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LOW COST ELECTRICITY METER READING SYSTEM

USING GSM

PRESENTED BY

JEFF JOSEPH

ROLL NO:26

S7,EEE

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Preview

Introduction Existing system It’s Disadvantages Requirement of proposed system Hardware Implementation Software Implementation Results Advantages Conclusion References

Introduction

Total electricity demand in India 2015-2016 is 1,162,423 MU but available is 1,138,346 MU

Metering-one of the most imp. steps in transmission and usage of electricity.

Most of the meters are of digital meters working with human interventions

The proposed system-working of energy meter without human interventions, less power consumption

GSM module-for communication & microcontroller MSP430FG4618

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Two types of energy meters are commonly used Mechanical energy meter & Electronic energy meter

Existing system

Existing system (Cont...)

Mechanical energy meter work - principle of electromagnetic induction, metallic disc acted upon- two coils

Primary and secondary coils produce magnetic flux in proportional to voltage and current respectively

Field due to voltage-lagg by 90 degree results eddy current, exert a force on the disc

Disc attached to a spindle-worm gear registers This drives the register where the readings are noted

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Existing system (Cont...)

In electronic meter, current measure-current transformer and voltage-resistive voltage divides

An ADC converts these values into digital and it is given to microprocessor

Hence this calculate the energy consumption It has EEPROM employed for storing values over a 20

years of detection

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It’s Disadvantages

High labour cost Improper & Untimely billing Consumes high amount of power Loss of unaccountable energy & paperwork's Prone to power theft Cause high travel expenses and time consumption for

non reachable rural areas meter reading

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Proposed system overview

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The urgent need is a low cost system that is available at a very low rate with accurate reading

The current and potential transformers are used to attenuates current and voltage respectively

This reduced values are conditioned using different elements to be compactable with the inbuilt ADC

The digital values are then processed by microcontroller hence the power consumption is calculated.

This microcontroller is connected to GSM module

Proposed system overview (Cont…)

GSM modules sends information to users and suppliers via SMS

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Hardware Implementation

Current Transformer Current transformer produces a reduced current

accurately proportional to the current in the circuit, which can be conveniently connected to measuring and recording instruments.

Potential Transformer Potential transformer or voltage transformer gets used

in electrical power system for stepping down the system voltage to a safe value which can be fed to low ratings meters and relays.

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Hardware Implementation (Cont…)

Signal conditioning module It contains three elements Precision rectifier Ripple eliminator Voltage divider

Rectify the ac voltage-smooth dc voltage, reduced intensity compactable with microcontroller. These are mainly done with capacitor circuits

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Hardware Implementation (Cont...)

MicrocontrollerHere we use MSP430FG4618,Its specifications are• 80 I/O pins• Low supply voltage Range-1.8v to 3.6v• Ultra low power consumption(Active mode-400 μA)• 16bit RISC Architecture• 12-Bit A/D Converter• one universal synchronous/asynchronous

communication interface

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Hardware Implementation (Cont….)

• Integrated LCD Driver up to 160 Segments

Its computations• Power consumption is computed every second• Summing power consumption over a given period of

time gives energy used by a consumer13

Hardware Implementation (Cont...)

Its computations• 1 kWh = 1 kW*1 hr = 1 kJ/s*3600s = 3600000 J• when the sum reaches 3600000, energy equivalent to

1 kW/hr or simply 1 unit is consumed• Real Time Clock(RTC) interrupts the controller every

second• RTC keeps track of date and time enabling the meter

console to send SMS at user configurable intervals.

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Hardware Implementation (Cont...)

GSM module• SIMCON sim900a GSM module is interfaced to the

microcontroller• The on chip UART communicates the usage

information to the GSM module• SMS is generated after regular interval of time which

can be sent to the local database for further processing of the billing

• The database contains information like customer identification number, meter no and no of unit consumed

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Software Implementation

AT commands of sim900a are used for establishing communication and conveying the usage information

• AT-initialise GSM module• AT+HVOIC-end all existing calls• AT+CMGF-set message format to text mode• AT+CMGS-followed by the destination number is used

to convey the same to the GSM module UART transmission is carried out at a baud rate of

9600

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Results The power measured by the meter in testing phase for load

drawing up to 20A at 230V AC: When a graph is plotted on ACTUAL POWER V/S CALCULATED

POWER

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Results (Cont....)

The readings plotted using MATLAB give a fairly linear graph with an average error of 0.18%

The maximum consumption of the system is 2W/months

total cost of the unit including electronic components, controller, GSM module, and current and voltage sensors adds upto INR 1800 (less than $35)

SMS containing usage information

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Advantages

Reduce human dependency Reduction in technical problems Power theft is not possible Sends alerts on power cuts and communication

updates Low consumption of energy Low cost for implementation High security Timely billing will be possible

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Conclusion

Solution for automation in energy sector Decreasing the cost which is spent for billing and

distribution of bills On ultra-low power MSP430, consumes very small

amount of energy for its operation The microcontroller MSP430 is cheaper Tamper proof so electricity theft can be reduced Beneficial for both consumer as well as energy supplier Technical errors and corruptions can be avoided Hence it is a required system in India…..

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Future scope

□ used as a remainder-over usage of current by modifying the software.

□ A mini printer can be interfaced to get a printed bill or details of billing.

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References

1) Muhammad Saadi, Rabeel Manzoor, Lunchakorn Wuttisittikulkij, Proposal for Low Cost GSM based Electric Meter for Efficient and Automated Meter Reading for Developing Countries, Proceedings of the World Congress on Engineering 2012, London, U.K., Vol II, pp. 1024–1027, July 4 - 6, 2012

2) Texas Instruments, MSP430x4xx Family User’s Guide (Rev. J), http://www.ti.com/lit/ug/slau056j/slau056j.pdf

3) Load Generation balance Report 2012-13. Retrieved on Thursday 02, 2013 from http://www.cea.nic.in/

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