Advanced Materials Research Vols. 383-390

Abstract: As a typical power electronic circuit, the dynamic model of boost converter can be viewed as a mixing or interacting system between the discrete event and continuous time variable, also known as hybrid dynamic systems. By using of hybrid dynamic systems theory, a hybrid model of boost converter was established and simulation was carried out to verify the validity of the method in the MATLAB. Compared with traditional state-space averaging method, a more accurate model of boost converter was obtained without treatment of approximate linearization based on hybrid dynamic theory.

Abstract: Faults occurrence is inevitable in real world and a practical alternative approach is the reduction of fault consequences. Despite of this, the majority of buildings control systems do not have such mechanisms. Thus, this work proposes a procedure for the modeling of control systems for intelligent buildings which considers their functional specifications in normal operation, and in case of faults occurrence. The procedure adopts the concepts of discrete event system, holon, and Petri net and its extensions. It is presented some models derived from case studies, and mechanisms to fault-diagnosis, decision and reconfiguration.

Abstract: This paper analyzes the background modeling mechanism using Gaussian mixture model and the stability /plasticity dilemma in parameters estimation of GMM background model. To solve the slow convergence problem of Gaussian mean and covariance update formula given by Stauffer, a new updating strategy is proposed, which weighs the model adaptability and motion segmentation accuracy. Experiments show that the proposed algorithm improves the accuracy of modal learning and speed of covariance convergence.

Abstract: Phenomenon of electrostatic hazards is becoming increasingly prominent with wide application of microelectronic elements. Electrostatic Discharge (ESD) is an extremely complex process, which is not only related to the materials, the object shape and the value of discharging circuit resistance, but also always involved in very complicated process of gas breakdown, so ESD is also a stochastic process which is difficult to repeat. According to the request of standard IEC61000-4-2, simulation circuit of the equivalent Human-Metal Model is established, discharging process is simulated and analyzed, and the influence laws of circuit parameters and distribution parameters for ESD current waveform are obtained. Thus the structure of discharging circuit and element parameters can be determined, test results can be verified to some extent, and the characteristics and influencing factors of ESD process can be known better. Simulation results show that waveform parameters are all within the range of standard errors, which proves that the design of model parameters is correct, the analysis of ESD process is reasonable.

Abstract: A method was proposed based on principle of EKF (extended Kalman Filter) state estimation to improve the localization precision of differential drive mobile robot. The robot position was estimated by Multisensor fusion of Odometer and laser, which kinematics model, the robot sensor perception model and the sensor error model were presented. The models were introduced into the state estimation and covariance matrix update equation of EKF with match convergence condition and nonlinear error correction covariance matrix.The specific iteration equation was acquired.The simulation results demonstrate the approach of modeling and fusion is accurate and validity.

Abstract: Power flow analysis plays a significant role in both design and operational stage. The purpose of any load flow analysis is to compute accurate steady state voltages and voltage angles of all buses in a network, the real and reactive power flows into every line and transformer, under the assumption of known generation and load. This paper focus on fast decoupled flow, a practical power system has been used as an example to introduce its application in actual calculation, what’s more, develops a fast decoupled load flow calculation program for n-node system by taking advantage of MATLAB. A visual GUI interface is also established with MATLAB. In addition, the paper proposes a new simple power system data format, different from the IEEE standard one. The correctness and simplicity of the proposed format is verified through IEEE-5bus,-9bus,-11bus,-39bus systems.

Abstract: The purpose of this study is to produce a modeling capability for integrated flight dynamics of flexible aircraft that can better predict some of the complex behaviors in flight due to multi-physics coupling. Based on the studying of the exiting modeling approaches, the author put forward a new modeling method, and developed a new formulation integrating nonlinear rigid-body flight mechanics and linear aeroelastic dynamics for fully elastic aircrafts using Lagrangian mechanics. The new equations of motion overcome the disadvantages of the exiting methods, and include automatically all six rigid-body degrees of freedom and elastic information, the seamless integration is achieved by using the same reference frame and the same variables to describe the aircraft motions and the forces acting on it, including the aerodynamic forces. The formulation is modular in nature, in the sense that the structural model, the aerodynamic theory, and the controls method can be replaced by any other ones to better suit different types of aircraft.

Abstract: Vector control technology is regarded as a kind of controlling manner of AC asynchronous motor and it has already become the first method of the high-performance variable-frequency speed regulating system. According to the basic principles of induction motor vector control, this paper constructs simulation model of rotor magnetic field oriented vector control system based on the MATLAB software. The paper analyzes the operation of motor on the basis of mutation of a given speed and sudden load. The simulation result including the oscillogram speed, torque,three phase current and two phase current were presented and analyzed. Results show that it has good dynamic performance, and it realizes the decoupling control system.

Abstract: According to the China Aviation Industry Standard HB6129 “The requirements of aircraft lightning protection and test method” and standards of foreign countries. The high voltage generator was used to make the lightning attachment point test on a scale model of airplane. The lightning attachment zone was determined, and the result was agreed with the actual lightning experience of F-4 aircraft. The technical factors such as test method, the model scale, gap spacing, and polar discharge relative positions in respect to the model are related to the laboratory test; the lightning discharging theory will be discussed in detail. The test method has been proved feasible and the experience of test research work has accumulated for future use.

Abstract: For simplicity and not losing generality, a half-vehicle model with 4 rigid DOFs is presented by mobility or impedance method and transfer matrix technology, which bring the flexibility of the body to the proposed model easily and conveniently, instead of complex differential and state space equations. Based on the multi-objective optimization, a synthetic cost function is proposed to investigate the dynamic characteristics and achieve the optimal control of suspensions. The numerical examples are performed to show the validity and efficiency of the presented model, and some valuable conclusions are also obtained to guide the optimal design of suspensions.