Noninvasive current sensor for household appliances and compensation for installation variation

The lack of natural resources requires a more efficient use of energy. This study proposes a noninvasive coil current sensor for energy efficiency in the home. The proposed sensor is used to detect current in two-wire power cords used by household appliances. Moreover, the proposed sensor has no contact with the conductors in the power cords, ensuring a safe measurement process. Mathematical models and experiments are conducted to verify the characteristics and performance of the proposed device. In addition, this study develops relevant algorithms and the method for reducing installation variation. Using the developed algorithms, the measurement errors caused by an installation gap were reduced to less than 3%. The information provided by the current sensor supports home energy management systems and encourages energy-saving behaviors for every household member, resulting in an increasingly efficient energy usage.