Flexible unbalanced control with peak current limitation for virtual synchronous generator under voltage sags

• 作者: Laijun CHEN Shengwei MEI Tianwen ZHENG Yan GUO
• 来源期刊: 现代电力系统与清洁能源学报(英文)
• 学科: 工学
• 关键词: VIRTUAL SYNCHRONOUS GENERATOR Unbalanced CONTROL Current REFERENCE GENERATOR Power REFERENCE GENERATOR Voltage sags
• 年，卷（期）: 2018,（1）
• 页码范围: 61-72
• 页数: 12页
• 分类号: TM341

摘要

Virtual synchronous generator(VSG)is gridfriendly for integrating distributed generations(DGs)since it can emulate the operation mechanism of traditional synchronous generator(SG).However,the traditional VSG control strategy,which is mainly suitable for balanced voltage conditions,may lead to power oscillations,current unbalance and even overcurrent under unbalanced voltage sags.To overcome this difficulty,a flexible unbalanced control with peak current limitation for VSG under unbalanced operating conditions is proposed.Based on the basic VSG control algorithm,the control strategy integrates two novel control modules,which are current reference generator(CRG)and power reference generator(PRG).The proposed control strategy can flexibly meet different operation demands,which includes current balancing,constant active or reactive power.And the injected currents are kept within safety values for a better utilization of the VSG power capacity.Furthermore,the experimental platform is built.Experimental results demonstrate the validness and effectiveness of the proposed control strategy.