In order to implement brushless DC machine (BLDCM) servo system in a high-temperature hostile environment, a novel electromagnetic BLDCM rotor position sensor is put forward. Concentrated excitation windings are symmetrically mounted at the middle of the stator inner circumference notches and the detection ones were wound around the stator teeth. The rotor cylinder outer surface is cut to form sunken right-angled sectors at the corresponding positions of the magnetic S poles on the machine rotor. With the magnetic field excited by a relatively high frequency sinusoidal current, the detected signals are modulated by the machine rotor position, as the total mutual inductance between one detection windings and all the excitation ones varies as a function of the sensor rotor position. As all magnetic iron cores are laminated from new soft magnetic alloy ultra-thin sheet, the excitation current frequency may be increase to 100kHz. Moreover a linear model and an equivalent-magnetic-circuit model are set up and based on the later, the sensor geometry parameters are optimized by a simulated annealing algorithm. A finite element analysis is done in ANSYS software program and an experiment system is also built up. Both the simulation and the experimenal results reveal the validity and reliability of the whole scheme.%为了在高温等恶劣环境中实现无刷直流电机(BLDCM)的伺服控制,提出了一种基于电磁原理的新型BLDCM转子位置传感器.传感器激励用集中绕组对称地安放在定子槽的中心位置,检测用集中绕组密绕在定子齿上,转子外圆周表面设计有与电机N极和S极位置对应的凸起和凹陷.实际工作时,以正弦交流电作为励磁载波,单个检测绕组和激励绕组间的总互感是转子位置角的函数,通过对检测绕组中感应调幅波的监测即可实现转子位置的检测.传感器定子、转子铁心均由新型软磁合金薄片堆叠而成,励磁载波的频率可提升至100kHz.建立了传感器的线性模型和等效磁网络模型,并以后者为基础利用模拟退火算法对系统的结构参数进行了优化.利用ANSYS软件对传感器进行了有限元分析,并设计了相应的试验系统.仿真和试验结果验证了整体设计方案的正确性和有效性.
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