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对高频频段进行评估,以对功率变压器的故障进行分类
Karl Schiewaldt1, Bruno Albuquerque de Castro1, Jorge Alfredo Ardila-Rey2
1School of Engineering, Bauru, Department of Electrical Engineering, São Paulo State University (UNESP), Bauru 17033-360, SP, Brazil.
Sensors (Basel, Switzerland)
|August 10, 2024
概括
超高频 (UHF) 传感有效地分类功率变压器故障,即使在降低频段. 主要组件分析 (PCA) 显示了具有成本效益的绝缘监控系统的前景.
科学领域:
- 电气工程 电气工程
- 材料科学 材料科学 材料科学
- 状态监控 状态监控
背景情况:
- 超高频 (UHF) 传感对于检测功率变压器绝缘中的部分放电 (PD) 是至关重要的.
- 对于准确的故障诊断的最佳超高频频段存在不确定性.
- 减少带宽可能会影响基于频率的故障分类系统的性能.
研究的目的:
- 评估频谱带限制对功率变压器故障分类的影响.
- 根据UHF信号频率内容评估信号处理技术的有效性.
- 调查使用降低频段用于成本效益高的数据采集的可行性.
主要方法:
- 分析了三种功率变压器的运行条件 (健康,电弧,口PDs).
- 三个自组织地图 (色技术,PCA,SACT) 用于故障分类.
- 在三个频段中分析了UHF信号的频率内容:全频谱,100 MHz-1 GHz和400 MHz-900 MHz.
主要成果:
- 降低的频率范围并没有显著影响变压器运行条件的分类.
- 400MHz-900MHz频段在故障分类方面被证明是有效的.
- 主要组件分析 (PCA) 在评估的技术中显示出最有前途的结果.
结论:
- 较低的超高频频段,如400 MHz-900 MHz,对于功率变压器故障分类是可行的.
- 可以开发减少带宽的监控系统,从而节省成本.
- PCA是基于UHF的变压器状态监测的强大技术,即使频率数据有限.
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