CN201413196Y - Wireless monitoring system for electric overhead cable contact temperature - Google Patents

Abstract

The utility model discloses a wireless monitoring system for the contact temperature of electric overhead cables. It is a temperature acquisition device with a wireless temperature measurement device as the main body, which can monitor the real-time data of the scene at the remote end, which greatly improves the safe operation of the power grid. Its structure is: it adopts a layered distributed structure, which is composed of an acquisition layer, a collection layer and a monitoring layer; the acquisition layer includes several wireless temperature measurement devices, and each wireless temperature measurement device is connected to the measured object; Receiving management terminal; the monitoring layer is a number of local monitoring computers and at least one dispatching terminal monitoring computer and database; the wireless receiving management terminal processes the collected temperature data sent by each corresponding wireless temperature measuring device, and after processing, passes through mobile communication GPRS The data is transmitted to the communication manager, and the communication manager transmits it to the corresponding local monitoring computer and the monitoring computer at the dispatching end. The local monitoring computer and the monitoring computer at the dispatching end manage the data and send out corresponding alarm signals.

Description

Wireless monitoring system for electric overhead cable contact temperature

technical field

The utility model relates to a wireless monitoring system for the contact temperature of electric overhead cables.

Background technique

With the rapid development of the economy, the demand for electricity is also increasing. Now people's life is inseparable from the demand for electricity every moment. Every power failure seriously interferes with people's normal life and work, especially With the rapid development of science and technology, the popularization and application of electrical automation equipment in production and electrical equipment in life, it is particularly important to ensure safe power supply. At present, ensuring safe power supply is regarded as a permanent issue in various countries and regions around the world. Research and exploration, are also constantly introducing some new technologies applied to ensure power supply.

When the power grid is powered, the power primary equipment is mainly used to complete the power transmission to the loads of each voltage level, and the temperature is an important parameter to investigate the safe operation of the primary equipment, so it is urgent to monitor the temperature of the power primary equipment.

High-voltage power overhead cables are key equipment for power transmission. During the long-term operation of the power grid, the cable contacts will heat up due to aging or excessive contact resistance, and the temperature of these heat-generating parts cannot be monitored in real time, so it is very easy to cause accidents such as equipment burning or sudden power failure. By monitoring the operation of the contact temperature, it can effectively prevent the cable from burning out and ensure the stable operation of the power supply system. Power cables are mostly erected in remote areas, and at the same time, they are erected at a high height, which makes manual inspection and temperature measurement impossible, and the usual temperature measurement methods cannot be used.

There is a temperature monitoring system for switch cabinets in foreign countries. The laser temperature sensor is placed in the switch cabinet where it is easy to overheat to measure the temperature. The battery is preset in the sensor to provide power for the sensor; the temperature display is installed on the switch cabinet door. Used to display the temperature of the switch lead connector from the sensor; connect the laser temperature sensor and the temperature display with an optical fiber. The optical fiber is insulated, does not reduce the electrical distance, and meets the safety requirements, but there are still the following disadvantages:

(1) The performance is unreliable. Since the power supply of the sensor is provided by the battery, once the battery fails, the monitoring will be interrupted, and the replacement of the battery requires a power failure of the switch cabinet, which affects the reliability of the power supply.

(2) The operation is unstable, because the optical fiber connection is used between the sensor and the temperature display screen, and the cable is easily broken during maintenance.

(3) The installation workload is heavy, and the original switchgear needs to be modified.

There are also temperature measuring devices used for lead wire joints in switch cabinets in China. The principle is that when the temperature of the measured point is higher than the set temperature, the spring contact of the device is closed, and the signal circuit alarm is activated, but the accurate temperature cannot be quantitatively measured and cannot be recorded. Historical data cannot grasp the temperature change trend.

Utility model content

The purpose of this utility model is to solve the above problems and provide a wireless monitoring system for the contact temperature of electric power overhead cables. It uses a wireless temperature measuring device as the main temperature acquisition device, and can monitor the real-time data on the spot at the remote end. Improved safe operation of the grid.

