Transcript lecture10

‫بسم هللا الرحمن الرحيم‬
The Islamic University of Gaza
Faculty of Engineering
Electrical Engineering Department
POWER ELECTRONICS
EELE 5450 — Summer 2012
Instructor: Eng. Jalal Al Roumy
Lecture 10
Chapter Four
Single-Phase Full-Wave Inductive Load circuit
The output
Assume
Both
thyristors
thatdcthe
voltage
are
inductance
triggered
ED williswith
be
sufficiently
function
the same
of
large,
delay
firing
soangle,
angle:
that each
hence
Scr conducts
they
share thefor
load
a period
current
ofequally.
180 degree.(
The load
conduction
currentcurrent
is shownis
continuous).
to
be constant dc (due to large value of inductance)
Chapter Four
Single-Phase Full-Wave Inductive Load circuit
The output dc voltage ED will be function of firing angle:
The
The output
output dc
dc voltage
voltage E
EDD is:
is:
o
Maximum
Maximum when
when α=
α=0
o
Zero
Zero when
when α=
α=90
o
Negative
Negative maximum
maximum when
when α=
α=180
o
o
α90<α
<180<180
 ????
 ????
Chapter Four
Single-Phase Full-Wave Inductive Load circuit
Chapter Four
A constant
The
A single-Phase
load voltage
load current
cannot
Full-Wave
be
is maintained
negative
Phase-Controlled
by free-wheeling
Converter
current through with
the diode:
Free-Wheeling Diode
End of Lecture