基于分层控制的多微网并网/解列运行控制策略

摘要

To solve the problems of low control accuracy and frequency instability existing in the conventionalV/f droop control during the grid connection/disconnection process of microgrid,an improved V/δ droop control method considering the influence of equivalent resistance on microgrid control is proposed based on the theoretical analysis of droop control.Based on this method,a coordinated multi-microgrid hierarchical control system is designed by taking the microgrid central controller as the core.Then the transient-state control strategy and process during the grid connection/disconnection process of multi-microgrid is put forward.Finally,by taking an off-network wind/photovoltaic/diesel/energy-storage project as an example,the control strategy and the process are verified through the EMTDC/PSCAD simulation and the test in an actual system.%针对传统V/f 下垂控制在微网并网/孤岛运行过程中控制精度低、频率稳定性差等问题，通过对下垂控制的理论分析，考虑了线路等效电阻对微网控制的影响，提出了一种改进的 V/δ下垂控制方法。以此方法为基础，设计了以微网中央控制器为核心的多微网分层协调控制系统，提出了多微网并网/解列运行过程的暂态控制策略与流程。以某海岛离网型风光柴储系统为对象， EMTDC/PSCAD 仿真和实际系统试验验证了所提控制策略与流程的有效性。