Advanced Materials Research Vols. 317-319

Abstract: The characteristics of electric pitch servo system are multivariable, nonlinear. In this paper, adaptive control method is used to satisfy the performance of rapid response, anti-interference and the location fast response non-overshoot. Neural networks model reference adaptive control is used in the speed loop to enhance the anti-interference performance and robustness. Fuzzy adaptive control is used in the position loop to satisfy the performance requirements of fast response and non-overshoot. The simulation results show that the adaptive control not only ensures strong anti-interference performance and robustness, but also achieve rapid response and non-overshoot exact location.

Abstract: An intelligent measure control system is designed to solve the problem of real-time intelligent detection of thermal defects of high voltage equipment at unmanned substations. This system uses a new method that continuous power of CC2530, a ZigBee wireless single chip, is provided by using monocrystalline silicon solar cells and thermoelectric generation modules. This method can also solve the problem that overheat faults can not be alarmed timely when efficiency of solar cells decrease during the continuous rainy days, and can realize real-time wireless detection and remote fault analysis of thermal defects of high voltage equipment. The supervisory programs of the remote PC and the upper computer are designed through VC + +.NET and the communication mode adopts C/S model based on TCP/IP protocols. The image files are saved as JPEG format by CImage class, which implements the real-time transmission of images. All the forgoing advantages provide a technical assurance to the remote and intelligent control of the heat vice of high-voltage equipment in the unmanned substations.

Abstract: With economic and practical as a starting point, we design and develop the hydraulic platform for proportional relief valve characteristics and automatic test and analysis system that based on virtual instrument and MATLAB software. A new modular design (MD) has been applied to test method for proportional relief valve characteristics, which realized the real-time data acquisition for multi-path pressure signal of automatic measurement & control and hydraulic system for steady state and dynamic state of DBE series proportional relief valve, and conducted analysis such as time domain, frequency domain, visualization and so on to collected data, obtained rather valuable test data and characteristics conclusion. Experiments show that this system has reasonable design and stable performance, enhances the test precision, improves the test method, enriches the analysis means and has good cost performance and research practicability.

Abstract: High pressure pump is one of the key components in Sea Water Reverse Osmosis (SWRO) desalination project. This paper introduced the development of an axial piston pump prototype which used as a high-pressure pump in SWRO desalination system. After the structure and technique data of the pump were illustrated, the main manufacturing processes of the prototype were introduced. The performance test of the prototype was carried out on an integrated water hydraulics test rig. After this, the prototype was used as a high-pressure pump on a SWRO experimental system. The test and application results prove that the pump is more efficient and quiet than other types, and is suitable for being used as high pressure pump in small and medium scale SWRO desalination project.

Abstract: To shorten the design period of a hydraulic system and achieve distributed cooperative design by experts, this paper proposes a model of the network collaborative design of a hydraulic system based on multi-agent technology. This model consists of three layers: the management agent layer, the middle agent layer and the resource agent layer. Its agent of the same layer adopts distributed structure, and each autonomous agent is constituted of a group of lower subordinate agents. This structure meets the need of distributed control of the cooperative design. By dynamic data exchange of agents, it carries out their communication, coordination and conflict resolution, and finally gets the global target. From the developed example, a multi-agent system can easily integrate existing engineering design tools with analysis tools. Its concurrent design process can improve design efficiency.

Abstract: The operating mode of large flow quantity and small temperature difference is used in the traditional serial heating system, which results in a serious problem of hydraulic misadjustment, leading to visible temperature difference among different rooms. In this paper, in order to realize the hydraulic dynamic equilibrium of heating system and control of household heating, the automatic flow control valves are used for the control of flow rate. On the basis of theory analysis of hydraulic misadjustment, the results show that: the efficiency of heating system and control of household heating can be improved significantly, as well as the energy saving up to 20%.

Abstract: Silk-Screen Print Technique was used to print roughness elements at the leading edge of a swept wing for crossflow (CF) dominated Laminar Flow control (LFC) in fluid dynamics. Crossflow was studied to be sensitive to the spacing and height of the roughness elements, as well as the density of the metal ink. Experiments in our research showed silk-screen print technique can precisely print the elements to dominate to delay transition.

Abstract: Abstract：The working mechanism of the stationary crescent for radial compensation in the inner mesh gear pumps was studied in this paper. The force of the top and bottom stationary crescent in one hydraulic pressure changing cycle was analysed. The pressure distribution on the top and bottom stationary cressent in different positions and the hydraulic force at the x，y direction were determined.Under the condition of the force of the top and bottom stationary crescent is least and the two stationary crescents stay close to the tooth crest of internal gear and external gear to form radial seal，the angle of the end of the top stationary crescent in the high pressure area and the fixing angle of the seal stick was optimized. Experiment results show that the volumetric efficiency is 0.94 when the outlet pressure reach to 30Mpa, and the oil temperature is less than 55°C, there is no abrasion on the two sationary crescents and the tooth crest.

Abstract: Hydraulic thrust system is a critical part of shield tunneling machine. Automatic trajectory tracking control is a significant task of thrust system during tunnel excavation. In this article, plane mechanical structure diagram of the thrust system and path planning method are illustrated at first. An integrated control system is proposed to achieve the automatic control of the thrust trajectory. The control system consists of one trajectory planning controller for both cylinders and an individual cylinder controller for each of hydraulic cylinders. Trajectory planning controller is used to generate respective displacement signals of double-cylinder in every thrust stroke and each of cylinder controllers is used to realize the precise control of the given thrust trajectory. Variable-gain PID control strategy applied to achieve the precise tracking control of thrust trajectory under several typical working conditions are done at last. The experimental results demonstrate that variable-gain PID control have good performances with short response time and small overshoot regardless of changes of working conditions.

Abstract: Establish interior flow field model of the control valves under the blocking fault, using the CFD simulation and analysis the internal flow field of the control valve under the blocking and the trouble-free. The research indicates that blocking changes the fluid state of motion, causes the vortex in the valve core, resulting energy loss and reduces valve control performance.