CN216900683U

CN216900683U - Miniature Rogowski coil metering device

Info

Publication number: CN216900683U
Application number: CN202122640573.9U
Authority: CN
Inventors: 费鑫杰; 沈梦佳; 周伟
Original assignee: Zhejiang Yongtailong Electronic Co ltd
Current assignee: Zhejiang Yongtailong Electronic Co ltd
Priority date: 2021-10-29
Filing date: 2021-10-29
Publication date: 2022-07-05
Anticipated expiration: 2031-10-29

Abstract

The utility model provides a miniature Rogowski coil metering device which comprises an integrated circuit, and specifically comprises a power supply circuit, a sampling circuit, a communication circuit, a metering circuit and an LED indicating circuit, wherein the power supply circuit is respectively connected with the communication circuit and the metering circuit and outputs a low-voltage power supply to the communication circuit and the metering circuit, the communication circuit and the metering circuit are mutually communicated and are both connected with the LED indicating circuit, the sampling circuit comprises a voltage sampling circuit and a current sampling circuit and is connected with the metering circuit, and the current sampling circuit comprises Rogowski coil sampling input. The utility model can be matched with a circuit breaker or an air switch, has an integrated design, can realize functions of metering, alarming and the like with extremely small volume, is based on Rogowski coil sampling, and has the characteristics of real-time measurement of current, high response speed and small phase error.

Description

Miniature Rogowski coil metering device

Technical Field

The utility model belongs to the technical field of metering modules, and particularly relates to a miniature Rogowski coil metering device.

Background

In order to achieve the goals of carbon peak-to-peak and carbon neutralization, real-time effective monitoring of high-power equipment will become normal. Meanwhile, the real-time data can also make the high-power equipment become a part of the everything interconnection. In enterprises or families, the monitoring of each device and household appliance can effectively predict potential safety hazards and search for abnormalities.

In the era of the world of the vast Internet of things of the electric equipment at present, metering parameters and operating states enter a network as indispensable elements of the electric equipment, and the requirement cannot be met necessarily under the condition that only a summary table is accessed no matter in a factory or a family, so that various sensors are produced at the same time; for the electric equipment, if the metering can be realized by directly mounting the interface, the popularization of the Internet of things is greatly facilitated. Along with the continuous abundance and variety of customer demands in recent years, the integrated design is pushed up the wave tip, and the integrated design has satisfied diversified demand, also can save wiring space, the user of being convenient for installs. However, most of the existing metering devices on the market are large in size, heavy in weight, complex to install and high in cost.

Disclosure of Invention

The utility model aims to solve the problems, and provides a miniature Rogowski coil metering device which can be conveniently and directly mounted for use with an extremely small size, is convenient for a user to directly mount, has no exposed terminal except an external power supply wire, and is safer and more reliable.

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

the utility model provides a miniature rogowski coil metering device, includes integrated circuit, specifically includes power supply circuit, sampling circuit, communication circuit, metering circuit and LED indicating circuit, power supply circuit connects communication circuit and metering circuit respectively and exports low voltage power to communication circuit and metering circuit, communication circuit and metering circuit intercommunication are connected and are all connected LED indicating circuit, sampling circuit includes voltage sampling circuit and current sampling circuit and connects metering circuit, current sampling circuit includes the sampling input of rogowski coil. The metering device can be used for electric energy metering, does not occupy space, can predict the problem of current overload in advance, can greatly reduce the installation volume of the metering device through the Rogowski coil, can be matched with a micro Rogowski coil metering device for metering by high-power equipment, can be directly upgraded on the basis of the existing equipment by matching with the design of high integration of the periphery, and realizes metering monitoring.

Furthermore, the power supply circuit comprises a resistance-capacitance voltage reduction circuit and a DC-DC voltage reduction circuit, wherein the resistance-capacitance voltage reduction circuit comprises a first input end, a patch capacitor, a patch resistor, an alternating current-direct current bridge, a voltage stabilizing diode and a first output end which are sequentially connected. The power circuit of the utility model adopts a mode of combining resistance-capacitance voltage reduction and DC-DC voltage reduction, can ensure higher output power under the condition of using a small-volume capacitor, and greatly reduces the volume of the whole power supply.

Further, the DC-DC voltage reduction circuit comprises a second input end, a DC-DC voltage reduction chip and a second output end; the first input end is connected with an input power supply, the output voltage of the first output end is the input voltage of the second input end, and the second output end outputs a 3.3V power supply. The utility model reduces the conventional input power supply to 3.3V output in two times, and can effectively amplify large current when the DC-DC voltage is reduced for the second time.

