Virtual control method applied to Modular Multilevel Converter

• DOI: 10.1016/j.egyr.2021.11.099
• Publication Date: 2021-11-26T13:57:06Z
• Authors: Zitao Zhang; Chuyang Wang; Yang Xu
• Keywords: Modular multilevel; Virtual inertia; 0202 electrical engineering, electronic engineering, information engineering; DC microgrid; Electrical engineering. Electronics. Nuclear engineering; 02 engineering and technology; DC transformer; 7. Clean energy; TK1-9971

The DC transformer based on the Modular Multilevel Converter (MMC) structure has advantages of robust scalability, low output voltage harmonic content, easy realization back-to-back connection, and high power transmission efficiency. It is widely used in distribution networks. However, traditional control methods hardly provide inertia for network, thereby reducing stability network when new energy fluctuations, failures, or other disturbances occur. Aiming at problem that bus easily affected by paper proposes a virtual method applied to with MMC structure. Similar introduction synchronous generators AC enhance system inertia, designs strategy dynamically adjusting capacitor added, which two-phase shift control. also presents calculation capacitance. When microgrid fluctuates significantly, can effectively suppress fluctuation bus. finally establishes model distributed sources PLECS simulation software, verifies effectiveness compared strategy.