A D.C power supply unit provides an output power of 60V at no load and 56V at full load. The ripple component of the output voltage is 1.25 V rms. Determine the percentage:

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 (I) Voltage regulation

Soln

% voltage regulation = {(no load voltage - full load voltage)/(full load voltage)} x 100

 ={ (60-56)/60} x 100

= 7.1425%

(II) ripple

Soln

Ripple factor = V ac(rms) /V dc

                        = 1.25 v/ 56V

                         = 2.232%

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