Three Theoretical Problems in the Control of Rotating Machines

旋转机械控制中的三个理论问题

• 批准号: EP/E046290/1
• 负责人: Seamus Garvey
• 金额: $ 28.96万
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FE046290%2F1
• 关键词: Three; Theoretical; Problems; Control; Rotating

This project addresses theoretical aspects of the control of vibrations in rotating machines but its ultimate motivations are entirely practical. Two of its three main strands deal with active control methods for machines. There is a widespread concensus that further significant progress in efficiency, power-density and cost-reduction of rotating machines is available through active control. These two strands are different but complementary and each has clear value. The third main strand of this project relates to the analysis of machines in which an electrical motor/generator forms an integrated part. The three strands are connected by a single underlying mathematical framework.In any given operating condition, the dynamics of a rotating machine can be represented as a linear second-order system - at least for small oscillations. The characteristics of the system are determined by three square matrices (multiplying the zeroth, first and second derivatives of displacement). For a static structure, these are named the stiffness , damping and mass matrices respectively. Static structures can be relied-upon to have certain properties which make their analysis and control less difficult than the control of machines. The important differences include: (a) the damping matrix for a rotating machine can have very large skew-symmetric components due to gyroscopic/Coriolis effects caused by the rotation; and, (b) in the analysis of coupled electromagnetic and mechanical dynamics, the mass and damping matrices contain components which vary periodically with time. Methods for analysing second-order systems which have emerged within the last 10 years are to be applied to rotating machine systems.The first part of the project deals with so-called modal control, an appropriate representation of the equations of motion followed by a model reduction in order to simplify significantly the application of active control to rotating machines. This presents an extension of conventional modal control to systems with large gyroscopic/Coriolis effects. The benefit to machines engineers is that they can implement distinct controllers for different aspects of the machine behaviour and these controllers will not interfere with each other at all.The second part of the project helps engineers to do the design of the physical system at the same time that they are doing the design of the controller. For magnetic bearings in particular, three distinct considerations apply in the design of the amplifiers: maximum voltage, current and power. Existing formal controller-design methods cater only for limiting the magnitudes of current but it is obvious that a balanced account should be taken of all three and one representation of the dynamics of second-order systems appears to indicate how this can probably be done.The third part of the project applies to machines where an electrical motor/generator is integrated into the machine. Examples of such machines include vacuum-pumps, compressors, axial-flow fans, ship-propulsion pods, downhole pumps, automotive fuel-pumps, hydraulic pumps for power-steering, etc. The magnetic field causes an interaction between the mechanical and electrical dynamics which can make the machine unstable in certain operating conditions. One established analysis route produces a linear system which varies periodically with time. Because of particular features of the systems produced, standard methods for analysing these periodic systems (to determine their stability) fail badly. New methods will be produced.The project is based at the University of Nottingham but its success depends upon the participation of two distinguished collaborators from other universities: Prof. Ion Zaballa at Universidad del Pais Vasco in Spain and Prof. Peter Lancaster at University of Calgary, Canada.

该项目涉及旋转机械振动控制的理论方面，但其最终动机完全是实际的。它的三个主要部分中的两个处理机器的主动控制方法。人们普遍认为，通过主动控制，可以在旋转机械的效率、功率密度和成本降低方面取得进一步的重大进展。这两股是不同的，但互补的，每一个都有明确的价值。这个项目的第三个主要部分与电机/发电机构成一个整体部分的机器分析有关。这三条线由一个单一的底层数学框架连接起来。在任何给定的运行条件下，旋转机械的动力学可以表示为线性二阶系统——至少对于小的振荡是这样。系统的特性由三个方阵确定（乘以位移的零阶导数、一阶导数和二阶导数）。对于静力结构，它们分别称为刚度矩阵、阻尼矩阵和质量矩阵。静态结构具有某些特性，使它们的分析和控制比机器的控制更容易。重要的区别包括：(a)由于旋转引起的陀螺仪/科里奥利效应，旋转机器的阻尼矩阵可能具有非常大的偏对称分量；(b)在电磁和机械耦合动力学分析中，质量和阻尼矩阵包含随时间周期性变化的分量。近十年来出现的二阶系统分析方法将应用于旋转机械系统。该项目的第一部分涉及所谓的模态控制，即运动方程的适当表示，然后进行模型简化，以便显着简化主动控制在旋转机器上的应用。这将传统模态控制扩展到具有大陀螺仪/科里奥利效应的系统。对机器工程师的好处是，他们可以为机器行为的不同方面实现不同的控制器，这些控制器根本不会相互干扰。项目的第二部分帮助工程师在进行控制器设计的同时进行物理系统的设计。特别是磁轴承，在放大器的设计中有三个不同的考虑因素：最大电压，电流和功率。现有的正式控制器设计方法只满足限制电流的大小，但很明显，应该考虑到所有这三种情况，而二阶系统动力学的一种表示似乎表明了如何可能做到这一点。该项目的第三部分适用于电机/发电机集成到机器中的机器。这类机器包括真空泵、压缩机、轴流风扇、船舶推进舱、井下泵、汽车燃油泵、动力转向液压泵等。磁场引起机械和电动力学之间的相互作用，这可能使机器在某些操作条件下不稳定。一个已建立的分析路线产生一个随时间周期性变化的线性系统。由于所产生的系统的特殊特征，分析这些周期系统（以确定其稳定性）的标准方法严重失败。将产生新的方法。该项目以诺丁汉大学为基地，但它的成功取决于来自其他大学的两位杰出合作者的参与：西班牙国立瓦斯科大学的Ion Zaballa教授和加拿大卡尔加里大学的Peter Lancaster教授。

项目成果

Eigenvalue and eigenvector derivatives of second-order systems using structure-preserving equivalences

使用结构保持等价的二阶系统的特征值和特征向量导数

• DOI: 10.1016/j.jsv.2009.01.032
• 发表时间: 2009
• 期刊: Journal of Sound and Vibration
• 影响因子: 4.7
• 作者: Abuazoum L

Dynamic effects in rotors of large horizontal-axis wind-turbines with free-moving masses in blades

叶片中具有自由移动质量的大型水平轴风力涡轮机转子的动态效应

• 发表时间: 2008
• 期刊: Institution of Mechanical Engineers - 9th International Conference on Vibrations in Rotating Machinery
• 作者: Garvey S.D.

Vibration absorption for quasi-periodic excitation - Methods and two renewable-energy applications

准周期激励的振动吸收 - 方法和两种可再生能源应用

• 发表时间: 2008
• 期刊: 23rd International Conference on Noise and Vibration Engineering 2008, ISMA 2008
• 作者: Garvey S.D.

Coupling between rotor planes due to deformations of components having a helical direction

由于具有螺旋方向的部件变形而导致转子平面之间的耦合

• 发表时间: 2008
• 期刊: Institution of Mechanical Engineers - 9th International Conference on Vibrations in Rotating Machinery
• 作者: Garvey S.D.

Enriching balancing information using the unbalance covariance matrix

• DOI: 10.1243/09544062jmes1181
• 发表时间: 2009-08
• 期刊: Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science
• 作者: S. Jiffri;S. Garvey;A. Rix