Design of a Smart Energy Meter with Overload Trip Facilities

Abstract

Nowadays for running the domestic electric appliances like lamp, Motor and Air Conditioner, one of the most commonly used energy source is Electric energy. This is the reason that electric energy has become quite important in the daily life of people. In Pakistan, WAPDA (Water and Power Development Authority) is the main company whose sole purpose is the generation and distribution of electrical energy throughout the country and the consumer will have to pay according to the use of electrical energy. There are other companies that also generate electrical energy and distribute it to some of the area like K-electric and IPPS. So, a consumer knows how much energy has been consumed by the domestic electrical appliances when an employee of WAPDA checks the energy meter once a month and charged according to the units consumed in a month. In such a manner, a consumer does not get any information that how much energy has been consumed and he will have to pay a large amount of bill as he is unaware of his energy consumption. This way he is unable to manage his load according to his requirements. In this project, we are going to design a prototype of Three Phase smart energy meter. In order to make a conventional energy meter smart we are going to interface a microcontroller and GSM module with the energy meter. The purpose of microcontroller is that through this we are going to measure current and voltage for all the three phases and from these readings power will be calculated because we need to know the consumption before its management. For each phase, a user can set a predefined value of load, whenever this limit exceeds the user will get a message for that phase that the "system is overload". This will inform him about his load and after that he will manage his load accordingly. So, our designed prototype has got two advantages, first one is that user can set a threshold value of energy and the other one is that consumer will be informed whenever the threshold value of energy is exceeded. This will be beneficial for the user and also for the electric energy providing company. The meter will be trip on high usage of energy and WAPDA will be informed whenever there is short circuit. So, this can also provide safety for the domestic users. In the designed project, we have proposed different ways of reclosing the relay for each and every Phase as we have three Phases. User can reclose the first Phase just by pressing a touch button while the second phase will reclose automatically after a delay of one minute. A user can change this delay. The third Phase will reclose after a delay of two minutes in a condition that the user has managed his load otherwise it will remain open.