Design and Construction of a GSM-Based Energy Meter
Chapter One
OBJECTIVE OF THE STUDY
The purpose of this project is the remote monitoring and control of the domestic energy meter; its aims includes: to design a circuit which continuously monitors the meter reading and sends message to electricity company, programming of the GSM MODEM with AT (Attention) command sequence, interfacing the programmable chip with the personal computer, interfacing the programmable chip with the energy meter, interfacing of GSM MODEM with the programmable chip, sending messages from the remote phone to control device.
CHAPTER TWO
LITERATURE REVIEW
An electricity meter or energy meter is a device that measures the amount of electric energy consumed by a residence, business, or an electrically powered device. Electricity meters are typically calibrated in billing units, the most common one being the kilowatt hour (kWh). The electric power company which supplies the electricity installs the electric meters to measure the amount of electricity consumed by each of its customers. [3] Researchers have proposed different implementation techniques for Automatic Mete Reading (AMR). One as discussed in this report is the GSM based Automatic Meter Reading System which uses the GSM network for communicating with the meter.
HISTORY OF ELECTRIC ENERGY METERS
DIRECT CURRENT (DC)
As commercial use of electric energy spread in the 1880s, it became increasingly important that an electric energy meter was required to properly bill customers for the cost of energy. Edison at first worked on a DC electromechanical meter with a direct reading register, but instead developed an electrochemical metering system, which used an electrolytic cell to totalize current consumption. At periodic intervals the plates were removed, weighed, and the customer billed. [3]
An early type of electrochemical meter used in the United Kingdom was the ‘Reason’ meter. This consisted of a vertically mounted glass structure with a mercury reservoir at the top of the meter. As current was drawn from the supply, electrochemical action transferred the mercury to the bottom of the column. Like all other DC meters, it recorded ampere-hours. Once the mercury pool was exhausted, the meter became an open circuit. It was therefore necessary for the consumer to pay for a further supply of electricity. The first accurate, recording electricity consumption meter was a DC meter by Dr Hermann Aron, who patented it in 1883. [3]
ALTERNATING CURRENT (AC)
The first specimen of the AC kilowatt-hour meter produced on the basis of Hungarian Ottó Bláthy’s patent and named after him. These were the first alternating-current watt-hour meters, known by the name of Bláthy-meters. Also around 1889, Elihu Thomson of the American General Electric company developed a recording watt meter (watt-hour meter) based on an ironless commutator motor. This meter overcame the disadvantages of the
electrochemical type and could operate on either alternating or direct current. [3] In 1894 Oliver Shallenberger of the Westinghouse Electric Corporation applied the induction principle previously used only in AC ampere-hour meters to produce a watt-hour meter of the modern electromechanical form, using an induction disk whose rotational speed was made proportional to the power in the circuit. Although the induction meter would only work on alternating current, it eliminated the delicate and troublesome commutator of the Thomson design. [3]
UNIT OF MEASUREMENT
The most common unit of measurement on the electricity meter is the kilowatt hour (kWh), which is equal to the amount of energy used by a load of one kilowatt over a period of one hour, or 3,600,000 joules. Demand is normally measured in watts, but averaged over a period, most often a quarter or half hour. Reactive power is measured in “thousands of volt-ampere reactive-hours”, (kvarh). By convention, a “lagging” or inductive load, such as a motor, will have positive reactive power. [4]
TYPES OF METERS
Electricity meters operate by continuously measuring the instantaneous voltage (volts) and current (amperes) to give energy used (in joules, kilowatt-hours etc.). The meters fall into two basic categories, electromechanical and electronic.
ELECTROMECHANICAL METERS
The electromechanical induction meter operates by counting the revolutions of a nonmagnetic, metal disc which rotates at a speed proportional to the power passing through the meter. The number of revolutions is thus proportional to the energy usage. The voltage coil consumes a small and relatively constant amount of power, typically around 2 watts which is ot registered on the meter. The current coil similarly consumes a small amount of power in proportion to the square of the current flowing through it, typically up to a couple of watts at full load, which is registered on the meter.
