1.8 Figure shows an inductor made up of two C-cores. Each core has area Ac and mean length lc. There are two air gaps, each of length g and effective area Ag. Finally, there are two N-turn coils, one on each of the C-cores. Assuming infinite core permeability and for cores of dimensions

Cross-sectional area: Ac = Ag = 38.7 cm2

Core-length: lc = 45 cm

Gap length: g = 0.12 cm

a. Calculate the number of turns required to achieve an inductance of 12.2 mH, assuming infinite core permeability and that the coils are connected in series. Since the number of turns must be an integer, your answer must be rounded to the nearest integer. Calculated the actual inductance value based upon the resultant number of turns.

b. The inductance can be fine-turned by adjusting the air-gap length to achieve the desired inductance. Based upon the number of turns found in part (a), calculate the air-gap length required to achieve the desired inductance of 12.2 mH.

c. Based upon this final inductor design, calculate the inductor current which will produce a core flux density of 1.5T.

Transcribed Image Text:

Coil 1 N-turn C-core: Area A. mean length . permeability a Air gap: Area A length g Coil 2 N-turn Coil 1 N-turn C-core: Area A. mean length . permeability a Air gap: Area A length g Coil 2 N-turn