双馈感应发电机(doubly fed induction generator,DFIG)装设电力系统稳定器(power system stabilizer,PSS),有助于抑制同步发电机间功角振荡,但抑制效果受DFIG锁相环(phase-locked loop,PLL)跟踪误差影响.考虑PSS与PLL耦合特性对功角振荡的影响,提出改善振荡抑制效果的DFIG控制参数协调优化算法.首先基于DFIG有功控制的分解等效结构绘制DFIG-PSS与锁相误差的耦合路径,提出耦合特性解析表达.然后建立耦合解析表达对控制参数的轨迹灵敏度向量,以向量2-范数之比定义耦合强度,量化耦合特性对功角振荡的影响程度.最后基于耦合强度指标,提出带有PLL参数动态不等式约束的多步优化模型,以协调DFIG控制参数取值,提高并网系统对功角振荡的抑制效果.仿真结果证实了耦合特性对功角振荡的影响,验证了所提协调优化算法的有效性.
Coordinated Optimization to Control Parameters of DFIG Considering Influence of Coupling Between DFIG-PSS and PLL on Power Angle Oscillations
The doubly fed induction generator (DFIG) may damp the power angle oscillations between synchronous generators with the power system stabilizer (PSS), whereas, the DFIG phase-locked loop (PLL) tracking error will influ-ence the suppression effect on oscillations. The influence of coupling behaviors of PSS and PLL on power angle oscillations is considered in this paper, and the coordinated optimization method to control parameters of the DFIG is newly proposed to improve the suppression effect. Firstly, the coupling path containing the DFIG-PSS and phase-locking error is drawn with the detached equivalent structure of DFIG active control, and the coupling function of the two actions is proposed. Then the trajectory sensitivity vectors of coupling function to control parameters is established, while the coupling strength is defined based on the proportion of the vector 2-norms, quantifying the degree to which the coupling characteristic influence the power angle oscillations. Finally, the multi-step optimization model containing the dynamic inequality constraints to PLL is proposed with the coupling strength indicators, which is used to adjust the control param-eters of the DFIG and improve the suppression effect on power angle oscillation. The simulation results verify the influence of the coupling characteristics on the power angle oscillation and the effectiveness of the proposed coordinated optimization method.
power angle oscillationdoubly-fed induction generationpower system stabilizerphase-locked loop (PLL)coupling characteristicsmulti-step coordinated optimization
万方数据
维普
