基于VSG的无PLL光储并网预同步控制策略  

Pre-synchronization Control Strategy for PLL Free Optical Storage VSG Grid-connected

作　　者：沈志雨 董哲 李佼洁 SHEN Zhiyu;DONG Zhe;LI Jiaojie(School of Electronic Information,Xi′an Polytechnic University,Xi′an 710048,China)

机构地区：[1]西安工程大学电子信息学院,陕西西安710048

出　　处：《电工技术》2022年第8期46-49,158,共5页Electric Engineering

基　　金：国家自然科学基金资助(编号52007138)。

摘　　要：针对光储虚拟同步发电机(Virtual Synchronous Generator,VSG)微网系统在含锁相环模块的传统预同步控制方式下,其离/并网过程中容易出现电压电流畸变,导致系统不能平滑切换等问题,提出了一种基于相角补偿的无锁相环(PLL)的VSG离/并网预同步控制策略,利用VSG可自动生成相位参考的特性,对电网电压的相位和幅值进行同步追踪来抑制冲击电流,实现频率、电压调节。该预同步策略不但简化了并网预同步控制过程,还可避免因锁相环精度和响应速度的影响而引起的并网逆变器-电网交互系统的稳定性问题,并保证系统的离/并网平滑快速切换。最后仿真验证了该预同步策略的有效性。For the optical storage virtual synchronous generator(VSG)microgrid system,under the traditional pre-synchronization control mode with phase-locked loop module,voltage and current distortions are prone to occur during the off/grid process,resulting in the system not being able to switch smoothly,etc.Problem.A VSG off/grid pre-synchronization control strategy without phase-locked loop(PLL)based on phase angle compensation is proposed.Using the characteristic that VSG can automatically generate phase reference,the phase and amplitude of grid voltage are tracked synchronously to suppress impulse current and realize frequency and voltage regulation.The pre-synchronization strategy not only simplifies the pre synchronization control process of grid connection,but also avoids the stability problem of grid connected inverter grid interactive system caused by the influence of PLL accuracy and response speed,and ensures the smooth and fast off/grid switching of the system.Finally,the effectiveness of the pre synchronization strategy is verified by simulation.

关 键 词：虚拟同步发电机 并网预同步 离/并网切换 无锁相环控制 

分 类 号：TM743[电气工程—电力系统及自动化]