Applied Mechanics and Materials Vols. 268-270

Abstract: The article gives analysis of long-term and perspective tasks of automating EAF, particularly relevant to the conditions of domestic production. The results of studies on quality control of foaming slag in the super-power EAF-135 OJSC "Seversky Pipe Plant" are shown. We made the conclusions about the possibilities of using the electrical mode parameters for the operational control of the processes of smelting steel and ferroalloys.

Abstract: Through measuring and analyzing the location error of two-dimensional precision positioning system based on the motion control card, and according to the deficiency of the first error compensation, a strategy that enhance addition based on first error compensation was put forward. That using closed loop control to compensate and correct the location error makes the positioning accuracy improved obviously, and achieves an ideal compensation effect. Under the loading conditions, X axial positioning accuracy reached 11μm, Y axial positioning accuracy reached 10μm.

Abstract: The system of high-low voltage drive experiment of asynchronous motor based on PLC software circular- allotting is introduced in this paper. Its control circuit is novel and concise, combination is convenient.

Abstract: This paper reviews the development of static synchronous compensator (STATCOM), and analylizes the structure of its main circuit, its working principles and control strategies. At last, this paper comes to a conclusion of technical characteristics of STATCOM and outlook of its development trends. Fast acting STATCOM, a representative of FACTS family, is a promising technology which is extensively used as state-of-the-art dynamic shunt compensator for reactive power control in transmission and distribution system. STATCOM controller employs various solid-state converter topologies, magnetics configurations, control algorithms, and switching techniques and so on. The development of STATCOM controller has been well reported in literature with its versatile application in power system. Thus deep investigation of STATCOM from the perspective of its intelligent control and the configuration of STATCOM’s main circuit is valuable.

Abstract: To improve the printed circuit board (PCB) manufacturing process, it is important to have an automatic inspection system that classifies information regarding defects in solder joints. This paper proposes a quality decision system for solder joint defect classification on a PCB. An experiment was conducted to demonstrate the application of the system. The results showed that the inspection accuracy reached 94%, which is superior to the results achieved by other methods. The results of this study provide an effective solution for the inspection of the solder joint quality.

Abstract: Based on the present problems existed in electric load characteristic statistical indexes, a correlation analysis method for load characteristic statistical indexes is proposed in this paper. Low-level correlation indexes are extracted by using correlation analysis, then the linkage analysis theory in econometrics is applied and the load characteristic indexes are analyzed by using vector auto-regression model. The Synchronous movement trend and causal leading relationship among electric load characteristic indexes are confirmed by co-integration test and granger-casualty analysis. The purpose of this paper is to help power decision makers grasp the alteration situation of load characteristic indexes comprehensively and analyze correlation indexes accurately, so it can enhance the monitoring, forecasting and early-warning function of electric system.

Abstract: This paper is to design a kind of temperature control system that could satisfy the requirement of baking equipment used for farm product. The system installed an AT89S51 single chip microcomputer as controller. The structure of the system was loop-locked and the temperature was detected by a team of DS18B20 digital sensors. The simulation of the temperature control system was implemented by the Simulink. The result indicates that the system can realize the function of controlling the temperature variation of the baking house.

Abstract: The straightness error was measured from a certain part surface by CMM. The paper expounded the principle of error separation technique, and separated the straightness error into deterministic error and random error. It proved strictly an opinion that random error is obedient to normal distribution. Extraction point of random error far outweighs the extraction point which is obtained from deterministic error. Based on the principle of sampling signal, a conclusion can be pointed out that utilizing the characteristic of random error to recover the signal of straightness error without distortion is feasible and normal distribution model can be used in the computer simulation to study the problem of extraction point.

Abstract: The forward kinematics analysis of parallel manipulator is a difficult issue, which has been studied by many researchers recently. In this paper, in order to solve the difficult issue, a new computing method with higher calculation accuracy, good operation steadiness and faster speed is mentioned. Firstly, the mathematical model of direct kinematics of the Stewart platform is founded, which is nonlinear equations. Secondly, with the rapid development of artificial intelligence technology, Memetic algorithms (MA) are applied to solve the systems of nonlinear equations more and more, replacing the traditional algorithms. MA is a kind of meta-heuristic algorithm combined genetic algorithms (GA) with local search at the end of iteration. Finally, the validity of this algorithm has been testified by simulating iteration operation. The numerical simulation shows that MA can surely and rapidly get global optimum solution and greatly improve convergence rate. Thereby, MA can be widely used as a general-purpose algorithm for solving the forward kinematics of parallel mechanism.

Abstract: Abstract:This paper studies the control strategy of doubly-fed wind turbine to capture the maximum wind energy.The maximum wind energy capture is a more important part of the wind generation. Due to random fluctuations of the wind speed, to track the maximum power of wind turbine,we need to constantly adjust the speed of the generator, so that the generation run in the optimal tip speed ratio in different wind conditions,in order to achieve maximum power tracking. In this paper, the stator output indirect control the generator speed to achieve maximum wind energy capture,and decoupling control of active power and reactive power can be achieved.the MATLAB / SIMULINK simulation results verify the correctness and feasibility of this method.