This paper analyses the impact of square wave pulse voltage deadtime on the partial discharge (PD) and the lifetime of turn-to-turn insulation. A bipolar repetitive pulse voltage with a deadtime of 0–10 μs is produced using double half-bridge solid-state switches having push–pull technology controlled by a field-programmable gate array. The mechanism of the discharge process at rising and falling edges of the pulse voltage before and after deadtime is analysed in detail. The discharge amplitude and PD probability at the rising/falling edges of the voltage waveform increase as the deadtime increases from 0 to 10 μs due to the remanent charges. The number of PD and their intensity is higher at the first rising/falling edges of pulse voltage as compared to the second rising/falling edges for all deadtimes 0–10 μs. As the deadtime increases beyond 2 μs, the number of PDs increases and concentrates at a specific phase angle of rising/falling edges. These localise discharges degrade the insulation material and reduce its lifetime. This study helps to identify the inverter-fed motor insulation faults due to deadtime. It can provide guidelines to motor insulation designers to determine the limit value of deadtime to compensate PD and ensure the safer operation of such motors.

中文翻译：

---

脉宽调制电压源死区时间对变频电机绝缘局部放电和寿命的影响

本文分析了方波脉冲电压死区时间对局部放电（PD）和匝间绝缘寿命的影响。使用双半桥固态开关产生死区时间为 0–10 μs 的双极重复脉冲电压，该开关具有由现场可编程门阵列控制的推挽技术。详细分析了死区前后脉冲电压上升沿和下降沿的放电过程机理。由于剩余电荷，随着死区时间从 0 增加到 10 μs，电压波形上升/下降沿处的放电幅度和 PD 概率增加。对于所有死区时间 0–10 μs，与第二个上升/下降沿相比，脉冲电压的第一个上升/下降沿的 PD 数量及其强度更高。随着死区时间增加超过 2 μs，PD 的数量增加并集中在上升沿/下降沿的特定相位角处。这些局部放电会降低绝缘材料的性能并缩短其使用寿命。这项研究有助于识别因死区时间导致的变频电机绝缘故障。它可以为电机绝缘设计人员提供指南，以确定死区时间的极限值以补偿 PD 并确保此类电机的安全运行。