Page 150 - Rashid, Power Electronics Handbook

10

Diode Recti®ers

Yim-Shu Lee, Ph.D. and 10.1 Introduction ...................................................................................... 139
Martin H. L. Chow, Ph.D. 10.2 Single-Phase Diode Recti®ers................................................................ 139
Department of Electronic and 10.2.1 Single-Phase Half-Wave Recti®ers 10.2.2 Single-Phase Full-Wave Recti®ers
Information Engineering 10.2.3 Performance Parameters 10.2.4 Design Considerations
The Hong Kong Polytechnic 10.3 Three-Phase Diode Recti®ers ................................................................ 144
University,
Hung Hom, Hong Kong 10.3.1 Three-Phase Star Recti®ers 10.3.2 Three-Phase Bridge Recti®ers 10.3.3 Operation
of Recti®ers with Finite Source Inductance
10.4 Poly-Phase Diode Recti®ers .................................................................. 148
10.4.1 Six-Phase Star Recti®er 10.4.2 Six-Phase Series Bridge Recti®er 10.4.3 Six-Phase
Parallel Bridge Recti®er
10.5 Filtering Systems in Recti®er Circuits..................................................... 150
10.5.1 Inductive-Input dc Filters 10.5.2 Capactive-Input dc Filters
10.6 High-Frequency Diode Recti®er Circuits ................................................ 154
10.6.1 Forward Recti®er Diode, Flywheel Diode, and Magnetic-Reset Clamping Diode in a
Forward Converter 10.6.2 Flyback Recti®er Diode and Clamping Diode in a Flyback
Converter 10.6.3 Design Considerations 10.6.4 Precautions in Interpreting Simulation
Results
References ......................................................................................... 168

10.1 Introduction half-wave recti®ers and single-phase full-wave recti®ers. In the
following subsections, the operations of these recti®er circuits
This chapter is concerned with the application and design of are examined and their performances are analyzed and
diode recti®er circuits. It covers single-phase, three-phase, compared in tabular form. For the sake of simplicity the
poly-phase and high-frequency recti®er circuits [1, 2]. The diodes are considered to be ideal, that is, they have zero
objectives of this chapter are: forward voltage drop and reverse recovery time. This assump-
tion is generally valid for the case of diode recti®ers that use
To enable readers to understand the operation of typical
the mains, a low-frequency source, as the input, and when the
recti®er circuits.
forward voltage drop is small compared with the peak voltage
To enable readers to appreciate the different qualities of
of the mains. Furthermore, it is assumed that the load is purely
recti®ers required for different applications.
resistive such that load voltage and load current have similar
To enable the reader to design practical recti®er circuits.
waveforms. In Section 10.5 the effects of both inductive and
The high-frequency recti®er waveforms given are obtained capacitive load on a diode recti®er are considered in detail.
from PSpice simulations, [3–5] which take into account the
secondary effects of stray and parasitic components. In this
way, these waveforms will closely resemble real waveforms. 10.2.1 Single-Phase Half-Wave Rectifiers
These waveforms are particularly useful to help designers
The simplest single-phase diode recti®er is the single-phase
determine the practical voltage, current, and other ratings of
half-wave recti®er. A single-phase half-wave recti®er with
high-frequency recti®ers.
resistive load is shown in Fig. 10.1. The circuit consists of
only one diode that is usually fed with a transformer second-
ary as shown. During the positive half-cycle of the transformer
10.2 Single-Phase Diode Rectifiers secondary voltage, diode D conducts. During the negative
half-cycle, diode D stops conducting. Assuming that the
There are two types of single-phase diode recti®er that convert transformer has zero internal impedance and provides perfect
a single-phase ac supply into a dc voltage, namely, single-phase sinusoidal voltage on its secondary winding, the voltage and

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