CHAPTER THREE
DESIGN AND CONSTRUCTION PROCEDURE
INTRODUCTION:
This chapter entails the design and construction procedure of the GSM Energy Meter detailing step by step the theoretical analysis, choice of components and values and construction and packaging materials. Indicating calculations, schematics and drawings. The design procedure is divided into hardware and software design as discussed below.
SYSTEM DESCRIPTION
The GSM Based Energy Meter is an electronic unit design to take real time energy
usage using a current sensing method which is then communicated to a microcontroller, who
takes the appropriate calculations and displays on an LCD. A GSM MODEM is incorporated
with the unit so as to make remote control of the meter unit by doing either of the following:
- Connect the unit to power Grid.
- Disconnect the unit from power Grid.
- Take meter reading.
- Recharge the meter unit.
- Reset the meter unit.
CHAPTER FOUR
PERFORMANCE AND COST EVALUATION
PERFORMANCE EVALUATION
This chapter describes the evaluations carried out of the system from simulation way through to final construction. Detailing the results obtained and the cost evaluation for each unit component of the system.
CHAPTER FIVE
CONCLUSIONS
SUMMARY
The GSM Based Energy Meter project as stated proffers solution to the deficiencies of traditional metering system. With the implementation of the GSM network system which is readily available. Man is on the way to ultimately derive the benefits in remote automation and control of electrical system. With this design fully implemented the cost associated with metering is reduced. Power theft at minimum, proper documentation and even distribution of
power to consumers is found to be more effective. Therefore it avoids human intervention, provides efficient meter reading, avoid the billing error and reduce the maintenance cost. It displays the corresponding information on LCD for user notification.
CONCLUSION
Modern civilization would be brought to its knees, if a crisis of electricity scarcity ever looms. The cusp of society would collapse. Therefore, the undeniable need for uninterruptible electricity is the prelude to development of any nation in the world today. From the design of the system and development, it is realised that the implementation of the GSM BASED ENERGY METER meets the objectives of its design as it was able to fully remote control the activities of the meter unit by doing the following making it beneficial to both utility company and consumer:
Connect the unit to power Grid.
Disconnect the unit from power Grid.
Take meter reading.
Recharge the meter unit.
Reset the meter unit.
Therefore meeting the requirements of providing a solution to power theft, load control, proper documentation of individual consumer energy usage over a period of time. Providing the power utility company to proper plan and design sufficient infrastructure equipment for power transmission.
RECOMMENDATIONS
Further development work can be done in the area of tampering in meters as this seem to be major setback, though as known no system is 100% safe. The use of tamper proof seals and labels, tamper resistant screws and locks and providing non-magnetic enclosure. Also the incorporation of consumer load control with the metering system would also be developed.
The implementation of other control methods such as the wireless communication over the internet as well as improvement in the cost of development and the incorporation of a Graphical user interface (GUI). With this development primary focus of research should be on the degree to which IT can accomplish large scale, permanent change for a better and sustainable Nigeria, and by extension the future of nations throughout the African continent especially in the area of power generation and transmission as this is a great bane to national development.
REFERENCES
- Electronic Energy Prepayment Meter Overview, Nigeria Technology News, http://www.nairaland.com/electronicenergyprepaymentoverview6486487/hrfh
http://en.wikipedia.org/wiki/electricenergymeter - Abhinandan Jain, Department of Electronics &Electrical Communication, PEC University of Technology, Chandigarh, India, Dilip Kumar, Department of Academic and Consultancy Services Division C-DAC,
- Mohali, India. Jyoti Kedia, Department of Electronics & Electrical Communication PEC University of Technology, Chandigarh, India.
- Design and Development of GSM based Energy Meter, International Journal of Computer Applications (0975 – 888) Volume 47– No.12, June 2012
- H.G.Rodney, Tan IEEE, C.H.Lee and V.H.Mok, (2007), Automatic Power Meter Reading system using GSM Network. The 8th International Power Engineering Conference, pp. 465 -469
- PHCN: BENEFITS OF THE NEW PREPAYMENT METERS http://www.naijatechguide.com/2012/11/phcn-benefits-of-new-prepayment
- A. Abdollahi, M. Dehghani, and N. Zamanzadeh,”SMS-based reconfigurable automatic meter reading system, IEEE International Conference Control Applications., Oct. 2007.pdf