CN115133653A

CN115133653A - Monitoring system

Info

Publication number: CN115133653A
Application number: CN202210743958.4A
Authority: CN
Inventors: 宫艳朝; 董宇; 胡文东; 刘渝辉; 杨海运
Original assignee: State Grid Corp of China SGCC; Handan Power Supply Co of State Grid Hebei Electric Power Co Ltd
Current assignee: State Grid Corp of China SGCC; Handan Power Supply Co of State Grid Hebei Electric Power Co Ltd
Priority date: 2022-06-28
Filing date: 2022-06-28
Publication date: 2022-09-30

Abstract

The application provides a monitoring system through thereby set up wireless sensor real-time supervision protection device and acquire the information relevant with protection device in protection device below, then with the information transmission who is relevant with protection device to receiving arrangement, thereby send this information to electronic equipment in order to realize staff's real-time supervision to protection device through receiving arrangement.

Description

Monitoring system

Technical Field

The application relates to the technical field of monitoring systems, in particular to a monitoring system.

Background

At present, the gradual popularization of clean energy power generation, distributed power sources and micro-grids increases the reactive fluctuation of the operation of a power distribution network, in order to ensure the balance of each reactive power of the system, frequent switching needs to be carried out on reactive equipment, and each part of the distributed energy is protected by a protection device.

Disclosure of Invention

The present application is proposed to solve the above-mentioned technical problems. The embodiment of the application provides a monitoring system, and the problem that the state of a protection device cannot be monitored is solved.

According to an aspect of the present application, there is provided a monitoring system comprising:

a capacitor bank including a plurality of first capacitors connected in parallel with each other;

the reactor group comprises a plurality of reactors which are electrically connected with the first capacitors respectively;

a parallel component comprising a resistor and a second capacitor, the resistor and the second capacitor being connected in parallel;

a protection device in series with the parallel assembly to form a series assembly; wherein the series connection components comprise a plurality of series connection components, each series connection component is connected with each first capacitor in series, and the protection device is used for protecting the capacitor bank;

a switch assembly connected in series with each of the first capacitors; the wireless sensor is arranged at the bottom of the protection device and is in communication connection with the protection device, and the wireless sensor is used for sending information related to the protection device; and

and the receiving device is in communication connection with the wireless sensor and is used for receiving the information related to the protection device and sending the information to the electronic equipment. The wireless sensor is arranged below the protection device, so that the protection device is monitored in real time, information related to the protection device is acquired, and then the information related to the protection device is sent to the receiving device, so that the information is sent to the electronic equipment through the receiving device to realize real-time monitoring of workers on the protection device.

In one embodiment, the wireless sensor includes a counting sensor for counting the number of transmissions when the wireless sensor transmits a message. The counting sensor can accurately count the number of times of the messages sent by the wireless sensor.

In one embodiment, the wireless sensor includes a pulse circuit communicatively coupled to the counting sensor, the pulse circuit configured to record a number of discharge events of the protection device. The number of times of the discharge operation of the protection device can be accurately recorded by the pulse circuit.

In one embodiment, the wireless sensor includes a detection device electrically connected to a battery of the wireless sensor, and the detection device is configured to detect a performance of the battery. Can accurate performance that detects the battery through detection device to make things convenient for the operation personnel to monitor the performance of battery, prevent the damage of battery and lead to the holistic destruction of monitoring system.

In an embodiment, the wireless sensor includes a current sensor electrically connected to the battery, and the current sensor is configured to detect a current of the battery. The current of the battery is detected through the current sensor so as to monitor the state of the battery in real time.

In one embodiment, the wireless sensor includes a sampling circuit for collecting information related to the protection device. The sampling circuit can accurately collect the information related to the protection device.

In one embodiment, the wireless sensor includes an amplifying circuit communicatively coupled to the sampling circuit, the amplifying circuit configured to amplify a current corresponding to the transmission of the information associated with the protection device. The current corresponding to the information related to the protection device is amplified by the amplifying circuit,

in one embodiment, the receiving device includes a display circuit for displaying information related to the protection device. The display circuit can display the related information of the protection device, so that a user can conveniently monitor the state of the protection device in real time.

In an embodiment, the receiving device comprises a waterproof antenna for communicative connection with the wireless sensor. Can be connected with wireless sensor communication through waterproof antenna to can be quick with information transmission to receiving arrangement.

