| Summary: | 博士 === 國立台灣工業技術學院 === 電機工程技術研究所 === 84 === This dissertation presents the design and implementation of
the single-phase half-bridge and full-bridge switch-mode
rectifiers to yield near-unity power factor and low current
distortion on the utility side. The rectifiers can not only
function as ac/dc bidirectional power conversion, but also
improve the input and output performance. The average duty
cycle of the rectifier''s switch state is used to derive the dc
link voltage limit and design the parametric values for the
input inductance and dc link capacitance. By using the
predicted current control, the rectifiers can achieve fast
current response and low harmonic distortion. A low-pass filter
is introduced in the dc voltage control loop to eliminate the
second harmonic component .The delay time caused by the low-pass
filter is analyzed and improved. A small-signal model of the
power stage is developed to facilitate the root-locus analysis
of the control system. The proportional-integral controller can
then be designed to assure stable operation and yield the dc
voltage dip within acceptable range. Details concerning the
determination of controller''s gains are given. The operation
of the rectifier is conducted by the combined application of the
voltage and current control methods. A single-chip
microprocessor is used to implement the system for cost
reduction and reliability enhancement. A 1 kW prototype is built
to evaluate the performance of the half-bridge and full-bridge
rectification. Computer simulation and experiments are given to
verify the analysis. The results indicate that under rated
operation, the rectifiers possess a power factor of 0.99 and a
total harmonic distortion of current of less than 3% on the
input side, and fast dc voltage response with zero steady-state
error on the output side.
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