|MadSci Network: Engineering|
The basic difference is in the control of the shape of the wave as it travels through the transformer. For power transformers, a little distortion of the wave shape is of no consequence to a light bulb or and AC motor, within reason, of course. You note the application of a camera electronic flash where a capacitor is discharged through a pulse transformer... For electronic applications, efficiency is of great importance in extending battery life. And, where large power station transformers have oil cooling and fans to get rid of the heating due to inefficiency, heating can be a big consideration in electronic designs. Much more care is taken in the design of a pulse transformer to minimize wave form distortion and losses than for any power transformer. If wave form distortion was ever a problem for power transformers, that design evolution ended decades ago. There is still a little work being done in power transformer insulation design as better materials become available, and in the coolant area where the last major change required the removal of coolant containing PCB's.
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