摘要
新能源和新负荷在现代电力系统中的渗透率日益提高,直流微电网在整合新能源和新负荷方面具有诸多优势,是未来智能配用电系统的重要组成部分。直流微电网系统内不存在无功控制与频率稳定等问题,母线电压是衡量系统供需功率是否平衡的首要指标。依据母线电压信号将系统运行划分为四个层级,在不同层级下母线电压由不同的电源维持稳定。母线电压在第一层至第三层时,电压波动范围较小由分布式电源维持母线电压稳定;电压在第四层级时,系统供需功率严重不平衡由交流电网维持母线电压稳定。依据各个分布式电源的发电特性,采用不同的控制技术实现分布式电源的合理出力。最后,建立直流微电网的MATLAB/Simulink仿真模型,仿真结果表明所提出的策略具有有效性和可行性。
In recent years,the penetration of new energy and new loads in modern power system is increasing.DC microgrid has many advantages in the integration of new energy and new loads and is an important component of the future intelligent power distribution system.There is no issue such as reactive power control or frequency stability in the DC microgrid system.The bus voltage is the principal criterion to estimate whether the active power of the system is balanced.According to the bus voltage signal,the operation of the system is divided into four layers and at different level,the bus voltage is maintained by different power supplies.The bus voltage is regulated by the distributed power supply in the case that the bus voltage is in the first layer to the third layer and with small voltage fluctuations.The adjustment of the DC bus voltage provided by the AC power grid is put into effect in the case that the bus voltage is in the fourth layer which means the DC bus voltage seriously deviates from the nominal value and the power supply and demand are serious imbalance.According to the characteristics of the distributed generation,different control technologies are adopted to realize reasonable output of the distributed power supply.Finally,the MATLAB/Simulink simulation model of the DC microgrid is established,and the simulation results verify that the proposed strategy is effective and feasible.
出处
《山东电力技术》
2017年第9期1-5,13,共6页
Shandong Electric Power
基金
国家自然科学基金项目(51407112)
关键词
直流微电网
功率平衡
电压分层
协调控制
下垂控制
DC microgrid
power balance
voltage hierarchy
coordination control
droop control