Development of a GSM-Based Smart Energy Meter

Abstract

In this work, a GSM based smart energy meter has been developed. This smart meter can be remotely queried and recharged via a GSM link. The designed smart meter was built around the ATmega32 Microcontroller programmed in C, which serves as the main controller for the circuit and theADE7755 metering chip which senses the load current and voltage and gives an output that is equivalent to their product. Wireless communication between the meter and registered GSM line was established with the aid of SIM900 GSM module using AT-commands. A Token Generator was created in Visual Basic Environment which was used to generate tokens/pin code to recharge the meter. The token is an encryption of the Meter Serial Number, Supply Group Code (SGC) and the number of units that a consumer wishes to purchase. The microcontroller is able decrypts this information, cross check it, before it is accepted. If the token is invalid, an alarm is triggered indicating an invalid token, and this is displayed on the LCD screen. A comparison of the readings from the designed meter and that from a conventional wattmeter shows that the reading from the designed meter is sufficiently accurate as the average percentage error is about 0.6%. The reading can therefore be said to be a true reflection of the energy actually consumed.