阅读说明：本技术 一种用于开关柜的温度在线监测与预警预测系统 (Temperature on-line monitoring and early warning prediction system for switch cabinet ) 是由 吴能成 朱浩琳 龙鑫宇 陈宇 林四敏 屈前 陈侨棠 林芳旭 黄冬梅 全叶盛 范耀 于 2020-11-20 设计创作，主要内容包括：本发明公开了一种用于开关柜的温度在线监测与预警预测系统,包括温度发送端、采集器和显示终端；所述的温度发送端安装在开关柜内部,主要由无线MCU、以及分别与无线MCU相连接的数字温度传感器、无线发射天线、感应取电模块和电流采集模块组成；所述的温度发送端通过无线发射天线与采集器进行无线数据传输；所述的采集器与显示终端通过GPRS通信网络进行数据传输。本发明结构简单、体积小、抗干扰能力强,实现了对温度的实时监测,利用温升预警综合判断算法和温升预测模型对早发现早处理,并对未来温升趋势进行预测判断未来故障发生可能性,进一步提高保护能力。(The invention discloses an on-line temperature monitoring and early warning prediction system for a switch cabinet, which comprises a temperature sending end, a collector and a display terminal, wherein the temperature sending end is connected with the collector; the temperature sending end is arranged in the switch cabinet and mainly comprises a wireless MCU, and a digital temperature sensor, a wireless transmitting antenna, an induction power taking module and a current acquisition module which are respectively connected with the wireless MCU; the temperature sending end carries out wireless data transmission with the collector through a wireless transmitting antenna; and the collector and the display terminal carry out data transmission through a GPRS communication network. The temperature monitoring system is simple in structure, small in size and strong in anti-interference capability, realizes real-time temperature monitoring, utilizes a temperature rise early warning comprehensive judgment algorithm and a temperature rise prediction model to perform early processing on early detection, predicts the future temperature rise trend and judges the possibility of future fault occurrence, and further improves the protection capability.)

1. A temperature on-line monitoring and early warning prediction system for a switch cabinet comprises a temperature sending end, a collector and a display terminal; the method is characterized in that: the temperature sending end is arranged in the switch cabinet and mainly comprises a wireless MCU, and a digital temperature sensor, a wireless transmitting antenna, an induction power taking module and a current acquisition module which are respectively connected with the wireless MCU; the temperature sending end carries out wireless data transmission with the collector through a wireless transmitting antenna; and the collector and the display terminal carry out data transmission through a GPRS communication network.

2. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 1, wherein: the collector comprises a data processing singlechip, and a wireless radio frequency receiving module, a memory, an alarm, a GPRS module and a display screen which are respectively connected with the data processing singlechip; the data processing single chip microcomputer is connected with the temperature sending end through the wireless radio frequency receiving module, receives temperature and current data transmitted by the temperature sending end and processes the data; the data processing single chip microcomputer transmits real-time data to the display terminal through the GPRS module; the memory is used for storing basic data information, including real-time temperature, historical temperature, current sampling data and basic information data; the alarm is used for carrying out temperature rise early warning and distinguishing different defect alarms and temperature rise prediction future fault alarms; the display screen is used for displaying basic data information and alarm information.

3. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 1, wherein: the display terminal is an Ipad or a mobile phone or a computer.

4. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in any one of claims 1 to 3, wherein: the digital temperature sensor adopts a DS18B20 patch; the current acquisition module adopts Rogowski coil for sampling and is magnetically saturated without an iron core; the induction electricity taking module is independent of the current collecting module, adopts an induction coil to take electricity, directly induces electromagnetic energy to obtain electric energy, and supplies power to the wireless MCU through filtering, rectifying and voltage stabilizing circuit; the wireless MCU is an ultra-low power consumption singlechip; the wireless transmitting antenna is a PCB antenna, and the anti-interference capability is enhanced by adopting copper-clad grounding treatment.

5. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 4, wherein: the temperature sending end also comprises a protective shell; the wireless MCU, the digital temperature sensor, the wireless transmitting antenna and the current acquisition module are respectively and fixedly arranged in the protective shell; the protective shell is provided with a groove for placing the boron nitride heat-conducting block, and the digital temperature sensor is tightly attached to the boron nitride heat-conducting block.

6. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 5, wherein: the protective casing is provided with a bandage through hole.

7. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 6, wherein: the temperature sending terminal be equipped with a plurality of, through steel ribbon fixed mounting respectively at the inside plum blossom contact of cubical switchboard, female arranging and cable joint department to set up different ID in order to distinguish different positions.

8. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 7, wherein: the induction electricity taking module comprises an induction coil, a rectification filter circuit, an overvoltage protection circuit and a DC/DC module circuit; the induction coil should be 4000 bundles and wound on the steel binding belt; the steel ribbon is made of a magnetic conductive material, the induction coil is converted into electric energy through induction electromagnetic energy, and energy storage and power supply are carried out through a capacitor in a circuit; the rectification filter circuit, the overvoltage protection circuit and the DC/DC module circuit are arranged in the protective shell.

9. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 2, wherein: the data processing of the data processing singlechip of the collector comprises early warning judgment and prediction algorithm processing.

10. The on-line temperature monitoring and early warning prediction system for the switch cabinet as claimed in claim 9, wherein:

the early warning judgment specifically refers to a single-point warning method and a multipoint differential method; the single-point alarm method comprises high-temperature alarm, temperature rise out-of-limit alarm and temperature rise overspeed alarm; the high-temperature alarm is that the temperature acquired by the digital temperature sensor exceeds 80 ℃, and the working current acquired by the current acquisition module is within the rated current, so that the alarm sends primary alarm information; the temperature rise out-of-limit alarm is that the temperature rise of a temperature measuring point exceeds 70K, and the working current is within the rated current, the alarm sends out secondary alarm information; the temperature rise overspeed alarm is that the real-time temperature rise rate of the temperature measuring points is greater than 1K/min, and the temperature rise rates of ten continuous temperature measuring points exceed the limit, and the alarm sends emergency defect information;

the multipoint differential method comprises in-cabinet in-phase transverse out-of-tolerance warning, in-cabinet out-of-phase transverse out-of-tolerance warning and similar cabinet type transverse out-of-tolerance warning, wherein the in-cabinet in-phase transverse out-of-tolerance warning is that if the temperature rise difference between different temperature measurement points of the same phase of the same switch cabinet at the same moment exceeds 5K, the alarm is used for giving corresponding warning according to different defect levels of general defects, major defects and emergent defects by combining the relative temperature difference of the different temperature measurement points as auxiliary judgment basis; the out-of-phase transverse out-of-difference alarm in the switch cabinet is that if the temperature rise between different temperature measuring points of different phases in the same switch cabinet at the same moment exceeds 5K, the alarm prompts corresponding alarms by combining the relative temperature difference of the different temperature measuring points as an auxiliary judgment basis, wherein the alarm prompts different levels of alarms, general defects, major defects and emergency defects; the similar cabinet type transverse out-of-tolerance alarm is carried out at the same time, the temperature rise between different temperature measuring points in the same station and the similar cabinets exceeds 5K, and the alarm is used for carrying out corresponding alarm by setting prompt alarm, general defects, major defects and emergency defects according to the relative temperature difference of the different temperature measuring points as auxiliary judgment basis;

the prediction algorithm is to use the temperature collected by the digital temperature sensor and the sampling current of the current collection module as input quantities, obtain a temperature rise prediction model by combining electrical knowledge, and obtain a theoretical temperature rise value of each temperature measurement point by using the temperature change trend as an output quantity.

Technical Field

The invention belongs to the technical field of power equipment, and particularly relates to an on-line temperature monitoring and early warning prediction system for a switch cabinet.

Background

The switch cabinet is a complete set of switch equipment, the internal structure of the switch cabinet comprises various protection devices such as a circuit breaker, an operating mechanism and a sensor, and the switch cabinet is mainly used for opening and closing and controlling and protecting electric equipment when an electric power system stably runs. Because the inside high-tension apparatus of cubical switchboard can produce resistive loss, hysteresis eddy current loss and dielectric loss and the structure of opening and shutting appears the oxidation wear, circuit breaker contact ageing and bus-bar joint are not hard up etc. all can make the inside temperature of cubical switchboard rise, the cubical switchboard leakproofness is strong and the air permeability is poor if the heat can not in time be discharged, too high temperature rise can make contact and cable crimping point overheat and burn out, serious accident such as power failure explosion even lead to the cubical switchboard to catch fire, the operation of the inside power equipment of cubical switchboard is unusual or the trouble shows for the rising of temperature usually, therefore the temperature on-line measuring and the early warning of cubical switchboard are to the most direct effectual means of power equipment control have important meaning to power system's reliability and security.

