基于共模电流的变频电机系统在线监测方法研究

The reliability of variable-frequency electric motor drive systems is crucial for its broad application, especially with the growing focus on reducing emission, enhance electrification and automation in industry. Online condition monitoring and fault prognostics techniques can effectively avoid serious failures, and enhance system reliability without the need of any major hardware modification. The goal of this project is to develop effective condition monitoring technology and effective automated control technique based on condition monitoring information. This would help control the electric motor drive system with consideration of the equipment's health condition, and therefore, enhance its reliability and prolong its useful life. This project first focuses on developing effective insulation condition monitoring and fault prognostics techniques, to build a condition monitoring system which can reflect the overall health condition of electric machine system. The project will then look into the aging and degradation of insulation material and extract health-related information from the monitored quantities and data. The condition monitoring system will be integrated into the control system to adjust control commands and operating regions of the machine based the health condition of the equipment and enhance the reliability of the overall electric machine systems. ..The novelty of this project is shown in the following: the project proposes a novel online condition monitoring and fault prognostics technique which can reflect the overall health condition of the electric machine system insulation; the condition monitoring and prognostics technique is then integrated into the control system to realize condition-based control of the electric machines to enhance its reliability.

电力传动设备的可靠性对我国的绿色化、电气化、智能化的工业规划非常关键。在线监测及故障预测技术，能有效避免严重故障的发生，从而在不做硬件改动的前提下提高系统的可靠性。因此，为了从根本上避免关键设备的严重故障，本项目针对变频传动系统，致力于开发能够反映绝缘系统整体健康状况，具有故障预测能力的可量化绝缘在线监测技术；基于该技术进行绝缘材料老化机理的研究并进行故障预测技术的可行性研究；将在线监测得到的系统健康状况信息直接用于变频器的控制算法中，实时调整变频电机的控制策略，形成一体化的在线监控系统，实现基于监测的实时控制，从而提高传动系统的可靠性。..本项目的创新性体现在提出了能够反映绝缘系统整体健康状况、具有故障预测能力的可量化绝缘在线监测方法；并基于该在线监测方法实现故障预测及电机控制相结合的一体化在线监测控制策略。

随着我国国民经济和国防建设的高速发展，高可靠性的电力传动系统显得尤为重要。在线监测及故障预测技术，能够对潜在的严重故障进行预警，在无需额外硬件的条件下实现非侵入式的监测，有效提高了系统的可靠性。本项目着眼于关键设备可靠性的提升，为变频传动系统整体绝缘健康状况开发可以实现绝缘健康状态量化评估和故障预警的技术方案。基于该技术对绝缘材料的老化机理和电机绕组绝缘模型进行了研究。为该监测技术研制了可以在大幅值的负荷电流干扰下精确测量微小绝缘漏电流的传感器，实验验证百安级负荷电流噪声中实现分侧、分相的高精度毫安级（负荷电流的0.001%）差分漏电流在线测量。利用所提出监测方法，可以充分利用变频器产生的多频率谐波，实现主绝缘、相间绝缘的区分监测，从而大大提高了绝缘监测的灵敏性。同时首次提出了最为薄弱的匝间绝缘老化状态在线监测算法，从而进一步提升了绝缘老化监测的有效性。利用在线监测得到的系统健康状况信息实时调整变频电机的控制策略，实现基于监测的实时控制，从而提高了传动系统的可靠性。本项目的创新性体现在提出了能够反映绝缘系统整体健康状况、具有故障预测能力的可量化绝缘在线监测方法；并基于该方法开发了相应的高精度漏电流传感器和实现了绝缘监测灵敏度和有效性的大幅提升。