08-17-2017, 12:32 AM
A Single-Phase High Power Factor Rectifier,
Based on a Two-Quadrant Shunt Active Filter
[attachment=512]
Abstract
This paper presents a new technique to improve the
input power factor of a single-phase rectifier followed by an
inductive filter. It consists in the employment of a two-quadrant
active power filter, based on a conventional bidirectional DC-DC
converter, connected to the output side of the diode bridge. This
technique allows the extension of this rectifier range operation in
the continuous conduction mode.
INTRODUCTION
THE increasing of the electronic devices in industry and
residences has created a major concern on the electric
power quality issue, due to the fact that these equipments
draw a current with high harmonic content from the grid. The
devices which present this characteristic are known as
nonlinear loads.
SYSTEM MODELING AND CONTROL STRATEGY
There are two main control strategies used in single-phase
active power filter control: the active power filter current
control and input current control. Both strategies require
voltage and current control. The APF DC-link voltage (Vcf)
control is responsible for the system active power flow
control, since the APF active power flow must be zero,
besides the components losses. The current control is
responsible for the input current shape control, which must be
a sine waveform in phase with the input voltage.
CONCLUSION
This paper has presented an active power filter topology,
based on a bidirectional DC-DC two-quadrant converter,
applied for the power factor correction of a single-phase
rectifier followed by an inductive filter. Theoretical analyses
were detailed, summarizing the main load characteristics and
the load operation with the APF. Moreover, the proposed
control strategy, system modeling and prototype design were
shown.