Enhancement of Dynamic Stiffness and Precision of Active Magnetic Bearings by Using Integrated Flux Density Measurement and Fast Switching Converter Topologies

通过使用集成磁通密度测量和快速开关转换器拓扑来增强主动磁力轴承的动态刚度和精度

基本信息

批准号：
221322256
负责人：
Professor Dr.-Ing. Wilfried Hofmann
金额：
--
依托单位：
Institut für Ionenstrahlphysik und Materialforschung
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2013
资助国家：
德国
起止时间：
2012-12-31 至 2019-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/221322256?language=en
关键词：
Enhancement Dynamic Stiffness Precision Active

项目摘要

Within the last years magnetic bearing technology has been pushed by a significant upturn in oil & gas industry as well as in machining applications. Nowadays, specific high speed spindles are equipped with industrially standardized active magnetic bearing systems (AMB) allowing for highly precise rotor positioning due to their contact-free and low-maintenance operation. However, compared to conventional ball bearings well-established AMB systems are limited by their relatively low stiffness. In order to improve dynamic performance flux based control algorithms have been suggested for the last decades already. The main challenge is how to integrate commercially available magnetic field sensors into the tiny air gap of typically 500 micro meter. Therefore, ultra-thin and preferably even flexible sensor elements meeting the strong requirements in lifetime and reliability are essentially needed. Within this project ultra-thin Bismuth Hall sensors with a total thickness of less than 150 micro meter are under development. After fabrication the sensor functionality and suitability for detection of time-varying magnetic fields in AMB systems are to be investigated intensely. Finally the sensor signal is intended to be used as directly integrated feedback for flux based AMB control strategies. Besides Hall sensorics precise rotor positioning strongly demands fast switching converters operated with high pulse frequencies (50 kHz) in order to achieve both accurate flux density/current control as well as a high bandwidth of the carrier frequency based position measurement system. Therefore, fast switching Gallium-Nitride-FETs (GaN) will be used for an H-bridge-converter powering the AMB coils. By using GaN-FETs a fast switching converter featuring substantially reduced dead times and low conduction losses can be realized.

在过去的几年中，磁性轴承技术已被石油和天然气行业以及加工应用的重大上涨推动。如今，特定的高速主轴配备了工业标准化的主动磁性轴承系统（AMB），由于其无接触性和低维护操作，因此可以高度精确的转子定位。但是，与传统的滚珠轴承相比，良好的AMB系统受其相对较低的刚度的限制。为了改善动态性能通量的控制算法，已经提出了过去几十年。主要的挑战是如何将市售的磁场传感器集成到通常500微米的微小气隙中。因此，基本上需要超薄且优选的灵活的传感器元素满足寿命和可靠性的强大要求。在这个项目中，正在开发总厚度小于150微米的超纯晶曲厅传感器。制造后，应深入研究AMB系统中检测时变磁场的传感器功能和适用性。最后，传感器信号旨在用作基于通量的AMB控制策略的直接集成反馈。除了霍尔传感器以外，精确的转子定位强烈要求快速切换转换器以高脉搏频率（50 kHz）运行，以实现准确的通量密度/电流控制以及基于载体频率的位置测量系统的高带宽。因此，快速开关二氮化甲酸-FET（GAN）将用于为AMB线圈提供动力的H桥连接器。通过使用GAN-FET，可以实现快速开关转换器，其快速转换器可以实现大幅减少的死亡时间和低传导损失。