In order to achieve the above object, the utility model adopts the following technical solutions:

A wireless temperature monitoring system for overhead cable contacts, which adopts a layered distributed structure and consists of an acquisition layer, a collection layer and a monitoring layer; the acquisition layer includes several wireless temperature measuring devices, and each wireless temperature measuring device is connected to the measured Object connection; the collection layer is a number of wireless receiving management terminals, each wireless receiving management terminal exchanges information with the communication manager through mobile communication GPRS; the monitoring layer is a number of local monitoring computers and at least one dispatching terminal monitoring computer and database; each wireless receiving The management terminal and each wireless temperature measuring device are connected by wireless communication; the wireless receiving management terminal processes the collected temperature data sent by each corresponding wireless temperature measuring device, and transmits the processed data to the communication management through mobile communication GPRS The communication manager transmits to the corresponding local monitoring computer and the dispatching end monitoring computer through RS485, and the local monitoring computer and the dispatching end monitoring computer manage the data and issue corresponding control commands.

Described wireless temperature measuring device comprises wireless transmitting and receiving module 1, A/D converter, logic interface 1, power management module 1, and temperature sensor is installed on the temperature measuring point, and temperature sensor is connected with A/D converter simultaneously; The receiving module 1 is connected to the antenna 1, the logic interface 1 is connected to the programmable memory 1, the clock chip, and the read-only memory, and the external power supply 1 is connected to the temperature sensor, the power management module 1, the read-only memory, the clock chip, and the programmable memory respectively. I connect.

The wireless receiving management terminal includes a wireless receiving and transmitting module II, and the wireless receiving and transmitting module II is connected to the antenna II; the logic interface II is connected to the programmable memory II, the serial communication interface, and the address switch respectively, and the external power supply II is connected to the power management Module II, serial communication interface and programmable memory II are connected.

The monitoring computer at the dispatching end is connected to the optical communication PCM equipment through an optical fiber, and the optical communication PCM equipment is connected to the communication manager; the communication manager is also connected to the local monitoring computer.

Both the external power supply I and the external power supply II use at least one of transformers, solar energy or batteries.

Both the wireless transmitting and receiving module I and the wireless receiving and transmitting module II are 433MHz or 355MHz wireless modules.

The serial communication interface includes a point-to-point transmission communication serial port and a differential transmission communication serial port.

The address switch is a digital switch.

The utility model adopts a layered distributed structure, which ensures the flexibility of the system configuration and the convenience of function configuration. The system as a whole is divided into three layers: acquisition layer, collection layer and monitoring layer.

The collection layer and the collection layer adopt the wireless communication mode, and the collection layer and the monitoring layer are connected by the communication network line.

The wireless temperature measuring device on the collection layer sends the temperature of the measured object collected by the temperature sensing element to the wireless receiving management terminal on the collecting layer through wireless communication, and the wireless receiving management terminal sends the collected data from each wireless temperature measuring device. The temperature data is processed and transmitted to the communication manager through mobile communication GPRS, and the communication manager transmits it to the local monitoring computers on the monitoring layer through the RS-485 port and data lines, and at the same time transmits it to the monitoring computer at the dispatching end through the fiber channel network Each monitoring computer manages the data through the application software of this system, records the time and value of the temperature crossing the line, and sends out an alarm signal.

The wireless receiving management terminal can manage up to 500 wireless temperature measuring devices. When the number of wireless temperature measuring devices exceeds 500, two wireless receiving management terminals need to be used. At this time, the two wireless receiving management terminals need to be connected remotely through a communication manager. The information of all wireless temperature measuring devices is sent to the computers on the monitoring layer.

The beneficial effects of the utility model:

1. It can monitor the temperature of electrical equipment, especially the connection point of high-voltage overhead cables in real time. When the operating temperature of the equipment exceeds the preset alarm temperature value, the system will automatically warn so that measures can be taken in time to ensure the safe and reliable operation of the power grid .

