考虑谐波电压的干式空心电抗器匝间短路早期故障诊断方法

An early fault diagnosis method for inter-turn short circuits in dry-type air-core reac⁃tors considering harmonic voltages

针对干式空心电抗器匝间短路早期故障特征不明显、电力系统中谐波含量波动影响诊断准确率等问题,提出了考虑谐波电压影响的干式空心电抗器匝间短路故障特征分析与诊断方法。针对电抗器正常运行、早期匝间电弧性短路、中后期匝间金属熔接性短路等3种工况,通过分析串/并联电抗器故障工况运行特性,分别确定串/并联电抗器匝间短路早期故障特征量。建立考虑谐波电压的电抗器匝间短路故障仿真模型,分析多工况下串/并联电抗器电气特征量的变化规律,提出基于电流谐波比的串联电抗器匝间短路故障诊断方法,及基于有功功率比的并联电抗器匝间短路故障诊断方法。搭建串/并电抗器匝间故障试验平台,通过试验验证了所提方法的正确性和有效性。

In response to challenges such as the subtle early fault indications and the fluctuating harmonic content in power systems affecting diagnostic accuracy,this paper presents a novel method for analyzing and diagnosing inter-turn short circuit faults in dry-type air-core reactors,taking into consideration the influence of harmonic volt⁃ages.Addressing three distinct operating conditions such as normal reactor operation,early-stage arc-type inter-turn short circuits,and mid-to-late-stage metal fusion-type inter-turn short circuits,the paper analyzes the operational characteristics of both series and parallel reactors under fault conditions to identify specific early fault indicators for inter-turn short circuits in each configuration.Additionally,the paper establishes a simulation model for inter-turn short circuit faults in reactors that accounts for harmonic voltage effects and analyzes the variation in electrical char⁃acteristics of series and parallel reactors under various operating conditions.Subsequently,it proposes a diagnostic method based on the current harmonic ratio for series reactor faults and another method based on the active power ra⁃tio for parallel reactor faults.To validate the effectiveness of the proposed method,the paper constructs an experi⁃mental test platform for inter-turn faults in series and parallel reactors and conducts experiments to confirm its cor⁃rectness and efficacy.