| 引用本文: | 戴志辉,韦舒清,柳梅元.基于电压矢量重构的光伏场站送出线路距离保护方案[J].电力自动化设备,2025,45(7):35-42 |
| DAI Zhihui,WEI Shuqing,LIU Meiyuan.Distance protection scheme for transmission line of PV power station based on voltage vector reconstruction[J].Electric Power Automation Equipment,2025,45(7):35-42 |
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| 摘要: |
| 针对大规模新能源经交流联络线送出场景下新能源侧工频变化量距离保护性能劣化的问题，提出一种适用于新能源接入的电压矢量重构新型距离保护方案。在电压矢量重构策略的配合下，保护背侧阻抗在故障期间能够表现出恒定阻抗角，使整定电压和故障电压的相对大小始终能正确反映整定点与故障点的位置关系。在此基础上，利用发生区内、外故障时保护动作量的差异形成故障识别判据。所提方案不受新能源出力特性和并网无功支撑要求的影响，相较于现有保护原理具有更优的灵敏性、可靠性。仿真结果表明，所提保护方案能够在2个工频周期内准确识别区内、外故障，且具有较高耐过渡电阻的能力。 |
| 关键词: 光伏场站 弱馈性 交流联络线 距离保护 短路阻抗 |
| DOI：10.16081/j.epae.202505001 |
| 分类号:TM77 |
| 基金项目:国家自然科学基金资助项目(51877084) |
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| Distance protection scheme for transmission line of PV power station based on voltage vector reconstruction |
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DAI Zhihui, WEI Shuqing, LIU Meiyuan
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Hebei Laboratory of Distributed Energy Storage and Microgrid, North China Electric Power University, Baoding 071003, China
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| Abstract: |
| Targeting the issue of performance degradation of power frequency variation distance protection at the new energy side under the scenario of large-scale new energy delivering through AC tie lines, a novel distance protection scheme based on voltage vector reconstruction for new energy access is proposed. With the voltage vector reconstruction strategy, the back-end impedance of protection presents a constant sequence angle during faults, so that the relative value of the setting voltage and the fault voltage can always correctly reflect the position relationship between the setting point and the fault point. On this basis, the fault identification criterion is formed by using the difference of the protection operation quantities under internal and external faults. The proposed scheme is not influenced by the characteristics of new energy output or reactive power support requirements for grid connection, and has superior sensitivity and reliability in comparison to the existing protection principles. The simulative results show that the proposed protection scheme is capable of accurately identifying internal and external faults within two fundamental frequency cycles, and has high tolerance ability against transient resistance. |
| Key words: PV power station weak-infeed property AC transmission lines distance protection short circuit impedance |
