This work develops an automated household utility power monitoring system and data logging in real-time. It utilizes the Arduino Uno Rev3 Microcontroller board intended for use in conjunction with the ATmega328 chip. For monitoring these parameters, it will be connected to a current transformer through the current and voltage sensor circuit. The system will convert these raw data to digital input for data acquisition and will log these to an SD card by the SD/MMC shield module for data retention in case of power failures. The system is also equipped with DS1307 serial RTC (Real-Time Clock) chip which is responsible for providing real time clock and date needed in the data logging operation. Results and findings indicated that the device has indeed successfully performed its desired function as an automated household utility power monitoring system. As such it will display in real-time, the consumed average power in watt along with its price. This will serve as an assessment parameter in order to measure the acceptability, performance relative to functionality, and marketability of the accomplished technology.

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This paper presents a way of generating a variable frequency sinusoidal signal in conjunction to the developed spread spectrum frequency modulation technique that is used to suppress the EMI caused by high switching frequencies. These are implemented through Verilog Hardware Descriptive Language (Verilog HDL) and synthesized on Altera DE2-70 FPGA board using Quartus tool chain to satisfy the low cost requirement and flexibility which are verified through (1) Modelsim simulations, (2) Debussy simulations and by (3) actual digital to analog conversion using DAC7541. For experimental validation, series of measurements are done on the output of the inverter prototype driven by the generated SPWM signal. Measurement results at the output SPWM show that the applied technique may have caused an increase in THD by 0.092%, 0.039% and 0.087% at frequencies 50 Hz, 60 Hz and 70 Hz respectively, but it has significantly reduced the EMI peak with at least 12.8dB.