Complementary Tutorial for Workshop Attendees:
From Frequency Scan to Immittance-Based Stability Theory

Date

Tuesday, October 8, 2024
morning: 10:00–12:00 am
Room: BALTICA

Venue

This complementary tutorial will be held at the workshop venue, the Scandic Marina Congress Center.

Please come to the main registration desk to collect your conference badge before going to the tutorial.

We are pleased to offer to the 2024 Workshop attendees this complementary tutorial as an introduction to the training course “Immittance-Based Frequency-Domain Stability Analysis and Design of Converter-Interfaced Resources and Systems” (https://immittance-methods.net/). The 2nd edition of this course is scheduled to start in January 2025 and is now open for early-bird registration.

Frequency scan and screening has been used to identify subsynchronous resonance involving generators and, in recent years, wind turbines. The method is easy to use but for many years remained an ad hoc numerical procedure for a few isolated applications. That changed with the establishment of small-signal sequence immittance theory, of which frequency scan is a special routine. The more rigorous definition and development have led to a general framework and many practical methods to address new stability challenges in renewable energy, HVDC transmission, and future power systems.

This tutorial gives an overview of the immittance-based stability theory and highlights a few applications that demonstrate its utility, practicality, and advantages. The tutorial also gives a preview of the training course and will be presented by the course instructor, Dr. Jian Sun who is credited for establishing much of the framework of immittance-based stability theory and promoting its applications in different industries internationally. Dr. Sun will also be available during the workshop to discuss questions related to the training course.

  • The tutorial is free of charge for 2024 Wind and Solar Integration Workshop attendees but requires registration to help us with planning.
  • To register, simply log into your account on the online registration platform and complete the separate registration form found in the left-side menu.

Background and Objectives

The term immittance, combining the concept of impedance and admittance, was created by Hendrik W. Bode. Input and output immittances of a converter are a type of transfer functions that define the converter’s frequency response to external disturbances. Immittance modeling and analysis of converters in ac power systems was initially motivated by the need to study converter-based power system stability for electric ship and more-electric aircraft development.

The rapid development of renewable energy and HVDC transmission in recent years created an opportunity as well as a need to apply the methods to utility power grids. As a result, a large body of knowledge and a wealth of practical experiences have been developed. Immittance-based frequency-domain modeling now provides a comprehensive framework to study the stability of inverter-based resources (IBRs) and systems.

It also enables design engineers to optimize IBRs and their control design for stable operation with/in the grid. New immittance-based IBR performance specifications and system study procedures/tools are also being developed.

 

Tutorial Lecturer

Dr. Jian Sun
Professor, Department of ECSE
Rensselaer Polytechnic Institute
Troy, NY, USA

Dr. Jian Sun is a Professor at Rensselaer Polytechnic Institute located in Troy, New York, USA. An expert in power electronics and power systems, Dr. Sun is credited for establishing the small-signal sequence immittance theory and developing it into a systematic framework for requency-domain modeling, stability analysis, and control of power electronics in power systems.

He also contributed greatly to practical applications of his theory through research collaboration with industry as well as direct involvement in solving real-world stability problems in renewable energy, HVDC transmission, and converter-based power distribution systems.

He has consulted for TenneT, China State Grid, GE, Facebook and other companies in that capacity. The materials presented in the course are developed from his firsthand expertise, insights, and practical experiences accumulated over 15 years.