In electronicpower supplies there is often a need to isolate the output from the input andreduce the weight and cost of the unit. In other applications, such as inaircraft, there is a strong incentive to minimize weight. These objectives arebest achieved by using a relatively high frequency transformer. Thus, inaircraft the frequency of transformers is typically 400Hz, while in electronicpower supplies the frequency of transformers may range from 5kHz to 50kHz