CN203012013U - ARM-based multi-user intelligent electric meter - Google Patents

Abstract

The utility model discloses an ARM-based multi-user intelligent electric meter, comprising a software system and hardware, wherein the software system consists of an operating system, an underlying driver and application software, and the operating system adopts an Microc/OS II embedded type real-time multitask operating system; and the electric meter is composed of a main control board, a communication board, a display board, a relay control board and a power supply board, and a power supply circuit adopts a transformer for step-down power supply. The ARM-based multi-user intelligent electric meter overcomes the defects of the prior art, adopts an LPC2294 as the core, realizes the metering and data transmission of grid voltage, current, electric energy and other parameters, and can manage the electricity consumption of the users through networking with the UnionPay.

Description

Based on the ARM user intelligent

Technical field

The utility model relates to the intelligent electric meter technical field, specifically belongs to the user intelligent based on ARM.

Background technology

Along with the development of city dweller's house, building constantly increases with the table demand, and traditional metering method that a plurality of electric energy meters are hung over is together more and more showed its drawback; Be that volume is large, cost is high, and construction costs is high, is unfavorable for the concentrated management of power use of novel house.Multi-user, multifunctional intellectual ammeter can not only address the above problem well, can also realize a lot of intelligentized functions.

The utility model content

The purpose of this utility model is to provide the user intelligent based on ARM, the deficiencies in the prior art have been overcome, this table LPC2294 is core, realized line voltage, electric current, the isoparametric metering of electric energy and data transmission, and can with the network management user's of Unionpay power consumption.

The technical solution adopted in the utility model is as follows:

Based on the ARM user intelligent, comprise software systems and hardware, software systems are comprised of operating system, bottom layer driving and application software, operating system adopts the Microc/OS-II embedded real-time multi-task operating system, described electric energy meter is comprised of master control borad, communication board, display board, Control plate and power panel, and power circuit adopts the transformer pressure-reducing power supply.

Described master control borad is by power circuit, the A/D front end circuit, and data acquisition circuit, the host CPU circuit, E2PROM circuit and electronic circuit thereof form.

Described display board adopts RS-485 serial line interface and master control borad swap data.

Described communication board comprises modular converter, ethernet interface module, serial interface module, the parallel interface module of CAN to 232.

Described power panel comprises that the input of 38～180V direct current, input filter, AC/DC conversion, over-current over-voltage protection, output filter, rear class mu balanced circuit form.

Compared with the prior art, the beneficial effects of the utility model are as follows:

The utility model intelligent electric energy meter can measure 48 family residents' power consumption simultaneously.This electric energy meter adopts 2 LPC2294 (ARM) to control, with communication and the collection of completing data; Adopt 2 ARM, with offloading the CPU, improve multifunction and the intellectuality of system.With respect to alone family ammeter, New multiple-user meter has nearly 32 the tunnel with upper channel, adopts same system to carry out time-division processing, and this system adopts 12 A/D conversion chip AD8364, can guarantee precision and the speed of data acquisition.

Description of drawings

Fig. 1 is the structured flowchart of the utility model electric energy meter;

Fig. 2 is the utility model power circuit principle block diagram;

Fig. 3 the utility model A/D front end circuit theory diagram;

Fig. 4 the utility model power panel theory diagram;

Fig. 5 the utility model input filter circuit;

Fig. 6 the utility model software architecture diagram;

Fig. 7 the utility model collection section process flow diagram;

Fig. 8 the utility model Department of Communication Force process flow diagram;

Embodiment

Referring to accompanying drawing, based on the ARM user intelligent, the hardware and software of this electric meter system adopts modularization, standardized designs and takes into full account the extended capability of system.Electric energy meter is comprised of master control borad, communication board, display board, Control plate and power panel 5 parts.Communication module is responsible for telecommunication; Master control borad is completed all basic functions of electric energy meter; Display board is as the display terminal of system; The Control plate is completed outage and power supply control; Power panel provides the electric current of stability and safety for whole system.

The principle of work of this electric energy meter is: at first by No. 32 current transformers samplings, then send into AD8364 by amplification filtering after the analog switch gating and be converted into digital quantity, the voltage of voltage transformer (VT) sampling is simultaneously sent into A/D converter through filtering.The digital quantity that obtains voltage and current is given to collection CPU.Gather CPU and calculate instantaneous power according to instantaneous voltage and momentary current, and result is delivered to display module stored.Gather CPU and transmit data with the CAN that communicates by letter, communication cpu arrives host computer by the CAN bus transfer.

