非平稳工况下感应电机匝间短路与高阻连接诊断

Diagnosis of Inter-Turn Short Circuits and High-Resistance Connections for Induction Motors Under Non-Stationary Conditions

摘要:

匝间短路（ITSC）和高阻连接（HRC）是常见的定子故障，及时检测出故障可防止更严重的电机损伤，提高工业设施的可靠性和安全性。然而，这两种故障特征相似容易造成误判，在非平稳工况下检测指标波动较大，且故障相位识别需同步采集多类型信号增加了检测成本。为解决上述问题，提出一种仅采用电压信号实现非平稳工况下ITSC、HRC检测与相位识别的方法。首先，建立故障模型并开展机理分析，提取能够有效区分ITSC和HRC的故障特征。其次，基于变分模态分解算法估计信号瞬时频率脊线，构建零序电压因子、负序电压因子，减小工况波动对检测指标的影响。最后，利用电压信号相位构建相位识别指标。通过感应电机故障模拟实验台验证所提方法的有效性。结果表明，所提方法在非平稳工况下可有效检测ITSC、HRC故障并识别相位，且不需借助转速计和电流传感器。

Abstract:

Inter-turn short circuits （ITSC） and high-resistance connections （HRC） are common faults in stators， and detecting them in a timely manner is crucial to prevent severe motor damage and improve the reliability and safety of industrial facilities. However， the fault characteristics of ITSC and HRC are similar， which easily leads to misjudgment. Additionally， detection indicators can fluctuate under non-stationary conditions， and accurately identifying faulty phases requires the synchronous acquisition of multiple types of signals， which increases the cost of detection. To address these problems， this study proposes a method that uses only voltage signals to detect and differentiate between ITSC and HRC faults under non-stationary conditions. First， fault models are established， and a mechanism analysis is conducted to extract fault features that can effectively distinguish between ITSC and HRC. Next， the variational mode decomposition （VMD） algorithm is used to estimate the instantaneous frequency ridge of the signal. Then， the zero-sequence voltage factor （ZVF） and negative-sequence voltage factor （NVF） are constructed to minimize the influence of non-stationary conditions. Finally， a phase identification indicator is created based on the phase of voltage signals. The effectiveness of the proposed method is validated on an induction motor experimental platform. The results demonstrate that the proposed method can accurately detect ITSC and HRC faults and identify the corresponding phase under non-stationary conditions without the need for a tachometer or current sensor.