CN112305303A

CN112305303A - Three-phase guide rail type multifunctional wireless electric energy metering terminal

Info

Publication number: CN112305303A
Application number: CN202011053964.4A
Authority: CN
Inventors: 谷雨霖
Original assignee: Nanjing Zijin Sports Industry Corp ltd
Current assignee: Nanjing Zijin Sports Industry Corp ltd
Priority date: 2020-09-29
Filing date: 2020-09-29
Publication date: 2021-02-02

Abstract

The invention belongs to the technical field of electric energy data acquisition equipment, and particularly relates to a three-phase guide rail type multifunctional wireless electric energy metering terminal which comprises a terminal body, wherein a single chip microcomputer, a three-phase electric energy measuring module, a communication module, an LORA module, a miniature current transformer, a miniature voltage transformer and a power management module are arranged in the terminal body, and the miniature current transformer and the miniature voltage transformer are respectively connected with the three-phase electric energy measuring module. The invention can measure positive and reverse active electric energy, input and output reactive electric energy, can measure A, B, C three-phase voltage, three-phase current, each phase and total active power, reactive power, power factor and power grid frequency, and has the function of recording the maximum demand; the electric energy is respectively accumulated and stored according to the existence, the idle work, the positive direction, the reverse direction, the peak, the flat direction and the valley, the electric energy data freezing function is realized (the default freezing time is 24 hours at the end of each month), and the freezing data of 12 months can be stored in the table.

Description

Three-phase guide rail type multifunctional wireless electric energy metering terminal

Technical Field

The invention relates to the technical field of electric energy data acquisition equipment, in particular to a three-phase guide rail type multifunctional wireless electric energy metering terminal.

Background

The traditional power data acquisition uses a wired communication mode, and a cable is required to be deployed for establishing the wired communication mode, so that a large amount of manpower and material resources are required, and the current labor cost is higher and higher; the wireless data transmission mode is used only by connecting a wireless data transmission radio station to each terminal and erecting an antenna with proper height. In contrast, the wireless data transmission module is used for establishing a special wireless data transmission mode, so that manpower and material resources are saved, and investment is saved considerably.

Especially when remote stations with a distance of several kilometers are required to be connected with each other for communication, long-distance cables must be erected or long cable trenches must be excavated by adopting a wired mode, the engineering period may need several months, and the special wireless data transmission mode established by the data transmission module only needs to erect an antenna with a proper height, and the engineering period only needs several days.

If WIFI is used as a wireless transmission mode, although the wireless transmission mode has the advantage of high speed, the problems of high power consumption and short transmission distance need to be solved. The data volume is small in the field of industrial internet, and the requirement for high speed and high bandwidth is avoided. If NB-IoT is used to implement the scheme, the base station at the deployment location of the operator is required to be provided with an IoT module, supporting NB-IoT functionality. The use of NB-IoT/4G requires the transmission path of the operator, which causes additional cost and low cost performance in the scenario that a plurality of devices need to be networked.

At present, split DTU data are sold in the market, although the DTU and the traditional intelligent electric meter are combined, the cost can be saved, the defect of large volume exists in the combined scheme, the general DTU at least needs to occupy the guide rail position of 2P in actual construction, and the installation of a narrow distribution box in space is inconvenient.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a three-phase guide rail type multifunctional wireless electric energy metering terminal, which solves the problems of higher data transmission cost, large volume and inconvenient installation of the existing electric energy metering equipment.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a multi-functional wireless electric energy measurement terminal of three-phase guide tracked, includes the terminal body, the inside of terminal body is equipped with singlechip, three-phase electric energy measurement module, communication module, LORA module, miniature current transformer, miniature voltage transformer and power management module, miniature current transformer and miniature voltage transformer are connected with three-phase electric energy measurement module respectively, miniature current transformer and miniature voltage transformer are used for measuring alternating current value and alternating current voltage value respectively, three-phase electric energy measurement module, communication module and LORA module are connected with the singlechip respectively, three-phase alternating current is connected to power management module, power management module is used for providing working power supply to singlechip, three-phase electric energy measurement module, communication module and LORA module.

As a preferred technical scheme of the invention, the single chip microcomputer adopts a V9911 electric energy metering SOC chip.

As a preferred technical scheme of the present invention, the three-phase electric energy measurement module is configured to sample an ac current value and an ac voltage value measured by the micro current transformer and the micro voltage transformer, perform electric energy calculation, and store electric energy parameters, the three-phase electric energy measurement module employs a V9203 three-phase metering chip, and the three-phase electric energy measurement module performs data exchange with the single chip microcomputer through an SPI communication interface.

