The fault model of the inter-turn short circuit of the dry air-core reactor is first analysed in this study, by which an online monitoring method of the reactor inter-turn insulation fault is proposed by using the change of the power angle. In order to achieve high-precision measurement, the fundamental harmonic separation algorithm improved by Hanning windowed interpolation method can effectively reduce the error of power angle measurement caused by frequency fluctuation and harmonic interference. By comparing it with the power angle measurement errors of fast Fourier transform (FFT) and Hanning window interpolation FFT, the algorithm is verified. The sensitivity and stability of the equipment are verified by the experiment of simulating and eliminating the fault in the initial stage of the inter-turn short circuit. At the same time, an online monitoring system for inter-turn insulation fault of dry-type air-core reactor based on this method is designed, including field monitoring device, the intelligent electronic device of the dry air-core reactor and expert software. The method and monitoring device proposed in this study enables the fault to be accurately monitored in the early stage, which is of great significance for the safe operation of the reactor.

中文翻译：

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干式空芯电抗器匝间绝缘在线测量技术研究

本文首先分析了空芯电抗器匝间短路的故障模型，提出了利用功率角的变化对电抗器匝间绝缘故障进行在线监测的方法。为了实现高精度测量，汉宁加窗插值法改进了基波谐波分离算法，可以有效减少频率波动和谐波干扰引起的功率角测量误差。通过将其与快速傅立叶变换（FFT）和汉宁窗插值FFT的功率角测量误差进行比较，对该算法进行了验证。通过模拟和消除匝间短路初期故障的实验，验证了设备的灵敏度和稳定性。同时，设计了一种基于该方法的干式空心电抗器匝间绝缘故障在线监测系统，包括现场监测装置，干式空心电抗器智能电子装置和专家软件。本研究提出的方法和监测装置能够在早期阶段对故障进行准确监测，这对于反应堆的安全运行具有重要意义。