【作者】 姚福来；

【导师】 孙鹤旭；

【作者基本信息】 河北工业大学 ， 控制理论与控制工程， 2012， 博士

【摘要】 在国民经济的众多领域，存在大量的机电设备，只要需要用多台设备来共同完成一件任务，就存在一个系统的整体能耗最低问题，也就是系统的整体效率优化问题。随着节能形式的日益严峻和环保工作的日益发展，这一问题变得越来越重要。当前，人们对各种系统的优化研究已经广泛开展，但是，1）较普遍意义上的机电设备的优化理论还没有统一的结论；2）很多系统的模型难于建立，所以目标函数的优化过程很难进行；3）很多被广泛采用的经典控制方法，如用于恒值控制的PID调节方法，由于方法本身就没有考虑能耗最小化问题，所以也就不可能自然而然地实现满足工艺条件下的最低能耗运行，但是人们在很多领域又没有发现最优的控制方法，所以也就不可避免的存在能量浪费，即使是象南水北调这样的世界级工程，其机电设备的节能优化问题依然没有解决。本文的目的是寻找机电设备的优化控制方法和优化切换方法，主要内容如下：1）分析各种机电设备的能量表达式，例如势能、动能、电能、热能、磁能等，所用的机电设备不同，系统的总功耗表达方式也不同，本文给出机电设备组成系统的能耗标准化形式及整体效率函数；2）由于很多系统的动态模型和静态模型都难以准确地建立，所以不论是静态优化还是动态优化工作就难以准确进行，难以给出准确的优化问题的解；本文依靠机电设备效率函数的形状,而不依赖于系统的准确模型，固定总负荷量，并假设每台参与工作的设备负荷率大于零，给出并证明了机电设备组成系统的最优调节方法和最优运行台数，变化总负荷量，给出最优切换方法及最优切换点，从而将机电设备的动态优化和静态优化合而为一；3）针对调速水泵和调速风机，给出了一种优化控制方法和一种优化切换方法，并给出最小电耗值，对于由相同水泵或风机并联组成的系统，其最优控制方法是保持各台运行设备的负荷率相等；4）针对定速水泵和定速风机，给出了一种优化控制方法和一种优化切换方法，给出最小电耗值，对于由相同水泵或风机并联组成的系统，其最优控制方法是保持各台运行设备的负荷率相等；5）针对由多台相同电动机驱动的高速列车和输送机械等系统，对于固定的总转矩，得出最优的控制方法，其最优控制方法是保持各台运行设备的负荷率相等，对于变化的总转矩，得出最优的切换方法。6）针对水泵风机系统存在的控制稳定性问题，利用水泵风机的相似定理，推导出稳定控制的判别方法和稳定控制方法。本文最重要的结论是提出了机电设备组成系统的优化调节方法和优化切换方法，其证明方法是基于：1）效率函数可以近似地看作是过原点的非负的凹函数；2）固定总负荷量，假设每台参与工作的机电设备负荷率大于零，推导出各台运行设备的最优负荷分配控制方法;3）改变总负荷量，以单位负荷的能耗为目标函数，推导出最优切换方法和最优切换点,总负荷增加时，确定出n和n+1台运行设备的最佳切换点，总负荷减小时，确定出n和n－1台运行设备的最佳切换点。更多还原

【Abstract】 In various fields of national economy, there are a lot of mechanical and electrical equipment,there exists a minimum energy consumption method to complete the same task, that is theoptimizaition of the overall efficiency of the system.With the development of the energy-saving and environmental protection, this issue becomesincreasingly important.At present, the research about optimization of various machine are widely carried out.However, the optimization theory of the mechanical and electrical equipment in the commonsense there is no uniform conclusion. Another problem is that many typical control methods arenot the best, like PID. Although this method has been used around the world, but it is notoptimal.This control way doesn’t consider the total power factor, so it can not realize theminimum power consumption. We can say that, at present, there still haven’t optimal controlmethods which can accurately control energy-saving effect in many fields. Even in the South toNorth Water Transfer Project of China, which is the largest water project in the world, is noexception.The same problems exist in many areas.The purpose of this paper is to find out the optimal control method and optimal switchmethod for mechanical and electrical equipment.The main content of this paper is as follows:1) Analysis of the forms of energy, potential energy, kinetic energy, electricity, heat andmagnetic energy and so on, the expression of the system’s total power consumption is indifferent ways for different mechanical and electrical equipment. This paper presents a standardenergy consumption function and an overall efficiency for mechanical and electricalequipments;2）Since it is difficult for the dynamic model and static model of many systems to beaccurately established, it is difficult to give accurate solution of optimization; only dependingon the shape of the efficiency function of electrical and mechanical equipment, the staticoptimization method is given and proved, it does not depend on the exact model of the system,and the optimical switching method is given also, it combines the dynamic optimization andstatic optimization into one method;3) This paper presents a kind of optimal control method and a kind of optimal switchingmethod for variable-speed pumping (or fan) stations with similar parallel pumps (or fan), andgives the minimum total power consumption. The optimal control method is to keep the same load for each pump or fan.4) A kind of optimal control method and a kind of optimal switching method for constant-speed pumping (or fan) stations with similar parallel pumps (or fan) is given, and gives theminimum total power consumption. The optimal control method is to keep the same load foreach pump or fan.5) This paper presents a kind of optimal control method and a kind of optimal switch methodfor a high speed train or a conveyor witch is driven by several motors, and gives the minimumpower consumption. The optimal control method is given for the fixed total torque, the optimalcontrol method is to keep the same torque for each motor, and the optimal switch method isgiven for the changing total torque.6) After the application of frequency converter, the speed of pump or fan can be adjusted, theinherent characteristics of some centrifugal pumps or fans imply instability. Based on thesimilitude law of centrifugal pumps, the stability criterion and control method of centrifugalpumps and fans is given.The most important conclusion of this paper is to propose the optimal control method and theoptimal switching method, the proof is based on:1) The efficiency function can be considered approximately a concave non-negative functionthrough the origin;2) Each load of all running equipments is greater than zero, and the total load is constant, thestatic optimal control method is given.3) Consider a load capacity per unit power of common system as an objective function, andthe total load is variable, the dynamic optimal switching method is given.The total laodincreases, we decide the switch point of optimal from n to n+1, when the total load c decreases,we decide the switch point of optimal from n to n-1.更多还原