As a preferred technical scheme of the invention, the communication module adopts a V6602 chip to complete RS-485 communication.

As a preferred technical solution of the present invention, the LORA module employs an LORA spread spectrum communication chip SX1278 of SEMTECH, which is used to implement a wireless data transmission function of the device.

As a preferred technical solution of the present invention, the micro current transformer is CT 128B.

As a preferable technical scheme of the invention, the miniature voltage transformer is of a TV1005M type.

As a preferred technical scheme of the invention, the power management module is composed of AS1117-5 and AS1117-3.3 chips and respectively outputs 3.3V and 5V direct-current voltages to provide a working power supply for the chips in the wireless electric energy metering terminal system.

As a preferred technical solution of the present invention: the wireless electric energy metering terminal also comprises a ferroelectric memory FM24C64B, a crystal oscillator and a key which are electrically connected with the single chip microcomputer.

(III) advantageous effects

Compared with the prior art, the invention provides a three-phase guide rail type multifunctional wireless electric energy metering terminal which has the following beneficial effects:

1. the terminal can measure positive and reverse active electric energy, input and output reactive electric energy, can measure A, B, C three-phase voltage, three-phase current, each phase and total active power, reactive power, power factor and power grid frequency, and has the function of recording the maximum demand; the electric energy is respectively accumulated and stored according to the existence, the idle work, the positive direction, the reverse direction, the peak, the flat direction and the valley, the electric energy data freezing function is realized (the default freezing time is 24 hours at the end of each month), and the freezing data of 12 months can be stored in the meter; all stored data are not lost after power failure and can be kept for more than 10 years.

2. This multi-functional wireless electric energy measurement terminal of three-phase guide tracked, the LCD display screen has been configured, the clock can be carried out, rate period isoparametric sets, electric energy pulse output function has, support RS485 communication and LORA wireless communication function, can convenience of customers carries out the power consumption monitoring management, it is high to have the precision, small, advantages such as simple to operate, support DIN35 standard guide rail, can install in all kinds of block terminals in a flexible way (metal block terminal need with the sucking disc antenna outside as for the block terminal), realize rapidly that the branch electric energy measurement to different regions and different loads, statistics and analysis.

3. This multi-functional wireless electric energy measurement terminal of three-phase guide tracked, the user can set up equipment internal parameter according to on-the-spot actual conditions, can extensively be used for fields such as all kinds of enterprises, house, intelligent building, collection trade market and dormitory, school, especially all kinds of power consumption monitoring fields, and application scope is wide.

Drawings

FIG. 1 is a schematic block diagram of the system of the present invention;

FIG. 2 is a working circuit of the single chip microcomputer in the invention;

FIG. 3 is a schematic diagram of a voltage sampling loop of a three-phase power measuring module according to the present invention;

FIG. 4 is a schematic diagram of a current sampling loop of a three-phase power measuring module according to the present invention;

FIG. 5 is a schematic structural diagram of a communication module according to the present invention;

FIG. 6 is a schematic diagram of an operating circuit of the communication module of the present invention;

FIG. 7 is a schematic diagram of a modulation circuit of the LORA module of the present invention;

FIG. 8 is a second schematic diagram of a modulation circuit of the LORA module of the present invention;

FIG. 9 is a circuit diagram illustrating the operation of the power management module outputting 3.3V and 5V voltages, respectively, according to the present invention;

fig. 10 is a schematic structural view of a terminal body according to the present invention.

In the figure: 100. a terminal body; 101. a single chip microcomputer; 102. a three-phase electric energy measuring module; 103. a communication module; 104. a LORA module; 105. a micro current transformer; 106. a miniature voltage transformer; 107. and a power management module.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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 protection scope of the present invention.

Examples

Referring to fig. 1-10, the present invention provides the following technical solutions: the utility model provides a multi-functional wireless electric energy measurement terminal of three-phase guide tracked, including terminal body 100, terminal body 100's inside is equipped with singlechip 101, three-phase electric energy measurement module 102, communication module 103, LORA module 104, miniature current transformer 105, miniature voltage transformer 106 and power management module 107, miniature current transformer 105 and miniature voltage transformer 106 are connected with three-phase electric energy measurement module 102 respectively, miniature current transformer 105 and miniature voltage transformer 106 are used for measuring alternating current value and alternating current voltage value respectively, three-phase electric energy measurement module 102, communication module 103 and LORA module 104 are connected with singlechip 101 respectively, power management module 107 connects the three-phase alternating current, power management module 107 is used for providing working power to singlechip 101, three-phase electric energy measurement module 102, communication module 103 and LORA module 104.

