Abstract:
Typical switched-mode power supplies employ diode rectifiers for the AC to DC
conversion. They draw input current in short pulses rather than in smooth sine waves and
this puts stress on the wiring, circuit breakers and even distribution equipment provided
by utilities. This type of utility interface generates harmonics and both of the input power
factor (PF) and total harmonic distortion (THD) are poor. To minimize the stresses and
maximize the power handling capabilities, active power factor correction (PFC) circuitry
can be added to improve the shape of the input current. This work is aimed at providing a
simple design method for power factor correction (PFC) boost converter for a non-linear
power system to improve the disturbance rejection and speed of response of the
conventional nonlinear cascade controller. Model based cascade controller design is
presented for the control of PFC boost converters. Also, a dead band relay is introduced
in the voltage loop to improve the disturbance rejection and speed of response of the PFC
boost converter. Circuit implementation of the proposed control scheme is presented and
simulation results are included to demonstrate the effectiveness of the proposed design
scheme. The outcome indicated that resultant power factor is over 0.99, the total
harmonic distortion of supply current is less than 2.9% and the efficiency of the converter
is 93% at full load. It is recommended that a MOSFET based switching device could be
used to improve the system.
Description:
A Dissertation in the DEPARTMENT OF ELECTRICAL AND AUTOMOTIVE
TECHNOLOGY EDUCATION, Faculty of TECHNICAL EDUCATION, submitted
to the School of Graduate Studies, University of Education, Winneba in partial
fulfillment of the Requirement for the award of the Master of Technology Education
(Electrical/Electronic Technology) degree.
DECEMBER, 2016