基于改进虚拟同步发电机算法的微网逆变器二次调频方案

发布时间：2018-04-30 05:22

本文选题：微电网 + 虚拟同步发电机　；参考：《电网技术》2017年08期

【摘要】：传统的虚拟同步发电机控制方案可帮助微网逆变器实现一次调频功能,为微网提供频率支撑,然而一次调频属于有差调节。通过改进虚拟同步发电机的控制结构,可使逆变器根据工作模式在一次调频和二次调频之间切换。二次调频适用于孤岛模式的微电网,可实现微网频率的无差控制,同时利用小信号等效以及根轨迹分析方法对二次调频控制策略进行了稳定性分析,并给出了相关参数的选取范围。该方案可使多台逆变器参与调频并按容量均分缺额功率,有利于总调频容量以及微电网容量的扩展。此外,二次调频对频率额定值的追踪功能还可辅助完成微网孤岛模式到并网模式的预同步环节,保证了预同步过程的顺利实行。最后,通过微网仿真平台验证了所提控制方案的有效性。
[Abstract]:The traditional control scheme of virtual synchronous generator can help the microgrid inverter to realize the primary frequency modulation function and provide frequency support for the microgrid. However, the primary frequency modulation is a differential regulation. By improving the control structure of the virtual synchronous generator, the inverter can switch between the primary frequency modulation and the secondary frequency modulation according to the working mode. The secondary frequency modulation is suitable for the isolated microgrid. The frequency of the microgrid can be controlled without difference. At the same time, the stability of the second frequency modulation control strategy is analyzed by using the method of small signal equivalence and root locus analysis. The selection range of related parameters is also given. This scheme enables multiple inverters to participate in FM and divide the missing power equally according to capacity, which is beneficial to the expansion of the total FM capacity and the capacity of microgrid. In addition, the tracking function of the frequency rating of the secondary frequency modulation can also help to complete the pre-synchronization between the isolated island mode and the grid-connected mode, which ensures the smooth implementation of the pre-synchronization process. Finally, the effectiveness of the proposed control scheme is verified by microgrid simulation platform.
【作者单位】：输配电装备及系统安全与新技术国家重点实验室(重庆大学);
【基金】：国家自然科学基金(51477021)~~
【分类号】：TM464;TM727

【参考文献】