CN104931770A - Internet of things technology-based transformer iron core grounding current detection method - Google Patents

Abstract

The invention discloses a transformer core grounding current detection method based on the Internet of Things technology. Several transformer core current sensors are correspondingly installed on flat steel grounding lines to be tested, and analog current signals on the corresponding grounding lines are respectively collected. The current signal detected by the transformer core current sensor is processed by the I/V conversion circuit, differential voltage amplification circuit and filter circuit in the transformer core ground current detection device based on Internet of Things technology. Send the signal to the AD acquisition unit of the core processing unit of the single-chip control circuit; perform FFT spectrum analysis and calculation. The single-chip microcomputer control circuit responds to the data calling and testing of the remote monitoring platform, and uploads the collected iron core current to the remote monitoring platform through the wireless communication unit. Compared with the prior art, the present invention has the following advantages: a transformer core grounding current detection method based on the Internet of Things technology of the present invention monitors on-line in real time, detects line problems in time, and ensures normal operation of the power grid.

Description

A transformer core ground current detection method based on Internet of Things technology

technical field

The invention relates to a method for detecting ground current of a transformer core, in particular to a method for detecting ground current of a transformer core based on Internet of Things technology.

Background technique

When the transformer core is in operation, the electric field and magnetic field of the coil make each part of the core have different potentials. If the core is not reliably grounded, intermittent discharges may occur due to different potentials and damage its insulation; another On the one hand, if the transformer core is grounded at multiple points, a closed loop is formed between every two grounding points through the core itself and the grounding loop, in which the interlinked magnetic flux will induce a circulating current in the loop, causing the core to overheat locally , In severe cases, it will cause local burning. When a multi-point ground fault occurs, the ground current does not necessarily exceed the 100mA specified in the regulations, so this small current ground fault is not easy to be detected early. At present, there are deficiencies in the regular detection by clamp meter, the detection of the insulation resistance of the transformer iron core to the ground, and the gas chromatography analysis method, and the fault cannot be found in time. Therefore, real-time online detection of the transformer core ground current is very necessary. The invention comprehensively applies the ZIGBEE wireless communication technology in the Internet of Things technology and the TCP/IP technology in the Internet to realize the real-time on-line detection of the transformer iron core grounding current.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a transformer core ground current detection method based on Internet of Things technology.

The present invention is achieved through the following technical solutions: a transformer core grounding current detection method based on Internet of Things technology, comprising the following steps:

(1) Several transformer core current sensors are correspondingly installed on the flat steel grounding wire to be tested, and the analog current signals on the corresponding grounding wire are respectively collected;

(2) The transformer core ground current detection device based on the Internet of Things technology is connected with the transformer core current sensor by communication. The transformer core ground current detection device based on the Internet of Things technology has a built-in single-chip control circuit, ZIGBEE communication module and wireless communication circuit. The ZIGBEE network is a network for several transformer core current sensors;

(3) The transformer core current sensor converts the detected current signal into a differential voltage output through the I/V conversion circuit in the transformer core grounding current detection device based on Internet of Things technology;

(4) amplifying the differential voltage signal output by step (3) through a differential voltage amplifier circuit;

(5) the voltage signal amplified in step (4) is filtered through a filter circuit;

(6) the signal after step (5) processing is sent to the AD acquisition unit of the core processing unit of the single-chip microcomputer control circuit;

(7) the core processing unit of single-chip microcomputer control circuit carries out FFT spectrum analysis to the signal that step (6) collects and calculates the iron core current size;

(8) The core processing unit of the single-chip microcomputer control circuit periodically stores the data collected;

(9) The core processing unit of the single-chip microcomputer control circuit responds to the data call of the remote monitoring platform, and uploads the collected iron core current to the remote monitoring platform through the wireless communication unit.

