基于电压跌落安全需求的直流微电网多端协同支撑技术  

Multi-terminal cooperative support technology for DC microgrid based on voltage drop safety demand

作　　者：张祥宇[1] 薛炎 付媛[1] ZHANG Xiangyu;XUE Yan;FU Yuan(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Baoding 071003,China)

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,河北保定071003

出　　处：《电力自动化设备》2024年第10期107-115,共9页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(52277100)。

摘　　要：量化直流电压稳定判据,在多端换流器协同下完成暂态电压支撑是直流微电网稳定运行的关键。根据直流微电网运行特性,分析功率波动、直流故障下系统运行点变化轨迹,获得系统具备暂态恢复能力下的直流电压跌落安全区间。基于直流微电网须遵循的等电量原则,根据电压跌落安全区间,计算系统允许放电电量,从而得到直流微电网量化稳定判据。在此基础上,利用交流主网、蓄电池、风机侧换流器的控制潜力,提出直流微电网的多端协同支撑技术,通过释放附加电量满足直流微电网在不同扰动下差异化的电压跌落安全需求,提升系统的暂态稳定裕度。搭建5端直流微电网仿真系统,验证所提控制策略对于直流电压的暂态支撑效果。Quantifying the DC voltage stability criterion and completing transient voltage support under the cooperation of multi-terminal converters are the keys to the stable operation of DC microgrid.According to the operation characteristics of DC microgrid,the change trajectory of the system operating point under power fluctuation and DC fault is analyzed,and the DC voltage drop safe range with the transient recovery capability is acquired.Based on the equal electric quantity principle to be followed by DC microgrid,the allowable discharge quantity of the system is calculated according to the voltage drop safe range,thereby the quantitative stability criterion of DC microgrid is obtained.On this basis,using the control potential of AC grid,battery and wind turbine side converters,the multi-terminal cooperative support technology of DC microgrid is proposed.By releasing additional electric quantity,the different voltage drop safety demands of DC microgrid under different disturbances are satisfied and the transient stability margin of the system is improved.A five-terminal DC microgrid simulation system is built to verify the transient support effect of the proposed control strategy on DC voltage.

关 键 词：直流微电网 暂态稳定分析 电压跌落安全区间 等电量原则 稳定判据 多端协同支撑技术 

分 类 号：TM721.1[电气工程—电力系统及自动化]