At present, various temperature measurement technologies mainly comprise contact temperature measurement and non-contact temperature measurement, and compared with the traditional method, namely a temperature indicating wax sheet method, the temperature measurement precision is simple and visual, and the temperature measurement precision is not high, and a person on duty needs to check the temperature measurement precision regularly, an optical fiber temperature measurement method is difficult to adapt to the problem that wiring is complex in a closed narrow environment in a switch cabinet, a creepage fault can be caused if dirt exists on the surface of an optical fiber after long-term working, and an infrared temperature measurement method is easy to be shielded by objects and has an installation problem. The current early warning system lacks the operation of further analyzing and processing temperature measurement data, mostly adopts single temperature threshold setting, is easy to cause misjudgment due to the generation of errors, and further lacks the operation of judging the possibility of future fault occurrence through the prediction of temperature rise trend.

Disclosure of Invention

The invention aims to provide an on-line temperature monitoring and early warning prediction system for a switch cabinet, aiming at the defects in the prior art. The invention can monitor the state and data of the power equipment in the switch cabinet in real time, can perform reliable early warning and prediction of future temperature rise trend to judge future faults, and can stably and permanently operate in the environment of high electromagnetic field and large current in the switch cabinet.

In order to achieve the purpose, the invention adopts the following technical scheme:

a temperature on-line monitoring and early warning prediction system for a switch cabinet comprises a temperature sending end, a collector and a display terminal; the temperature sending end is arranged in the switch cabinet and mainly comprises a wireless MCU, and a digital temperature sensor, a wireless transmitting antenna, an induction power taking module and a current acquisition module which are respectively connected with the wireless MCU; the temperature sending end carries out wireless data transmission with the collector through a wireless transmitting antenna; and the collector and the display terminal carry out data transmission through a GPRS communication network.

Further explaining, the collector comprises a data processing single chip microcomputer, and a wireless radio frequency receiving module, a memory, an alarm, a GPRS module and a display screen which are respectively connected with the data processing single chip microcomputer; the data processing single chip microcomputer is connected with the temperature sending end through the wireless radio frequency receiving module, receives temperature and current data transmitted by the temperature sending end and processes the data; the data processing single chip microcomputer transmits real-time data to the display terminal through the GPRS module; the memory is used for storing basic data information, including real-time temperature, historical temperature, current sampling data and basic information data; the alarm is used for carrying out temperature rise early warning and distinguishing different defect alarms and temperature rise prediction future fault alarms; the display screen is used for displaying basic data information and alarm information.

Further, the display terminal is an Ipad or a mobile phone or a computer.

Further, the digital temperature sensor adopts a DS18B20 patch; the current acquisition module adopts Rogowski coil for sampling and is magnetically saturated without an iron core; the induction electricity taking module is independent of the current collecting module, adopts an induction coil to take electricity, directly induces electromagnetic energy to obtain electric energy, and supplies power to the wireless MCU through filtering, rectifying and voltage stabilizing circuit; the wireless MCU is an ultra-low power consumption singlechip; the wireless transmitting antenna is a PCB antenna, and the anti-interference capability is enhanced by adopting copper-clad grounding treatment.

Further, the temperature transmitting end further comprises a protective shell; the wireless MCU, the digital temperature sensor, the wireless transmitting antenna and the current acquisition module are respectively and fixedly arranged in the protective shell; the protective shell is provided with a groove for placing the boron nitride heat-conducting block, and the digital temperature sensor is tightly attached to the boron nitride heat-conducting block.

Further, the protective shell is provided with a through hole for the binding band. The temperature sending terminal be equipped with a plurality of, through steel ribbon fixed mounting respectively at the inside plum blossom contact of cubical switchboard, female arranging and cable joint department to set up different ID in order to distinguish different positions, be convenient for follow-up data processing singlechip's data processing and analysis.