In an embodiment, the receiving device includes a 5G communication module, a 4G communication module, a 3G communication module, or a 2G communication module, the 5G communication module, the 4G communication module, the 3G communication module, or the 2G communication module is connected to the waterproof antenna, and the 5G communication module, the 4G communication module, the 3G communication module, or the 2G communication module is configured to receive information related to the protection device sent by the waterproof antenna. Information can be rapidly transmitted through the 5G communication module, the 4G communication module, the 3G communication module or the 2G communication module.

The application provides a monitoring system, includes: the device comprises a capacitor bank, a reactor bank, a parallel component, a protection device, a switch component, a wireless sensor and a receiving device, wherein the capacitor bank comprises a plurality of first capacitors which are connected in parallel, each first capacitor is connected in parallel, the reactor bank comprises a plurality of reactors which are respectively electrically connected with the first capacitors, the parallel component comprises a resistor and a second capacitor, the resistor and the second capacitor are connected in parallel, the protection device is connected with the parallel component in series to form a series component, the series component comprises a plurality of reactors which are respectively connected in parallel, each series component is connected with each first capacitor in series, the protection device is used for protecting the capacitor bank, the switch component is connected with each first capacitor in series, the wireless sensor is arranged at the bottom of the protection device, the wireless sensor is in communication connection with the protection device, and the wireless sensor is used for sending information related to the protection device, the receiving device is in communication connection with the wireless sensor and is used for receiving information related to the protection device and sending the information to the electronic equipment. The wireless sensor is arranged below the protection device, so that the protection device is monitored in real time, information related to the protection device is acquired, and then the information related to the protection device is sent to the receiving device, so that the information is sent to the electronic equipment through the receiving device, and real-time monitoring of workers on the protection device is achieved.

Drawings

The above and other objects, features and advantages of the present application will become more apparent by describing in more detail embodiments of the present application with reference to the attached drawings. The accompanying drawings are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings, like reference numbers generally represent like parts or steps.

Fig. 1 is a schematic structural diagram of a monitoring system according to an exemplary embodiment of the present application.

Fig. 2 is a schematic structural diagram of a wireless sensor provided in an exemplary embodiment of the present application.

Fig. 3 is a schematic structural diagram of a wireless sensor according to another exemplary embodiment of the present application.

Fig. 4 is a schematic structural diagram of a wireless sensor provided in another exemplary embodiment of the present application.

Fig. 5 is a schematic structural diagram of a wireless sensor according to another exemplary embodiment of the present application.

Fig. 6 is a schematic structural diagram of a wireless sensor provided in another exemplary embodiment of the present application.

Fig. 7 is a schematic structural diagram of a wireless sensor according to another exemplary embodiment of the present application.

Fig. 8 is a schematic structural diagram of a receiving apparatus according to an exemplary embodiment of the present application.

Fig. 9 is a schematic structural diagram of a receiving apparatus according to another exemplary embodiment of the present application.

Detailed Description

Hereinafter, example embodiments according to the present application will be described in detail with reference to the accompanying drawings. It should be apparent that the described embodiments are only a few embodiments of the present application, and not all embodiments of the present application, and it should be understood that the present application is not limited to the example embodiments described herein.

Fig. 1 is a schematic structural diagram of a monitoring system according to an exemplary embodiment of the present application. As shown in fig. 1, the monitoring system includes: a capacitor bank 11, a reactor bank 12, a parallel assembly 13, a protection device 14, a switch assembly 15, a wireless sensor 16 and a receiving device 17, wherein the capacitor bank 11 comprises a plurality of first capacitors 111, each first capacitor 111 is connected in parallel, the reactor bank 12 comprises a plurality of reactors 121, each reactor 121 is electrically connected with each first capacitor 111, the parallel assembly 13 comprises a resistor and a second capacitor, the resistor and the second capacitor are connected in parallel to form the parallel assembly 13, the protection device 14 is connected in series with the parallel assembly 13 to form a series assembly, wherein each series assembly is connected in parallel with each reactor, each series assembly is connected in series with each first capacitor 111, the protection device 14 is used for protecting the capacitor bank 12, the switch assembly 15 is connected in series with each first capacitor 111, the wireless sensor 16 is arranged at the bottom of the protection device 14, the wireless sensor 16 is connected in communication with the protection device 14, the wireless sensor 16 is used for sending information related to the protection device 14, the receiving device 17 is in communication connection with the wireless sensor 16, and the receiving device 17 is used for receiving the information related to the protection device 14 and sending the information to the electronic equipment.

