CN107727968A - A kind of dry-type transformer condition monitoring device - Google Patents

Abstract

The invention discloses a kind of dry-type transformer condition monitoring device, including single-chip microcomputer, temperature-control circuit, 433M wireless receiving modules, GPRS wireless communication modules, Temperature Humidity Sensor, three current temperature combined type transes, the current temperature combined type trans is arranged on the low-voltage busbar output end of dry-type transformer, and current temperature combined type trans and the three-phase of the low-voltage busbar output end are corresponded and set；Current temperature combined type trans connects single-chip microcomputer by 433M wireless receiving modules, and temperature-control circuit, Temperature Humidity Sensor, GPRS wireless communication modules are connected with single-chip microcomputer.The present invention has expanded traditional detection range, has accomplished the combined state of real-time online detection transformer, simplifies the installation process of dry-type transformer condition monitoring device, solves the problems, such as the transformer telecommunication of distribution in length and breadth of land territorial scope.

Description

A dry-type transformer condition monitoring equipment

technical field

The invention relates to a power transformer monitoring, in particular to a dry-type transformer state monitoring equipment.

Background technique

At present, the thermal balance performance of dry-type transformers is poor. The traditional temperature controller of dry-type transformers detects the operating temperature of the transformer windings, drives the fan to realize forced air cooling and alarm control. The dry-type transformer temperature controller is mainly used to protect the dry-type transformer and prevent the transformer from being damaged due to excessive winding temperature. In addition, it also has a comprehensive temperature measurement and display function, which can display the temperature of the three-phase winding, the maximum temperature, the set temperature and the temperature set by the user; it can indicate over-temperature, over-temperature, fault status, and the settings can be changed through the keyboard temperature etc. The dry-type transformer temperature controller is an important part of maintaining the operation of the dry-type transformer. It can effectively prevent accidents caused by excessive temperature rise of the transformer, and can also promote the scientific management of the substation.

Traditional transformer thermostats generally use RS485 (or RS232, or 4-20mA) interface communication. With the continuous expansion of the application field of new dry-type transformers, higher requirements are put forward for the centralized monitoring of the dry-type transformers' operating status: the installed dry-type transformers have various distribution types, large differences in distance between each other, and unmanned transformers. Issues such as on-duty and multiple monitoring systems. If the temperature control system still uses wired communication, it is difficult to meet the requirements in many cases. With the development of computer technology and network technology, the development of networking, intelligence, integration and standardization of communication has put forward new requirements for traditional thermostats: the communication structure of the system should be as diverse as possible and use standard protocols. Communication methods, local wireless communication, long-distance wireless communication, network cloud management, etc. are the future development trends. Traditional dry-type transformer temperature controllers generally have three or four wired platinum resistance temperature sensors, and compare the monitored temperature data with the threshold value to generate control signals such as fan start and stop, over-temperature alarm, and over-temperature trip. The temperature data and control signals are directly displayed on-site through the instrument panel, and can also be transmitted to the remote monitoring center through wired communication cables.

However, the existing dry-type transformer temperature controller has the following defects:

It has the limitation of single monitoring, and the temperature data is only a state physical quantity, so it is difficult to accurately judge the load and fault conditions of the transformer only by temperature.

Contents of the invention

In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a dry-type transformer condition monitoring device, which can overcome the single defect of monitoring in the prior art.

The purpose of the present invention adopts following technical scheme to realize:

A dry-type transformer state monitoring device, which is applied to dry-type transformers, includes a single-chip microcomputer, a temperature control circuit, a 433M wireless receiving module, a GPRS wireless communication module, a temperature and humidity sensor, and three current and temperature composite sensors. The sensor is installed at the output end of the low-voltage busbar of the dry-type transformer, and the current-temperature composite sensor is set in one-to-one correspondence with the three-phase output end of the low-voltage busbar; the current-temperature composite sensor is connected to the single-chip microcomputer through the 433M wireless receiving module, and the temperature control circuit , temperature and humidity sensor, and GPRS wireless communication module are all connected with the single-chip microcomputer.

Further, the temperature control circuit includes at least three platinum resistance temperature sensors, an ESD protection circuit, a signal conditioning circuit, a multi-way switch and an analog-to-digital converter, and the three platinum resistance temperature sensors are all connected to the ESD protection circuit, and the ESD protection circuit, signal The conditioning circuit, the multi-way switch, the analog-to-digital converter and the single-chip microcomputer are connected in sequence.

Further, it also includes an RS485 communication module and/or a 4-20mA communication module, both of which are connected to the single-chip microcomputer.

Further, the single-chip microcomputer is also connected with a memory.

Further, the single-chip microcomputer is also connected with an operation keyboard.

Further, the single-chip microcomputer is also connected with a display screen.

Further, the single-chip microcomputer is also connected with an indicator light.

Further, the single-chip microcomputer is also connected with multiple relays.

Compared with the prior art, the beneficial effects of the present invention are:

(1) The present invention adds a dry-type transformer low-voltage three-phase output current monitoring function, expands the traditional detection range, and achieves real-time online detection of the composite state of the transformer. The monitored current data can be used for energy efficiency analysis and analysis of dry-type transformers. failure analysis;

(2) The temperature monitoring function of busbar contacts is added, and the communication mode of wireless transmission is adopted, which simplifies the installation process of dry-type transformer condition monitoring equipment, and avoids safety problems such as phase-to-phase short circuit caused by wired connection;

(3) The GPRS remote wireless communication module is added to solve the problem of remote communication of transformers distributed in a vast geographical range. All monitoring data are uploaded to the remote cloud server, and through the Internet, the operation of all transformers can be monitored online in real time around the world. state.