Further, the induction power taking module comprises an induction coil, a rectification filter circuit, an overvoltage protection circuit and a DC/DC module circuit; the induction coil should be 4000 bundles and wound on the steel binding belt; the steel ribbon is made of a magnetic conductive material, the induction coil is converted into electric energy through induction electromagnetic energy, and energy storage and power supply are carried out through a capacitor in a circuit; the rectification filter circuit, the overvoltage protection circuit and the DC/DC module circuit are arranged in the protective shell.

Further, the protective shell is made of epoxy resin materials, and can effectively insulate and resist high temperature to protect internal parts and circuits.

Further, the data processing of the data processing singlechip of the collector comprises early warning judgment and prediction algorithm processing.

Further, the early warning judgment specifically refers to a single-point warning method and a multipoint differential method; the single-point alarm method comprises high-temperature alarm, temperature rise out-of-limit alarm and temperature rise overspeed alarm; the high-temperature alarm is that the temperature acquired by the digital temperature sensor exceeds 80 ℃, and the working current acquired by the current acquisition module is within the rated current, so that the alarm sends primary alarm information; the temperature rise out-of-limit alarm is that the temperature rise of a temperature measuring point exceeds 70K, and the working current is within the rated current, the alarm sends out secondary alarm information; the temperature rise overspeed alarm is that the real-time temperature rise rate of the temperature measuring points is greater than 1K/min, and the temperature rise rates of ten continuous temperature measuring points exceed the limit, and the alarm sends emergency defect information; the multipoint differential method comprises in-cabinet in-phase transverse out-of-tolerance warning, in-cabinet out-of-phase transverse out-of-tolerance warning and similar cabinet type transverse out-of-tolerance warning, wherein the in-cabinet in-phase transverse out-of-tolerance warning is that if the temperature rise difference between different temperature measurement points of the same phase of the same switch cabinet at the same moment exceeds 5K, the alarm is used for giving corresponding warning according to different defect levels of general defects, major defects and emergent defects by combining the relative temperature difference of the different temperature measurement points as auxiliary judgment basis; the out-of-phase transverse out-of-difference alarm in the switch cabinet is that if the temperature rise between different temperature measuring points of different phases in the same switch cabinet at the same moment exceeds 5K, the alarm prompts corresponding alarms by combining the relative temperature difference of the different temperature measuring points as an auxiliary judgment basis, wherein the alarm prompts different levels of alarms, general defects, major defects and emergency defects; the similar cabinet type transverse out-of-tolerance alarm is carried out at the same time, the temperature rise between different temperature measuring points in the same station and the similar cabinets exceeds 5K, and the alarm is used for carrying out corresponding alarm by setting prompt alarm, general defects, major defects and emergency defects according to the relative temperature difference of the different temperature measuring points as auxiliary judgment basis; the prediction algorithm is to use the temperature collected by the digital temperature sensor and the sampling current of the current collection module as input quantities, obtain a temperature rise prediction model by combining electrical knowledge, and obtain a theoretical temperature rise value of each temperature measurement point by using the temperature change trend as an output quantity.

The working process of the temperature on-line monitoring and early warning prediction system for the switch cabinet comprises the following steps:

the protective shell of the temperature sending end is made of epoxy resin materials, binding band through holes penetrating through the protective shell through a steel binding band are respectively fixed at a plum blossom contact, a busbar and a cable joint for temperature and current sampling, IDs are set at different positions according to temperature measurement, a digital temperature sensor adopts a DS18B20 paster, the temperature measurement is realized in a contact mode through a heat conduction block in a groove of the protective shell in a direct contact mode, the transmission of temperature data can be realized only through a single bus, a current acquisition module adopts a Rogowski coil for current sampling, no magnetic saturation exists, an induction coil of an induction electricity taking module obtains electric energy by utilizing the electromagnetic induction principle independently of the Rogowski coil, stable direct current power supply is carried out through rectification, filtering and voltage stabilization, the electric energy obtained by the induction coil is stored through a capacitor, when the stored energy voltage exceeds 3.8V, the wireless MCU starts to sample current signals, and, when the voltage detection circuit detects that the voltage drops to about 2.8V which is the lowest voltage of the wireless MCU, the induction coil of the induction electricity taking module continuously stores energy and supplies power to the wireless MCU to 3.8V, the sampled data is converted into a digital signal which can be identified by a singlechip through an AD conversion circuit of the wireless MCU and is sent to a collector through a wireless transmitting antenna, the collector receives data through a wireless radio frequency receiving module, the data processing singlechip carries out temperature rise early warning judgment according to the received current and temperature data, the temperature rise early warning judgment is carried out through single-point warning method and multi-point differential method algorithm processing, the error caused by setting a single temperature threshold is avoided, different defect grade warning is carried out through an alarm, and warning position ID and temperature current data are displayed on a display screen, and finally, temperature rise trend prediction is carried out through a temperature rise prediction model obtained by the measured current and temperature data, the possibility of future fault occurrence is judged, the protection capability is further improved, and meanwhile, the temperature current data information and the early warning prediction information stored in the database are sent to a display terminal through a GPRS (general packet radio service) module, so that a worker can conveniently carry out real-time monitoring and timely find out and remove faults.

