CN113447083A

CN113447083A - Single-coil passive wireless current temperature detection device

Info

Publication number: CN113447083A
Application number: CN202110894977.2A
Authority: CN
Inventors: 蔡楚彬; 刘迪凯; 叶皓贲
Original assignee: Guangzhou Cells Net Electronic Technology Co ltd
Current assignee: Guangzhou Cells Net Electronic Technology Co ltd
Priority date: 2021-08-05
Filing date: 2021-08-05
Publication date: 2021-09-28

Abstract

The invention discloses a single-coil passive wireless current temperature detection device which comprises a relay, a current mutual inductor, a power taking module, a current measurement module, a temperature measurement module, a microprocessor, a wireless sending module and a button battery. The current mutual inductance coil acts on the electricity taking module and the current measuring module respectively through the switching of the relay, and the functions of taking electricity and measuring current by the single coil are achieved. The conventional passive wireless current temperature detection device generally uses a double coil for respectively taking electricity and measuring or uses a single coil for simultaneously taking electricity and measuring. The invention only uses the single coil to respectively supply power to the system and measure the current, so that the circuit design is simpler, the product volume is small, the current measurement precision is high, and the current measurement range is large.

Description

Single-coil passive wireless current temperature detection device

Technical Field

The invention relates to the technical field of power cable monitoring, in particular to a single-coil passive wireless current temperature detection device.

Background

In order to prevent premature aging of the cable insulation and to ensure safe operation of the cable, the cable line should be operated without exceeding the specified long-term permissible ampacity, and overloading is a major hazard to safe operation of the cable line. The aged cable may have its insulation broken, causing partial discharge, causing excessive surface temperature, and possibly causing fire. The operation department must monitor the current and surface temperature of the cable in real time so as to adjust and reduce the load in an emergency when the system is in fault or abnormal condition and ensure that the cable operates according to the specified current-carrying capacity.

At present, a passive wireless online monitoring device capable of monitoring the current and the temperature of a cable simultaneously has two modes, one mode is that two groups of mutual inductors are adopted, one group is used for getting electricity, and the other group is used for measuring the current; the other is to use a group of mutual inductors to simultaneously take power and measure current. The two modes can solve the problems of difficult power supply and high-low voltage safety isolation of monitoring equipment in a high-voltage strong magnetic environment, but the two groups of mutual inductors have larger volume and high cost; the single coil is used for simultaneously taking power and measuring current, and the measuring current is influenced due to fluctuation of a load circuit, so that the measuring precision of the current is reduced.

Disclosure of Invention

The invention aims to provide a single-coil passive wireless current temperature detection device, which aims to solve the problems that the prior passive wireless online monitoring device capable of monitoring the current and the temperature of a cable simultaneously is provided in the background technology, and generally has two modes, one mode is that two groups of mutual inductors are adopted, one group is used for getting electricity, and the other group is used for measuring the current; the other is to use a group of mutual inductors to simultaneously take power and measure current. The two modes can solve the problems of difficult power supply and high-low voltage safety isolation of monitoring equipment in a high-voltage strong magnetic environment, but the two groups of mutual inductors have larger volume and high cost; the single coil is used for simultaneously taking power and measuring current, and the measuring current is influenced due to fluctuation of a load circuit, so that the measuring precision of the current is reduced.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a single coil passive wireless current temperature-detecting device, includes relay, current mutual inductance coil, gets electric module, current measurement module, temperature measurement module, microprocessor, wireless sending module, button cell. Current mutual inductance coil is connected to the common terminal of relay, the electric module is got in relay normally closed contact connection, convert the electric current that the coil sensed into voltage storage and get in the energy storage electric capacity of electric module, after energy storage electric capacity reached rated voltage, the relay switches to the current measurement module, the system is supplied power by energy storage electric capacity this moment, the current measurement module turns into the ADC voltage that microprocessor can gather with the electric current that the coil sensed, the normally closed contact is continued to dial again to the relay, the electric current that the coil sensed continues to be used for the power supply, after the temperature was gathered to temperature measurement module simultaneously, microprocessor handled the data of gathering, pass through wireless sending module with real-time current and temperature on the cable and transmit to the monitoring platform.

Preferably, the relay is used for switching the power taking module and the measuring module, so that the power supply and the measuring of the system are realized by using the single coil.

Preferably, the current transformer coil is used for inducing current on the cable.

Preferably, the power taking module comprises a clamping circuit, a rectifying and filtering circuit, an energy storage capacitor and a DC-DC module, and is used for converting a current signal induced by the coil into a stable direct current voltage.

