The harmonic state-space (HSS), the dynamic phasor (DP), and the generalized dq (GDQ) modeling are three widely used methods for small-signal analysis of ac power electronic systems. By reviewing their principles and deriving their mathematical relationships, this paper proposes a unified framework for all the three approaches. The unified modeling reveals that the linearization and transformation can be exchanged flexibly in the modeling process, and the initial phase takes a role in transforming the GDQ model into the HSS or DP model. Case studies on a three-phase voltage-source converter in unbalanced power grids are provided for validation. The relationships of three modeling methods are verified by mathematical proofs and time-domain simulations. The unified frequency-domain model is further validated through the frequency scan in experiments. Insights of the unified modeling framework and recommendations from engineering perspectives are finally discussed.

中文翻译：

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交流电力电子系统的小信号建模：批判性回顾和统一建模


谐波状态空间 (HSS)、动态相量 (DP) 和广义 dq (GDQ) 建模是交流电力电子系统小信号分析中广泛使用的三种方法。通过回顾它们的原理并推导它们的数学关系，本文为所有三种方法提出了一个统一的框架。统一建模揭示了建模过程中线性化和变换可以灵活互换，初始阶段起到将GDQ模型转化为HSS或DP模型的作用。提供了不平衡电网中三相电压源换流器的案例研究以进行验证。通过数学证明和时域仿真验证了三种建模方法的关系。通过实验中的频率扫描进一步验证了统一频域模型。最后讨论了统一建模框架的见解和工程角度的建议。