As a further optimization of the above scheme, the remote monitoring platform monitors the current data collected by the transformer iron core current sensor in real time, and for the alarm data, through wireless transmission, the remote monitoring platform sends the alarm information to the set in the database in the form of an alarm message. On the mobile phone of the designated responsible person.

As a further optimization of the above scheme, the transformer core grounding current detection device based on Internet of Things technology has a built-in single-chip control circuit, signal conditioning circuit, clock module, ZIGBEE communication module, data storage circuit, wireless communication module, serial communication interface circuit And for the power supply circuit of above-mentioned circuit power supply, described single-chip microcomputer control circuit is the embedded system that microprocessor chip and peripheral circuit thereof form, the signal output end of microprocessor chip and signal conditioning circuit, clock module, ZIGBEE communication module, data The data storage circuit, the wireless communication module, the serial port communication interface circuit, and the signal input end of the power supply circuit are electrically connected.

As a further optimization of the above solution, the microprocessor chip is a CORTEX-M3 processor.

As a further optimization of the above solution, the signal conditioning circuit includes an I/V conversion circuit, a differential amplifier circuit and a filter circuit, and the current signal collected by the transformer core current sensor passes through the I/V conversion circuit, the differential amplifier circuit and the filter circuit. After being processed by the filtering circuit, it is sent to the AD acquisition circuit of the single-chip microcomputer control circuit for processing and operation by the single-chip microcomputer control circuit.

As a further optimization of the above solution, the serial communication interface circuit is a MAX485 interface circuit, and the transformer core ground current detection device based on Internet of Things technology is electrically connected to the transformer core current sensor through the RS485 bus.

Compared with the prior art, the present invention has the following advantages: The present invention provides a transformer core grounding current detection method based on the Internet of Things technology, which adopts a split-type high-precision current sensor to collect data, and does not need to disconnect the transformer core when installing the current sensor. Core ground wire, easy to install; wide measurement range, up to 100A, resolution up to 0.001mA. The ZIGBEE network is used to network multiple transformer core current detection devices, and the wireless communication unit is used as the ZIGBEE central unit to process and transmit the measurement data of each terminal node to the remote monitoring center through the TCP\IP network. A transformer core grounding current detection device based on the Internet of Things technology of the present invention is connected to the existing monitoring platform for real-time monitoring of transformer core current data. For real-time alarm information, the monitoring platform sends the alarm information to the responsible person's mobile phone terminal superior. The method for detecting the ground current of a transformer iron core based on the Internet of Things technology of the present invention realizes real-time online monitoring, can detect problems in time, and ensures the normal operation of the power grid, and has good application prospects.

Description of drawings

Fig. 1 is a flow chart of transformer core ground current detection based on Internet of Things technology according to the present invention.

Fig. 2 is a block diagram of the circuit structure of a transformer core ground current detection device based on the Internet of Things technology of the present invention.

Fig. 3 is a schematic diagram of processing the collected current signal in the present invention.

FIG. 4 is a schematic circuit diagram of the I/V conversion circuit of the present invention.

Fig. 5 is a schematic circuit diagram of the differential amplifier circuit of the present invention.

Fig. 6 is a schematic circuit diagram of the filter circuit of the present invention.

Detailed ways

The embodiments of the present invention are described in detail below. This embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are provided, but the protection scope of the present invention is not limited to the following implementation example.

Referring to FIG. 1 , it is a flow chart of transformer core ground current detection based on Internet of Things technology of the present invention. A transformer core grounding current detection method based on Internet of Things technology, comprising the following steps:

(1) Several transformer core current sensors are correspondingly installed on the flat steel grounding wire to be tested, and the analog current signals on the corresponding grounding wire are respectively collected;

(2) The transformer core ground current detection device based on the Internet of Things technology is connected with the transformer core current sensor by communication. The transformer core ground current detection device based on the Internet of Things technology has a built-in single-chip control circuit, ZIGBEE communication module and wireless communication circuit. The ZIGBEE network is a network for several transformer core current sensors;