The protection device 14 may be an SCLP, the wireless sensor 16 may be a 433 mhz wireless sensor, and the receiving device 17 employs a wireless communication technology, which may be 4G or 5G, etc. The wireless sensor 16 is arranged at the lower end of the protection device 14 and is responsible for processing, adopting and calculating the leakage current, the discharge rush current and the signals of the built-in disconnector of the protection device 14, and then sending the data to the receiving device 17 through 433 MHz wireless signals, and the receiving device 17 is arranged in a transformer substation so as to receive the data. The receiving device 17 receives the data to analyze and detect the data. The receiving device 17 can be connected to an electronic device, the receiving device 17 receives information related to the protection device 14, analyzes and troubleshooting the information, and if the protection device 14 fails through analysis, the receiving device 17 generates information containing the failure of the protection device 14 and sends the information to the electronic device, and the electronic device can be a mobile phone, a tablet computer, an intelligent (desktop or portable) computer and the like. The receiving device 17 may be provided as a portable device, and the receiving device 17 may be attached to the electronic apparatus. The receiving device 17 can also be placed in a stainless steel instrument box, the box body is fixed in the open area of the transformer substation, and the receiving device 17 can be connected with a power line so as to supply power to the receiving device 17 through the power line. Structural features of the protection device 14: the volume is simple and small, the installation is convenient, and the construction is convenient; the action is reliable: the overvoltage multiple can be limited to 1.83 times, and the overvoltage generated under various abnormal working conditions can be effectively limited; long service life of the standby operation: the voltage born under the normal operation working condition is extremely low, so that the service life of the overvoltage protector is greatly prolonged; the self protection measures are perfect: the built-in self-protection release device ensures that the protector can be quickly released from the system under the most adverse conditions (such as the occurrence of inter-electrode breakdown of the capacitor). The safety of the electric equipment is protected while the electric equipment is protected; the record is complete: the online monitoring system is matched, so that the action record and the current and voltage amplitude of the protector can be recorded, and the inquiry and the fault analysis are facilitated; the adaptability to the field environment is high: the overvoltage protector can be suitable for various environments indoors and outdoors. The status of the protection device 14 can be remotely checked by means of the receiving device 17. The wireless sensor 16 can transmit power information, frequency information and the like of the protection device 14 to the receiving device 17, the receiving device 17 integrates the power of the protection device 16, the power of the protection device 16 is sequenced according to the time sequence, a preset power threshold value is set, and a time interval corresponding to the power exceeding the preset power threshold value is determined, so that an operator can conveniently determine which time interval the protection device has a problem. The function of the series capacitor: the method can inhibit the over-current of the capacitor group during closing, inhibit higher harmonics, inhibit the over-current of two-phase reignition and three-phase reignition during opening of the capacitor group, facilitate arc extinction, and limit the short-circuit capacity of the capacitor group due to the short-circuit discharge current of other capacitor groups during the inter-electrode fault of one capacitor group. The capacitor bank comprises a plurality of first capacitors, each first capacitor is connected in parallel, the reactor bank comprises a plurality of reactors, each reactor is electrically connected with each first capacitor, the parallel component comprises a resistor and a second capacitor, the resistor and the second capacitor are connected in parallel to form a parallel component, the protection device is connected in series with the parallel component to form a series component, the protection device comprises a protection device, a switch assembly, a wireless sensor, a receiving device and an electronic device, wherein each series assembly is connected with each reactor in parallel, each series assembly is connected with each first capacitor in series, the protection device is used for protecting a capacitor bank, the switch assembly is connected with each first capacitor in series, the wireless sensor is arranged at the bottom of the protection device and is in communication connection with the protection device, the wireless sensor is used for sending information related to the protection device, the receiving device is in communication connection with the wireless sensor, and the receiving device is used for receiving the information related to the protection device and sending the information to the electronic device.