In the invention, the temperature sending end synchronously samples current and temperature and transmits data to the collector by a wireless MCU through a wireless radio frequency technology, a data processing singlechip of the collector carries out temperature rise early warning judgment through a temperature rise early warning comprehensive judgment algorithm according to the received temperature and current data, and alarm is carried out on unequal defect grades through an alarm, finally, a built temperature rise prediction model is adopted to predict the temperature rise trend, the data is sent to the display terminal in time for the real-time monitoring of the working personnel, the temperature on-line monitoring and early warning prediction system of the whole switch cabinet has simple structure, small volume and strong anti-interference capability, realizes the real-time monitoring of the temperature, utilizes the temperature rise early warning comprehensive judgment algorithm and the temperature rise prediction model to early process the early detection, and the future temperature rise trend is predicted to judge the possibility of future fault occurrence, so that the protection capability is further improved.

The invention has the advantages that:

1. the method is synchronous sampling when temperature and current sampling is carried out, namely the temperature and the current are collected at the same time, so that the influence on the accuracy of a temperature rise prediction algorithm model caused by errors caused by data asynchronization is reduced.

2. The induction coil of the induction electricity taking module and the Rogowski coil of the current acquisition module are completely independent, interference can be avoided, sampling precision is guaranteed, products are diversified, the Rogowski coil can be replaced at any time when current sampling is carried out on different products, the Rogowski coil is not limited by the induction coil, the current sampling uses the Rogowski coil to have no iron core, and the precision is high and has no magnetic saturation.

3. The heat conducting block between the digital temperature sensor and the temperature measuring point is made of boron nitride material, so that the heat conducting performance is good, the insulation is realized, and the requirement of contact temperature measurement of the temperature sensor is met.

4. The digital temperature sensor adopts a DS18B20 digital temperature sensor patch, a single bus can carry out data transmission, digital quantity can be directly output to be directly read by a single chip microcomputer, the size of the measuring module is greatly reduced, the power consumption is reduced, and the anti-interference capability is enhanced.

5. The wireless transmitting antenna adopts a PCB antenna, the hardware volume and the development cost are reduced, the use is more convenient, devices are placed in the vicinity of the wireless transmitting antenna as few as possible, the blank position is grounded by covering copper, the anti-interference capability is enhanced, and the wireless performance is optimized through a balun circuit consisting of a capacitor and an inductor, so that the radio frequency communication precision is high and the sensitivity is excellent.

6. The switch cabinet state is determined by adopting a temperature early warning comprehensive judgment method, the temperature rise defect grade is determined by comparing the temperature rise difference of different temperature measuring points between different phases and between similar cabinets by combining a single-point measurement alarm and a multipoint differential method, the misjudgment caused by the fact that the set temperature threshold value cannot be reached in time in the small current fault state during the judgment of a single temperature rise threshold value is avoided, the early warning of early temperature fault of the switch cabinet is realized by using the temperature early warning comprehensive judgment method, and the damage of a fault zone is reduced to the minimum.

7. The junction temperature change trend of the switch cabinet is influenced by the working current in the working process, and the junction temperature change always lags behind the current change, so that the possibility of future fault occurrence is judged by the temperature trend prediction during the establishment of the temperature rise prediction model, the equipment fault is prevented from being further expanded, and the protection capability is improved.

