【摘要】 虚拟同步发电机(virtual synchronous generator,VSG)型构网控制技术因其良好的阻尼与惯量支撑特性已被广泛关注，但其存在调频过程中难以抑制因工况、场景改变时控制性能弱化所导致的有功暂态超调、功率振荡等缺陷，调频能力适用度不足。该文首先在现有的VSG控制环节的基础上，通过理论推导建立了融合多控制环节的VSG调频小信号模型，在此基础上结合经典控制理论提出了VSG调频能力可行域的概念，用以定量表征和度量虚拟惯量、附加阻尼系数、电网强度等参数对VSG调频动态性能的影响。针对多工况、多场景下VSG调频性能无法兼顾以及控制参数不易整定的问题，提出了一种基于灵活调速控制的VSG调频能力提升策略。最后在PSCAD/EMTDC中构建仿真，并验证所提控制策略的有效性。更多还原

【Abstract】 VSG technology has been widely concerned because of its good damping and inertia support characteristics,but it is difficult to suppress the active power transient overshooting and power oscillation caused by the weakening of control performance when the working condition and scene change in the frequency modulation process. The frequency modulation capability is not suitable enough. Based on the existing VSG control units, this paper firstly establishes the VSG small signal model related to multiple control units through theoretical deduction. On this basis, the concept of VSG feasible domain of frequency modulation capability is proposed from aspect of classical control theory, and the influence of virtual inertia, additional damping coefficient,power grid strength and other parameters on VSG dynamic performance and feasible domain is quantitatively analyzed. In order to solve the problem that VSG frequency modulation performance can not be satisfied under different working conditions and scenarios at same time, a frequency modulation capability enhancement strategy based on virtual speed flexible regulation is proposed for extremely weak grid. Finally,simulation is constructed in PSCAD/EMTDC, and the effectiveness of the proposed control strategy is verified.更多还原