基于一致性的并联虚拟同步发电机分布式协同控制

Consensus-based distributed control for parallel-connected virtual synchronous generator

虚拟同步发电机(virtual synchronous generator,VSG)可模拟同步发电机运行机制,并为系统提供惯性和阻尼支撑.在孤岛模式下,VSG并联运行多采用分散下垂控制,不具备频率恢复以及有功出力合理分配等功能,为此,本文提出了一种基于一致性的并联VSG分布式控制方法,可改善系统频率与有功功率特性.本文首先介绍了传统VSG控制的数学模型,并在此基础上设计了VSG并联系统频率恢复及有功出力合理分配的整体方案.在分布式控制模式下,相邻VSG只需少量信息交互即可控制频率恢复到额定值,并可实现功率的按需分配,满足了不同用户的定制需求.仿真结果验证了所提方法的正确性和有效性.

Virtual synchronous generator(VSG)can mimic the operating mechanism of the synchronous generator,which can provide inertia and damping support for system.In islanded mode,parallel-connected VSGs mainly use decentralized droop control and the system is not able to restore frequency or reasonably share active power.To solve these problems,a distributed control strategy of parallel-connected VSGs based on consensus algorithm is proposed.The control strategy can improve the frequency and active power characteristics of the system.The mathematic model of traditional VSG control is firstly demonstrated.Based on that,the whole control scheme of frequency restoration and active power sharing for parallel-connected VSGs is established.With distributed control strategy,the scheme utilizes distributed communication network exchanging few information between neighbor VSGs to make the system restore frequency to nominal value and reasonably share active power to satisfy different demand.Simulation results verify the validity and effectiveness of the proposed control strategy.