RESEARCH FOR MINITUARIZATION AND POWER EFFICIENCY IMPROVEMENT OF MAGNETICALLY SUSPENDED MOTOR FOR ARTIFICIAL HEART

本课题的研究目的是建立小型、大功率、高效的人工心脏用磁悬浮电机。研究了三种类型的磁悬浮电机。径向悬浮电机是一种将转子沿径向悬浮的电机，是一种用于人工心脏磁悬浮泵的基础研究。研制的磁悬浮泵最大转速为2400 rpm，最大扬程压力为310 mmHg，最大流量为10 l /min。血浆游离血红蛋白为13 mg/dl，溶血性能与人工心脏相当低。研究了在上下定子之间设置悬浮转子并沿轴向悬浮的轴向悬浮电机，以明确五自由度控制悬浮电机的基本特性。在电机上增加径向控制机构，构造五自由度控制悬浮电机。成功研制了转速可达3200rpm的五自由度控制悬浮电机，建立了五自由度控制悬浮电机的基本设计方法。研制了一种用于轴流泵的五自由度微型磁悬浮电机。叶轮由叶轮两侧的一组混合磁轴承悬浮。电机定子设置在磁轴承之间。悬挂电机的长度为92 mm，直径为48 mm。在10000转/分的转速下，最大扭矩超过10毫微米。在空中完全悬浮的最大旋转速度为16,000 rpm。在使用条件下，总功耗为12w，足以植入。研制成功了用于轴流人工心脏的微型悬浮电机。

Purpose of this research project is to establish small and high power efficient magnetic suspended motors for artificial heart. Three type of magnetic suspended motor have been studied.1.Radially suspended motor, which suspends the rotor in the radial direction, has been studied for a fundamental research of a maglev pump for an artificial heart. The maximum rotating speed, the maximum head pressure, and the maximum flow rate of the developed maglev pump were 2400 rpm, 310 mmHg, and 10 L./min, respectively. The plasma free hemoglobin was 13 mg/dl and the hemolysis property was enough low as an artificial heart.2.Axially suspended motor, that a levitated rotor is set between top and bottom stators and suspended in the axial direction, has been studied to clear basic characteristics of a suspended motor with control in five degrees of freedom (5-DOF). The radial control mechanism was added to this motor and the 5-DOF control suspended motor was constructed. The 5-DOF control suspended motor, which can rotate up to 3200 rpm, has been developed successfully and a basic design method of the 5-DOF control suspended motor was established.3.A miniaturized magnetic suspended motor with 5-DOF control has been developed for an axial flow pump. An impeller is suspended by a set of hybrid magnetic bearings at each side of the impeller. The motor stator is set between the magnetic bearings. The length and diameter of the suspended motor is 92 mm, 48 mm, respectively. Maximum torque is over 10 mNm under a rotational speed of 10000 rpm. Maximum rotating sp0eed with complete levitation in the air was 16,000 rpm. The total power consumption in the usage condition was 12 W and enough low for implantation. The micro suspended motor for an axial flow artificial heart has been developed successfully.