2. There is no error caused by manual temperature measurement in this system. The temperature-sensing element of the infinite temperature measurement device is closely attached to the surface of the measured contact, with high precision and strong reliability.

3. The system is simple in structure, easy to maintain and highly intelligent.

Description of drawings

Fig. 1 is the structural representation of the utility model;

Fig. 2 is a schematic structural diagram of a wireless temperature measuring device;

Fig. 3 is a schematic structural diagram of a wireless reception management terminal.

Among them, 1. Acquisition layer, 2. Collection layer, 3. Monitoring layer, 4. Wireless temperature measuring device, 401. Wireless transmitting and receiving module I, 402. A/D converter, 403. Power management module I, 404. Logic Interface 1, 405. antenna 1, 406. temperature sensor, 407. external power supply 1, 408. read-only memory, 409. clock chip, 410. programmable memory 1, 411. temperature measuring point, 5. wireless receiving management terminal, 501. Wireless receiving and transmitting module II, 502. Power management module II, 503. Logic interface II, 504. Antenna II, 505. External power supply II, 506. Address switch, 507. Point-to-point transmission communication serial port, 508. Differential transmission communication serial port , 509. Programmable memory II, 6. Communication manager, 7. Optical communication PCM equipment, 8. Local monitoring computer, 9. Dispatch terminal monitoring computer, 10. Database.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

In Fig. 1, the utility model adopts layered distributed structure, is made up of collection layer 1, collection layer 2 and monitoring layer 3; The objects are connected; the collection layer 2 is a plurality of wireless reception management terminals 5, and each wireless reception management terminal 5 is connected with the communication manager 6; the monitoring layer 3 is a plurality of local monitoring computers 8 and at least one dispatching end monitoring computer 9 and a database 10; each The wireless receiving management terminal 5 and each wireless temperature measuring device 4 are connected by wireless communication (frequency is 433MHz or 355MHz); the wireless receiving management terminal 5 performs data processing on the collected temperature data sent by each corresponding wireless temperature measuring device 4 , passed to the communication manager 6 through the mobile communication GPRS mode, passed to the corresponding local monitoring computer 8 and the dispatching end monitoring computer 9 through the communication manager 6, the local monitoring computer 8 and the dispatching end monitoring computer 9 manage the data, and send corresponding control command. The monitoring computer 9 at the dispatching end is connected to the optical communication PCM device 7 through an optical fiber, and the optical communication PCM device 7 is connected to the communication manager 6; the communication manager 6 is also connected to the local monitoring computer 8 at the same time.

Among Fig. 2, wireless temperature measuring device 4 comprises wireless transmitting and receiving module 1401, A/D converter 402, logic interface 1404, power supply management module 1403, and temperature sensor 406 is installed on the temperature measuring point 411, and temperature sensor 406 is connected with A/D simultaneously. The D converter 402 is connected; the wireless transmitting and receiving module I401 is connected with the antenna I405, the logic interface I404 is respectively connected with the programmable memory I410, the clock chip 409, and the read-only memory 408, and the external power supply I407 is respectively connected with the temperature sensor 406 and the power management module I403 , ROM 408, clock chip 409, and programmable memory I404 are connected.

In Fig. 3, wireless receiving management terminal 5 comprises wireless receiving and transmitting module II501, and wireless receiving and transmitting module II501 is connected with antenna II504; Logical interface II503 is connected with programmable memory II509, serial communication interface, address switch 506 respectively, external power supply II505 It is connected with power management module II502, serial communication interface and programmable memory II509. The serial communication interface includes a point-to-point transmission communication serial port 507 and a differential transmission communication serial port 508 . Address switch 506 is a digital switch.

The external power supply I407 and the external power supply II505 can be a joint power supply mode of transformer/solar energy and battery, and the transformer/solar energy supplies power to the system while charging the battery; or it can supply power to the transformer.

