Advanced Materials Research Vols. 433-440

Abstract: The development of an new method for formulation of transduction or input and output representation for a giant magnetostrictive actuator (GMA) is presented. The transduction model is built through the application of a bond graph modeling approach which includes the mechanical dynamics and the electro-magneto-mechanical interaction of the actuator. Simulation and experiment behavior correlation are also presented. The bond graph model allows for in-depth investigation of dynamic behavior of GMA, such as energy conversion, output displacement or force and so on.

Abstract: Motor is one of the cores of electric vehicle, the performances of motor directly impact the performances of electric vehicle. The development of drive motor applied in electric vehicle is reviewed, the advantages and defects of several kinds of the motor developed in recent years are summarized, and the applications of control strategy too. The development of permanent magne brushless motors is prospected.

Abstract: In order to investigate the effect of high power square-wave pulsed electric field (HPEF) on parasite eggs, Ascaris suum eggs are selected as an example. By changing the voltage, frequency, acting time of the pulse, electrode shape, and living environment of Ascaris suum eggs, this paper discusses the relationship between parameters of HPEF and the effect of destroying Ascaris suum eggs. Then the direct smear for microscopic examination is adopted for counting the death rate of Ascaris suum eggs. The research result shows that with fixed experiment conditions the death rate of Ascaris suum eggs increases with the increase of electric field voltage and acting frequency. Furthermore, the acting time has weak effect to the death rate, and the death rate with pin-pin electrode is the highest. When pulsed voltage is fixed and higher than 60kV with pin-pin electrode, the death rate is always higher than 80%. However, the death rate in pin-board electrode is inconsistent. The experiment results indicate that HPEF has effective impact on Ascaris suum eggs while feasible processing parameters are selected, so it can be used in destroying Ascaris suum eggs and some other parasite eggs.

Abstract: A third-order circuit system with nonlinear negative capacitance is studied. The dynamical equation and state equation of the system are established. By the phase portraits, the motions of the system are studied under the definite parameters. And by bifurcation diagram, the route from periodic motion to chaos is studied under the presented system parameters. Two anticontrol methods is used to control the periodic motion of the system to chaos. The phase plane portraits and bifurcation diagram of the anticontrolled system are obtained. The threshold values of the anticontrol values of the two control method are obtained. The advantages of the two anticontrolled methods are that the collect of the control signals are simple and can put on any time and the periodic system can be asymptotically chaotic with small control. The orbits of the system can be anticontrolled by these two methods according to our target

Abstract: The complex dynamics characters of a third-order circuit system with nonlinear negative capacitance are studied. The dynamical equation and the state equation of the system are established. By the phase portraits, the motions of the system are studied under the definite parameters. And by bifurcation diagram, the route from periodic motion to chaos is studied under the presented system parameters. Two feedback methods are used to control the chaos of the circuit system. One is an adaptive method and the other is the feedback of states and parameter adjustment method. The phase plane portraits and bifurcation diagram of the controlled system are obtained. The advantages of the two controlled methods are that the collect of the control signals are simple and can put on any time and the chaotic system can be asymptotically stabilized to equilibriums with small control. The orbits of the system can be controlled by these two methods according to our target.

Abstract: Open systems consist of autonomous and heterogeneous agents who interact in order to exchange or negotiate information, knowledge, and services. The principal challenge in agent communication research is to enable flexible and efficient communication among agents. Jade follows FIPA standards so that ideally Jade agents could interact with agents written in other languages and running on other platforms. From the view of message content, there are three ways to implement communication between agents. This paper mainly did some research on how to implement communication between Jade agents using serialized Java objects. Serialization is Java's built-in mechanism for transforming an object graph into a series of bytes, which can then be sent over the network or stored in a file. The research relies on the Project Supported by Innovative Research Team in University of LiaoNing Province: Maritime search and rescue decision support system based on multi-agent. The results show that in a distributed network programming, particularly for transmitting complex objects in multi-agent systems, the use of object serialization is very flexible. But it is also very limited. It must store and retrieve the entire object graph at once, making it unsuitable for dealing with large amounts of data.

Abstract: It is very important to take into consideration time delay in wide area power system stability; the design of PSS (Power System Stabilizer) should consider global optimization with WAMS (Wide Area Measurement System) time delay. Newly designed PSS should be insensitive to time delay and suppress internal low frequency oscillations. It is used as feedback signal and is real-time synchronous that WAMS signal shows. Power system is modeled with the consideration of time delay. LMI (Linear Matrix Inequalities) is used to solve the stability condition of time delay system. Based on the time-delay effect of the wide-area measurement signals, this paper redesigned the PSS with global optimization of power system. The attached two-area-four-machine system simulation illustrates that wide-area PSS designed by global optimization with the consideration of time-delay can limit internal low frequency oscillation with time-delay insensitivity, and improve the stability of power system. It implements global optimization of PSS with WAMS time delay stability.

Abstract: The limitations of empiric design methods for amplifier biasing stability were pointed out. Critical bias and output range of voltage divider biasing amplifier were discussed. The relationship between bias temperature coefficient and β temperature coefficient was discussed as well. The ratio of bias temperature coefficient to β temperature coefficient is defined as effecting factor. Amplifier bias stability is designed based on output range temperature coefficient. The methods for designing base biasing resistance of voltage divider biasing amplifier on the basis of output range temperature coefficient and for analyzing biasing stability of this amplifier are introduced.

Abstract: Base on constitution of the self-oscillation linear actuator which is a servo system for a gun launched missile, a nonlinear model was built. Though the experiment, the model is correct. This paper studied the stability, the self-oscillation's frequency and gain on this kind of servo system. On comparing phase-lead compensation and phase-lag compensation, the later is more suitable for this system. After testing, the lag regulator is designed for the system.

Abstract: This paper investigates the characteristics of the switching transients between the grid-connected and the autonomous modes for an inverter-based microgrid. The impact of the microgrid components including system line, load and inverter controller on the switching transients is analyzed through electromagnetic transient simulations. A soft switching scheme is also proposed in this paper to improve the microgrid switching performance.