Sensorless Control of Permanent Magnet Synchronous Machines based on oversampling, FPGA based aquisition of measured currents - II

基于过采样、基于 FPGA 的测量电流采集的永磁同步电机无传感器控制 - II

• 批准号: 329209868
• 负责人: Professor Dr.-Ing. Axel Mertens
• 金额: --
• 依托单位: Institut für Antriebssysteme und Leistungselektronik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/329209868?language=en
• 关键词: Sensorless; Control; Permanent; Magnet; Synchronous

In the previous project, an encoderless, highly dynamic position and speed estimation for PMSM in the lower speed range including standstill was found and investigated, which allows a very good accuracy of the position estimation in the closed speed control loop and can also compensate for load torque changes in a highly dynamic manner. Only the inductance matrix of the machine is required for this. In contrast to most existing methods, the new method can also be parameterized analytically and does not require a large computational effort. The basis is an oversampling of the measured currents at a rate of approx. 106/s, which allows a precise analysis of the current waveforms over the duration of a PWM period. From this, the gradients of the currents, and thus the rate of change in flux, can be determined and compared with expected values based on the applied voltages. From the analytically available error function, a gradient can be determined according to the desired variable and calculated online with little effort. An online optimization of the error function in the manner of a gradient descent leads to the desired rotor position and speed within a sampling time. So far, however, this new approach could only be investigated with a small machine with surface magnets and almost linear behavior. In the follow-up project, an extension to heavily saturating machines is pursued, such as those typically used for higher power levels, e.g. in the field of traction. In such machines, saturation effects lead to operating ranges with vanishing or reversing anisotropies. In our own preparatory work, the procedure developed shows the potential of being able to operate within these areas when the mutual inductances are included in the models. Therefore, in the follow-up project, the developed procedure shall be extended for use with a higher-power machine with buried magnets, including operation in the regions with vanishing or reversed anisotropy. Side effects, such as currents distorted by eddy current effects or by long motor cables, must also be addressed. For an application in industrial drives, the current-dependent inductance matrix should also be able to be determined fully automatically and without a position sensor. Finally, the resulting procedure should be compared systematically with other processes according to the state of research in order to classify it in the existing body of knowledge.

在之前的项目中，发现并研究了PMSM在低速范围（包括静止）内的无编码器、高动态位置和速度估计，这使得在闭环速度控制回路中的位置估计具有非常好的精度，并且还可以以高动态方式补偿负载转矩变化。为此，仅需要机器的电感矩阵。与大多数现有的方法相比，新方法也可以解析地参数化，并且不需要大量的计算工作。其基础是以大约1000 Hz的速率对测得的电流进行过采样。106/s，这允许在PWM周期的持续时间内精确分析电流波形。由此，可以确定电流的梯度以及通量的变化率，并将其与基于所施加的电压的期望值进行比较。从分析上可用的误差函数，可以根据所需的变量确定梯度，并在线计算，几乎没有努力。以梯度下降的方式对误差函数进行在线优化，从而在采样时间内得到期望的转子位置和速度。然而，到目前为止，这种新方法只能用具有表面磁体和几乎线性行为的小型机器来研究。在后续项目中，将扩展到严重饱和的机器，例如通常用于更高功率水平的机器，例如在牵引领域。在这样的机器中，饱和效应导致各向异性消失或反转的操作范围。在我们自己的准备工作中，所开发的程序显示了当模型中包括互感时能够在这些区域内操作的潜力。因此，在后续项目中，应将开发的程序扩展到具有埋置磁体的更高功率机器，包括在各向异性消失或反转的区域中的操作。副作用，如涡流效应或长电机电缆造成的电流失真，也必须加以解决。对于工业驱动器中的应用，依赖于电流的电感矩阵也应该能够在没有位置传感器的情况下完全自动地确定。最后，应根据研究状况，将由此产生的程序与其他程序进行系统比较，以便将其归入现有知识体系。