摘要
固态变压器(SST)具备交直流环节,可用于实现交、直流微电网间的互联。针对交-直-交非隔离型的SST,提出引入直流下垂控制环节的虚拟同步电机(VSM)控制策略,使SST交直流端口具备惯性和阻尼,提升系统稳定性;建立VSM小信号模型分析直流侧电压与功率分配关系,便于实现交、直流侧互联微电网间的能量平衡,进而提出基于VSM的SST整体控制策略,在SST网侧和源荷侧变换器级联新的控制环路,实现网侧变换器快速响应及源荷侧变换器单/三相负荷、多控制类型(恒功率控制、下垂控制、虚拟同步机控制)三相分布式电源接入的需求;通过仿真分析验证所提基于VSM控制的SST对不同控制类型分布式电源的接入适应性。
SST(Solid State Transformer)has both AC and DC links,which can be utilized to facilitate the interconnection between AC and DC microgrids.As for AC-DC-AC non-isolated SST,a VSM(Virtual Synchronous Machine)control strategy with DC droop control link is proposed,which makes AC and DC terminals of SST have inertia and damping,so as to improve the system stability.Then,the small-signal model of VSM is established to analyze the distribution relationship between the DC-side voltage and power,which is convenient to realize the power balance between AC and DC side interconnected microgrids.Furthermore,the VSM-based control strategy of SST is developed.Meanwhile,new control loops are cascaded to converters at SST’s grid-side and source load-side to enable the fast response ability of grid-side converters.Additionally,the requirement to integrate single-phase or three-phase demands,three-phase distributed generations with multiple types of control(constant power control,droop control and virtual synchronous generator control)of the source load-side converter is satisfied.Simulative results verify the adaptability of the proposed VSMbased control strategy of SST when distributed generations are integrated with multiple control types.
作者
李振
吕志鹏
盛万兴
杜松怀
李鹏华
LI Zhen;Lü Zhipeng;SHENG Wanxing;DU Songhuai;LI Penghua(College of Information and Electrical Engineering,China Agricultural University,Beijing 100083,China;Power Distribution Research Institute,China Electric Power Research Institute,Beijing 100192,China)
出处
《电力自动化设备》
EI
CSCD
北大核心
2020年第9期80-87,共8页
Electric Power Automation Equipment
基金
国家电网公司上海能源互联网研究院研究项目(5442SH190003)。
关键词
固态变压器
虚拟同步电机控制
直流下垂控制
小信号模型
分布式电源
solid state transformer
virtual synchronous machine control
DC droop control
small-signal model
distributed power generation
