current sensor is combined with high-speed sampling technology to quickly and accurately capture data information of the fuse in normal, high-resistance and blown working states and quickly upload it.

[0034] The principle block diagram of the intelligent online monitoring device for operating status is as follows: Figure 3 As shown, the device includes 201 CPU module, 202 wireless communication module, 203 RS-485 communication interface, 204 SOE data storage module, 205 logic judgment, 206 power module, 207 alarm module, 208 PT secondary voltage signal acquisition circuit, 209 human-computer interaction, and 201 CPU module adopts STC11L60XE high-speed and low-power chip.

[0035] Under the control of 201CPU, the data collected by 208PT secondary voltage signal acquisition circuit is transmitted to 201CPU for storage and calculation processing;

[0036] The data information received by the wireless communication module 202 from the status acquisition sensor is transmitted to the CPU 201 for storage and calculation processing;

[0037] The 204SOE data storage module records and stores device monitoring data, historical alarms, fault information, device setting parameters, etc.

[0038] 209 Human-computer interaction (status indicator light, LCD display, key input) can view and browse the internal data information of the device, and provide settings for the internal parameters of the device;

[0039] 205 logic judgment performs logic judgment and comparison on the current and voltage information collected and received by the 202 wireless communication module and the 208PT secondary voltage signal collection circuit and the internal setting parameter range;

[0040] 207 alarm module displays information and alarms on abnormal data of fuse;

[0041] The communication part of the intelligent online monitoring device for operating status includes a 202 wireless communication module and a 203 RS-485 communication interface, which is connected to the background system through the 203 RS-485 communication interface for data interaction, and the monitoring information in the intelligent online monitoring device for operating status is uploaded to the background system, and the relevant operations and information issued by the background system are received at the same time;

[0042] The intelligent online monitoring device for the operating status is wirelessly connected to the status acquisition sensor through the 202 wireless communication module, receives the primary current signal of the fuse and the secondary voltage signal of the PT, and isolates, filters, amplifies, and converts the original voltage and current signals, and then outputs them to the 201CPU. According to the extracted voltage and current signal characteristic information, it is analyzed and identified to determine whether the fuse is normal, and the status indicator light makes a preliminary display of the judgment result, and the sampled data is displayed in detail on the LCD screen, or the processed judgment result and sampled data are transmitted to the 3 background system through the 203RS-485 communication interface for real-time display. If the set domain value is exceeded, the data can be displayed and alarmed on the device on-site or in the remote background through the 207 alarm module, thereby achieving online monitoring of the operating status of the high-voltage fuse.

[0043] The utility model discloses an intelligent online monitoring system for the operation status of a high-voltage fuse, which adopts a current and voltage dual detection technology, and monitors the primary-side current flowing through the fuse and the PT secondary-side voltage under energized conditions, thereby obtaining information on whether the fuse is in a normal, high-resistance, or blown state, thereby achieving real-time online monitoring of the operation status of the fuse, and issuing an alarm in a timely manner when an abnormal operation occurs, thereby ultimately ensuring the safe, reliable, and stable operation of the power supply system.

[0044] The content of the utility model is not limited to the examples listed, and any equivalent changes made to the technical solution of the utility model by ordinary technicians in this field after reading the specification of the utility model are covered by the claims of the utility model.

Claims

1. An intelligent online monitoring system for the operating status of a high-voltage fuse, characterized in that: A high-voltage fuse operating state intelligent online monitoring system comprises a "state acquisition sensor (1)", an "operating state intelligent online monitoring device (2)", and a "backstage system (3)". The state acquisition sensor (1) is located at the connection between the fuse and the lower grounding flat body, and the state acquisition sensor (1) has fixing screws at the front and rear. The state acquisition sensor (1) internally comprises a current sensor (102), a signal filtering circuit (103), a signal amplification circuit (104), a power management (107), an MCU (101), and a wireless module (109) installed at the bottom of the state acquisition sensor (1) and wirelessly connected to the operating state intelligent online monitoring device (2). The current sensor (102) collects current information of the fuse and transmits it to a signal filtering and amplifying circuit, the circuit is connected to an MCU (101), and the MCU (101) is respectively connected to a signal sampling (105), a data operation (106), and a communication control (108); The intelligent online monitoring device (2) for operating status is located in the corresponding interval of the monitored fuse. An LCD display screen, a status indicator light, and a human-machine interaction part (209) for key input are fixed on the front of the intelligent online monitoring device (2). The input end of the power module (206) of the intelligent online monitoring device (2) for operating status is electrically connected to the output end of the power supply used on site. The input end of the PT secondary voltage signal acquisition circuit (208) in the intelligent online monitoring device (2) for operating status is electrically connected to the output end of the external PT secondary voltage signal terminal. The output end of the internal RS-485 communication interface (203) of the intelligent online monitoring device for operating status is electrically connected to the communication input end of the background system (3) for transmission via wired communication.

2. The intelligent online monitoring system for the operation status of a high-voltage fuse according to claim 1 is characterized in that: An intelligent online operating status monitoring device (2) in an intelligent online operating status monitoring system for a high-voltage fuse is electrically non-connected to a status acquisition sensor (1), and data is interactively transmitted via an ISM wireless network; The power supply of the state acquisition sensor (1) is inductively powered, and the state acquisition sensor (1) is connected to a power management (107) using a low-power MCU chip (101) to reasonably distribute energy for the signal amplification circuit (104), signal sampling (105), data operation (106) and wireless module (109) in the state acquisition sensor (1).

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