论文标题
在不对称网格故障期间基于逆变器的发电的同步不稳定性
Synchronization Instability of Inverter-Based Generation During Asymmetrical Grid Faults
论文作者
论文摘要
传统电力系统的瞬时稳定性涉及发电机与网络的正序电压保持同步的能力，无论是用于对称或不对称断层的能力。相反，在不对称故障下，基于逆变器的发电（IBG）都应关注正序和负同步。这是因为最新的网格代码规定，IBG在不对称故障上骑行时应注入双序电流。目前，关于不对称断层期间的同步稳定性知之甚少。由于耦合的双序列同步涉及，这与仅积极序列同步明显不同。本文旨在填补这一空白。考虑到不对称断层下的序列耦合，开发了IBG的双序列同步模型。基于该模型，确定稳态平衡点应鉴定出的条件。条件揭示了可能的同步不稳定性的类型，包括积极序列主导的不稳定性和负序列占主导地位。对于不同类型的不稳定性，定量分析了主要因素，这反映了当前注入幅度的极限。超过限制将导致正同步和负序列同步的丧失。模拟和分析通过模拟和硬件实验验证。
The transient stability of traditional power systems is concerned with the ability of generators to stay synchronized with the positive-sequence voltage of the network, whether for symmetrical or asymmetrical faults. In contrast, both positive- and negative-sequence synchronizations should be of concern for inverter-based generation (IBG) under asymmetrical faults. This is because the latest grid codes stipulate that IBG should inject dual-sequence current when riding through asymmetrical faults. Currently, much less is known about the synchronization stability during asymmetrical faults. This significantly differs from the positive-sequence synchronization alone because the coupled dual-sequence synchronization is involved. This paper aims to fill this gap. Considering the sequence coupling under asymmetrical faults, the dual-sequence synchronization model of IBG is developed. Based on the model, the conditions that steady-state equilibrium points should follow are identified. The conditions throw light on the possible types of synchronization instability, including the positive-sequence dominated instability and the negative-sequence dominated one. For different types of instability, the dominant factors are analyzed quantitatively, which are reflected by the limit on the current injection amplitude. Exceeding the limit will lead to the loss of both positive- and negative-sequence synchronizations. The model and the analysis are verified by simulations and hardware-in-the-loop experiments.