Further, the voltage sampling circuit comprises a voltage division circuit connected with the input power supply, and the voltage sampling circuit outputs a voltage sampling source to the metering circuit; the Rogowski coil is connected with and outputs a current sampling source to the metering circuit through the connector. The voltage sampling of the utility model uses a voltage division mode, and the current sampling adopts Rogowski coil input, thus being capable of increasing the power of the power supply and simultaneously ensuring the precision.

Further, the communication circuit comprises a bluetooth SOC circuit, and the bluetooth SOC circuit comprises a bluetooth low energy chip and a PCB antenna which are connected to each other. The utility model can better save space by adopting the PCB antenna.

Further, the bluetooth low energy chip includes ST17H66 of a 32-bit processor with low energy consumption. According to the utility model, an ST17H66 of a low-power 32-bit processor is adopted, the chip integrates a BLE5.2 protocol, and external equipment or a mobile phone can also be directly connected through Bluetooth to read real-time metering parameters and electric quantity data.

Furthermore, the metering circuit comprises a sampling metering chip supporting Rogowski coil metering and an active crystal oscillator connected with the sampling metering chip, and the metering circuit outputs an indicating electric energy metering pulse. The utility model adopts the sampling and metering chip and is provided with the active crystal oscillator, thereby not only supporting Rogowski coil metering, but also providing voltage, current, various powers, pulse output and the like, having the function of harmonic analysis and better monitoring the state of a power grid.

Furthermore, the Bluetooth SOC circuit is in communication connection with the metering circuit through the UART. The UART is used for communication, only two lines are used for realizing the communication, the connection relation is simple, and the integration is convenient.

Further, the LED indicating circuit comprises a double-color LED, and the double-color LED comprises an indicating and metering lamp connected with an indicating electric energy metering pulse and a communication state lamp connected with a low-power consumption Bluetooth chip. The utility model respectively indicates the metering state and the communication state through the indicating metering lamp and the communication state lamp, and is convenient for visually obtaining the metering state and the running state of the device.

Compared with the prior art, the utility model has the advantages that:

1. the micro Rogowski coil metering device can be matched with a circuit breaker or an air switch, or an electric energy metering module with Bluetooth used by electric equipment, has an integrated design, can realize functions of metering, alarming and the like by using a very small volume, is based on Rogowski coil sampling, and has the characteristics of real-time current measurement, high response speed and small phase error;

2. the utility model adopts voltage two-stage voltage reduction, greatly reduces the volume of the power supply, and can realize the function of measuring large current with small volume by combining with the small volume of the Rogowski coil;

3. the BLE5.2 technology is adopted, the power consumption and the cost are obviously reduced while the same communication range is kept, and the centralized reading of the mesh network and the direct reading of the mobile phone are supported;

4. the utility model adopts a non-terminal design, can be installed by only externally connecting a voltage wire and passing through a tube current, and can be conveniently installed at the rear end of the existing circuit breaker and the front end of an electric appliance.

Additional advantages, objects, and features of the utility model will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the utility model.

Drawings

FIG. 1 is a schematic structural diagram of a micro Rogowski coil metering device of the present invention;

FIG. 2 is a circuit diagram of the power supply circuit of the present invention;

FIG. 3 is a circuit diagram of a sampling circuit of the present invention;

FIG. 4 is a circuit diagram of the communication circuit of the present invention;

FIG. 5 is a circuit diagram of the metering circuit of the present invention;

fig. 6 is a circuit diagram of an LED indicating circuit of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

As shown in fig. 1, the micro rogowski coil metering device of the present embodiment includes an integrated circuit, and specifically includes a power supply circuit, a sampling circuit, a communication circuit, a metering circuit and an LED indicating circuit, the power supply circuit connects the communication circuit and the metering circuit respectively and outputs a low voltage power supply to the communication circuit and the metering circuit, the communication circuit and the metering circuit are connected in communication with each other and are both connected to the LED indicating circuit, the sampling circuit includes a voltage sampling circuit and a current sampling circuit and is connected to the metering circuit, and the current sampling circuit includes a rogowski coil sampling input. The embodiment can be used for electric energy metering and predicting current overload in advance, does not occupy space, can realize the function of the metering device, can greatly reduce the installation volume of the metering device through the Rogowski coil, can be matched with the small Rogowski coil for metering by high-power equipment, is matched with the design of peripheral high integration, can be directly upgraded on the basis of the existing equipment, and realizes metering monitoring.

