Flexible Virtual Synchronous Generator Control for Distributed Generator with Adaptive Inertia

Abstract

Distributed generators using power electronic converter interface have no inherent inertial response similar to that from the rotating mass of conventional synchronous generators. Virtual synchronous generator (VSG) emulates the behavior of the synchronous generator including system inertia to improve system dynamic performance. Unlike a real synchronous generator, using VSG with proper design, the equivalent inertia of the distributed generator can be controlled in a wider range. In this paper, a flexible virtual synchronous generator (FVSG) control strategy is proposed, with adaptive inertia contributing to a fast and smooth inertial response. The frequency change rate is designed as an adaptive inertia coefficient to flexibly accommodate system inertia with frequency fluctuation rate. Compared with the conventional VSG control, based on fixed inertia coefficient, both inertia support and oscillation suppression are achieved in the proposed control scheme. Moreover, the principles of control parameters design are analyzed in details. Thus, the dynamic response of the system frequency can be substantially improved by the FVSG. Both Matlab/Simulink simulations and prototype tests are implemented to validate the proposed FVSG control strategy on improving system dynamic frequency performance.

Keywords:

• micro grid
• distributed generator
• virtual synchronous generator (VSG)
• adaptive inertia
• frequency support

Acknowledgement

The authors gratefully acknowledge the support of National Natural Science Foundation of China (no. 51807064) and the Natural Science Foundation of Hebei Province (no. E2018502152).

Additional information

Notes on contributors

Jianhui Meng

Jianhui Meng received the B.Sc. degree in electrical engineering and automation from the North University of China, Taiyuan, China, in 2008, and the M.Sc. degree in power electronics and power drives from Dalian Jiaotong University, Dalian, China, in 2011, and the Ph.D. degree in electrical engineering from North China Electric Power University, Beijing, China, in 2015. He is currently an Engineer with the School of Electrical and Electronic Engineering, North China Electric Power University. His research interests include inverter control for distributed generator and the application of power electronic technology in power system.

Yi Wang

Yi Wang received the B.Sc. and Ph. D degrees in electrical engineering from North China Electric Power University, China, in 1999 and 2005, respectively. He is currently a Professor in the School of Electrical and Electronic Engineering, North China Electric Power University. His research interests include the control of wind power integration and DC grids.

Jialin Peng

Jialin Peng received the B.Sc. degree in electrical engineering and automation from the Agricultural University of Hebei, Baoding, China, in 2017. She is currently working toward the M.Sc. degree in North China Electric Power University. Her research interests include inverter control for distributed generator and the control technology of virtual synchronous generator.

Lie Xu

Lie Xu received the B.Sc. degree in mechatronics from Zhejiang University, Hangzhou, China, in 1993, and the Ph.D. degree in electrical engineering from the University of Sheffield, Sheffield, UK, in 2000. He is currently a Professor at the Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK. He previously worked in Queen's University of Belfast and ALSTOM T&D, Stafford, UK. His research interests include power electronics, wind energy generation and grid integration, and application of power electronics to power distribution and transmission.

Jun Yin

Jun Yin received the B.Eng. degree in electrical engineering from Zhengzhou University of Light Industry, Zhengzhou, China, in 2008, and the Ph.D. degree in power system and automation from North China Electric Power University, Beijing, China, in 2016.He is currently an Assistant Professor at North China University of Water Resources and Electric Power. His research interests include renewable energy and power system security and control.