Advanced Materials Research Vols. 139-141

Abstract: Combustion of power fuel in a large thermal power plant produces a great deal of harmful flue gas, which endangers personal safety of residents around it. In this paper, the injury mechanism of flue gas ejected by the thermal power plant is analyzed. The injury indexes of flue gas ejected by the thermal power plant are put forward. In order to improve the safety status of flue gas ejected by the thermal power plant, we developed a special instrument, which can detect on-line the injury indexes of flue gas ingredients, particle species, ejection speed and ejection flux in the ejected flue gas. The detection data can be used to assess the safety statue of the ejected flue gas, to predict the injury degree of the ejected flue gas to people and to provide basic data for establishing the valid emergency schemes.

Abstract: For the purpose of inspecting workpieces or equipments under severe environment, remote ultrasonic testing is of great significance to realize online inspection for processing products or vital equipments. The key problem to apply the remote ultrasonic testing is to keep the stability of the control system for the scanner. Therefore, how to eliminate the uncertain effect of time delay to keep the stability of the control system is the main difficulty in the online ultrasonic testing process. This paper proposed a slide mode approach to realize the position and attitude control for remote ultrasonic scanner. The implement of sliding mode controller with uncertain time delay, the solution of sliding surface and control function are studied. With the dynamic model of the scanner, the controller system is established according to the analysis of the control approach. The simulating results of the system proved the proposed sliding mode control method satisfies the requirements of stability for the remote control system.

Abstract: In stamping production the traditional manual feeding and pick-up manner can lead to potential safety problem. The automatic feeding and automatic pick-up device can ensure the production safety and ease workers’ labor intensity. A kind of automatic feeding and automatic pick-up device and its control system are designed. The configuration, function and working principle of the mechanism were described. Hydraulic system was taken as power supply. Siemens S7-200 was adapted as the center of control system, Hall-effect switch sensor CS1020 was used to detect the position of components. Control theory was studied and programmed. The device described in this paper can realize stamping automatic. Adjusting the position and number of sensors can realize the feeding and pick-up automation of all kind of workpiece, make the system has flexibility and suit the change of production.

Abstract: Medium and Small boilers, which are widely used, are common power equipments in power plants, Smelters, and chemical plants, and important to the safety and production of enterprises. In this paper, the main factors affecting the changing industrial boiler water level have been analyzed, and relevant control theory been studied. A cascade three-impulse supply water Fuzzy-PID control system and the implement of Fuzzy-PID control formula based on IPC and PLC have been introduced .The results of the simulation indicated that the design can overcome the illusive water level and can improve the performance of the system obviously. The cascade three-element feedback control system using IPC and PLC as the center control unit, combining the fuzzy control with the conventional PID control, obtains both virtues of the high precision of PID and the flexibility and adaptability of the fuzzy control.

Abstract: Automatic Tension Control (ATC) system is important for the cold tandem mill rolling of steel. Controller parameters must be adjusted continually according changing plant parameters to obtain better control performance. So it is very difficult to maintain strip tension within a tolerance with traditional PID controller. In this paper, the tension control systems are designed using variable parameters PID control on the basis of analyzing the dynamic tension control theory and the grey predictive control characteristic. Using the functional control can enhance the precision of the tension control. It is illustrated by simulation and Ansteel 1450mm mill production application results that the system dynamic response and robustness is advanced observably, and it has more favorable performance about restraining stochastic disturbances than conventional PID controller.

Abstract: Aiming at the shortcoming of the integral accumulation in the process of CVT ratio adjusting control, which is caused by the general PID control method, a new ratio adjusting control system based on the shift integral PID control method was designed. The theory of CVT ratio adjusting process and the enhanced control method were analized. The enhanced PID parameter tuning principle was presented. The test-bed of CVT ratio adjusting control was devised and adopted to do the CVT ratio tracing experiments. The experiments of step ratio from 0.45 to 1.45 and from 1.7 to 0.7 were made. The experimental results proved that the new ratio adjusting control system and the enhanced PID parameter tuning principle were valid, which made the real ratio trace the object ratio rapidly and steadily. The control performance of CVT ratio adjusting was improved.

Abstract: This paper explains and demonstrates how to design an anti-sway controller of overhead crane for eliminating pendulum of hook-headed. In this paper, we use Lagrange Equation in analytical mechanics to obtain a mathematical model of crane crab motion system. Then the paper comes up with a piece of new idea, i.e. applies linear quadratic regulator techniques to the anti-sway controller’ design of overhead crane. In order to make the designed linear optimal system meet the practical production requirements better, we use a parametric formula’s method of solutions to LQ inverse problems to obtain the weighting matrix Q. In fact, the method is simple and practical, and ensures the performance of closed-loop system is optimized. The paper will introduce the design steps of anti-sway controller of overhead crane and realization of anti-sway controller, which are new and original in this paper.

Abstract: GMAW welding remanufacturing is the process to form part layer by layer, that it is typical nonlinear transient heat conduction. During remanufacturing, parts undergo heating time after time that the thermal cycle fluctuates acutely and the distribution of temperature gradient is complex. And welding sequence is of significant for remanufacturing accuracy control. This paper has studied the effect of three typical welding sequences (sequential welding, spacing welding and end to end welding) on the deposition geometry control in GMAW remanufacturing, combining numerical with real-time identification. The comparison shows that the simulation results are in accordance with the actual data, which verified the valid of finite element model. From the analysis, it is found that the deformation of end to end welding is the least, and then is the sequential welding and the spacing welding is the largest.

Abstract: This paper analyzes the principle of hybrid turbocharging system in a vehicle diesel engine, and proposes motor control model about hybrid turbocharging system in steady engine operation condition according to energy imbalance of the exhaust gas. The high-speed motor can work as a motor or a generator in this control model of different engine condition. Then mapping algorithms about n-dimensional linear interpolation and BP neural network are presented to solve steady condition control problem of the hybrid turbocharging system. Each algorithm is applied to map same sample data, the simulation results reveal that BP neural network mapping algorithm is more suitable for the mapping control of hybrid turbocharging system because BP neural network has better generalization ability and faster processing speed.

Abstract: In the process of recycling chemical product in coking object, ammonia and tar were indispensable both metallurgy and agriculture, so the control of separation process for tar-ammonia was one of the most important control problems. Due to the density difference between the tar and ammonia was greater, easier to separate, the control method based on PID was used in field at present. But the control effect of traditional PID was not good because of environment change and fluctuation in material composition. Separation process for tar-ammonia was analyzed firstly, in view of the shortcoming of traditional PID control algorithm, single neuron PID control algorithm based on variable scale method was adopted through using optimization method. Detailed algorithm steps were designed and applied to tar-ammonia separation system. Simulation results show that by comparison with traditional PID algorithm, the algorithm have the following advantages: faster learning speed, shorter adjusted time and good convergence performance.