As shown in fig. 2, the power circuit of this embodiment includes a resistance-capacitance voltage-reducing circuit and a DC-DC voltage-reducing circuit, where the resistance-capacitance voltage-reducing circuit includes a first input terminal, a patch capacitor, a patch resistor, an ac/DC bridge, a zener diode, and a first output terminal, which are connected in sequence. The power circuit of the embodiment adopts a mode of combining resistance-capacitance voltage reduction and DC-DC voltage reduction, can use a lower capacitor, ensures higher output power and greatly reduces the volume of the whole power supply.

The DC-DC voltage reduction circuit of the embodiment comprises a second input end, a DC-DC voltage reduction chip and a second output end; the first input end is connected with a 220V alternating current input power supply, the output voltage of the first output end is the input voltage of the second input end, and the second output end outputs a 3.3V power supply.

The power supply of the embodiment adopts a mode of combining resistance-capacitance voltage reduction and DC-DC voltage reduction, reduces 220V alternating current of the power supply to 30V twice respectively, and then reduces the alternating current from 30V to 3.3V for output; compared with the conventional rc step-down to 15V and then the LDO step-down to 3.3V, the same output current I is obtained at 30V and 15V, and the DC-DC secondary step-down of the present embodiment can obtain 30/3.3 × 0.8-7.2 times of current amplification at 80% efficiency. Therefore, a lower C2 capacitor can be used, higher output power is ensured, and the size of the whole power supply is greatly reduced. The size of the safety capacitor can no longer be the limit of blocking the resistance-capacitance voltage reduction power; the power consumption of the whole module can be greatly reduced.

The power supply circuit of the embodiment takes the networks "L" and "N" as the power supply input of the whole miniature Rogowski coil metering device, and the network "VDD" as the output of the low-voltage power supply, so that power can be provided for the communication circuit and the metering circuit.

The DC-DC buck chip of this embodiment is selected from JW5018, and devices with the same voltage and power range, such as V5500, SY8263(DCDC converter), FT3084, etc., may be selected by a user according to requirements and other factors.

As shown in fig. 3, the present embodiment includes a voltage divider circuit connected to an input power source, and a voltage sampling circuit outputting a voltage sampling source to a metering circuit; the Rogowski coil is connected with and outputs a current sampling source to the metering circuit through the connector.

The voltage sampling of the embodiment uses a voltage division mode; the current sampling adopts Rogowski coil input. The embodiment is different from the conventional resistance-capacitance voltage reduction measurement, adopts the mode of front-end half-wave rectification and rear-end live wire as the measurement reference ground, adopts the mode of power full-wave rectification and intermediate voltage sampling, and ensures the precision while increasing the power of the power supply.

The left side of fig. 3 is a voltage sampling line, networks "L" and "N", and with power input, outputs "UP" and "GND" as sampling sources to be provided to the metering AFE module as voltage sampling; the right side is a Rogowski coil current sampling line, the Rogowski coil is connected by J1, and IAP and IAN are output to a metering AFE module to be used as current sampling.

As shown in fig. 4, the communication circuit of the present embodiment includes a bluetooth SOC circuit including a bluetooth low energy chip and a PCB antenna connected to each other. The bluetooth low energy chip includes ST17H66 which is a 32-bit low energy processor.

This embodiment bluetooth SOC is the master control, adopts ST17H66, and this chip is 32 bit processors of low-power consumption, integrated BLE5.2 agreement, and external equipment or cell-phone can directly connect through the bluetooth, read real-time measurement parameter and electric quantity data. Pins are TX2 and RX2 in fig. 4, respectively; the Bluetooth SOC circuit is supplied by a 3.3V power supply provided by VDD; the use of PCB antennas may provide better space savings. The SOC in this embodiment may be selected from ST17H65 of the same brand.

As shown in fig. 5, the metering circuit of the present embodiment includes a sampling metering chip supporting the metering of the rogowski coil and an active crystal oscillator connected to the sampling metering chip, and the metering circuit outputs a metering pulse indicating electric energy.

The metering circuit of the embodiment is a metering AFE module, is supplied by a 3.3V power supply provided by VDD, mainly adopts a V9360 voltage and current sampling metering chip, can support Rogowski coil metering, can also provide voltage, current, various powers, pulse output and the like, has a harmonic analysis function, and can better monitor the state of a power grid. In fig. 5, IAN and IAP are current sampling inputs, and UAP and GND are voltage sampling inputs. RX2 and TX2 are responsible for communicating with the master Bluetooth SOC, and CF1 outputs a pulse indicating power metering.

