Jian Sun

Dr. Jian Sun has more than two decades of experience in the modeling, analysis, and control of power-electronic converters and systems. His research focuses on understanding dynamic interactions in converter-based power systems and developing practical engineering methods for stability analysis and system design.

He is widely recognized for pioneering immittance-based frequency-domain methods, which have evolved into a comprehensive framework for modeling, analyzing, and designing converter-based power systems. These methods have been continuously refined through direct involvement in solving real-world stability problems for equipment manufacturers, utilities, technology companies, and system operators. His work has provided the foundation for and directly influenced the development of new converter control technologies, modeling and system study procedures, performance requirements, and industry standards across power electronics, power systems and data center industries.

This course reflects that evolution—from fundamental theory to practical engineering methodology.

The development of frequency-domain stability engineering has closely followed the rapid evolution of converter-based power systems over the past two decades. Each new generation of power systems introduced dynamic behaviors that existing engineering methods could not adequately explain, creating opportunities to develop new analytical tools and practical engineering procedures.

Dr. Sun’s research has focused on establishing a unified analytical framework for understanding dynamic interactions among converters, electrical machines, loads, and power systems. Major contributions include:

• Small-signal sequence immittance theory based on harmonic linearization
• Frequency-domain modeling of converter-interfaced resources
• Two-port and multi-port modeling of coupled AC/DC systems
• Stability analysis of AC and hybrid AC/DC power systems
• Stability-oriented engineering specifications
• Practical methods for root-cause diagnosis and mitigation

These contributions have helped establish frequency-domain methods as an important analytical framework for modern converter-based power systems.

The objective of this course is to develop engineering judgment in addition to analytical and quantitative skills.

Participants learn how to:

• develop meaningful frequency-domain models;
• interpret converter and system dynamics;
• identify the physical causes of instability;
• distinguish symptoms from root causes;
• formulate systematic engineering studies; and
• develop practical solutions applicable to real power systems.

Throughout the course, theoretical concepts are reinforced through engineering examples and case studies derived from actual industrial projects.