Education within Electronic Power Grid

The group of Electronic Power Grid (eGrid) contribute to a wide range of courses, seminars, lectures and supervision across all semesters, however annually reoccurring the main contributions are

PhD courses

Grid-forming inverters: Principles and practices

Description: A Microgrid can be defined as a part of the grid with elements of prime energy movers, power electronics converters, distributed energy storage systems and local loads, that can operate autonomously but also interacting with main grid. The functionalities expected for these small grids are: black start operation, frequency and voltage stability, active and reactive power flow control, active power filter capabilities, and storage energy management. This way, the energy can be generated and stored near the consumption points, increasing the reliability and reducing the losses produced by the large power lines. In addition, as one of current trends and developments the Internet of Things (IoT) is affecting and will shape society and the world in all respects. The meet of IoT and energy industry naturally brings the promise of Energy Internet round the corner to introduce significant advantages and opportunities: enhanced automation, controllability, interoperability and energy efficiency, smarter energy management, and so on. The course starts giving some examples of Microgrids in the world. The course participants not only will learn modeling, simulation and control of three-phase voltage source inverters operating in grid-connected mode and islanded mode, but also, how these power electronics converters are integrated in AC Microgrids and how to be extended Energy Internet at a systemic level. 

Stability and control of grid-connected converters

Description: 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

Managing harmonics in modern power distribution networks

Description: The ever-increasing penetration of power-electronic-based sources and loads in power distribution networks poses new challenges to the quality of electricity supply. This course intends to provide a systematic discussing on the modeling, analysis and measurement of harmonics in modern power distribution systems. The theoretical modeling and analysis on the harmonic impacts of photovoltaic (PV) inverters in distribution systems will be introduced first. New developments and concepts in determining and assessing the harmonic emission limits and, in particular the supraharmonics above 2 kHz will then be reviewed. Next, practical aspects of harmonic measurements and the impedance identifications of network and devices will be discussed. Lastly, the system-level harmonic studies in low-voltage (LV) distribution networks with PV and electric vehicles (EVs) will be presented. Each aspect is illustrated by real world examples. The main topics to be covered include:

• Harmonic modeling and analysis of PV inverters considering the control impacts with different grid strengths
• Latest grid codes, standards and compliance assessment for power electronic-based devices
• Supraharmonics (2 kHz - 150 kHz): sources, mechanisms, propagation and resonances
• Harmonic measurement techniques and suitability of voltage and current transducers
• Frequency-dependent impedance measurement of LV distribution networks
• “Black-box” harmonic and impedance measurements of PV inverters and EVs
• Harmonic studies of LV distribution power networks due to PV and EVs

Ongoing PhD projects

• SiC-Based Active Damper for Stabilizing Power Electronic Based Power System (Yangwen Wang)
• Real-Time Impedance Identification and Control for Three-Phase Power Electronic Systems (Mengfan Zhang)
• Dynamic Interoperability of Grid-Forming Power Converters in Transmission Grids (Xinshuo Wang)
• Modeling and Control of Scalable Versatile Grid Emulation System (Zejie Li)
• Stability and Control of Multi-paralleled Single-phase Traction Converters (Liang Zhao)
• Stability and Reliable Operation of Wind Farm (Shiyi Liu)
• Coordinated Control and Protection of Wind Turbine Converters and Grid Interface (Guoqing Gao)

Completed PhD projects 

• Small-Signal and Transient Stability Analysis of Voltage-Source Converters (Heng Wu)
• Impedance Measurement and Estimation of Three-Phase Voltage-Source Converters (Hong Gong)
• Impedance Modeling and Stability Analysis of Grid-Interactive Converters (Yicheng Liao)