The Bluetooth SOC circuit of the embodiment is in communication connection with the metering circuit through the UART. The UART is used for communication, only two lines are used for realizing the communication, the connection relation is simple, and the integration is convenient.

As shown in fig. 6, the LED indicating circuit of the present embodiment includes a two-color LED, where the two-color LED includes an indicating and metering lamp connected to indicate an electric energy metering pulse and a communication status lamp connected to a bluetooth low energy chip. The embodiment uses the double-color LED to respectively indicate the metering state and the communication state through the CF1 and the CF2-1, so as to observe the running state of the device and conveniently and intuitively obtain the metering state and the running state of the device.

The Rogowski coil is adopted for sampling, the Rogowski coil does not contain ferromagnetic materials, has no hysteresis effect, almost zero phase error and no magnetic saturation phenomenon, so that the measuring range can be from a plurality of amperes to hundreds of kiloamperes of current, the structure is simple, direct circuit connection does not exist between the measuring range and the current to be measured, and the response frequency band is wide from 0.1Hz to 1 MHz; compared with the traditional mutual inductor with the iron core, the Rogowski coil has the advantages of wide measurement range, high precision, stability, reliability, wide response frequency band, small volume, light weight, safety and environmental protection.

The micro Rogowski coil metering device can be used for metering electric energy and predicting current overload in advance at the rear end of a metering circuit breaker or the rear end of an air switch and in front of various electric equipment, can conveniently search the reason for breaking the circuit breaker or the air switch, does not occupy space, and can realize functions. The micro Rogowski coil metering device can also be used as a networking metering terminal or an independent metering device, and various information of corresponding electric equipment can be directly read through a mobile phone.

The specific embodiments described herein are merely illustrative of the spirit of the utility model. Various modifications or additions may be made to the described embodiments, or alternatives may be employed, by those skilled in the art, without departing from the spirit or ambit of the utility model as defined in the appended claims.

Claims

1. The utility model provides a miniature Rogowski coil metering device, includes integrated circuit, its characterized in that specifically includes power supply circuit, sampling circuit, communication circuit, measurement circuit and LED indicating circuit, power supply circuit connects communication circuit and measurement circuit respectively and exports low voltage power to communication circuit and measurement circuit, communication circuit and measurement circuit intercommunication are connected and are all connected LED indicating circuit, sampling circuit includes voltage sampling circuit and current sampling circuit and connects measurement circuit, current sampling circuit includes the sampling input of Rogowski coil.

2. The miniature Rogowski coil metering device according to claim 1, wherein the power circuit comprises a resistance-capacitance voltage-reducing circuit and a DC-DC voltage-reducing circuit, and the resistance-capacitance voltage-reducing circuit comprises a first input end, a chip capacitor, a chip resistor, an AC/DC bridge, a voltage-stabilizing diode and a first output end which are connected in sequence.

3. The miniature rogowski coil metering device of claim 2, wherein the DC-DC voltage reduction circuit comprises a second input terminal, a DC-DC voltage reduction chip and a second output terminal; the first input end is connected with an input power supply, the output voltage of the first output end is the input voltage of the second input end, and the second output end outputs a 3.3V power supply.

4. The miniature rogowski coil metering device of claim 1, wherein the voltage sampling circuit comprises a voltage dividing circuit connected with an input power supply, and the voltage sampling circuit outputs a voltage sampling source to the metering circuit; the Rogowski coil is connected with and outputs a current sampling source to the metering circuit through the connector.

5. The miniature Rogowski coil metering device of claim 1, wherein the communication circuit comprises a Bluetooth SOC circuit comprising a Bluetooth Low energy chip and a PCB antenna connected to each other.

6. The miniature Rogowski coil metering device of claim 5, wherein the Bluetooth low energy chip comprises a 32-bit low energy processor ST17H 66.

7. The miniature Rogowski coil metering device of claim 6, wherein the Bluetooth SOC circuit is communicatively connected to the metering circuit via a UART.

8. The miniature Rogowski coil metering device as claimed in claim 5, wherein the metering circuit comprises a sampling metering chip supporting Rogowski coil metering and an active crystal oscillator connected with the sampling metering chip, and the metering circuit outputs a metering pulse indicating electric energy.

9. The miniature Rogowski coil metering device of claim 8, wherein the LED indicating circuit comprises a two-color LED, the two-color LED comprising an indicating metering lamp connected to indicate the electric energy metering pulse and a communication status lamp connected to the Bluetooth low energy chip.