基于比率一致性算法的孤岛微电网分布式二次频率控制

SECONDARY FREQUENCY CONTROL OF ISLANDED MICROGRIDS BASED ON RATIO CONSENSUE ALGORITHM

针对孤岛交流微电网的频率调节问题,考虑分布式电源(distributed generators,DG)间通信普遍存在延迟的实际情况,提出一种基于一致性算法的分布式二次控制策略。为降低因数据传输带来的能量消耗,采用事件触发的控制方式。该算法的显著特征在于能够在有限时间内收敛,以分布式的方式更新各电源的有功功率设定点,从而将平均频率误差驱动为零。与传统控制方法相比,所提策略仅需节点本身及邻居的信息即可实现控制目标,可提高系统的可靠性;采用基于事件触发的机制,进一步地降低对通信网络的依赖。最后在Matlab/Simulink的环境下构建含5台DG单元组成的孤岛交流微电网测试系统仿真模型,仿真结果验证了所提策略的有效性。

In order to solve the problem of frequency regulation in an islanded ac microgrid,considering the fact of communication delay among Distributed Generators(DGs),a distributed secondary control strategy based on consensus algorithm is proposed.In addition,the event-triggered control strategy is used to reduce the energy consumption of data transmission.The salient feature of the algorithm is that it can converge within a finite time and update the active power setpoint of each DG in a distributed manner,thus driving the average frequency error to zero.Compared with the traditional control method,the proposed distributed control strategy only needs to use the local and its neighbors’information to achieve the control objectives,which improves the reliability of the system.Based on the event trigger mechanism,it further reduces the dependence on the communication network.Finally,an islanded AC microgrid test system composed of five DG units is employed in MATLAB/Simulink to demonstrate the advantage and effectiveness of the proposed strategy.