摘要
【目的】随着新能源占比的持续提升,基于锁相环同步的传统跟网型控制在弱电网条件下逐渐暴露出稳定性不足的缺陷,具备自主同步源特性的构网型控制逐步成为热点解决方案,但当前研究大多聚焦于其电压或同步稳定特性,较少关注其频率调节能力和特性。【方法】本文概述了下垂控制、虚拟同步机控制、匹配控制和虚拟振荡器控制这4种主流构网型控制方式的发展进程和调频控制原理,并从控制环路、适用场景等方面分析了以上方式的优势与不足。在此基础上,构建了新能源并网仿真模型,模拟分析了不同调频控制在多样化场景下的调频响应特性,总结了构网型控制在策略优化、参数整定和多机协同等方面所面临的挑战,并对其发展趋势进行了展望。【结果】下垂控制通过响应系统频率偏差调节机组有功功率,具有结构简单、电网强度适应性强的优点,但该控制方式缺乏惯量支撑,调频性能相对较弱;虚拟同步机控制在下垂控制的基础上,模拟了传统同步机的惯量响应特性,能更好地抑制系统频率变化性能,但面临参数整定、故障穿越和多机协同等挑战;匹配控制以直流电容的动态特性模拟传统同步机惯量特性,抑制了系统频率变化性能,但难以在频率暂稳态区间长期为系统提供支撑;虚拟振荡器控制因幅值和频率由振荡器动态方程直接生成,调频响应类似下垂控制,但输出谐波含量较高难以满足并网要求。【结论】虚拟同步机控制在参与系统调频中凭借其兼顾调频性能和电网强度适应性的技术优势,成为构网型控制中最具前景的研究方向,但需要突破同步稳定、故障穿越和协同控制等技术难题。未来应针对控制策略与参数优化、多机协同控制等方面进行深化研究,进而推动构网型控制的规模化应用。
[Objective]With the increasing proportion of new energy,traditional grid-following(GFL)control based on phase-locked loop(PLL)synchronization gradually exhibits inherent stability limitations in weak grid conditions.Meanwhile,grid-forming(GFM)control with self-synchronizing source characteristics has emerged as a hot solution.However,existing research predominantly focuses on the voltage regulation or synchronization stability of GFM control,with less attention to its frequency modulation capability and characteristics.[Methods]This paper systematically reviewed four mainstream GFM control methods,including droop control,virtual synchronous generator(VSG)control,matching control,and virtual oscillator control(VOC),explained their frequency modulation principles,and analyzed their advantages and disadvantages from the aspects of the control loop and application scenarios.On this basis,a grid-connected simulation model for new energy systems was built to conduct a simulation-based analysis of the frequency modulation response characteristics of different kinds of frequency modulation control across diverse scenarios.Finally,this study summarized challenges of GFM control in strategy optimization,parameter tuning,and multi-unit coordination,with the future development prospects pointed out.[Results]Droop control regulates the active power of generating units by responding to system frequency deviations,featuring advantages of the simple structure and strong grid strength adaptability.However,its lack of inertia support results in relatively weaker frequency modulation performance.On the basis of droop control,VSG control simulates the inertia response characteristics of conventional synchronous machines and can better suppress the change performance of system frequency.However,it faces challenges in parameter tuning,fault ride-through,and multi-unit coordination.Matching control utilizes the dynamic characteristics of DC capacitors to simulate the inertia properties of traditional synchronous machines and thus restrain change performance of system frequency,but it fails to provide sustained support in the frequency quasi-steady state.VOC generates frequency responses similar to droop control via oscillator dynamic equations that directly govern amplitude and frequency.However,it is difficult for its high output harmonics to satisfy grid connection requirements.[Conclusion]Virtual synchronous machine control has become the most promising research direction in GFM control due to its technical advantages of balancing frequency modulation performance and strong grid strength adaptability in participating in system frequency modulation.However,technical challenges including synchronization stability,fault ride-through,and coordinated control need to be tackled.In the future,in-depth research should be conducted on control strategies and parameter optimization,and multi-unit collaborated control to facilitate the large-scale application of GFM control.
作者
李卫星
潘韵同
马欣彤
晁璞璞
孙广宇
金泳霖
LI Weixing;PAN Yuntong;MA Xintong;CHAO Pupu;SUN Guangyu;JIN Yonglin(School of Electrical Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China;Electric Power Research Institute,State Grid Liaoning Electric Power Supply Co.,Ltd.,Shenyang 110006,Liaoning,China)
出处
《沈阳工业大学学报》
北大核心
2025年第5期545-557,共13页
Journal of Shenyang University of Technology
基金
国网辽宁省电力有限公司科技项目(2023ZX-18)。
关键词
新能源
构网型
调频控制
下垂控制
虚拟同步机控制
匹配控制
虚拟振荡器控制
new energy
grid-forming
frequency modulation control
droop control
virtual synchronous generator control
matching control
virtual oscillator control