Description of drawings

Fig. 1 is a block diagram of an inventive dry-type transformer condition monitoring device.

detailed description

Below, the present invention will be further described in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of not conflicting, the various embodiments described below or the technical features can be combined arbitrarily to form new embodiments. .

As shown in Figure 1, the present invention provides a dry-type transformer state monitoring device, which is applied to a dry-type transformer, mainly including a single-chip microcomputer, a temperature control circuit, a 433M wireless receiving module, a GPRS wireless communication module, a temperature and humidity sensor, three current Composite temperature sensor. The current and temperature composite sensor is connected to the single-chip microcomputer through the 433M wireless receiving module, and the temperature control circuit, temperature and humidity sensor, and GPRS wireless communication module are all connected to the single-chip microcomputer. The temperature control circuit is a traditional dry-type transformer temperature controller, which realizes at least three-phase temperature monitoring, and includes at least three platinum resistance temperature sensors, an ESD protection circuit, a signal conditioning circuit, a multi-way switch and an analog-to-digital converter. The three platinum resistance temperature sensors are all connected to the ESD protection circuit, and the ESD protection circuit, the signal conditioning circuit, the multi-way switch, the analog-to-digital converter and the single-chip microcomputer are connected in sequence. It is also possible to add one more road, that is, one more platinum resistance temperature sensor.

The current-temperature composite sensor is installed at the output end of the low-voltage busbar of the dry-type transformer, and the current-temperature composite sensor is set in one-to-one correspondence with the three phases of the output end of the low-voltage busbar, and one for each of the three phases A/B/C . Through the on-site wireless collection function of the 433M wireless receiving module, the dry-type transformer state monitoring equipment can collect the load current data of the transformer, and can also collect the temperature data of the three-phase busbar contacts.

The GPRS wireless communication module transmits the collected transformer temperature data, current data, environmental temperature and humidity data, the action status of various relays, fan status and other information to the remote background server through the wireless network of mobile communication. The GPRS wireless communication module is preferably but not limited to USR-GPRS232-7S3 industrial-grade embedded GPRS module. The current and temperature composite sensor is based on the remote communication function of the GPRS wireless communication module, and runs the transformer status monitoring system cloud platform on the background server. Through the Internet, equipment managers can monitor the operation status of all networked transformers online in real time around the world.

The temperature and humidity sensor adopts the digital temperature and humidity sensor chip HTU21D. The temperature and humidity sensor is connected to the microcontroller through the I2C data line. It is used to monitor the temperature and humidity state information of the working environment where the dry-type transformer is located.

The present invention may further include an RS485 communication module and/or a 4-20mA communication module, both of which are connected to the single-chip microcomputer.

The single-chip microcomputer can also be connected with a memory, such as EEPROM, which is an erasable programmable read-only memory with electricity. In addition, the present invention may also include an operation keyboard for user input, a display screen for displaying the state information of the dry-type transformer, and an indicator light as an alarm warning, and the operation keyboard, display screen, and indicator light are all connected to the single-chip microcomputer.

It also includes multi-channel relays connected to the single-chip microcomputer. The multi-channel relays generally include over-temperature alarm output, over-temperature trip output, working status output, iron core alarm output, fan alarm output, power failure alarm output, fan control output, etc. Of course, in the practical application of the present invention, a power supply module needs to be configured to provide electric energy for the entire device.

The above-mentioned embodiment is only a preferred embodiment of the present invention, and cannot be used to limit the protection scope of the present invention. Any insubstantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of the present invention. Scope of protection claimed.

Claims (8)

1. A dry-type transformer state monitoring device, which is applied to a dry-type transformer, is characterized in that it includes a single-chip microcomputer, a temperature control circuit, a 433M wireless receiving module, a GPRS wireless communication module, a temperature and humidity sensor, and three current and temperature composite sensors, The current-temperature composite sensor is installed on the output end of the low-voltage busbar of the dry-type transformer, and the current-temperature composite sensor is set in one-to-one correspondence with the three phases of the low-voltage busbar output end; the current-temperature composite sensor passes through the 433M wireless receiving module Connect the single-chip microcomputer, the temperature control circuit, the temperature and humidity sensor, the GPRS wireless communication module are all connected with the single-chip microcomputer. 2. The dry-type transformer condition monitoring device as claimed in claim 1, wherein the temperature control circuit comprises at least three platinum resistance temperature sensors, an ESD protection circuit, a signal conditioning circuit, a multi-way switch and an analog-to-digital converter, three Each of the platinum resistance temperature sensors is connected to the ESD protection circuit, and the ESD protection circuit, the signal conditioning circuit, the multi-way switch, the analog-to-digital converter and the single-chip microcomputer are connected in sequence. 3. The dry-type transformer condition monitoring device according to claim 1, further comprising an RS485 communication module and/or a 4-20mA communication module, both of which are connected to the single-chip microcomputer. 4. The dry-type transformer condition monitoring device according to claim 1, characterized in that the single-chip microcomputer is also connected with a memory. 5. The dry-type transformer condition monitoring device according to claim 1, characterized in that the single-chip microcomputer is also connected with an operation keyboard. 6. The dry-type transformer condition monitoring device according to claim 1, wherein the single-chip microcomputer is also connected with a display screen. 7. The dry-type transformer condition monitoring device according to claim 1, characterized in that the single-chip microcomputer is also connected with an indicator light. 8. The dry-type transformer condition monitoring device according to claim 1, wherein the single-chip microcomputer is also connected with multiple relays.