双馈感应风力发电机系统中电流控制与转子转速控制时间尺度间跨时间尺度交互作用分析

Power electronics (PE) equipment contains multiple timescale energy storage components and control loops. As a result, the dynamic process presents multiple timescale characteristics in PE-dominated power systems. For simplicity, single timescale dynamics are often the focus of corresponding analysis, and the influence of different timescales (i.e., cross-timescale analysis) is rarely considered. However, there is an interaction effect between multiple timescale controls and energy storage components, which complicates system dynamics. In this study, the cross-timescale impact of current control on the dynamics of rotor speed control timescale are evaluated. First, based on a two-machine two-area system comprising a phase-locked loop (PLL)-synchronized doubly fed induction generator (DFIG)-based wind turbine (WT), the influence of the PLL on cross-timescale interactions is revealed via modal analysis. Then, a current control equivalent circuit is derived for analyzing its cross-timescale influence on rotor motion, and the LC resonance mechanism related to the current control is revealed. Moreover, the impact of the PLL on cross-timescale interactions is elucidated. Finally, the cross-timescale influence phenomena and mechanisms are verified via real-time digital simulations.