Specifically, the single chip microcomputer 101 adopts a V9911 electric energy metering SOC chip.

In this embodiment, V9911 is a high-performance and low-power consumption SoC chip, integrates a simulation front end, an electric energy measurement module, an enhanced 8052 core, an RTC, a WDT, a Flash, an SRAM, an LCD driver, and other functional modules, and is a three-phase multifunctional electric energy monitoring single-chip solution with higher cost performance.

V9911 supports 3.3V or 5V mains operated, wide voltage input range: 2.5V-5.5V, and adopts low power consumption design to support flexible electricity larceny prevention application. With 4 independent oversampling sigma/delta ADC: 1 path of voltage, 2 paths of current and 1 path of multifunctional measuring channel. The V9911 metering accuracy meets the requirements of GB/T17215.321-2008, GB/T17215.322-2008 and GB/T17215.323-2008.

In the dynamic range of 5000:1 of current, the active metering error is less than 0.1 percent;

in the dynamic range of 3000:1 of current, the reactive power metering error is less than 0.1 percent;

in the dynamic range of 1000:1 of current, the effective value measurement error of voltage/current is less than 0.5 percent;

the V9911 chip can provide various data as follows:

A. original waveform and direct current component of voltage/current signal;

B. voltage/current signal waveform caching;

C. instantaneous/second average active/reactive power and second average apparent power;

D. instantaneous/second average voltage/current effective value;

E. forward and reverse active/reactive power;

F. line voltage frequency;

G. temperature, measurement accuracy +/-1 ℃;

H. battery voltage/external voltage.

Specifically, the three-phase electric energy measurement module 102 is configured to sample an ac current value and an ac voltage value measured by the micro current transformer 105 and the micro voltage transformer 106, perform electric energy calculation, store electric energy parameters, the three-phase electric energy measurement module 102 employs a V9203 three-phase metering chip, and the three-phase electric energy measurement module 102 and the single chip 101 perform data exchange with an SPI communication interface.

In this embodiment, the measurement module is a key part of the electric energy measurement terminal, and is mainly used for calculating electric energy of sampling current and voltage, storing electric energy parameters, and exchanging data between the measurement chip and the CPU through an SPI communication interface;

the metering chip is V9203, and the chip is a high-precision, wide-range and low-power consumption three-phase metering chip aiming at the national network/south network market and promoted by Hangzhou Wangao. The chip meets the requirements of GB/T17215.321-2008, GB/T17215.322-2008, GB/T17215.323-2008 and GB/T17215.324-2016. In a dynamic range of 10000:1, the full wave/fundamental wave has a functional amount and a metering error of less than 0.1 percent; in a dynamic range of 5000:1, the full wave/fundamental wave reactive energy metering error is less than 0.1 percent;

the chip supports 7 paths of original voltage/current signal waveforms (22-bit), the DMA mode outputs and the updating frequency is 6.4 kHz. The direct current component of 7 paths of voltage/current signals can be measured; the full wave/fundamental wave voltage/current effective value and active/reactive/apparent power/energy of the combined phase and each phase; the effective value of zero line current; frequency/phase/power factor, providing a plurality of operating modes, in addition to the normal operating mode, supporting: in the power failure full-voltage loss pre-judging mode, a judging threshold value can be set, the typical working current of the chip is 1.65mA, and the response time is less than 20 ms; in the current effective value measuring mode, the typical working current of the chip is 5.1mA, and the response time is less than 135 ms; the circuit diagram of the metering part designed by V9203 is shown in figures 3 and 4.

Specifically, the communication module 103 completes RS-485 communication by using a V6602 chip.

In this embodiment, the device uses a V6602 chip to complete RS-485 communication; v6602 is a transceiver with very low power consumption, has + -15 KVESD protection, and is an RS-485 transceiver completely in accordance with EIA/TIA-485 standard requirements. V6602 includes a transmitter and a receiver, which have high drive capabilities, allowing 256 transceivers to be connected in parallel on the same communication bus.

The V6602 is internally provided with a low slew rate driver, so that EMI and reflection caused by improper terminal matching can be reduced, error-free data transmission of 500kbps at most can be realized, the requirements of industrial Internet projects can be well met, and the structure is shown in figure 5.

