Course Websites

• Power and Energy Systems

https://canvas.illinois.edu/courses/36511

Fundamentals of circuits for electrical energy processing. Discusses power electronics as a vital enabler for future energy. Switching converter principles, harmonics, pulse-width modulation, phase control, and phase modulation, dc-dc, ac-dc, and dc-ac, power converters. Alternative and renewable energy applications. High-performance power supply circuits. Power components, including capacitors, magnetic components and power semiconductor switching devices. Considerations in solar, wind, and fuel cell power.

To develop all major power electronics concepts, from both systems and components perspectives. To present major design considerations for switching power conversion, including operation and control choices, harmonics and filtering, circuit models of real sources and devices, magnetics design, and passive and active component behavior.

• Background: electricity conversion needs, history, the switch matrix
• Switch matrix operation and representation: circuit laws as constraints, switch types and examples, control alternatives
• dc-dc converters and applications. High-performance power supplies.
• ac-dc/dc-ac converters and alternative energy applications. Introduction to hybrid cars, solar energy, wind systems, and fuel cells.
• Models for real sources and loads, power filters for source interfaces
• Real capacitors and their applications in converters
• Magnetics for power electronics applications
• Power electronic switching devices: sources of loss and basic thermal calculations, typical power switch types and models

Covers the fundamentals of electronics for electrical energy processing, and applications to renewable and alternative energy. The course seeks to develop all major power electronics concepts, from both systems and components perspectives. It presents major design considerations for switching power conversion, including operation and control choices, harmonics and filtering, circuit models of real sources and devices, magnetics design, and passive and active component behavior. These are presented in applications context for diverse situations, including solar and wind energy conversion, hybrid and electric cars, high-performance computer power supplies, switching audio amplifiers, solid-state lighting, utility control and smart grids, portable power, and many others.

Topics:

• Background: electricity conversion needs, history, the switch matrix
• Switch matrix operation and representation: circuit laws as constraints, switch types and examples, control alternatives
• dc-dc converters and applications. High-performance power supplies, solid-state lighting and portable power.
• ac-dc/dc-ac converters and alternative energy applications. Introduction to hybrid cars, solar energy, wind systems, and switching amplifiers.
• Models for real sources and loads, power filters for source interfaces
• Real capacitors and their applications in converters
• Magnetics for power electronics applications
• Power electronic switching devices: sources of loss and basic thermal calculations, typical power switch types and models

A variety of analytical and simulation examples.

See ECE 469.

• Introductory linear systems
• Electronic circuits and devices

P. T. Krein, Elements of Power Electronics, Oxford Univ. Press.

Engineering Science: 2 credits
Engineering Design: 1 credit

Modern electrical energy systems are increasingly dominated by electronics for energy processing and management. The primary goal of the course is to give students a foundation for analysis and design of electronic circuits for conversion and control of electrical energy. The work is placed in the context of modern energy challenges, including alternative electricity resources and efficient energy applications. An additional goal is to help students fit together their complete electrical engineering background to tackle practical design problems. The course presents concepts, fundamental analysis tools, practical considerations for design, and a range of power electronics applications. The letter codes refer to the Department-wide program outcomes list.

Intended course outcomes emphasize electrical engineering synthesis. Students need to assemble their body of knowledge to address diverse energy applications. The intended plan is to help students understand depth issues: evaluating a problem and application from all directions, seeking to understand it in depth before embarking on a solution. Breadth is a primary feature of the course, since power electronics is becoming ubiquitous in all devices and systems that use or process electrical energy. The course emphasizes applications as diverse as electric vehicles, solar panels, high-performance power supplies for low-voltage digital circuits, solid-state lighting, battery charging, grid interfaces, and a host of others. Students are taught professionalism aspects, such as learning how to establish detailed specifications from a general set of user requirements, how to look beyond basic requirements to understand user needs, how attributes of a design may meet literal requirements but still lead to an unacceptable solution, how to understand cross-disciplinary team strategies from addressing major application challenges, and learning how to consider broad aspects and implications of global energy challenges. The lifelong learning aspects are also emphasized, since applications change quickly and new needs arise every day. The course includes extensive demonstrations and physical devices to help students get a literal feel for how problems are addressed and what extra considerations limit designs.

