[PDF] Pulse Width Modulation For Power Converters by Grahame Holmes

Preface

The work introduced on this e book provides a normal strategy to the event of fastened switching frequency pulse width-modulated (PWM) methods to swimsuit hard-switched converters. It’s proven that modulation of, and ensuing spectrum for, the half-bridge single-phase inverter kinds the fundamental constructing block from which the spectral content material of modulated single- part, three-phase, or multiphase, two-level, three-level, or multilevel, voltage hyperlink and present hyperlink converters can readily be discerned.

The idea ofharmonic distortion is used because the efficiency index to check all generally encountered modulation algorithms. Particularly, whole harmonic distortion (THO), weighted whole harmonic distortion (WTHD), and harmonic distortion criterion particularly designed to entry motor copper losses are used as efficiency indices.

The idea of minimal harmonic distortion, which kinds the underlying foundation of comparability of the work introduced on this e book, results in the identification of the basics of PWM as:

– Energetic change pulse width willpower.

– Energetic change pulse placement inside a switching interval.

– Energetic change pulse sequence throughout switching intervals.

The advantage of this generalized strategy is that after the frequent threads of PWM are recognized, the collection of a PWM technique for any converter topology turns into instantly apparent, and the one selections remaining are to trade-off the “very best” efficiency towards price and problem of implementation, and secondary issues. Moreover, the efficiency to be anticipated from a specific converter topology and modulation technique could be shortly and simply recognized with out complicated evaluation, in order that knowledgeable tradeoffs could be made concerning the implementation of a PWM algorithm for any explicit utility.

All theoretical developments have been confirmed both by simulation or experiment. Inverter implementation particulars have been included on the finish ofthe textual content to deal with sensible issues. Readers will in all probability word the absence of any closed loop points on this textual content. Whereas initially such materials was meant to be included, it quickly turned obvious that the inclusion ofthis materials would require an extra quantity. An additional e book treating this topic is in preparation.

Acknowledgments 

The authors are indebted to their graduate college students, who’ve contributed significantly to the manufacturing of this e book by way of their Ph.D. theses. Particularly the vital work of Daniel Zmood (Chapter 7), Ahmet Hava (Chapter 8) and Brendan McGrath (Chapter 11) are particularly acknowledged. As well as, quite a few different graduate college students have additionally assisted with the manufacturing ofthis e book each by means of their technical contributions in addition to by means of detailed proof-reading of this textual content.

The second writer (Lipo) additionally needs to thank the David Grainger Basis and Saint John’s School ofCambridge College for funding and amenities supplied respectively. Lastly, we want to thank our fantastic and loving wives, Sophie Holmes and Chris Lipo, for nuturing and supporting us over the previous 5 years as we have now written this e book.