Both the wireless transmitting and receiving module I401 and the wireless receiving and transmitting module II501 are 433MHz wireless modules.

Programmable memory I404 and programmable memory II509 use 25AA1024 chip; clock chip 409 uses DS1302; read-only memory 408 uses AT24C256 chip; antenna I405 and antenna II504 use single-ended 50-ohm antenna; temperature sensor uses PT1000.

Through the application of the above technologies, the entire acquisition terminal solves technical problems such as temperature acquisition, temperature data processing, and wireless transmission of temperature data, and realizes real-time temperature monitoring of key parts of power primary equipment.

Compared with the prior art, the utility model:

(1) The existing high-voltage contact temperature detection generally adopts the method of infrared indirect measurement (such as some imported handheld thermometers). The accuracy is easily affected by the environment of the measurement point and the surface state, and the error between the measured value and the actual value is relatively large. And it can only measure the place that can be seen directly, and manual operation is required. The temperature monitoring system adopts the method of direct measurement, which has high accuracy and is not affected by environmental factors. The temperature sensor uses a national standard temperature sensor, which has high stability and good interchangeability. ), with good consistency and other characteristics. The temperature measurement point of the detector can be selected arbitrarily, without being limited by whether it can "see directly", it is more suitable for a new type of closed switchgear, and it does not require manual operation, and it can achieve online automatic measurement.

(2) Data transmission adopts a wireless method, which not only solves the problem of high-voltage isolation but also ensures that the data is not distorted and is not affected by strong electric and magnetic fields. The remote transmission of on-site data adopts the mobile communication GPRS method, which is not affected by the environment and does not need to set up communication optical cables.

(3) In order to ensure high-voltage isolation, the working power of the detector working at the high-voltage end is obtained by the main circuit working current induction method. Due to the use of a unique power supply circuit, the main circuit working current can ensure that the detector normal work.

(4) The values of all temperature monitoring points are reflected in the monitoring software of the host computer in real time to realize real-time monitoring of temperature. At the same time, if the temperature is too high, the monitoring system can alarm in different ways, remind users to deal with hidden dangers in time, and eliminate faults in the bud, so as to ensure the safe and reliable operation of equipment and provide a strong guarantee for enterprise production.

Through the network operation of each workstation, it can form a network monitoring of the operation status of the power grid within a certain area to achieve:

(a) The operating temperature status of each contact in the monitoring area can be accurately monitored in real time.

(b) Comprehensively monitor the temperature status of the overhead line contacts of the power grid in the area, provide a reliable basis for the safe operation and scheduling of the power grid, and prevent accidents before they happen.

(c) Real-time monitoring of the temperature value of each monitoring point can save the overhead line and power grid operation data for a long time, and provide scientific basis for the analysis of the overall working status of the power grid and other management.

Performance characteristics:

The wireless temperature measuring device can realize a wide range of temperature (-20 ℃ ~ 300 ℃) collection

The wireless temperature measuring device is suitable for a rated current of 5-4000A.

The communication adopts wireless transmission and reception, which effectively improves the safety performance of the system. The communication distance is 80m, and the wireless temperature measurement device can meet the installation needs of each test point.

The response speed is fast, and the fault alarm time is less than 1s.

Complete event message processing, text and voice alarms, and data storage.

Friendly man-machine interface, Chinese character display, printing; capable of querying, deleting, and drawing curves for historical data.

The background communication mode is flexible, equipped with RS485 communication interface.

The wireless receiving management terminal can manage 500 wireless temperature measuring devices at the same time within the effective wireless receiving range.

Easy to install, less maintenance, simple and practical, easy to operate.