Master control borad carries out 32 road acquisition times to current and voltage signals.The data that collect are carried out data process, obtain active power, reactive power, and make precision reach 0.1 grade standard.Master control borad is also completed the exchanges data with communication board and relay board.Can security monitoring, error message is provided, go out error protection and recovery.Master control borad is by power circuit, the A/D front end circuit, and data acquisition circuit, the host CPU circuit, the electronic circuits such as E2PROM circuit form.

Power circuit adopts conventional transformer pressure-reducing power supply.At the transformer input end, carry out pre-service at the electric network source to input, as overvoltage protection, overcurrent protection, filtering.Power circuit is the whole system power supply, and it has fundamentally determined stability and the security of system works, is system: the pith of EMC design.Power circuit can filtering the interference of external electrical network, can also prevent that internal interference from altering people's electrical network simultaneously.Various defencive functions are provided, comprise overcurrent protection, output short circuit protection, output overloading protection etc.For communication board, master control borad, Control plate and display board provide stable, sufficient power supply supply.When line voltage changes within the specific limits, guarantee the basicly stable of builtin voltage.

The A/D front end circuit is responsible for each road current/voltage sensor passage of timesharing gating, and signal is amplified and filtering is processed, then the A/D circuit of sending into the back carries out data acquisition.Realize that with operational amplifier signal amplifies and completes active power filtering.MUX is equivalent to multi-channel electronic switch, and with 8 passage A/D chip CD4051, its resistance is little, is with roomyly, and loss is little, connects resistance less than 100Q.

Electric current and voltage sensor form by mutual inductor, all are converted to voltage signal output after resistance sampling.For preventing causing the late-class circuit fault because sensor damages, sensor signal has been carried out conservation treatment.32 road current sampling signals are divided into 3 groups, the A phase of the corresponding three-phase electricity of difference, the B phase, with C mutually, the three-phase voltage sampled signal is corresponding with the tertiary current sampled signal, carry out the timesharing gating by data selector, to guarantee arbitrary sampling instant gating three-phase current sampled signal and corresponding voltage sampling signal simultaneously.Generally all fainter from the signal of sensor output, be not suitable for carrying out data acquisition, adopt operational amplifier to amplify, simultaneously, in order to prevent other interference, also to carry out filtering and process.Reached from the signal of this one-level output the requirement that signal is processed, just carried out the A/D conversion.

Data acquisition is completed by AD8364, high-performance A/D converter (ADC) chip of 6 Channel Synchronous sample conversion, list+5V power supply, 16 high speed parallel interfaces, and chip belt 2.5V reference voltage source can be used as the reference voltage of ADS8364.Every ADS8364 is the ADC formation of 250kb/s (when external clock is 5MIIz) by 3 switching rates, each ADC has 2 analog input channels, each passage has sampling holder, 3 ADC form 2 couples of simulation input ends, can be simultaneously to 1～2 pair of input signal wherein sample simultaneously maintenance, then conversion one by one.Because 6 passages can be sampled simultaneously, 6 groups of analog quantitys that obtained by electric current and voltage sample in system gather simultaneously.3 are used for gathering the magnitude of current, and another 3 are used for gathering voltage.

Require communication distance be tens meters on during km, extensively adopt RS 485 serial bus standards.RS485 adopts balance to send and differential received, therefore has the ability that suppresses common mode interference.Signal transmission adds that bus transceiver has high sensitivity, can detect the voltage that is low to moderate 200mV, therefore can be restored beyond km.RS 485 adopts half-duplex operation, whenever can only have any to be in the transmission state, so transtation mission circuit must be controlled by enable signal.Very convenient when RS 485 is used for multi-point interconnection, can save many signal wires.Use the RS 485 formation distributed system of can networking, it allows 32 drivers at most in parallel and 32 receivers.

Display board LED shows friendly interface, comprehensive display user's information, employing 485 and master control borad swap data.The liquid crystal display of this system is 10.4 inches, and resolution is 640 * 480,260,000 looks.Drive and adopt design liquid crystal control circuit in FPGA.This system adopts the demonstration of Avalon LCDController to control the IP module, takies the LE of 6000 left and right, can realize very abundant function.

Communication board is completed the protocol conversion of CAN to 232, the correct interpretive order of energy and data, and have mistake and error correction.Communication board should comprise following communication function module, i.e. the modular converter of CAN to 232, ethernet interface module, serial interface module, parallel interface module.

Because the work power consumption of whole screen display is the 50W left and right, therefore need to adopt the higher Switching Power Supply of efficient.The efficient of this Power Management Design scheme reaches 87%.

The power panel theory diagram is seen Fig. 4, and it is comprised of the input of 38～180V direct current, input filter, AC/DC conversion, over-current over-voltage protection, output filter, rear class mu balanced circuit.

