基于定子磁极局部磁场调制的定子永磁型无轴承磁通切换电机驱动系统的基础研究

Permanent magnets are inserted into the stator and every stator magnetic pole has two teeth with the opposite permanent magnet exciting direction for a flux-switching machine with permanent magnet in the stator.To achieve rotor being suspended at the radial direction, there are some problems such as lower suspension force and controlling levitation force relying on rotor position seriously because one tooth air gap magnetic field is increased while the other one is decreased for every stator magnetic pole if the classical rotor suspension force windings nested on every stator magnetic pole are applied.Thus, the main research include:1)The magnetic field distributing laws of stator magnetic pole air gap, the influence laws on the decuple operating for suspension force and torque ,and the optimal design rules of the bearingless machine with permanent magnets in the stator with the local magnetic field modulation.2)The decouple control strategy to compensate magnetic saturation for the drive of bearingless machine with permanent magnets inserted into stator.3)The compensating control strategy of some phases open fault tolerance for the drive of bearingless machine with permanent magnets in the stator.4)The efficiency optimal control strategy for the drive system of bearingless machine with permanent magnets inserted into stator.The research can provide some theoretical basis and technical support for the design and control of the drive system of bearingless machine with permanent magnets in the stator,and a new development ideal for machine drive applied in those applications of high speed, high temperature, pollution - free, high reliability, etc.

定子永磁型磁通切换电机将永磁体嵌放到定子上，每个定子磁极的两个齿中永磁激励磁场方向相反，若采用传统的定子磁极整体嵌套转子悬浮力控制绕组方案解决转子悬浮，会出现每个定子磁极的两个齿下气隙磁场一个增大、另一个减小的不利于最大悬浮力产生和严重依赖转子位置信息控制悬浮力等问题。为此，本项目主要研究：1）局部磁场调制定子永磁型无轴承电机定子磁极下的磁场分布规律，局部磁场调制对悬浮力和转矩的影响规律以及定子永磁型无轴承电机的优化设计准则。2）补偿磁路饱和的、消除转矩和悬浮力耦合的两种定子永磁型无轴承电机驱动系统解耦控制策略。3）定子永磁型无轴承电机缺相不平衡运行的补偿与解耦控制方法。4）定子永磁型无轴承电机效率最优理论和控制策略。通过本项目的研究，为定子永磁型无轴承电机驱动系统设计及其控制奠定坚实的理论和技术基础，为高速、高温、无污染、高可靠性等领域中电机驱动提供一种全新的发展思路。

本项目以无污染、高可靠性、高温等领域中有潜在应用价值的一种新型无轴承电机驱动系统为研究背景，研究了定子永磁型无轴承磁通切换电机优化设计及其驱动控制技术。.研究了局部磁场调制定子永磁型无轴承电机定子磁极下的磁场分布规律，局部磁场调制对悬浮力和转矩的影响规律。获得了无需转子位置角的悬浮绕组和需要转子位置角的悬浮绕组两种较佳构成方案。.采用定转子磁路分割、气隙磁路分割、定转子边界线判别等步骤，分析研究了转子无偏心时无轴承磁通切换电机变结构磁网络模型。基于此，提出一种考虑转子动态偏心的变结构磁网络模型，在此基础上对双绕组定子永磁型无轴承电机电磁特性及关键参数优化设计进行了创新性研究。.基于所提变结构磁网络模型，提出双绕组型电机悬浮力和转矩数学模型。采用补偿齿宽比对悬浮力的影响因数方法全面建立悬浮力数学模型；采用1/4电机磁网络模型推导建立转矩数学模型。基于此，提出双绕组无轴承电机转矩和悬浮力解耦的控制系统。.借助于定子单凸极模型、转子单凸极模型、傅里叶级数展开法，提出六相单绕组定子永磁型无轴承电机悬浮力和转矩精确数学模型。并基于此，提出单绕组电机转矩和悬浮力解耦的控制系统。.为了进一步提高电机旋转的可靠性，提出多相转矩绕组缺一相及缺多相时瞬时转矩控制策略。为了克服电机缺相后，剩余健康相数学模型不对称特性对电机瞬时转矩及瞬时磁场控制不利影响，采用虚拟变量定义法，重新构建出对称数学模型。.为了进一步减少多相转矩绕组无轴承电机驱动系统逆变桥臂个数，提高系统的可靠性，提出一种六相绕组和三相绕组串联运行控制系统。.为了进一步降低绕组损耗，从绕组产生最小铜损耗角度建立了多相电机悬浮电流分配控制策略。.分别设计并制作了低磁饱和和较高磁饱和的无轴电机样机，构建了基于DSP2812、DSP28377D的无轴承电机驱动系统试验平台，并进行了相关的试验研究。.研究成果有望为无轴承电机驱动技术提供一种全新的发展思路。