Wireless temperature measuring device

①The temperature measurement method is direct contact temperature measurement; the temperature sensing device of the wireless temperature measurement device is in direct and close contact with the device at the monitoring point

②The temperature data transmission method is wireless transmission; the temperature data of the wireless temperature measuring device is sent to the receiving device (wireless receiving management terminal) in a wireless way

③Wireless temperature measuring device Temperature measuring range -20～300℃;

Temperature sampling accuracy ±3°C

④The wireless temperature measuring device can be placed in any designated position, and it is installed firmly, and will not be loosened or damaged due to mechanical vibration or high temperature;

⑤ The installation method of the wireless temperature measuring device does not affect the normal maintenance work, and does not affect the safe insulation distance;

⑥The wireless temperature measuring device can work continuously for at least 5 years without maintenance.

⑦ The wireless transmission range of the wireless temperature measurement device is up to 80 meters; (the wireless temperature measurement device is placed in a closed metal high-voltage switch cabinet, and the communication distance is 20m, which can ensure the correct signal transmission)

⑧ The low-power devices used in the wireless transmission of the wireless temperature measuring device will not cause any impact on other wireless communication devices during the working process;

⑨ The temperature collection time interval of the wireless temperature measuring device is adjustable.

Claims (7)

1. A wireless monitoring system for the contact temperature of electric power overhead cables is characterized in that it adopts a layered distributed structure and is composed of an acquisition layer, a collection layer and a monitoring layer; wherein the acquisition layer includes several wireless temperature measuring devices, each wireless The temperature measuring device is connected with the measured object; the collection layer is several wireless receiving management terminals, and each wireless receiving management terminal is connected with the communication manager through mobile communication GPRS; the monitoring layer is several local monitoring computers and at least one dispatching terminal monitoring computer and Database; each wireless receiving management terminal and each wireless temperature measuring device are connected by wireless communication; the wireless receiving management terminal will process the collected temperature data sent by each corresponding wireless temperature measuring device, and after processing, use the mobile communication GPRS method The data is transmitted to the communication manager, and the communication manager transmits it to the corresponding local monitoring computer and the dispatching end monitoring computer through the computer network. The local monitoring computer and the dispatching end monitoring computer manage the data and send corresponding alarm information. 2. the power overhead cable contact temperature wireless monitoring system as claimed in claim 1, is characterized in that, described wireless temperature measuring device comprises wireless transmitting and receiving module 1, A/D converter, logic interface 1, power supply management module 1 , the temperature sensor is installed on the temperature measuring point, and the temperature sensor is connected with the A/D converter at the same time; the wireless transmitting and receiving module 1 is connected with the antenna 1, and the logic interface 1 is respectively connected with the programmable memory 1, the clock chip, and the read-only memory. The power supply 1 is connected to the temperature sensor, the power management module 1, the read-only memory, the clock chip, and the programmable memory 1 respectively. 3. The wireless monitoring system for overhead cable contact temperature as claimed in claim 1, wherein the wireless receiving management terminal includes a wireless receiving and transmitting module II, and the wireless receiving and transmitting module II is connected with the antenna II; the logic interface II then The external power supply II is connected to the power management module II, the serial communication interface and the programmable memory II respectively. 4. The electric overhead cable contact temperature wireless monitoring system as claimed in claim 1, characterized in that, the dispatching end monitoring computer optical fiber is connected with the optical communication PCM equipment, and the optical communication PCM equipment is connected with the communication manager; the communication manager At the same time, it is also connected with the local monitoring computer. 5. The wireless monitoring system for contact temperature of electric power overhead cables according to claim 2 or 3, characterized in that, both the external power supply I and the external power supply II are powered by transformers or batteries. 6. The wireless monitoring system for overhead cable contact temperature as claimed in claim 2 or 3, wherein the wireless transmitting and receiving module I and the wireless receiving and transmitting module II are both 433MHz or 355MHz wireless modules. 7. The wireless monitoring system for contact temperature of electric overhead cables according to claim 3, wherein the serial communication interface includes a point-to-point transmission communication serial port and a differential transmission communication serial port.

Images