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Events at Department of Energy Technology

Industrial/PhD Course: Modeling and Control of Grid-Connected Converters


27.05.2020 kl. 08.30 - 29.05.2020 kl. 16.00



Professor Xiongfei Wang


Prof. Lennart Harnefors, ABB Corporate Research/KTH, Sweden
Prof. Xiongfei Wang, Aalborg University, Denmark



Grid-connected converters have commonly been used with renewable power generations, flexible ac/dc power transmission systems, regenerative drives, etc. As the increasing use of converters in electrical grids, the dynamic modeling and control of converters become critical for building a stable power-electronic-based power system. This course thus devotes to provide a design-oriented analysis on the control dynamics of grid-connected converters, covering the fundamental and state-of-the-art of modeling, stability analysis and control topics, including:  

  • Vector current control
  • Complex-valued frequency-domain modeling
  • Impedance-based stability analysis
  • Grid synchronization control and its stability impact
  • DC-link and ac-bus voltage control
  • Robust damping control techniques

Day 1: Vector Current Control, Prof. Xiongfei Wang (3 hours), Prof. Lennart Harnefors (3 hours)

  • Space vectors and coordinate transformation
  • Small-signal modeling of converter power stage
  • Design of vector current controller and its anti-windup
  • Influences of time delay and LCL-filter resonance
  • Harmonic current control and practical design

Day 2: Grid Synchronization and Power Control, Prof. Lennart Harnefors (3 hours), Prof. Xiongfei Wang (3 hours)

  • Phase-Locked Loop (PLL): small-signal modeling and parameter tuning
  • Influence of PLL on grid-converter interactions
  • Impedance-based modeling and stability analysis
  • Stability of DC-link Voltage Control (DVC)
  • Stability of AC-bus Voltage Control (AVC)

Day 3: Robust Damping Control, Prof. Xiongfei Wang (3 hours), Prof. Lennart Harnefors (3 hours)

  • Virtual impedance control
  • Passivity-based current control
  • Power-synchronization control  
  • Step-by-step design cases


Prior knowledge of three-phase systems, power electronics fundamentals, feedback control theory are preferred.  

Form of evaluation

Exercises and report




6000 DKK for PhD students outside of Denmark and 8000 DKK for the Industry.


Department of Energy Technology


Aalborg University, Pontoppidanstræde 101, room 1.015, 9220 Aalborg East