Preferably, the current measuring module is used for converting the current induced by the current transformer coil into an ADC voltage which can be collected by the microprocessor.

Preferably, the temperature measuring module collects the surface temperature of the cable through an infrared temperature sensor.

Preferably, the microprocessor is configured to process the collected current and temperature data.

Preferably, the wireless sending module is used for realizing data transmission.

Preferably, the button battery is used as a standby battery, no-load or load current is less than starting current, and the button battery is used for supplying power to keep a working state.

Compared with the prior art, the invention has the beneficial effects that: the single coil is used for respectively supplying power to the system and measuring current, so that the problems of large volume and high cost of two groups of mutual inductors are solved; the single coil is used for simultaneously taking power and measuring current, and the measuring current is influenced due to fluctuation of a load circuit, so that the measuring precision of the current is reduced. The circuit design is simpler, and the product is small, and current measurement precision is high simultaneously, and measuring range is big.

Detailed Description

The technical solutions in the embodiments of the present patent will be clearly and completely described below with reference to the drawings in the embodiments of the present patent, and it is obvious that the described embodiments are only some embodiments of the present patent, not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the scope of protection of this patent.

This patent provides a technical scheme:

referring to fig. 1, the common terminal of the relay is connected to a current transformer coil, which can act on the power-taking module and the current-measuring module, respectively, when the switch is switched. The power taking module is connected with the microprocessor. The current measuring module and the temperature measuring module are respectively connected with the microprocessor. The wireless sending module is connected with the microprocessor, and the button cell is connected with the microprocessor.

Referring to fig. 2, the power-taking module includes a clamping circuit, a rectifying and filtering circuit, an energy storage capacitor, and a DC-DC module.

The working principle is that the common end of the relay is connected with the coil, the normally closed contact of the relay is connected with the power taking module, the alternating voltage induced by the coil is limited in a certain voltage range through the clamping circuit, the direct voltage is obtained after the alternating voltage passes through the rectifying and filtering circuit, the electric energy is stored in the energy storage capacitor, and meanwhile, the voltage converts the higher voltage obtained after the clamping rectification into stable 3.3V through the DC-DC module to supply power to the microprocessor. When the fact that the energy storage capacitor reaches rated voltage is detected, a switch of the relay is dialed to the current measuring module, the system is powered by the energy storage capacitor at the moment, the current measuring module converts sensed current into ADC voltage which can be collected by the microprocessor through a sampling resistor, the relay continues to be dialed to the normally closed contact, meanwhile, data collected by the infrared temperature sensor are converted into current and temperature through processing of the microprocessor, and the wireless sending module sends the processed data out. The button battery is used as a standby battery, no-load or load current is less than starting current, and the button battery is used for supplying power to keep a working state.

Finally, it should be noted that the above-mentioned patent solutions are only used for illustrating the patent, not for limiting the protection scope of the patent, and those skilled in the art can make simple modifications or equivalent substitutions on the patent solutions without departing from the spirit and scope of the patent solutions.

Claims

1. The invention discloses a single-coil passive wireless current temperature detection device which comprises a relay, a current mutual inductor, a power taking module, a current measurement module, a temperature measurement module, a microprocessor, a wireless sending module and a button battery.

2. The single-coil passive wireless current temperature sensing device of claim 1, wherein: the relay is used for switching the power taking module and the measuring module so as to realize the power supply and the measuring effect of the single coil on the system respectively.

3. The single-coil passive wireless current temperature sensing device of claim 1, wherein: the current mutual inductor is used for inducing current on the cable.

4. The single-coil passive wireless current temperature sensing device of claim 1, wherein: the power taking module comprises a clamping circuit, a rectifying and filtering circuit, an energy storage capacitor and a DC-DC module and is used for converting current signals induced by the coil into stable direct current voltage.

5. The single-coil passive wireless current temperature sensing device of claim 1, wherein: the current measuring module is used for converting the current induced by the current mutual inductance coil into ADC voltage which can be collected by the microprocessor.

6. The single-coil passive wireless current temperature sensing device of claim 1, wherein: the temperature measuring module collects the surface temperature of the cable through the infrared temperature sensor.

7. The single coil wire flow and temperature measuring device of claim 1, wherein: the microprocessing is used for processing the acquired data of the current and the temperature.

8. The single-coil passive wireless current temperature sensing device of claim 1, wherein: the wireless sending module is used for realizing data transmission.

9. The single-coil passive wireless current temperature sensing device of claim 1, wherein: the button battery is used as a standby battery, no-load or load current is less than starting current, and the button battery is used for supplying power to keep a working state.