V6602 has circuit failure protection function; v6602 ensures that the Receiver Output (RO) is logic high when the receiver input is short or open, or when all drivers attached to the terminal matched transmission line are disabled; v6602 receiver input threshold values are-10 mV and-55 mV, RO is a logic high if the receiver differential input voltage (A-B) is greater than-10 mV; if the receiver differential input voltage (A-B) is less than-55 mV, then RO is a logic low level. When all drivers on the terminal matching transmission line are in the disabled state, the differential input voltage of the receiver is pulled down to 0V, and RO should be logic high according to the input threshold of the receiver.

V6602 contains an overheat shutdown circuit to protect the device from over-temperature, preventing excessive power consumption when the device fails. When the temperature of the chip exceeds 150 ℃, the chip enters an overheating shutdown mode. V6602 contains an overvoltage protection circuit that works all the time when the chip is in transmit state, automatically comparing the output voltage across A, B: when VA or VB is smaller than GND or is larger than Vcc, the chip enters an output circuit overvoltage protection mode.

The input impedance of a standard RS-485 receiver is 12k omega (1 unit load), and a standard driver can drive 32 unit loads at most. V6602 has a load impedance greater than 1/8 units (R1>96k Ω), allowing 256 transceivers to be connected in parallel on the same communication bus. These devices can be combined arbitrarily, and can be hung on the same bus as long as the total load does not exceed 32 unit loads, as shown in fig. 6.

Specifically, the LORA module 104 uses an LORA spread spectrum communication chip SX1278 of the SEMTECH to implement the wireless data transmission function of the device.

In the embodiment, the device uses an LORA spread spectrum communication chip SX1278 of the SEMTECH to realize the wireless data transmission function of the device; the SX1278 is used for ultra-long distance spread spectrum communication, has strong anti-interference capability, and the LORA modulation technology has obvious advantages in the aspects of anti-blocking and selectivity, thereby solving the problem that the traditional design scheme can not give consideration to distance, anti-interference and power consumption. The maximum link budget of the SX1278 can reach 168dB, and the constant radio frequency power output is realized when the voltage of +20dBm-100mW changes, and the working circuit is shown in the figure 7 and the figure 8.

Specifically, the model of the micro current transformer 105 is CT 128B; miniature voltage transformer 106 is model number TV 1005M.

In the embodiment, the device detects the alternating voltage and the alternating current value through the alternating voltage and current transformer module, and is responsible for whether to cut off through the 5V relay circuit, and whether the condition of cutting off is that whether the instantaneous power exceeds 200W is judged. Miniature voltage transformer 106 is model number TV1005M and miniature current transformer 105 is CT 128B. The alternating voltage detection is to convert 220V alternating current into 0-5V low-voltage direct current through a voltage transformer, and obtain digital quantity after the A/D conversion of V9911. The model of the designed voltage transformer is selected from TV1005M, and the basic structure of the voltage transformer is a transformer with iron cores, which mainly comprises a primary coil, a secondary coil, the iron cores and insulating materials. The electromagnetic induction principle is the working principle of a voltage transformer, the working principle of a current transformer is also the electromagnetic induction principle, but the structures of the two principles are far away. The current transformer can convert the current into direct current voltage of 0-5V, the V9911 is subjected to A/D conversion to obtain digital quantity, and the actual alternating current is obtained after calculation. The rated input maximum current of the miniature precision current transformer CT128B is 10A, if the monitoring of larger current is needed, an external current transformer can be used, an open type current transformer is suggested to be used, and the construction is convenient.

Specifically, the power management module 107 is composed of AS1117-5 and AS1117-3.3 chips, and outputs 3.3V and 5V dc voltages to provide operating power for the chips in the wireless power metering terminal system.

In this embodiment, the power management module 107 is mainly used to provide working power for the single chip 101, the metering chip of the three-phase electric energy measurement module 102, the communication module 103, and the LORA module 104, and is composed of AS1117-5 and AS1117-3.3 chips, and outputs 3.3V and 5V dc voltages to provide working power for the chips in the electric meter system, although many chips are wide voltage adaptive, the two paths of dc power supply separately supply power, which improves the working reliability and safety of the power supply system.

The AS1117 is a forward low-voltage drop voltage stabilizer, the voltage drop is 1.2V under the current of 1A, the fixed output voltage version of the forward low-voltage drop voltage stabilizer can output common voltages of 1.5V, 2.5V, 3.3V, 5.0V and the like, and the accuracy is 1%. The chip is internally provided with an overheating protection and current limiting circuit, can seamlessly replace LM1117, and has an operating circuit shown in figure 9.

