U.S. Particle Accelerator School

Accelerator Power Electronics Engineering

Sponsor:

University of New Mexico

Course Name:

Accelerator Power Electronics Engineering

Instructors:

Paul Bellomo and James Sebek, SLAC National Accelerator Lab


Purpose and Audience
This course is an introduction to the field of accelerator power electronics and is suitable for advanced undergraduate and graduate students. The course is also appropriate for engineers and technicians working on power electronics as well as others in accelerator-related fields who wish to learn about the electrical systems powering accelerator magnets, kickers, klystrons, etc.

Prerequisites
The student should have a good knowledge of basic electronics, such as the material in the textbooks: Electronics Fundamentals: Circuits, Devices and Applications by Thomas L. Floyd and David L. Buchla or Foundations of Analog and Digital Electronic Circuits by Anant Agarwal and Jeffrey Lang.  The latter is the text for MIT 6.002, the course notes and lectures of which are available through MIT OpenCourseWare at https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-002-circuits-and-electronics-spring-2007/index.htm The student should understand linear algebra at an undergraduate level, have a working knowledge of calculus, and some familiarity with first and second order ordinary linear differential equations.  A working knowledge of computer aided design will also be helpful.  (A laboratory session will use the LTspice simulation software from Analog Devices.  The laboratory will include an introduction to LTspice that will be sufficient to complete the assignments.)

It is the responsibility of the student to ensure that he or she meets the course prerequisites or has equivalent experience.

Objectives
This course will focus on the fundamental principles of power electronics circuits and systems used in particle accelerators.  In daily lectures, the instructors will give theoretical presentations of various power electronics systems, followed up with practical examples of systems in use in accelerators.  Daily homework and one computer laboratory will reinforce these concepts.  The course aims to emphasize the intuitive concepts of the systems, using mathematical derivations only when needed to prove concepts or clarify this intuition.

Instructional Method
This course includes a series of daily lectures in both the mornings and afternoons. In the last half of the week there will be a half day laboratory session, which will consist of computer simulations of power conversion circuits, previously covered in class, using LTspice.  Students will be required to write and submit a report for the laboratory session.  The instructors will assign additional problems each day, based on that day’s lectures, for completion outside of scheduled class time.  The instructors will also be available for discussion and questions outside of the scheduled class time.  The daily homework problems will be graded in a timely fashion to provide feedback.

Course Content
The course covers the types of power electronics equipment typically used in accelerators to power coils of magnets for beam focusing and bending and RF power sources for beam generation, acceleration, steering, and focusing.  It will emphasize the specification of complete power systems for the proper operation of, and matching to, magnet, capacitor, and klystron loads.  The first part of the course will discuss the AC power concepts important to provide the raw power to the electronics.  These concepts include input line voltage, single line diagrams, power factor, harmonic distortion, etc.  The largest fraction of the course is devoted to power electronic circuits for “warm” and superconducting DC magnet applications.  This section will cover standard DC power supply design topologies.  In it we will also discuss the selection of appropriate power elements for the various applications, concepts of transformer design, high performance feedback systems, and interfaces to the accelerator control system.  In another course section we will present an introduction to pulsed power applications for loads such as septum magnets, kicker magnets, and klystrons.  This section will include transmission line theory, impedance matching, classical pulse forming networks, and newer solid-state topologies.  (Students interested in learning more about pulsed power systems should consider enrolling in the Pulsed Power Engineering course /programs/2019/newmexico/courses/pulsed-power-engineering given in the second week of the school.) In another course section, we will focus on specifying, improving, and maintaining the reliability of power electronics required for modern accelerators.  Finally, we will address safety issues working around high voltage, high power systems, including personnel safety, machine protection, and code compliance.

Reading Requirements
Extensive class notes will be provided that will serve as the primary reference.  These notes will be a slightly revised version of those used in 2017, a link to which can be found at /materials/17NIU/niu-power-electronics.shtml

A useful textbook that covers much of the material to be presented in this course is "Fundamentals of Power Electronics" by Robert W. Erickson and Dragan Maksimovic, Springer, Second Edition, 2001.  (Course text to be provided by the USPAS to the student at the school.)

Suggested additional power electronics references (neither mandatory nor provided by USPAS) are:
“Power Electronics” by Daniel W. Hart, Valparaiso University, McGraw-Hill, 1st edition, 2011
"Elements of Power Electronics" by Philip T. Krein, University of Illinois, Oxford University Press, Second Edition, 2014
"Principles of Power Electronics", by John G. Kassakian, Martin F. Schlecht and George C. Verghese, MIT, Addison-Wesley, 1991
"Power Electronics: Converters, Applications, and Design" by Ned Mohan, Tore M. Undeland, and William P. Robbins, University of Minnesota, John Wiley, Third Edition, 2003.

Credit Requirements
The basis for student evaluations are performance on homework assignments (80% of final grade), and a computer/lab session (20% of final grade).


University of New Mexico course number: ECE 595-010, 011, 012
Indiana University course number: Physics 671, Advanced Topics in Accelerator Physics
Michigan State University course number: PHY 963, "U.S. Particle Accelerator School"
MIT course number: 8.790, "Accelerator Physics"