Stability Analysis and Control of AC / DC Hybrid Power System with High Proportion of Power Electronics



With the continuous expansion of the scale of renewable energy, the application of renewable energy has a trend from grid connection to self-connecting, working as a mircogrid. Both AC microgrid and DC microgrid have advantage in power applications. Many renewable energy sources generate power in direct current and many electrical loads like electric vehicles and data centers use DC power. DC microgrid can transfer power without changing current form repeatedly which means more efficiency and less operational cost. While AC microgrid can effectively integrate with traditional power grids. Therefore, AC / DC hybrid power system is an important direction of power system in the future.
The AC / DC hybrid microgrid characterized by high penetration of renewable energy has high proportion of power electronic devices. Thus, the system shows different characteristics from the traditional power system. Because DC part of system has no inertia. It has a fast response speed. However, that will cause system stability problem like sub-/super-synchronous oscillations. Besides, unreasonable control of system AC part may affect the stable operation of the main grid which is unacceptable.
This project aims to solve the stability analysis and control problems of high proportion power electronic AC / DC hybrid power system. This project will start from the establishment of a system impedance model to describe the operating state of system. And propose online system impedance detection method. Combining stability impedance criterion with system impedance detection results, a real-time system stability analysis method executed by converter can be proposed. The output of converter will change actively based on system stability analysis results. So, the system will have controlled damping in short term dynamic process and controlled output impedance in long term. The robustness of the system will be improved.

Funding: CSC Scholarship
Effektiv start/slut dato01/12/202130/11/2024


Udforsk forskningsemnerne, som dette projekt berører. Disse etiketter er oprettet på grundlag af de underliggende bevillinger/legater. Sammen danner de et unikt fingerprint.