【作者】 庄恒建；

【导师】 刘万顺；

【作者基本信息】 华北电力大学（北京） ， 电力系统及其自动化， 2003， 硕士

【摘要】 变压器主保护选择差动在原理上存在不足，带来的问题就是如何准确鉴别励磁涌流与内部故障，这也是目前变压器保护的难点。本文分析了现有的励磁涌流识别判据，认为，在基于电流波形的判据中，改进型波形相关法的性能最优；指出了基于磁通特性、励磁电感的判据存在的不足，针对“等效瞬时电感变化量方法”的局限性，提出了改进的措施。同时，提出了“基于等效瞬时电感分布特性识别励磁涌流的新方法”。为克服差动原理的先天不足，提出了“基于改进型序阻抗原理的变压器保护方案”。为了分析和验证理论研究的成果，用VC++集成开发环境开发了可以模拟硬件装置的软件测试平台，为微机保护的理论研究和装置开发提供了一种方便快捷的工具。更多还原

【Abstract】 How to discriminate between internal fault and magnetizing inrush current is the difficulty of transformer protection when apply differential relay.The exiting criterions to discriminate between internal fault and magnetizing inrush current were analyzed and the conclusion is: the performance of improved correlation algorithm is superior to the others in criterions based on wave-form. A new scheme named “new method to discriminate between internal fault and magnetizing inrush based on distribution of equivalent instantaneous inductance” is put forward in order to compensate the disadvantage of “method based on the change of equivalent instantaneous inductance”. In order to overcome the innate shortage, “Transformer protective scheme based on the improved sequence impedance algorithm” is bring forward in this paper.The software test platform which can simulate hardware relay device is developed based on the VC++ IDE for the sake of analysis and validation of new scheme.更多还原