Transformer and Auto Transformer
Q1: What do I need to know to solve Ideal Transformer,
Transformer, and autotransformer problems?
Q2: What does it mean referred to primary or secondary side?
Q3: How to draw phasor diagram ?
current transformer with a bar primary has 250 turns
in it secondary winding. the resistance and reactance of the
secondary circuit are 1.4 ohms and 1.1 ohms respectively including
the transformer winding. when 5A current flows in the secondary
winding, the magnetism mmf is 80 AT and iron lost is 1.1w.
determine the following (i) ratio error (ii) phase angle error
Compare the differences and similarities between the Current
Transformer (CT) and Rogowski coils. Include drawings, schematic
and equations in your answer.
Define what an electrical potential is
Define what a current is
Define polarized
Why are cells described as polarized?
How do cells maintain their resting membrane potential?
A current transformer rated 500/5 A, 20 VA, 50 Hz has
a turns ratio of 1:99. Its
resistance aand leakage reluctance of the secondary winding are 0.4
Ω and 0.35 Ω
respectively. At rated non-inductive burden, the inphase and
quadrature components of
the exciting mmf are 6 AT and 8 AT respectively. Determine the
current and phase angle error.
The efficiency of a 400-kVA, single-phase, 60-Hz transformer is
98.77% when delivering full-load current at 0.8 power factor, and
99.13% with half-rated current at unity power factor. calculate:
(a) The iron loss. (b) the full-load copper loss. (c) the
efficiency at 3/4 load, 0.9 power factor