I am having trouble pinning down why the relative permeability of a transformer core will not directly affect the output voltage. In fact the voltage is determined by the turns ratio and is independent of mu of core material.(adsbygoogle = window.adsbygoogle || []).push({});

Given this where is the flaw in the following reasoning:

Induced field strength H is proportional to current in primary coil, H=k I (to be exact , integral H*dl = If+dD/dt)

Magnetic flux density in core is B=mu H

Voltage in single turn of secondary is proportional to rate of change of B; V=A dB/dt = A mu dH/dt = A mu k dI/dt

From this (apparently specious) reasoning, output voltage depends on mu.

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# Transformer output indepedent of core permeability

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