(3) The transformer core current sensor converts the detected current signal into a differential voltage output through the I/V conversion circuit in the transformer core grounding current detection device based on Internet of Things technology;

(4) amplifying the differential voltage signal output by step (3) through a differential voltage amplifier circuit;

(5) the voltage signal amplified in step (4) is filtered through a filter circuit;

(6) the signal after step (5) processing is sent to the AD acquisition unit of the core processing unit of the single-chip microcomputer control circuit;

(7) the core processing unit of single-chip microcomputer control circuit carries out FFT spectrum analysis to the signal that step (6) collects and calculates the iron core current size;

(8) The core processing unit of the single-chip microcomputer control circuit periodically stores the data collected;

(9) The core processing unit of the single-chip microcomputer control circuit responds to the data call of the remote monitoring platform, and uploads the collected iron core current to the remote monitoring platform through the wireless communication unit.

A transformer core grounding current detection device based on Internet of Things technology is communicatively connected with a transformer core current sensor. The transformer core current sensor is installed on a flat steel grounding wire for collecting analog current signals on the grounding wire. Referring to FIG. 2 , a block diagram of a circuit structure of a transformer core ground current detection device based on the Internet of Things technology according to the present invention. A transformer core grounding current detection device based on Internet of Things technology built-in single-chip control circuit, signal conditioning circuit, clock module, ZIGBEE communication module, data storage circuit, wireless communication module, serial communication interface circuit and power supply for the above circuits circuit, the single-chip control circuit is an embedded system composed of a microprocessor chip and its peripheral circuits, the signal output terminal of the microprocessor chip and the signal conditioning circuit, clock module, ZIGBEE communication module, data storage circuit, wireless communication module, serial port The signal input terminals of the communication interface circuit and the power supply circuit are electrically connected. Optimized, the microprocessor chip is a CORTEX-M3 processor.

The signal conditioning circuit includes I/V conversion circuit, differential amplifier circuit and filter circuit. Referring to FIG. 3 , it is a schematic diagram of processing the collected current signal of the present invention. The current signal collected by the transformer core current sensor is processed by the I/V conversion circuit, the differential amplifier circuit and the filter circuit, and then sent to the AD acquisition circuit of the single-chip microcomputer control circuit for processing and operation by the single-chip microcomputer control circuit.

A transformer core grounding current detection device based on the Internet of Things technology of the present invention, the serial port communication interface circuit is a MAX485 interface circuit, and the transformer core grounding current detection device based on the Internet of Things technology is electrically connected to the transformer core current sensor through the RS485 bus .

See Figure 4-Figure 6, Figure 4 is the circuit schematic diagram of the I/V conversion circuit, the I/V conversion circuit includes two transport amplifiers and six resistors, the analog signal AI output by the transformer core current sensor, I/V The conversion circuit conditions the analog signal AI into differential outputs +IN and -IN. FIG. 5 is a circuit schematic diagram of a differential amplifier circuit. The differential amplifier circuit includes two transport amplifiers and four resistors R, the differential amplifier circuit amplifies the difference between +IN and -IN, and outputs the OUTPUT signal. FIG. 6 is a circuit schematic diagram of the filter circuit. The filter circuit is a band-pass filter circuit, which band-pass filters the amplified OUTPUT signal and outputs the AD_IN signal. A transformer core ground current detection device based on the Internet of Things technology of the present invention transmits the AD_IN signal to the AD sampling chip. For the processing operation of the single-chip microcomputer control circuit.

The signal conditioning circuit conditions the analog current signal into a digital signal suitable for processing by the core processing unit of the microcontroller control circuit. The ZIGBEE terminal node module on the core processing unit transmits the processed data to the wireless communication unit, and the wireless communication unit transmits the collected ground current to the remote monitoring center unit through TCP\IP.

