CN202649307U

CN202649307U - Embedded electric energy meter based on Ethernet

Info

Publication number: CN202649307U
Application number: CN 201220312365
Authority: CN
Inventors: 徐斌; 古雄文; 刘岩
Original assignee: ZHUHAI PILOT TECHNOLOGY Co Ltd
Current assignee: ZHUHAI PILOT TECHNOLOGY Co Ltd
Priority date: 2012-07-01
Filing date: 2012-07-01
Publication date: 2013-01-02
Anticipated expiration: 2022-07-01

Abstract

An embedded electric energy meter based on the Ethernet comprises a data acquisition module, a control module, an Ethernet communication module, an operation power supply, a data RAM and a display circuit, wherein the data acquisition module comprises an electric-energy metering chip, a current sampling circuit and a voltage sampling circuit. The current sampling circuit and the voltage sampling circuit are respectively connected with a current input channel and a voltage input channel of the electric-energy metering chip. The electric-energy metering chip is connected with the control module by an SPI bus. The control module is connected with the data RAM and the display circuit. The Ethernet communication module comprises an Ethernet controller, a network transformer and an RJ45 interface successively connected with each other. The control module is connected with the Ethernet controller by the SPI bus. The operation power supply respectively provides for the electric-energy metering chip, the control module and the Ethernet controller. A requirement of power use management is raised, so that the electric energy meter has the advantages of high precision, low power consumption and small harmonic wave influence finally. The electric energy meter can realize functions of remote control and automatic meter reading.

Description

Embedded electric energy meter based on Ethernet

Technical field

The utility model relates to a kind of embedded electric energy meter, relates in particular to a kind of embedded electric energy meter based on Ethernet.

Background technology

Electric energy plays very important effect in modern society, and industry-by-industry and the people's daily life all be unable to do without it.Therefore, electric energy also comes into the market with regard to becoming a kind of special commodity, the problem that the electric energy that how user is consumed measures accurately accounting and must face with regard to becoming us control and the management of electric energy.In this case, electric energy meter has arisen at the historic moment.Current electric energy meter is as the gauging instrument of weighing the electric energy usage quantity, its technical requirement is very high, not only require accurately with stable, and must guarantee reliably and with long-term hanging net operation, along with the progressively foundation of China's electricity market and perfect, received increasing concern as the electric energy meter of electric system important component part.Just being widely used in the middle of the residential building residential quarter such as single-phase electric energy meter, is a kind of the simplest electric energy meter.Had after the metering ammeter, the electric weight that how ammeter is measured is sent to power department becomes again another problem that we must face.Traditional operating mode all is to rely on manual metering, inefficiency not only, and produce easily error, and at the beginning of using, also have various problems such as construction, wiring.

The utility model content

The purpose of this utility model has been to provide a kind of embedded electric energy meter based on Ethernet, comprises data acquisition module, control module, ethernet communication module, working power, data RAM, display circuit.Data acquisition module comprises electric energy computation chip, current sampling circuit and voltage sampling circuit, and current sampling circuit and voltage sampling circuit link to each other with the voltage input channel with the electric current input channel of electric energy computation chip respectively; Electric energy computation chip links to each other with control module by spi bus; Be connected with data RAM and display circuit on the control module; The ethernet communication module comprises ethernet controller, network transformer, RJ45 interface, and they are sequentially continuous; Control module links to each other with ethernet controller by spi bus; Working power is given respectively electric energy computation chip, control module and ethernet controller power supply.

Electric energy computation chip adopts the ADE7758 electric energy computation chip; Control module adopts single-chip microcomputer MC68HC11A8; Ethernet controller adopts ethernet controller ENC28J60.

Embedded electric energy meter based on Ethernet of the present utility model has improved management of power use requirement, makes ammeter finally reach precision height, low in energy consumption, the advantage such as influence from harmonic is little, can realize the functions such as Long-distance Control, automatic data logging again.

Description of drawings

Fig. 1 is based on the structure principle chart of the embedded electric energy meter of Ethernet;

Fig. 2 is current sampling circuit figure;

Fig. 3 is voltage sampling circuit figure.

Embodiment

Embedded electric energy meter based on Ethernet of the present utility model comprises data acquisition module 1, control module 2, ethernet communication module 3, working power 4, data RAM 5, display circuit 6.

Fig. 1 is based on the structure principle chart of the embedded electric energy meter of Ethernet.Wherein data acquisition module 1 comprises electric energy computation chip 11, current sampling circuit 12 and voltage sampling circuit 13.The electric energy computation chip 11 preferred ADE7758 electric energy computation chips that adopt, this chip are to use chip by a high precision three phase electrical dress of ADI's exploitation, have three voltage input channels and three electric current input channels.Current sampling circuit 12 and voltage sampling circuit 13 link to each other with the voltage input channel with the electric current input channel of electric energy computation chip 11.