The application provides a monitoring system, includes: the device comprises a capacitor bank, a reactor bank, a parallel component, a protection device, a switch component, a wireless sensor and a receiving device, wherein the capacitor bank comprises a plurality of first capacitors which are connected in parallel, each first capacitor is connected in parallel, the reactor bank comprises a plurality of reactors which are respectively electrically connected with the first capacitors, the parallel component comprises a resistor and a second capacitor, the resistor and the second capacitor are connected in parallel, the protection device is connected with the parallel component in series to form a series component, the series component comprises a plurality of reactors which are respectively connected in parallel, each series component is connected with each first capacitor in series, the protection device is used for protecting the capacitor bank, the switch component is connected with each first capacitor in series, the wireless sensor is arranged at the bottom of the protection device, the wireless sensor is in communication connection with the protection device, and the wireless sensor is used for sending information related to the protection device, the receiving device is in communication connection with the wireless sensor and is used for receiving information related to the protection device and sending the information to the electronic equipment. The wireless sensor is arranged below the protection device, so that the protection device is monitored in real time, information related to the protection device is acquired, and then the information related to the protection device is sent to the receiving device, so that the information is sent to the electronic equipment through the receiving device to realize real-time monitoring of workers on the protection device.

Fig. 2 is a schematic structural diagram of a wireless sensor provided in an exemplary embodiment of the present application. As shown in fig. 2, the wireless sensor 16 includes a count sensor 161, and the count sensor 161 is used to count the number of transmissions when the wireless sensor 16 transmits a message.

Fig. 3 is a schematic structural diagram of a wireless sensor according to another exemplary embodiment of the present application. As shown in fig. 3, the wireless sensor 16 includes a pulse circuit 162, the pulse circuit 162 is connected to the counter sensor 161 in communication, and the pulse circuit 162 is used to record the number of discharge operations of the protection device 14.

The pulse circuit 162 can ensure that the discharge operation of the protection device 14 is not missed or miscounted.

Fig. 4 is a schematic structural diagram of a wireless sensor provided in another exemplary embodiment of the present application. As shown in fig. 4, the wireless sensor 16 includes a detecting device 163, the detecting device 163 is electrically connected to the battery 164 of the wireless sensor 16, and the detecting device 163 is used for detecting the performance of the battery 164.

The detection device 163 can detect the performance of the battery 164 in real time, and can prompt a worker to replace the battery when the function of the battery 164 is exhausted.

Fig. 5 is a schematic structural diagram of a wireless sensor provided in another exemplary embodiment of the present application. As shown in fig. 5, the wireless sensor 16 includes a current sensor 165, the current sensor 165 is electrically connected to the battery 164, and the current sensor 165 is used for detecting the current of the battery 164.

The battery 164 may be connected to a temperature sensor that may detect the temperature of the battery 164 in real time, with the operating temperature of the battery 164 ranging from-40 degrees celsius to 85 degrees celsius. An alarm device is connected to the temperature sensor, and the alarm device can alarm the abnormal temperature of the battery 164. The temperature sensor sends the temperature of the battery 164 to the receiving device 17 through the wireless sensor 16, the receiving device 17 integrates the temperature of the battery 164, the temperature of the battery 164 is arranged according to the time sequence, the temperature of the battery 164 exceeding a preset temperature threshold value is marked, the preset temperature threshold value can be 85 degrees centigrade, if the temperature exceeding the preset temperature threshold value in a preset number within a detection time period is detected, alarm information is sent to the electronic equipment, and the preset number can be 3.

Fig. 6 is a schematic structural diagram of a wireless sensor provided in another exemplary embodiment of the present application. As shown in fig. 6, the wireless sensor 16 includes a sampling circuit 166, and the sampling circuit 166 is used to collect information related to the protection device 14.

The sampling circuit has an analog signal input, a control signal input, and an analog signal output. The circuit functions to receive an input voltage at a given time and hold the voltage at the output until the next sampling begins. The sampling circuit is usually composed of an analog switch, a holding capacitor and a non-inverting circuit with a unit gain of 1. The sampling operates in one of two states, a sample state and a hold state. In the sampling state, the switch is turned on, which tracks the level change of the analog input signal as fast as possible until the arrival of the hold signal; in the hold state, the switch is opened and the tracking process is stopped, which keeps the instantaneous value of the input signal until the switch is opened.

