Abstract:
111th the instail~ti~n of an ever increasing
number of transformer sub-stations in built un Rreas.
the noise emitted by the transformer has bec-)me a nrnri (,m of or-~'rir- concern. Tn this dissertati-)n; an a
at t-met is made to revie7r the r.resent day kno1arledge on
the subject of transformer n~iso. Though all the major
sources of noise are listed, -particular attention is
given t) the ma--netostriction nro-)erties of the core
material., since m<agnetostriction is 'ono rn to be the chief source of dob1e fref7uenc., "hum" emitted by the
transformer. Theoretical and design considerations affecting the level of transformer noise are discussed
in some detail and the characteristics of noise with
na.rticular reference to the human ear are examined
critically. Various methods of limitation and reduction
of transformer noise are described and it is shown that economic considerations do not usually permit the uuse of very lov noise levels in commercial transformers.
