论文标题
统一的虚拟振荡器控制，用于网格形成和网格的转换器
Unified Virtual Oscillator Control for Grid-Forming and Grid-Following Converters
论文作者
论文摘要
提出了一个统一的虚拟振荡器控制器（UVOC），该控制器可以为网格形成（GFM）和网格 - 围绕（GFL）电压源转换器（VSC）提供统一的分析，设计和实现框架。基于振荡器的GFM控制器，例如可调度的虚拟振荡器控制（DVOC），提供了严格的分析框架，具有增强的同步，但缺乏有效的故障处理能力，从而严重限制了实际应用。提出的UVOC促进了与任意低的网格电压和快速流动限制的同步。与现有的GFM控制器不同，这通常可以在故障期间切换到备用控制器。在连接的网格和岛上的模式下，具有UVOC的GFM操作都可以在两者之间进行无缝过渡。在GFL转换器中，双向功率流控制和DC总线电压调节是通过UVOC实现的。对于弱网格应用中，与PLL相关的同步问题，GFL或GFM操作不需要相锁环（PLL）。详细的GFM和GFL操作的小信号模型已开发出来，并提供了控制器参数的系统设计指南。通过混合AC-DC微电网中的硬件实验对所提出的控制器进行了验证。
A unified virtual oscillator controller (uVOC) is proposed, which enables a unified analysis, design, and implementation framework for both grid-forming (GFM) and grid-following (GFL) voltage source converters (VSCs). Oscillator based GFM controllers, such as dispatchable virtual oscillator control (dVOC), offer rigorous analytical framework with enhanced synchronization, but lack effective fault handling capability which severely limits practical application. The proposed uVOC facilitates synchronization with an arbitrarily low grid voltage and fast over-current limiting; this enables effective fault ride-through unlike existing GFM controllers which typically switch to a back-up controller during fault. GFM operation with uVOC is achieved in both grid connected and islanded modes with seamless transition between the two. In GFL converters, bidirectional power flow control and DC bus voltage regulation is achieved with uVOC. No phase-locked-loop (PLL) is required for either GFL or GFM operation circumventing the synchronization issues associated with PLLs in weak grid applications. Detail small signal models for GFM and GFL operation have been developed and systematic design guidelines for controller parameters are provided. The proposed controller is validated through hardware experiments in a hybrid AC-DC microgrid.
