极端环境永磁电机及其驱动控制系统的关键基础问题

The extreme environment motor and its drive and control system should work in extreme low and high temperature，vacuum and extreme high pressure conditions. This kind of motor system plays basic and key part in extreme exploration and development such as in deep space，deep sea and deep earth. The extreme environment brings some new phenomena and problems in the motor system. The physics phenomenon and process are quite different from those in normal environment. The coupling of the electromagnetic field，the fluid field，the loss，the thermal field，and the stress becomes more prominent. The features of the materials of the motor and the elements of the drive and control circuit changes evidently. The nonlinearity of the parameters of the motor and system increases greatly. The performance of the motor system is quite different from the normal motor systems. The drive and control strategy becomes very complex. Considering the particularity of the extreme environment motor system，the fundamental theory and key technology for the motor design，drive and control will be investigated. The research will include: the analysis and computation for the electromagnetic，thermal，fluid and stress field，the variation process and regularities of the performance of materials and elements for the motor system，the balance of loss and thermal design，the design method and optimization，the drive and control strategy. The motor system that could work in the temperature range from -100°C to 180°C，and in the pressure range from vacuum to 140MPa will be developed，of which the power density will be higher than that of the existing motor systems in other countries. The mechanism and regularities for performance variation of the extreme motor system will be revealed entirely. The theory and technology of the motor system will be developed. The environment adaptation ability of the motor system will be promoted greatly.

极端环境电机系统指可以在环境温度和压强大范围变化条件下工作的电机驱动与控制系统，是深空、深海、深地等极端探测与开发领域的关键与基础部件。极端环境给电机系统带来新的问题，内部物理现象和过程发生变化，电磁场、流体场、损耗、温度场、应力场之间的耦合问题突出，材料及器件特性发生变化，参数非线性变化，电机系统特性发生变化，驱动与控制策略复杂。课题将针对极端环境下永磁电机的基本理论问题及关键技术进行系统的研究，主要内容包括：极端环境电机的电、磁、热、流体、应力场的分析与计算；极端环境下机电材料与器件特性演化规律及模型；发热散热机理及热平衡方法；极端环境条件下永磁电机设计准则和优化设计；极端环境电机驱动控制技术。研制出能在-100℃～180℃温度范围、真空～140MPa压强范围工作的永磁电机系统。课题将揭示极端环境下电机系统特性的变化机理和规律，形成系统的理论与技术体系，极大地提高电机系统的环境适应性。

极端环境电机是复杂的电磁系统，涉及多学科，且由于工作环境的特殊性，很多常规设计手段和所用材料的特性均发生了很大的改变，这都给极端环境电机的研发带来了极大的考验。为了设计出适合运行在极端环境的电机系统，本研究首先对高低温、真空至高压强环境下材料特性测量方法和典型性能参数变化规律与影响机理以及材料特性的非线性和耦合特性的精确描述方法进行了深入的研究。确定了高温高压等极端环境中材料的变化特性，并据此研究了高压环境中永磁电机内的电磁损耗。并对高压环境充油电机内流体损耗的机理及计算方法做了详细的研究，特别是针对真空环境和高压环境下电机温度场的分布情况，做了深入的分析。同时研究了极端高压环境永磁电机各物理场之间的耦合关系。并建立了适合高压极端环境运行电机的设计准则并成功研制了样机。.对极端环境下永磁电机驱动器的设计进行分析研究。详细研究了电机系统参数、状态与运行条件之间的匹配关系，电机系统性能综合优化的控制策略，以及电机系统的安全运行机制。.所设计的针对极端环境的无刷直流电机可能存在续流角过大的问题。这会导致电机的长时间换相续流，从而出现转矩波动、机械振动和噪声等问题。因此，深入研究了各种因素对无刷直流电机换流的影响，为电机设计提供依据。.为了电机在极端环境下的安全运行，需要研究单电流传感器方法。针对现有方法控制算法复杂、电流畸变严重、低转速运行性能差等问题，提出了一种新型的相电流重构技术——零电压矢量采样法。同时，提出一种基于零电压矢量采样法的功率管开路故障诊断方法。.针对极端环境，提出了两种优化的控制策略。对于无刷直流电机控制系统，对换相续流可控的驱动电路拓扑进行了研究。首先从理论上证明了逆变器直流母线电压分段控制对换相续流角的实时调节作用；然后构造了双极性C-dump变换器。对于永磁同步电机控制系统，对不同拓扑结构的容错控制策略进行分析，提出一种基于零电压矢量法的三相四开关容错控制策略。