Generally the over current device are sized according to the pure undistorted RMS current. For example miniature circuit breaker is calibrated to operate under pure sinusoidal current RMS. The miniature circuit breaker will trip when the sinusoidal RMS current exceeds the rating current. This current represents heat in the power supply. This can only be achieved by when the entire load in the power system is resistive.
In home we used electronic equipment such as computer television, battery changer and fluorescent lamp which considered as power electronic equipment. This non linear load produce harmonic current in power system. The harmonic current cause the waveform become non sinusoidal. This harmonic component can be measured as Total Harmonic Distortion (THD).
The issues appear that the effectiveness of the miniature circuit breaker to operate under harmonic influence current which the current waveform is non sinusoidal. In this research, the effect of harmonic will be focused on miniature circuit breaker than other protection device. Last year, there is a student doing research the effect of harmonic on over current relay.
EFFECT OF THE HARMONIC CURRENT ON THE MINIATURE CIRCUIT BREAKER_MOHD AKRAMIN MOHAMED NAWAWI_E3_2008_875002498_NI