Optimized, the remote monitoring platform monitors the current data collected by the transformer core current sensor in real time. For the alarm data, through wireless transmission, the remote monitoring platform sends the alarm information to the mobile phone of the designated responsible person set in the database in the form of an alarm message .

The method for detecting the ground current of a transformer iron core based on the Internet of Things technology of the present invention realizes real-time online monitoring, can detect problems in time, and ensures the normal operation of the power grid, and has good application prospects.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (7)

1. A transformer iron core grounding current detection method based on Internet of Things technology, is characterized in that, comprises the steps: (1) Several transformer core current sensors are correspondingly installed on the flat steel grounding wire to be tested, and the analog current signals on the corresponding grounding wire are respectively collected; (2) The transformer core ground current detection device based on the Internet of Things technology is connected with the transformer core current sensor by communication. The transformer core ground current detection device based on the Internet of Things technology has a built-in single-chip control circuit, ZIGBEE communication module and wireless communication circuit. The ZIGBEE network is a network for several transformer core current sensors; (3) The transformer core current sensor converts the detected current signal into a differential voltage output through the I/V conversion circuit in the transformer core grounding current detection device based on Internet of Things technology; (4) amplifying the differential voltage signal output by step (3) through a differential voltage amplifier circuit; (5) the voltage signal amplified in step (4) is filtered through a filter circuit; (6) the signal after step (5) processing is sent to the AD acquisition unit of the core processing unit of the single-chip microcomputer control circuit; (7) the core processing unit of single-chip microcomputer control circuit carries out FFT spectrum analysis to the signal that step (6) collects and calculates the iron core current size; (8) The core processing unit of the single-chip microcomputer control circuit periodically stores the data collected; (9) The core processing unit of the single-chip microcomputer control circuit responds to the data call of the remote monitoring platform, and uploads the collected iron core current to the remote monitoring platform through the wireless communication unit. 2. A kind of transformer iron core grounding current detection method based on Internet of Things technology according to claim 1, is characterized in that: described remote monitoring platform real-time monitors the electric current data that transformer iron core current sensor collects, and to alarm data, through Wireless transmission, the remote monitoring platform sends the alarm information to the mobile phone of the designated responsible person set in the database in the form of an alarm message. 3. A transformer core ground current detection method based on the Internet of Things technology according to claim 1, characterized in that: the transformer core ground current detection device based on the Internet of Things technology has a built-in single-chip microcomputer control circuit and a signal conditioning circuit , a clock module, a ZIGBEE communication module, a data storage circuit, a wireless communication module, a serial communication interface circuit and a power supply circuit for supplying power to the above-mentioned circuit, the single-chip control circuit is an embedded system composed of a microprocessor chip and its peripheral circuits, The signal output terminal of the microprocessor chip is electrically connected with signal conditioning circuit, clock module, ZIGBEE communication module, data storage circuit, wireless communication module, serial port communication interface circuit and signal input terminal of the power supply circuit. 4. A transformer core grounding current detection method based on the Internet of Things technology according to claim 3, characterized in that: the microprocessor chip is a CORTEX-M3 processor. 5. A transformer core ground current detection method based on the Internet of Things technology according to claim 3, characterized in that: the signal conditioning circuit includes an I/V conversion circuit, a differential amplifier circuit and a filter circuit, and the transformer The current signal collected by the core current sensor is processed by the I/V conversion circuit, the differential amplifier circuit and the filter circuit, and then sent to the AD acquisition circuit of the single-chip control circuit for processing and operation by the single-chip control circuit. 6. A transformer core grounding current detection method based on the Internet of Things technology according to claim 3, characterized in that: the serial communication interface circuit is a MAX485 interface circuit, and the transformer core grounding based on the Internet of Things technology The current detection device is electrically connected with the transformer core current sensor through the RS485 bus. 7. A transformer core grounding current detection method based on the Internet of Things technology according to claim 3, characterized in that: the transformer core current sensor is a split current sensor.