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Transformers physics

Transformer design is based on some simple physical principles like Faraday's and Ampere's laws, which are integral formulations of some Maxwell's equations. Intuitively, a transformer is a device in which two windigns are mutually coupled by a common magnetic flux, the currents adjusting themselves in order to mimize it. We will show in the following that for a perfect transformer with tex2html_wrap_inline278 turns on the input and tex2html_wrap_inline280 turns on the output, the ration between input and ouput voltages is tex2html_wrap_inline282, while the currents ration is tex2html_wrap_inline284. From those relations, it can be deduced that an input impedance Z appears as tex2html_wrap_inline288 on the ouput. This ability to transform impedances will be crucial in audio applications.





Stephane Puechmorel
Tue Jul 8 14:22:42 WET DST 1997