Differential electromagnetic saliency of a permanent magnet synchronous machine with concentrated winding and a short-circuited rotor winding

永磁同步电机应用广泛。使用永磁转子的主要优点是高功率和扭矩密度以及高动态性能。然而，一个基本的缺点是，转子位置总是需要磁场定向控制。该信息通常由位置传感器提供。这种位置传感器增加了总成本以及安装空间，特别是对于小型电机。考虑到高速度，位置信息包含在反电动势中。然而，在低速或静止时，必须应用主动位置检测方法来基于机器的位置相关的电磁特性来估计转子角。因此，在文献中，通常在工作点处的差分电感进行评估。然而，可以想象，使用另一个量进行无传感器位置估计可以产生更好的结果。此外，在文献中提出了一种称为环极电机的概念，它利用转子表面的短路绕组来影响差动电感。正如前面的项目所示，转子绕组也会影响差分高频电阻，由于与钢叠片中的涡流相互作用，差分高频电阻表现出很强的频率依赖性。该电阻凸极也被成功地用于无传感器位置估计。因此，本项目旨在通过使用优化的短路转子绕组来扩展无传感器控制的可行区域并使估计的位置误差最小化。作为第一步，一般考虑可用于位置估计的可能量。因此，必须从可测量的机器属性导出各种量，以调查是否可以通过使用替代估计量来改善转子位置估计的质量。之后，必须开发实验测试装置来研究涡流对线圈的有效HF阻抗的影响。此外，必须测量电工钢板中磁通位移的频率依赖性，以评估这种影响在常见的测试信号频率下是否可以忽略。根据测量结果，必须导出机器模型，通过该机器模型，可以识别针对给定机器产生最佳无传感器结果的估计量。对于这个数量，必须开发短路转子线圈的优化设计。最后，这个模型和优化过程必须通过实验测试装置来验证，以显示所导出的理论的潜力。

Permanent magnet synchronous machines are widely used. The main advantages that result from the use of a permanent magnet rotor are a high power and torque density as well as high dynamics. However, an essential drawback is that the rotor position is always required for field-oriented control. This information is generally provided by a position sensor. This positions sensor increases the overall costs as well as the installation space, especially for small motors. Motion sensorless control is therefore highly desirable.Considering high speed, the position information is contained in the back-EMF. However, at low speed or standstill active position detection methods must be applied to estimate the rotor angle based on the position-dependent electromagnetic properties of the machine. Therefore, in literature usually the differential inductances at the operating point are evaluated. However, it is imaginable that using another quantity for sensorless position estimation instead could yield even better results. Furthermore, in literatur a concept referred to as ringed-pole machine is proposed which uses a short-circuited winding on the rotor surface to influence the differential inductances. As could be shown in the preceding project, the rotor winding also affects the differential HF-resistance which shows a strong frequency-dependence due to the interaction with the eddy currents in the steel lamination. This resistive saliency was also successfully used for sensorless position estimation.Therefore this project aims to an extension of the feasible region for sensorless control and to a minimization of the estimated position error by the use of an optimized short-circuited rotor winding. Thereby, no restrictions are made regarding the quantity from which the position information is extracted.As a first step, possible quantities which can be used for the position estimation are considered in general. Thereby, various quantities have to be derived from the measurable machine properties to investigate if the quality of the rotor position estimation can be improved by the use of an alternative estimation quantity. Afterwards, an experimental test setup has to be developed to investigate the influence of eddy currents on the effective HF-impedance of a coil. Additionally, the frequency dependence of the flux displacement in the electrical steel sheet has to be measured to evaluate, if this effect is negligible at common test signal frequencies. From the measurement results a machine model has to be derived by which the estimation quantity that yields the best sensorless results for a given machine can be identified. For this quantity, an optimized design of the short-circuited rotor coil has to be developed. Finally, this model and the optimization procedure has to be verified by an experimental test setup to show the potential of the derived theory.