【作者】 黄雷；

【导师】 赵光宙；

【作者基本信息】 浙江大学 ， 电力电子与电力传动， 2008， 博士

【摘要】 永磁型无轴承电机系统的无传感器运行,是永磁型无轴承电机研究中需要探索的新命题,这对无轴承电机实现低成本、实用化的研究具有重要实际意义。本文进行了适合于无传感器运行的永磁型无轴承电机结构设计研究,建立了永磁型无轴承电机的悬浮力模型及其控制系统。为构成五自由度悬浮系统,研究了永磁偏置径/轴向电磁轴承的设计与控制。针对永磁型无轴承电机的无位置/速度传感器的运行及无径向位移传感器运行进行了深入的理论研究及实验验证。论文主要工作包括:一、分析了永磁型无轴承电机的基本工作原理。对永磁型无轴承电机的本体设计进行了研究,提出了永磁体内插式转子结构的无轴承电机方案,其性能满足悬浮运行与控制要求,还为研究无位置、无位移传感器运行创造了条件。建立了计及转子凸极影响和定、转子定位偏心的磁悬浮力解析模型,深入分析了悬浮力模型中有关参数的获取机理,并通过有限元磁场分析方法实现了可控悬浮力和单边磁拉力计算中的计及饱和、电枢反应和悬浮中定、转子定位偏心等非线性因素的参数提取。二、基于扩展磁路法建立了永磁偏置径/轴向电磁轴承的精确数学模型,依据此模型进行了电磁轴承的设计并得到了电流刚度和位移刚度等控制参数。设计了一种性能优良的双向三电平PWM开关功放,实现了永磁偏置径/轴向电磁轴承的悬浮系统运行。三、建立了由永磁型无轴承电机与永磁偏置径/轴向电磁轴承构成的五自由度悬浮系统的转子动力学模型。为提高永磁型无轴承电机的悬浮性能,采用混合灵敏度的H∞鲁棒控制方法设计了悬浮力系统控制器。研究结果表明,所设计的控制器性能优良,对外部扰动等不确定因素有很好的鲁棒性。四、提出了高速下采用自适应滑模观测器法和低速下采用脉动高频信号注入法的转子位置自检测复合方法,以实现永磁型无轴承电机无位置传感器运行。该方法在低速采用高频信号注入法确保了转子位置和速度的检测精度,高速采用自适应滑模观测器方法保证了系统响应的快速性及对参数变化的鲁棒性。确定了两种方法平滑切换的原则。仿真和实验研究表明,转子位置自检测复合方法能够在全速范围内有效检测出转子的空间位置和速度,实现无传感器方式的稳定悬浮运行。随后提出了利用转矩绕组和悬浮绕组的互感,仅在转矩绕组上注入高频激励信号以同时实现转子径向位移信号和位置/速度信号提取的新方法。通过理论分析和电磁场计算证明,该方法能有效地检测转子的位置/速度和位移信号,并能精确地实现位移检测出信号在水平、垂直方向的解耦。五、设计了基于TMS320F2812数字信号处理器的全数字控制系统,该控制系统为实现永磁型无轴承电机系统无传感器运行研究提供了可靠的实验条件。更多还原

【Abstract】 The sensorless operation of the permanent magnet-type bearingless motor(PMBLM) to realize the highly integration of the motor and sensor is a new research topic, which will meet the requirement of low cost and practical application of the bearingless motors.This dissertation focuses mainly on the sensoless operation of the PMBLM, including the motor design of the PMBLM, the development of the mathematical model of the levitation force, the robust control of the levitation system. The design and control of a three degree-of-freedom permanent magnet biased radial-axial magnetic bearing was also introduced to form a five degree-of-freedom levitation system. The position/speed sensorless operation and the displacement sensorless operation of the PMBLM were studied theoretically and experimentally.In this dissertation the design of PMBLM was introduced based on the principle of PMBLM operation. An inset-type permanent magnet rotor which has the concept of integration of the motor and self-sensing was proposed to enhance radial suspension force generation and to generate the saliency needed during the signal injection method for sensorless operation. A relatively accurate analytical expression of the magnetic levitation force for the PMBLM was proposed with the eccentricity of stator and rotor taken into consideration. As the parameter of the levitation force model is the key to control the suspension force and realize the stable suspension operation, the extraction principle of the key parameter was studied in detail, and realized by using the finite element method.Based on the extended magnetic circuit theory, the mathematical model of the permanent magnet biased radial-axial magnetic bearing was deduced and a prototype magnetic bearing was designed according to this model. The coefficients of current stiffness and displacement stiffness were also deduced. A three level PWM amplifier was proposed in this paper to reduce the current ripple and to achieve the successful suspension of the magnetic bearing.The dynamical model of the five degree-of-freedom rotor supported by the PMBLM and the radial-axial magnetic bearing was then deduced. An H∞robust controller was proposed to improve the suspension characteristic of the PMBLM. Result show that the performances of the proposed controller were superior to those of the traditional PID controller in the aspect of being robust to model uncertainties and disturbances.A novel rotor position and speed estimation scheme using the combined rotor position self-sensing method was suggested, which will meet the need of sensorless operation of the PMBLM. In this scheme, the adaptive sliding-mode observer was used at high speed and the saliency-tracking technology with the injection of high-frequency carrier signal was used at low speed. The principle of smooth switching of these two detecting technology was also proposed. Simulation and experiment studies show that the proposed combined self-sensing method was capable of precisely estimating the rotor space position in full speed range with stable suspension.Based on the rotor space-saliency effect and mutual inductance between the torque winding and suspension winding of PMBLM, a novel rotor position and displacement estimation scheme using the fluctuating high frequency voltage signal injection method was proposed to solve the detecting problem of the rotor space position and radial displacement. Analysis results show that this method can realize decoupling between horizontal and perpendicular directions of detected rotor radial displacement signals. The rotor radial displacement and rotor space position were also decoupled in this method.A digital control system for real-time control was designed based on TMS320F2812 digital signal processor(DSP). This system provides a reliable experimental platform for suspension operation and sensorless operation of the PMBLM and the permanent magnet biased radial-axial magnetic bearing.更多还原