Research On Speed Regulation Driving And Device Of Rotary Machinery Based On Power Splitting

In the production process of China's basic industries, fans, water pumps and other rotating machinery are the power equipments which have wide range of applications, have the largest number, and take the largest share of energy consumption. However, for the lack of efficient and reliable transmission technology, the applications of major technology method of large equipments'energy-saving operation--the variable-speed control is severely restricted. Thus, the traditional fixed-speed, throttle adjustment method is still widely used in large fans and water pumps system, resulting in great waste of energy.In this context, this paper presents a new research thought that is substituting for the traditional full power speed-control by part power speed-control, using the existing mature, reliable, small and medium-power speed-control technology to achieve the purpose of high-power rotating machinery's speed control. It aims to meet the demand of large-scale rotating machinery's energy-saving operation, and refers to the power split transmission technology concepts put forward by foreign countries in recent years.This paper starts with the analysis of the power split speed-control transmission mechanism and possible technical solutions, carries out the research of a typical transmission system apply theory and technology; by the development of a mixed speed-control transmission device, with high efficient mechanical transmission and hydraulic speed control, it carries out the related design theory and method, key technology, prototype development and experimental research. The research based on power split speed-control transmission technology and equipment, leads to the research of new methods of large fans and water pumps system's flow control, and explores a new method of energy-efficient technologies.Major research work and achievements of this paper include the following three aspects:1. Study a new technology which applies to large-scale rotating machinery's speed control transmission. It researches and analyzes the technology solutions and drive mechanism of power split transmission system, establishes an effective system transmission model, masters the analysis method of power split and its relationship with the transmission process. It researches key issues such as the speed characteristics, power split, coupling mechanisms, power distribution mechanism and transmission efficiency, forming a reletively complete system overall transmission design theory and method.2. Develope a hydro-mechanical variable-speed drive (HMVD) device. According to the functional requirements of the overall design, this paper researches some issues, such as the transmission mechanism's assembly programs of speed control components and multi-degree of freedom differential gear, the design basis and design methods of the mechanism and structural design. It explors the issue of reverse speed control and develops a new type of speed control unit components for the first time, carries out a research about cutting off and locking the power flow in the design of multi-degree of freedom differential gear, and successfully developes a prototype with independent intellectual property rights and carries out a pilot study.3. Research and present a new complex flow control method of pumps and fans system based on HMVD.This paper researches and presents the coordination adjustment principle of speed control and throttle adjustment for the flow control and energy saving of large fans and water pumps system, based on the characteristics of HMVD transmission device that its power flow can be splitted. It researches the speed and throttle adjustment method, with the combination of system pipeline flow characteristics and part power hydraulic speed-power characteristics. It sets the lowest energy consumption as the goal, establishes a coordination optimization model with speed and throttle, and can determine the best speed and throttle points according to system operating conditions. This method breaks through the traditional energy-saving theory of replacing the throttle adjustment entirely with speed control, can reduce the inevitable power loss of existing full power hydraulic speed control system, and explores a new technology direction for pumps and fans energy saving research.