Drawings

Fig. 1 is a schematic diagram of a framework of an on-line temperature monitoring and early warning prediction system for a switch cabinet according to the present invention.

Fig. 2 is a schematic diagram of the installation of the temperature transmitting end and the tulip contact of the switch cabinet.

Fig. 3 is a schematic diagram of a temperature transmitter according to the present invention.

Fig. 4 is a sectional view showing a structure of a temperature transmitting terminal according to the present invention.

Reference numerals: 1-temperature sending end, 2-steel ribbon and 3-groove.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

Example (b):

as shown in fig. 1, an on-line temperature monitoring and early warning prediction system for a switch cabinet includes a temperature sending terminal, a collector, and a display terminal.

The temperature sending terminal be equipped with a plurality of, through steel ribbon fixed mounting respectively at the inside plum blossom contact of cubical switchboard, female arranging and cable joint department to set up different ID in order to distinguish different positions, be convenient for follow-up data processing singlechip's data processing and analysis. The temperature sending end mainly comprises a protective shell, a wireless MCU, a digital temperature sensor, a wireless transmitting antenna, an induction electricity taking module and a current acquisition module, wherein the digital temperature sensor, the wireless transmitting antenna, the induction electricity taking module and the current acquisition module are respectively connected with the wireless MCU; the wireless MCU, the digital temperature sensor, the wireless transmitting antenna and the current acquisition module are respectively and fixedly arranged in the protective shell; the protective shell is provided with a groove for placing the boron nitride heat-conducting block, and the digital temperature sensor is tightly attached to the boron nitride heat-conducting block. The protective casing is provided with a bandage through hole. See fig. 2, 3.

The digital temperature sensor adopts a DS18B20 patch; the current acquisition module adopts Rogowski coil for sampling and is magnetically saturated without an iron core; the induction electricity taking module is independent of the current collecting module, adopts an induction coil to take electricity, directly induces electromagnetic energy to obtain electric energy, and supplies power to the wireless MCU through filtering, rectifying and voltage stabilizing circuit; the wireless MCU is an ultra-low power consumption singlechip; the wireless transmitting antenna is a PCB antenna, and the anti-interference capability is enhanced by adopting copper-clad grounding treatment. The induction electricity taking module comprises an induction coil, a rectification filter circuit, an overvoltage protection circuit and a DC/DC module circuit; the induction coil should be 4000 bundles and wound on the steel binding belt; the steel ribbon is made of a magnetic conductive material, the induction coil is converted into electric energy through induction electromagnetic energy, and energy storage and power supply are carried out through a capacitor in a circuit; the rectification filter circuit, the overvoltage protection circuit and the DC/DC module circuit are arranged in the protective shell. The protective shell is made of epoxy resin materials, and can effectively insulate and resist high temperature to protect internal parts and circuits.

The collector comprises a data processing singlechip, and a wireless radio frequency receiving module, a memory, an alarm, a GPRS module and a display screen which are respectively connected with the data processing singlechip; the data processing single chip microcomputer is connected with the temperature sending end through the wireless radio frequency receiving module, receives temperature and current data transmitted by the temperature sending end and processes the data; the data processing single chip microcomputer transmits real-time data to the display terminal through the GPRS module; the memory is used for storing basic data information, including real-time temperature, historical temperature, current sampling data and basic information data; the alarm is used for carrying out temperature rise early warning and distinguishing different defect alarms and temperature rise prediction future fault alarms; the display screen is used for displaying basic data information and alarm information.

