具有惯量特性的并网逆变器黑箱模型辨识

针对具有惯量特性的并网逆变器,提出了一种统一虚拟同步发电机(VSG)模型和基于智能算法的惯量阻尼参数辨识方法,实现了对未知模型的商业化并网逆变器装置的数学建模和惯量评估.基于将具有惯量特性的并网逆变器装置等值为一台VSG的思想,总结了现有各种VSG的实现方法,归纳出一种包含锁相环和动稳态阻尼特性的统一VSG模型;利用遗传算法实现了统一VSG模型惯量和阻尼参数的准确辨识,但锁相环的控制参数却无法准确辨识,为此,从系统闭环极点的角度详细分析了锁相环参数辨识的准确性与其带宽之间的关系,并提出了选取高带宽锁相环的统一 VSG模型进行并网逆变器等值惯量和阻尼辨识的解决方案.最后,通过MATLAB/simulink仿真验证了所提模型辨识方法在多种不同VSG控制策略下的适用性和有效性.

Identification of black box model of grid-connected inverter with inertia characteristics

Aiming at the grid-connected inverter with inertia characteristics, a unified virtual synchronous generator (VSG) model and an inertia damping parameter identification method based on intelligent algorithms are proposed, which realizes the mathematical modeling and inertia evaluation of the commercial grid-connected inverter device of unknown model. Based on the idea that the grid-connected inverter device with inertia characteristics is equivalent to a VSG, the existing implementation methods of various VSGs are summarized, and a unified VSG model including phase-locked loop and dynamic and steady-state damping characteristics is summarized ; The genetic algorithm is used to realize the accurate identification of the inertia and damping parameters of the unified VSG model, but the control parameters of the phase-locked loop cannot be accurately identified. For this reason, the relationship between the accuracy of phase-locked loop parameter identification and its bandwidth is analyzed in detail from the perspective of the closed-loop pole of the system. And a solution is proposed to select the unified VSG model of the high-bandwidth phase-locked loop to identify the equivalent inertia and damping of the grid-connected inverter. Finally, the MATLAB/simulink simulation verifies the applicability and effectiveness of the proposed model identification method under a variety of different VSG control strategies.