ELEC 431 Class notes
DC/AC Inverters
P.K. Jain
DC/AC inverters are used to produce controllable AC voltage (variable amplitude and
frequency).
Applications:
1. AC drive systems
2. AC source Uninterruptible Power Supply (UPS)
3. Alternative energy power so
ELEC 431
DC/AC Converters
P.K. Jain
Assignment #4
1. A load circuit for a bridge inverter is shown in the figure below. Voltage control
by single pulse modulation is employed. Determine the harmonic distortion factor
Kv for voltage vL appearing across the
ELEC 431 Class notes
Isolated DC/DC Converters
P.K. Jain
Isolated DC/DC converters can be derived from those three basic DC/DC converters (i.e. Buck,
Boost or Buck-Boost converter)
Features of isolated DC/DC converters:
1. Provide electrical isolation
2.
Formulas
Rectifiers
Vo
2 2V
sin nt
n
n1
2V
Vo
Vo
xt
Vo
0.9V
4X
cos
2 2V
Vo
2V
2 2V
cos 1
cos cos
cos
2 I oLs
2 I d Ls
Vo
2V
2V
1 cos
Is Io
2 2
PF
0.9
2
1 cos
PF
1 cos
PF 0.9 cos
DC/DC Converters
Pcon,S Rsw I sw, RMS
f
Vo
Vo 1 d
ELEC 431
Resonant Converters/Inverters
P.K. Jain
Assignment #5
1. In the series resonant inverter of Figure 1, vi = 500V, Ts = 10s. The load
parameters are: R = 1.2, L = 10 , 1/C = 10. If the variable frequency
control is used to regulate the output, perf
ELEC 431
AC/DC - Uncontrolled Rectifiers
P.K. Jain
Assignment # 1
1. A single phase full-wave diode rectifier of Fig. 1 is connected to a 220V AC source to
feed a dc motor with a back EMF of 150 V. The motor has a winding resistance of 0.5
and the induct
ELEC 431
AC/DC - Controlled Rectifiers
P.K. Jain
Assignment # 2
1. A single phase full-wave controlled rectifier is connected to a 220V AC source to feed a
dc motor with a back EMF of 150 V. The motor has a winding resistance of 0.5 ohm and
the inductance
Quiz # 2
ELEC 431
[out of 20]
No formula sheet is allowed.
1. A single-phase, full-wave controlled rectifier employing SCRs, with a
freewheeling diode connected at the output of the rectifier, is connected to a 110V
AC source and feeding a dc motor having
ELEC 431 Class notes
I.
Basic DC/DC Converters
P.K. Jain
Converters: convert DC voltage from one level to another DC level
The three basic types of DC/DC converter:
1) Buck converter step down input DC voltage
2) Boost converter step up input DC voltage
Quiz # 4
ELEC 431
[out of 20]
No formula sheet is allowed.
1. Draw the boost and buck-boost converters, label their input and output voltages;
and derive their corresponding voltage gain equations in continuous conduction
mode.
2. In a boost converter, th
ELEC431Classnotes
AC/DCUncontrolledRectifiers
P.K.Jain
Rectifiers: converts AC to DC
There are two types of rectifiers: Uncontrolled rectifiers and controlled rectifiers
Uncontrolled rectifier:
also called full bridge diode rectifier the rectified voltage
ELEC 431 Class notes
Resonant DC/DC Converters
P.K. Jain
Resonant converters are used to reduce/eliminate the switching losses. There are three basic
types of the resonant DC/DC converters:
1. Series resonant converter
2. Parallel resonant converter
3. Se
Quiz # 3
ELEC 431
[out of 20]
No formula sheet is allowed.
1. In a buck converter, the output voltage (Vo) is kept constant at 10V by controlling
the duty cycle of the switch. The input voltage (Vi) range is: 20 - 100V, the
output power is 200W, output ca
ELEC431Classnotes
AC/DCControlledRectifiers
P.K.Jain
Controlled rectifier
Unlike the uncontrolled rectifiers, by replacing the diodes with thyristors, the average output
voltage can be controlled by adjusting the turn-on time or the control angle, denoted
Quiz # 1
ELEC 431
No formula sheet is allowed.
1.
A single-phase, full-wave diode rectifier is connected to a 120V AC source and
feeding a dc motor having an armature inductor large enough to assume a ripple
free dc current, an armature resistance and a b
ELEC 431
DC/DC Converters
P.K. Jain
Assignment # 3
1. In a buck converter, consider all components to be ideal; the output voltage is
kept constant at 5V by controlling the duty cycle. The input voltage varies
between 10V to 40 V, the output power is grea