| 引用本文: | 郑 涛,马 英,王珞秋,等.计及有功-频率环动态特性影响的储能VSG故障特性研究[J].电力系统保护与控制,2025,53(9):25-37.[点击复制] |
| ZHENG Tao,MA Ying,WANG Luoqiu,et al.Study on fault characteristics of energy storage VSG considering the dynamic characteristics of the active power-frequency loop[J].Power System Protection and Control,2025,53(9):25-37[点击复制] |
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| 摘要: |
| 储能虚拟同步发电机(virtual synchronous generator, VSG)技术是保障系统频率和电压稳定的重要举措。故障时功率的变化使有功-频率环输出角频率呈非线性变化特征，深刻影响储能VSG故障暂态特征。现有关于储能VSG故障特性的研究主要围绕放电状态展开，且忽略了角频率的变化，难以保证电压电流等电气量的解析精度。为此，对储能VSG在不同运行状态及运行状态快速切换时的电气量暂态特征展开研究，提出了一种计及有功-频率环动态特性影响的储能VSG故障特性解析方法。以对称短路为场景，首先分析了故障后角频率的变化机理，并提出了基于等面积原则的简化方法，阐明了角频率变化影响下电网电压的非线性变化特征。进一步，基于电网电压暂态特性对短路电流的影响路径，综合考虑无功-电压环和虚拟阻抗环的动态响应建立短路电流的解析表达式。相较于传统忽略有功-频率环动态特性的解析方法，所提方法准确刻画了储能VSG故障后电压电流等电气量故障暂态特征，所得结论可为构网型保护研究提供重要参考。 |
| 关键词: 储能虚拟同步发电机 有功-频率环 充放电运行状态 故障特性 对称短路 |
| DOI：10.19783/j.cnki.pspc.240557 |
| 投稿时间：2024-05-08修订日期：2024-10-29 |
| 基金项目:国家自然科学基金联合基金项目资助(U2166205)；国家电网有限公司科技项目资助(SGTYHT/21-JS-223)“电化学储能电站接入系统继电保护关键技术研究” |
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| Study on fault characteristics of energy storage VSG considering the dynamic characteristics of the active power-frequency loop |
| ZHENG Tao,MA Ying,WANG Luoqiu,MA Tongfang |
| (State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources
(North China Electric Power University), Beijing 102206, China) |
| Abstract: |
| The virtual synchronous generator (VSG) technology for energy storage is an important measure to ensure system frequency and voltage stability. During faults, power fluctuations cause nonlinear changes of the output angular frequency of the active power-frequency loop, significantly impacting the transient fault characteristics of energy storage VSG. Existing research on the fault characteristics of energy storage VSG mainly focuses on the discharging state and often neglects changes in angular frequency, making it difficult to ensure the accuracy of analytical calculations for electrical quantities such as voltage and current. To address this, this paper studies the transient characteristics of energy storage VSG in different operating states and during rapid switching of states. A new fault characteristic analysis method of energy storage VSG is proposed that takes into account the dynamic characteristics of the active power-frequency loop. Taking symmetrical short-circuit faults as the scenario, the mechanism of angular frequency variation after the fault is analyzed, and a simplified method based on the equal area principle is proposed to clarify the nonlinear characteristics of the grid voltage change under the influence of angular frequency changes. Furthermore, by analyzing how the transient characteristics of voltage affect the short-circuit current, the analytical expression of short-circuit current is established by comprehensively considering the dynamic response of the reactive power-voltage loop and the virtual impedance loop. Compared with traditional analytical methods that ignore the dynamic characteristics of the active power-frequency loop, the proposed method can accurately characterize the transient fault characteristics of electrical quantities such as voltage and current in energy storage VSG, while the conclusions can provide valuable references for protection strategy research in grid-forming scenarios. |
| Key words: energy storage virtual synchronous generator active power-frequency loop charge/discharge operating state fault characteristics symmetrical short circuit |