A. By the time of Exam No. 1 (after about 15 lectures), the students should be able to do the following:

1. Discuss energy conversion needs of society, and describe the purpose of power electronics in addressing these needs. Discuss the fundamental need for electronic processing in the context of a wide range of alternative and renewable resources. (4,7)

2. Give a historical perspective of energy conversion and the application of electronic circuits and devices to electrical conversion. (4, 7)

3. List and describe specific examples of useful electrical energy forms. Discuss implications of each in power electronics, and discuss how those aspects continue to grow in importance. (4, 7)

4. Analyze almost any two-switch power electronic circuit, and determine its input-output function, based on energy balance and energy conservation. (1)

5. Describe the constraints imposed by circuit theory on switch action, and discuss the physical bases of these constraints. (1)

6. Identify switch control waveforms appropriate for dc-dc conversion and for rectification, and plot output voltage or current waveforms for a converter circuit. (1, 2)

7. Analyze switching diode circuits, and determine input-output behavior and waveforms. (1, 2)

8. Use Fourier analysis to determine whether a converter or waveform can deliver energy to meet specified requirements and to analyze harmonic distortion. (1, 2)

9. Formulate and solve problems concerned with line and load regulation of power supplies. (1, 2)

10. Discuss user expectations and requirements, and describe the measures and specifications that have been developed to help users link needs to power supply performance. (4)

11. Design one- and two-element low-pass power filters. (2, 7)

12. Prepare designs based on ideal switches for single-stage and two-stage dc-dc converters. (1, 2, 7)

13. Discuss alternative energy applications and solid-state lighting, and the types of dc-dc converters applied in these contexts. (4)

B. By the time of Exam No. 2 (after about 30 lectures), the students should be able to do all of the items listed under A, plus the following:

14. Design rectifier-based power supplies to meet specified ripple and output power requirements, based on idealized control action. (1, 2, 7)

15. Identify switch control waveforms appropriate for controlled rectifiers and inverters, and plot input and output voltage and current waveforms for these converters. (1)

16. Analyze and design voltage-sourced inverters for power backup and alternative energy applications. (1, 2, 6)

17. Select the basic operating parameters, including modulation depth and voltage rail values, for pulse-width modulated inverters (PWM). (1, 2)

18. Discuss the important applications, and provide critical evaluation, of the most common types of dc-dc, ac-dc and dc-ac converters. (1, 3, 7)

19. Discuss and analyze PWM rectifier circuits. (1, 4)

20. List important current applications for inverters, and describe typical configurations for solar, electric vehicle, wind turbine, switching amplifier, and other inverter systems. (4)

C. By the time of the Final Exam (after about 43 lectures), the student should be able to do all of the items listed under A and B, plus the following:

21. Analyze dc-dc converters operating in the discontinuous conduction regime. (1)

22. Identify and compute critical inductance or capacitance values for dc-dc converters, or choose inductance and capacitance values based on critical energy considerations. (1, 2)

23. Develop and use static circuit models and interface circuits for realistic sources and loads, including batteries, motors, logic circuits, and others. (1, 2, 6)

24. Prepare estimates of the magnitudes and effects of stray wire inductance. (1, 2, 6)

25. Develop series L-C-R models of real capacitors, either from laboratory data, specification sheets, or engineering estimates. Select capacitors for a given power application, and compute the ripple effects of ESR. (1, 2, 6, 7)

26. Select appropriate wire sizes for a given application, and estimate regulation effects of wire resistance. (1, 2, 7)

27. Analyze magnetic circuits intended for application as power inductors or transformers in circuits operating at frequencies up to hundreds of kilohertz. (1)

28. Establish operating limits for magnetic devices based on saturation limits and loss considerations. (1, 2)

29. Analyze power converter effects of static voltage drops and resistances in semiconductors. (1)

30. Estimate losses in switching power semiconductors in specific converter circuits. (1)

31. Design open-loop dc-dc converters and rectifiers, with the characteristics of real semiconductor devices, energy storage devices, wires, sources, and loads taken into consideration. (1, 2, 4, 7)