The data processing of the data processing singlechip of the collector comprises early warning judgment and prediction algorithm processing. The early warning judgment specifically refers to a single-point warning method and a multipoint differential method; the single-point alarm method comprises high-temperature alarm, temperature rise out-of-limit alarm and temperature rise overspeed alarm; the high-temperature alarm is that the temperature acquired by the digital temperature sensor exceeds 80 ℃, and the working current acquired by the current acquisition module is within the rated current, so that the alarm sends primary alarm information; the temperature rise out-of-limit alarm is that the temperature rise of a temperature measuring point exceeds 70K, and the working current is within the rated current, the alarm sends out secondary alarm information; the temperature rise overspeed alarm is that the real-time temperature rise rate of the temperature measuring points is greater than 1K/min, and the temperature rise rates of ten continuous temperature measuring points exceed the limit, and the alarm sends emergency defect information; the multipoint differential method comprises in-cabinet in-phase transverse out-of-tolerance warning, in-cabinet out-of-phase transverse out-of-tolerance warning and similar cabinet type transverse out-of-tolerance warning, wherein the in-cabinet in-phase transverse out-of-tolerance warning is that if the temperature rise difference between different temperature measurement points of the same phase of the same switch cabinet at the same moment exceeds 5K, the alarm is used for giving corresponding warning according to different defect levels of general defects, major defects and emergent defects by combining the relative temperature difference of the different temperature measurement points as auxiliary judgment basis; the out-of-phase transverse out-of-difference alarm in the switch cabinet is that if the temperature rise between different temperature measuring points of different phases in the same switch cabinet at the same moment exceeds 5K, the alarm prompts corresponding alarms by combining the relative temperature difference of the different temperature measuring points as an auxiliary judgment basis, wherein the alarm prompts different levels of alarms, general defects, major defects and emergency defects; the similar cabinet type transverse out-of-tolerance alarm is carried out at the same time, the temperature rise between different temperature measuring points in the same station and the similar cabinets exceeds 5K, and the alarm is used for carrying out corresponding alarm by setting prompt alarm, general defects, major defects and emergency defects according to the relative temperature difference of the different temperature measuring points as auxiliary judgment basis; the prediction algorithm is to use the temperature collected by the digital temperature sensor and the sampling current of the current collection module as input quantities, obtain a temperature rise prediction model by combining electrical knowledge, and obtain a theoretical temperature rise value of each temperature measurement point by using the temperature change trend as an output quantity.

The display terminal is an Ipad or a mobile phone or a computer.

The temperature sending end carries out wireless data transmission with the collector through a wireless transmitting antenna; and the collector and the display terminal carry out data transmission through a GPRS communication network.

The working principle of the above embodiment is as follows:

the protective shell of the temperature sending end is made of epoxy resin materials, binding band through holes penetrating through the protective shell through a steel binding band are respectively fixed at a plum blossom contact, a busbar and a cable joint for temperature and current sampling, IDs are set at different positions according to temperature measurement, a digital temperature sensor adopts a DS18B20 paster, the temperature measurement is realized in a contact mode through a heat conduction block in a groove of the protective shell in a direct contact mode, the transmission of temperature data can be realized only through a single bus, a current acquisition module adopts a Rogowski coil for current sampling, no magnetic saturation exists, an induction coil of an induction electricity taking module obtains electric energy by utilizing the electromagnetic induction principle independently of the Rogowski coil, stable direct current power supply is carried out through rectification, filtering and voltage stabilization, the electric energy obtained by the induction coil is stored through a capacitor, when the stored energy voltage exceeds 3.8V, the wireless MCU starts to sample current signals, and, when the voltage detection circuit detects that the voltage drops to about 2.8V which is the lowest voltage of the wireless MCU, the induction coil of the induction electricity taking module continuously stores energy and supplies power to the wireless MCU to 3.8V, the sampled data is converted into a digital signal which can be identified by a singlechip through an AD conversion circuit of the wireless MCU and is sent to a collector through a wireless transmitting antenna, the collector receives data through a wireless radio frequency receiving module, the data processing singlechip carries out temperature rise early warning judgment according to the received current and temperature data, the temperature rise early warning judgment is carried out through single-point warning method and multi-point differential method algorithm processing, the error caused by setting a single temperature threshold is avoided, different defect grade warning is carried out through an alarm, and warning position ID and temperature current data are displayed on a display screen, and finally, temperature rise trend prediction is carried out through a temperature rise prediction model obtained by the measured current and temperature data, the possibility of future fault occurrence is judged, the protection capability is further improved, and meanwhile, the temperature current data information and the early warning prediction information stored in the database are sent to a display terminal through a GPRS (general packet radio service) module, so that a worker can conveniently carry out real-time monitoring and timely find out and remove faults.

It should be understood that the above-described embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the practice of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description; this is not necessary, nor exhaustive, of all embodiments; and obvious variations or modifications of the invention may be made without departing from the scope of the invention.