Current sampling circuit 12 and voltage sampling circuit 13 are respectively shown in Fig. 2,3.The selection of current sampling resistor and divider resistance size should take full advantage of the A/D conversion figure place of electric energy computation chip ADE7758, in order to improve the precision of measuring, is unlikely to make in the time of also will preventing overrange simultaneously to measure and overflows.Because the difference input voltage of electric energy computation chip APE7758 is lower than 0.5 V, so electric current and first effect of voltage sample passage will be input to the limiting voltage of chip exactly below 0.5V.In the circuit simple RC network play a part anti-aliasing, take A mutually as example, among Fig. 2, R1, R2, R7, R8, C1, C2 consists of the anti-aliasing filter network of input terminal.Frequency alias is the endemism during digital sample is processed, and when sample frequency will produce aliasing during less than the signal highest frequency of twice, consequent alias will have a strong impact on measurement result.Because electric energy computation chip ADE7758 chip has higher sample frequency, and the cutoff frequency of designed LPF wave filter is far below it, like this can attenuates high frequency signals, thus effectively stop the generation of aliasing.Among Fig. 3, R20, R21, R22, R15 consists of the attenuation network of A phase voltage passage.

Get back to Fig. 1, electric energy computation chip 11 links to each other with control module 2 by serial peripheral equipment (SPI) bus, is connected with data RAM 5 and display circuit 6 on the control module 2.The control module 2 preferred single-chip microcomputer MC68HC11A8 that adopt, this single-chip microcomputer is the High Performance SCM of motorola inc's exploitation.

Ethernet communication module 3 comprises ethernet controller 31, network transformer 32, RJ45 interface 33, and they are sequentially continuous.Control module 2 links to each other with ethernet controller 31 by serial peripheral equipment (SPI) bus.The ethernet controller 31 preferred ethernet controller ENC28J60 that adopt the production of Microchip Technology company.

Working power 4 is given respectively electric energy computation chip 11, control module 2 and ethernet controller 31 power supplies.

The most important function of electric energy metered system is accurately to measure various electrical energy parameters, such as voltage, electric current, active power, reactive power, frequency, power factor, and under-voltage and disconnected mutually detection, frequency analysis etc.At present metering system mainly contains two kinds: a kind of is to adopt the special measurement chip, and its data that detect are processed, and obtains wanting the parameter of measuring; Another kind is directly electric current, voltage to be sampled, and by calculating electrical energy parameter.For measuring accuracy and the reliability that improves system, native system adopts special-purpose electric energy computation chip ADE7758 to come sampled signal, is equipped with single-chip microcomputer MC68HC11A8 programming and realizes several functions.Sampling section is by current transformer, voltage transformer (VT) and peripheral processes the electric circuit constitute, thereby obtains the real time datas such as electric current, voltage, frequency, phase place, and is input in the computation chip.

Computation chip obtains various electrical energy parameters with metering and is input in the main control singlechip by to after the metering of each input signal, is determined desired parameters delivered in the storer after treatment by its to store, and delivers to the display part and show.Communication interface adopts ethernet controller ENC28J60 and host computer to communicate.If communication interface is received the order of host computer, then with command transfer in single-chip microcomputer, electrical energy parameter can be sent to host computer according to order, can manage concentratedly electric energy, realize the functions such as automatic data logging, Long-distance Control.

Claims

1. embedded electric energy meter based on Ethernet, comprise data acquisition module (1), control module (2), ethernet communication module (3), working power (4), data RAM (5), display circuit (6), it is characterized in that data acquisition module (1) comprises electric energy computation chip (11), current sampling circuit (12) and voltage sampling circuit (13), current sampling circuit (12) and voltage sampling circuit (13) link to each other with the voltage input channel with the electric current input channel of electric energy computation chip (11) respectively; Electric energy computation chip (11) links to each other with control module (2) by spi bus; Be connected with data RAM (5) and display circuit (6) on the control module (2); Ethernet communication module (3) comprises ethernet controller (31), network transformer (32) and the RJ45 interface (33) that order links to each other; Control module (2) links to each other with ethernet controller (31) by spi bus; Working power (4) is given respectively electric energy computation chip (11), control module (2) and ethernet controller (31) power supply.

2. a kind of embedded electric energy meter based on Ethernet according to claim 1 is characterized in that electric energy computation chip (11) adopts the ADE7758 electric energy computation chip.

3. a kind of embedded electric energy meter based on Ethernet according to claim 1 is characterized in that control module (2) adopts single-chip microcomputer MC68HC11A8.

4. a kind of embedded electric energy meter based on Ethernet according to claim 1 is characterized in that ethernet controller (31) adopts ethernet controller ENC28J60.