基于统一电压电流预测的微电网多模控制方法

Multi-mode Operation Method of Microgrid Based on Unified Voltage and Current Predictive Control

传统微电网控制系统多采用分层控制技术架构,在解决有约束多目标优化问题时灵活性和智能化水平受限。模型预测控制(MPC)通过对微电网未来运行状态预测,并设计计及多目标和约束条件的价值函数在线滚动优化,可有效解决上述问题。然而,受限于孤岛和并网模式下微电网控制目标差异性,不同模式切换时MPC价值函数需发生较大改变,此时微电网系统存在暂态冲击和稳定性降低等一系列问题。为此,提出一种基于统一电压电流预测控制(UVCPC)的微电网多模运行控制方法,首先在建立微电网统一离散预测模型基础上,设计多模式一致性价值函数,并引入分布式协同二次控制,实现分层架构下微电网控制。最后,搭建20 kW多分布式电源(DG)并联微电网测试样机对所提方法进行验证分析,与传统MPC技术相比,该方法克服了多价值函数下系统暂态冲击等问题,且无需集中控制,具有运行高效、可靠性高等优势。

The traditional microgrid control system mainly adopts hierarchical control technology architecture,which has limited flexibility and intelligence level when solving constrained multi-objective optimization problems.Model predictive control(MPC)can effectively solve the above problems by predicting the future operation state of the microgrid and designing the online rolling optimization of the value function considering multi-objective and constraint conditions.However,due to the differences in control objectives of microgrid under islanded and grid-connected modes,MPC value function needs to be changed greatly when different modes are switched.In this case,the microgrid system has a series of problems such as transient impact and stability reduction.Therefore,a multi-mode operation control method of microgrid based on unified voltage and current predictive control(UVCPC)is proposed.Firstly,a unified discrete prediction model for microgrid is established,a multi-mode consistent value function is designed,and then distributed cooperative quadratic control is introduced to realize microgrid control under hierarchical architecture.Finally,a test prototype of 20 kW multi-distributed generator(DG)parallel microgrid is built to verify and analyze the proposed method.Compared with the traditional MPC technology,the proposed method overcomes the problems such as transient impact of the system under multi-value functions,without centralized control,and has the advantages of efficient operation and high reliability.