Fig. 7 is a schematic structural diagram of a wireless sensor according to another exemplary embodiment of the present application. As shown in fig. 7, the wireless sensor 16 includes an amplifier circuit 167, the amplifier circuit 167 is communicatively connected to the sampling circuit 166, and the amplifier circuit 167 is configured to amplify a current corresponding to the information related to the 14 protection devices.

The wireless sensor 16 is internally provided with a low-power consumption MCU, and the low-power consumption MCU is connected with a watchdog to monitor the low-power consumption MCU in real time.

The wireless sensor can also monitor the battery capacity, the working time of the battery, the working power consumption, the discharge count value, the leakage current measurement range and precision and the like. Respectively constructing the battery capacity and the battery working time into curves, marking the time in each monitoring process, and if the battery capacity is smaller than a preset battery capacity threshold value and the battery working time is longer than a preset working time, marking the corresponding battery capacity so as to stop the discharge of the battery.

Fig. 8 is a schematic structural diagram of a receiving apparatus according to an exemplary embodiment of the present application. As shown in fig. 8, the receiving device 17 includes a display circuit 171, and the display circuit 171 is used to display information related to the protection device 14.

The receiving device 17 comprises a display circuit 171, the display circuit 171 can be an OLED display screen or an LCD display screen, if the receiving device 17 is placed in a stainless steel instrument box, the display circuit 171 can be displayed on the surface of the instrument box, and the display circuit 171 can display information related to the protection device 14, so that the information is convenient for a worker to look up. In addition, the receiving device 17 further includes a key device, which can adjust data displayed on the display screen and also can control the display circuit 171 to be turned on or turned off through the key device.

Fig. 9 is a schematic structural diagram of a receiving apparatus according to another exemplary embodiment of the present application. As shown in fig. 9, the receiving device 17 includes a waterproof antenna 172, and the waterproof antenna 172 is used for communication connection with the wireless sensor 16.

In an embodiment, the receiving device includes a 5G communication module, a 4G communication module, a 3G communication module, or a 2G communication module, the 5G communication module, the 4G communication module, the 3G communication module, or the 2G communication module is connected to the waterproof antenna, and the 5G communication module, the 4G communication module, the 3G communication module, or the 2G communication module is configured to receive information related to the protection device sent by the waterproof antenna.

The 5G communication module or the 4G communication module or the 3G communication module or the 2G communication module is connected with a waterproof antenna, and the waterproof antenna is a 4G waterproof antenna. The receiving device 17 further comprises a wireless module, the wireless module is a 433 mhz wireless module, and the 433 mhz wireless module is in communication connection with the 433 mhz waterproof antenna.

In addition, the receiving device can be connected with the electronic equipment or a server in communication connection, the server comprises a database server and a network server, and the receiving device can receive an access request of a user and can also store data uploaded by the monitoring system in a database. Because the webpage is used as a data viewing mode, various computers, tablets, mobile phones and other equipment adopting operating systems such as Windows, Android, iOS and the like can remotely access data by using a webpage browser. The data can be checked in different modes such as real-time data, historical data and the like, displayed in different forms such as tables, graphs and the like, and can also be exported to be Excel tables or pictures for convenient secondary use. The viewing authority of the data can be defined differently according to the transformer substation, the equipment and the unit. In addition, the prompting short message can be sent to the appointed mobile phone number regularly or in case of any condition.

The monitoring system may further include: the fuse is connected in parallel with the parallel assembly. When the capacitor bank generates overvoltage, the overvoltage firstly flows to the protection device, and if the protection device fails, the fuse can absorb energy to protect the capacitor bank. The monitoring system may further include a zinc oxide device connected in series with the fuse, the zinc oxide device being connected in parallel with the parallel assembly. If the fuse can not protect the capacitor bank, the energy can be absorbed by the zinc oxide device. The monitoring system may further include a driving component electrically connected to the capacitor bank, the driving component receiving the overvoltage when the capacitor bank generates the overvoltage. The driving member may be a motor or the like. The monitoring system can also comprise a fan, wherein the fan is electrically connected with a driving part, and the driving part is used for driving the fan to rotate.

