In order to constitute the resilient power system against disturbances including natural disaster, various new technologies for microgrid operations have been proposed recently. Although major Renewable Energy Sources (RESs) are usually connected to single-phase feeders, there exist few research works on single-phase microgrid operations. This paper investigates the realization of the single-phase microgrid by using Voltage Source Converters (VSCs) which are widely used to connect DC-base RES systems to conventional distribution feeders. We first study effective virtual inertia design in three-phase VSC in order to realize strong synchronizing operation as well as the enhancement of transient stability. Then, we propose a control framework for single-phase VSC, in which a new synchronizing mechanism that we call DC side measurement is developed. A governor and an Automatic Voltage Regulator (AVR) are also implemented into the controller to contribute to stable and reliable operation of the microgrid. It is shown that the independent use of the proposed VSC in each phase can also work successfully in a three-phase feeder. The effectiveness of the proposed method is verified in numerical simulations in single-phase and three-phase distribution systems where multiple VSCs are successfully operated in normal and islanding modes.
['Shinya Sekizaki', 'Yuki Nakamura', 'Yutaka Sasaki', 'Naoto Yorino', 'Yoshifumi Zoka', 'Ichiro Nishizaki']
A development of pseudo-synchronizing power VSCs controller for grid stabilization