Specifically, the wireless power metering terminal further comprises a ferroelectric memory FM24C64B, a crystal oscillator and a key, wherein the ferroelectric memory FM24C64B is electrically connected with the single chip microcomputer 101.

In this embodiment, the wireless power metering terminal further includes an antenna disposed on the terminal body 100, and the antenna preferably uses an SMA interface and a sucker antenna with a gain of 5dBi or more, and may also use an SMA interface and a rubber rod antenna with a gain of 5dBi or more.

The working principle and the using process of the invention are as follows: the guide tracked multi-functional wireless electric energy of three-phase measurement terminal uses V9911 as main control chip, and high accuracy three-phase electric energy measurement chip V9203 is as measuring the chip, detects alternating voltage and alternating current value respectively through voltage transformer TV1005-M and current transformer CT128B, and the numerical value that its was gathered can show on the LCD screen and also can pass to the host computer on the RS485/LORA interface.

The three-phase guide rail type multifunctional wireless electric energy metering terminal is mainly used for metering three-phase active electric energy of a low-voltage network and sending data to a communication server in a wireless mode; the terminal can measure positive and reverse active electric energy, input and output reactive electric energy, can measure A, B, C three-phase voltage, three-phase current, each phase and total active power, reactive power, power factor and power grid frequency, and has the function of recording the maximum demand; accumulating and storing the electric energy according to the existing and the idle work and the total, the peak, the flat and the valley of the positive direction and the reverse direction respectively; the electric energy data freezing function is provided (the default freezing time is 24 hours at the end of each month), and 12 months of freezing data can be stored in the table; all stored data are not lost after power failure and can be kept for more than 10 years.

This terminal has configured the LCD display screen, can carry out the clock, rate period isoparametric sets, electric energy pulse output function has, support RS485 communication and LORA wireless communication function, can convenience of customers carries out the power consumption monitoring management, it is high to have a precision, and is small, advantages such as simple to operate, support DIN35 standard guide rail, can install in all kinds of block terminals in a flexible way (metal block terminal need with the sucking disc antenna as far as outside the block terminal), realize the branch electric energy measurement to different regions and different loads fast, statistics and analysis.

The user can set up equipment internal parameters according to on-the-spot actual conditions, but wide application in fields such as all kinds of enterprises, house, intelligent building, collection trade market and dormitory, school, especially all kinds of power consumption monitoring fields.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a multi-functional wireless electric energy measurement terminal of three-phase guide tracked, includes terminal body (100), the inside of terminal body (100) is equipped with singlechip (101), three-phase electric energy measurement module (102), communication module (103), LORA module (104), miniature current transformer (105), miniature voltage transformer (106) and power management module (107), its characterized in that: miniature current transformer (105) and miniature voltage transformer (106) are connected with three-phase electric energy measurement module (102) respectively, miniature current transformer (105) and miniature voltage transformer (106) are used for measuring alternating current value and alternating current voltage value respectively, three-phase electric energy measurement module (102), communication module (103) and LORA module (104) are connected with singlechip (101) respectively, three-phase alternating current is connected in power management module (107), power management module (107) are used for providing working power supply to singlechip (101), three-phase electric energy measurement module (102), communication module (103) and LORA module (104).

2. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: the single chip microcomputer (101) adopts a V9911 electric energy metering SOC chip.

3. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: the three-phase electric energy measurement module (102) is used for sampling alternating current values and alternating voltage values measured by the micro current transformer (105) and the micro voltage transformer (106), calculating electric energy, storing electric energy parameters, adopting a V9203 three-phase metering chip for the three-phase electric energy measurement module (102), and exchanging data between the three-phase electric energy measurement module (102) and the single chip microcomputer (101) through an SPI communication interface.

4. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: and the communication module (103) adopts a V6602 chip to complete RS-485 communication.

5. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: the LORA module (104) adopts an LORA spread spectrum communication chip SX1278 of SEMTECH for realizing the wireless data transmission function of the equipment.

6. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: the miniature current transformer (105) is CT 128B.

7. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: the miniature voltage transformer (106) is of the type TV 1005M.

8. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: the power management module (107) is composed of AS1117-5 chips and AS1117-3.3 chips, and outputs 3.3V and 5V direct-current voltages to provide working power for the chips in the wireless electric energy metering terminal system.

9. The three-phase guide rail type multifunctional wireless electric energy metering terminal according to claim 1, characterized in that: the wireless electric energy metering terminal also comprises a ferroelectric memory FM24C64B, a crystal oscillator and a key which are electrically connected with the single chip microcomputer (101).