According to the volt-ampere characteristic of the arrester (zinc oxide device), the current flowing through the arrester under normal working voltage is very small and is in a high-resistance state. When the voltage rises, once the lightning arrester enters a breakdown region, the voltage is maintained at a certain level within a very wide current variation range, and the lightning arrester is in a low-resistance state. The surge arrester limits the overvoltage level according to this characteristic. The voltage level maintained by the arrester also has a volt-second characteristic. At the same current amplitude, the voltage level maintained by the lightning arrester increases as the wave head time decreases, and the smaller the wave head time, the more remarkable. The wave head time of the re-ignition overvoltage is far shorter than that of the interception overvoltage, and the capability of the lightning arrester for protecting the re-ignition overvoltage is obviously weakened. Different reactor inductance values, equivalent capacitors and lead wire inductance differences, and the lightning arrester also has different protection effects on the reactor inductance values, the equivalent capacitors and the lead wire inductance differences.

A fuse (fuse) is an electric device that fuses a fuse body by heat generated by itself when a current exceeds a predetermined value, thereby breaking an electric circuit. The fuse melts the melt by the heat generated by the fuse after the current exceeds a specified value for a period of time, so as to cut off the circuit; a current protector is made by applying the principle.

The fuse includes plug-in fuse, spiral fuse, closed fuse, fast fuse and from restoring the fuse, wherein:

plug-in fuse: it is commonly used at the end of lines with voltage levels of 380V and below as short-circuit protection for distribution branches or electrical equipment.

And (3) a spiral fuse: the upper end of the melt is covered with a fusing indicator, and once the melt is fused, the fusing indicator is ejected out and can be observed through a glass hole on a porcelain cap, which is commonly used in machine tool electrical control equipment. A spiral fuse. The breaking current is large, and the short-circuit protection circuit can be used in circuits with voltage class of 500V or below and current class of 200A or below for short-circuit protection.

A closed fuse: the closed fuse includes a filler fuse and a non-filler fuse. The filler fuse is generally a square ceramic tube, is filled with quartz sand and melt, has strong breaking capacity, and is used in circuits with voltage level below 500V and current level below 1 KA. The stuffing-free closed fuse has less breaking capacity, and may be used in power network or distribution equipment of 500V below and 600A below.

A fast fuse: the fast fuses are mainly used for short-circuit protection of semiconductor rectifying elements or rectifying devices. Since the overload capability of the semiconductor element is low. The short circuit protection is required to have the capability of blowing rapidly because it can only withstand a large overcurrent for a very short time. The fast fuse has basically the same structure as the filled closed fuse, but has different material and shape, and is a variable cross-section fuse with V-shaped deep groove punched by silver plate. The fast fuse is commonly called fast fuse for short, and is characterized by fast fusing speed, large rated current, strong breaking capacity, stable current limiting characteristic and small volume.

Self-resetting a fuse: the metallic sodium is used as a melt, and has high conductivity at normal temperature. When the short-circuit fault occurs in the circuit, the short-circuit current generates high temperature to quickly vaporize sodium, and the vaporous sodium presents a high resistance state, so that the short-circuit current is limited. When the short-circuit current disappears, the temperature drops, and the metal sodium recovers the original good conductive performance. The self-resetting fuse can only limit short-circuit current and cannot really break the circuit. Its advantages are no need of changing fused mass and reuse.

The fuse is mainly composed of a fuse element, a housing and a support 3, wherein the fuse element is a key element for controlling fusing characteristics. The material, size and shape of the melt determine the fusing characteristics. Melt materials fall into two categories, low melting point and high melting point. The low melting point materials such as lead and lead alloy have low melting point and are easy to fuse, and the section size of the prepared melt is larger due to larger resistivity, and more metal vapor is generated during fusing, so that the low melting point materials are only suitable for fuses with low breaking capacity. The high melting point materials such as copper and silver have high melting points and are not easy to fuse, but can be made into smaller section size than the low melting point melt due to lower resistivity, and the metal vapor generated during fusing is less, so the high melting point material is suitable for the fuse with high breaking capacity. The shape of the melt is divided into filament and ribbon. Changing the shape of the variable cross-section can significantly change the blowing characteristics of the fuse. The fuse has various fusing characteristic curves, and can be suitable for the requirements of different types of protected objects.

The action of the fuse is realized by fusing the melt, and the fuse has a very obvious characteristic, namely ampere-second characteristic.

For a melt, the action current and the action time characteristics of the melt, namely ampere-second characteristics of a fuse are also called inverse time delay characteristics, namely: the fusing time is long when the overload current is small; when the overload current is large, the fusing time is short.