The input filter circuit is seen Fig. 5.Seal in a relay in input circuit, can realize and supervising device synchro switch machine.V19 is anti-lightning strike diode; V2 is a rectifier bridge, connects inverse time when the power lead of input is positive and negative, and this power supply can work.

Operating system adopts the Microc/OS-II embedded real-time multi-task operating system.The Microc/OS-II embedded real-time multi-task operating system be one based on the real-time multi-task kernel of preemptive type, curable, can cut out, have high stability and reliability.In addition, the distinguishing feature of Microc/OS-II is exactly that source code is open, is convenient to transplant and safeguard.Bsp driver mainly comprises the FPGA hardware components, as display driver, A/D conversion driving, digital I/O driving, serial communication driving, 485 bus driver, 422 bus driver, CAN bus driver, USB drives, Ethernet interface driving, the driving of Ic card interface, voice output driving, sdram interface driving, FLASH interface driver etc.

Application software refers to information acquisition, processing, output, the display routine worked out for the specific function that realizes system.The exploitation of this part software is the main contents of software work.Application software is carried out the program structure design according to structuring, modularization, unitized principle of design, whole program is divided into several large modules from structure: data input processing module, event capturing module, event processing module, data memory module, they are mainly generated when the initialization by master routine, finish when withdrawing from system.Can be divided into more tiny module according to function under 4 modules, to such an extent as to realize subroutine and the function of simple function, input processing module mainly is responsible for the data of outside are connected with signal with the data of external unit being connected; The event capturing module mainly monitors, identifies and report the generation of each external event, with the form notice primary control program of message, activates the respective process in event processing module, the response external event afterwards.This module requires high reliability, high real-time, and guarantees not lose any external event; Event processing module is the main body that software function realizes, it is comprised of many loose couplings functional module together, externally carries out specific flow process under the triggering of event, realizes certain function; Data memory module is mainly used in storing some important service datas, on the one hand as ex-post analysis, the more important thing is some useful data of storage, after system restart, can guarantee that active data is unlikely to lose like this.For this complicated system, need to coordinate to complete the work of each side, adopts 2 ARM, to realize the control of this system, coordinate respectively to complete and communicate by letter and the work of collection aspect.

The capture program process flow diagram as shown in Figure 7.The initialization of capture program completion system with to current-voltage sampling, communicate by letter, the calling of the subroutine such as demonstration.Begin to start shooting and follow inspection, need to judge whether overcurrent of system after collection, when outage occurs when, the demonstration of cutting off the power supply.

Believe program flow diagram as shown in Figure 8, communications portion will be processed data and the handling interrupt of collection.The communications portion software flow is as follows:

(1) communications portion CPU starts shooting and follows inspection and judged whether system mistake, if wrong alarm indication;

(2) do not have mistake to wait for interruption, the judgement interrupt type of having no progeny during electric energy meter is received is that sampling is interrupted, or communication disruption, if image data is interrupted, sends and receives the image data answer signal;

(3) electric energy meter after receiving image data compares these data and user power utilization, judges whether arrearage, if power-off signal is sent in arrearage, and send demonstration, otherwise sends the read data order, the storage data;

(4) during communication disruption, may be the pre-payment of wanting inquiring user, when wanting inquiring user, begin to read external memory storage, afterwards result be sent to host computer, when wanting pre-payment, send to send the external memory storage order;

(5) have no progeny in completing to forward to and wait for next interruption, circulation said process.

Claims (5)

1. based on the ARM user intelligent, comprise software systems and hardware, software systems are comprised of operating system, bottom layer driving and application software, operating system adopts the Microc/OS-II embedded real-time multi-task operating system, it is characterized in that: described electric energy meter is comprised of master control borad, communication board, display board, Control plate and power panel, and power circuit adopts the transformer pressure-reducing power supply.

2. according to claim 1 based on the ARM user intelligent, it is characterized in that: described master control borad is by power circuit, the A/D front end circuit, and data acquisition circuit, the host CPU circuit, E2PROM circuit and electronic circuit thereof form.

3. according to claim 1 based on the ARM user intelligent, it is characterized in that: described display board adopts RS-485 serial line interface and master control borad swap data.

4. according to claim 1 based on the ARM user intelligent, it is characterized in that: described communication board comprises modular converter, ethernet interface module, serial interface module, the parallel interface module of CAN to 232.

5. according to claim 1 based on the ARM user intelligent, it is characterized in that: described power panel comprises that the input of 38～180V direct current, input filter, AC/DC conversion, over-current over-voltage protection, output filter, rear class mu balanced circuit form.

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