0195136047.pdf

PROBLEMS 61

L 11 L 22

i 1 i 2

v 1 v 2

+

−

+

−

M

(a)

L 11 L 22

i 1 i 2

v 1 v 2

−

+

−

+

M

(b)

Figure P1.2.32

i 2

i 1

v 2

v 1 v 3

L 22

L (^12) L
13 L^23
L 11 L 33

• − − +


• −
  i 3
  Figure P1.2.34
  18 Ω 2 Ω
  Ideal
  transformer
  Ideal
  transformer
  vin =
  18 sin 10t V
  Vout (t)
  3:1 1:2
  36 Ω 3 Ω


• 
  

  −

  
  


• 
  

  −
  Figure P1.2.36
  *1.2.37A 60-Hz, 100-kVA, 2400/240-V (rms) transformer
  is used as a step-down transformer from a trans-
  mission line to a distribution system. Consider the
  transformer to be ideal.
  (a) Find the turns ratio.
  (b) What secondary load resistance will cause the
  transformer to be fully loaded at rated voltage
  (i.e., delivering the rated kVA), and what is
  the corresponding primary current?
  (c) Determine the value of the load resistance
  referred to the primary side of the transformer.
  1.2.38A transformer is rated 10 kVA, 220:110 V (rms).
  Consider it an ideal transformer.
  (a) Compute the turns ratio and the winding cur-
  rent ratings.
  (b) If a 2-load resistance is connected across the
  110-V winding, what are the currents in the
  high-voltage and low-voltage windings when
  rated voltage is applied to the 220-V primary?
  (c) Find the equivalent load resistance referred to
  the 220-V side.
  1.3.1Some element voltages and currents are given in
  the network configuration of Figure P1.3.1. De-