Understanding ampere-second characteristics, we can see from joule's law that Q ═ I2 × R × T, in a series circuit, the R value of a fuse is basically unchanged, and the heat generation amount is proportional to the square of current I and proportional to the heat generation time T, that is to say: when the current is large, the time required for the melt to melt is short. When the current is small, the time for fusing the fuse is long, even if the heat accumulation speed is lower than the heat diffusion speed, the temperature of the fuse can not rise to the melting point, and the fuse can not fuse. Therefore, in a certain overload current range, when the current returns to normal, the fuse can not be fused and can be continuously used.

Thus, each melt has a minimum melting current. The minimum melting current is different for different temperatures. Although the current is influenced by the external environment, the current may not be considered in practical application. The ratio of the minimum fusing current of the melt to the rated current of the melt is generally defined as the minimum melting coefficient, and the melting coefficient of the common melt is more than 1.25, namely the melt with the rated current of 10A can not be fused when the current is less than 12.5A.

It can be seen from this that the fuse is excellent in short-circuit protection performance and general in overload protection performance. If it is to be used in overload protection, it is necessary to carefully match the line overload current to the fuse current rating. For example: the melt of 8A is used in a 10A circuit and is used for both short circuit protection and overload protection, but the overload protection characteristic is not ideal.

The fuse is selected mainly according to the protection characteristic of the load and the size of the short-circuit current. For motors and lighting branches with small capacities, fuses are often used as overload and short-circuit protection, so that a suitably small melt coefficient is desired. RQA series fuses of lead-tin alloy melts are typically used. For larger capacity motors and lighting mains, consideration should be given to short circuit protection and breaking capability. The RM10 and RL1 series fuses with high breaking capacity are usually selected; when the short-circuit current is large, the RT0 and RTl2 series fuses with the current limiting function are preferably adopted

The foregoing description has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit embodiments of the application to the form disclosed herein. While a number of example aspects and embodiments have been discussed above, those of skill in the art will recognize certain variations, modifications, alterations, additions and sub-combinations thereof.

Claims

1. A monitoring system, comprising: a capacitor bank including a plurality of first capacitors connected in parallel with each other; the reactor group comprises a plurality of reactors which are electrically connected with the first capacitors respectively; a parallel component comprising a resistor and a second capacitor, the resistor and the second capacitor being connected in parallel; a protection device in series with the parallel assembly to form a series assembly; wherein the series connection components comprise a plurality of series connection components, each series connection component is connected with each first capacitor in series, and the protection device is used for protecting the capacitor bank; a switch assembly connected in series with each of the first capacitors; the wireless sensor is arranged at the bottom of the protection device and is in communication connection with the protection device, and the wireless sensor is used for sending information related to the protection device; and the receiving device is in communication connection with the wireless sensor and is used for receiving the information related to the protection device and sending the information to the electronic equipment.

2. The monitoring system of claim 1, wherein the wireless sensor includes a counting sensor for counting the number of transmissions when the wireless sensor transmits a message.

3. The monitoring system of claim 2, wherein the wireless sensor includes a pulse circuit communicatively coupled to the counting sensor, the pulse circuit configured to record a number of discharge events of the protection device.

4. The monitoring system of claim 1, wherein the wireless sensor includes a detection device electrically connected to a battery of the wireless sensor, the detection device configured to detect a performance of the battery.

5. The monitoring system of claim 4, wherein the wireless sensor comprises a current sensor electrically connected to the battery, the current sensor configured to detect a current of the battery.

6. The monitoring system of claim 1, wherein the wireless sensor includes a sampling circuit for collecting information related to the protection device.

7. The monitoring system of claim 6, wherein the wireless sensor includes an amplification circuit communicatively coupled to the sampling circuit, the amplification circuit configured to amplify the current corresponding to the information associated with the protection device.

8. The monitoring system of claim 1, wherein the receiving device includes a display circuit for displaying information related to the protection device.

9. The monitoring system of claim 8, wherein the receiving device includes a waterproof antenna for communicative coupling with the wireless sensor.

10. The monitoring system according to claim 9, wherein the receiving device comprises a 5G communication module, a 4G communication module, a 3G communication module, or a 2G communication module, and the 5G communication module, the 4G communication module, the 3G communication module, or the 2G communication module is connected to the waterproof antenna and configured to receive the information related to the protection device sent by the waterproof antenna.