Advanced Materials Research Vols. 546-547

Abstract: This paper presents a high-precision position control system for a linear switched reluctance motor (LSRM) based on dSPACE real-time control platform. The LSRM has a very simple structure and it can be manufactured easily, and there is no need for magnets. The system utilizes dSPACE platform as the controller and generates the real-time code for the control algorithm, tuning the control parameters on line and PD algorithm is implemented. The results show that control algorithm can substantially reduce position error. The DSP-based position control scheme is implemented and experimental results prove the effectiveness of control design method.

Abstract: A high-order Iterative Learning Control (ILC) strategy is designed for Permanent Magnet Linear Motor (PMLSM). This iterative learning controller is designed to high-order open and closed loop PID-type. This paper gives the convergence conditions of the proposed controller and proves that the tracking bound is determined by the bounds of state uncertainty and output disturbance to the system. The proposed ILC strategy result shows that position precision of PMLSM in point-to-point motion can be effectively improved with this scheme. The experiments demonstrate that the presented ILC strategy is effective and robust.

Abstract: The nature of white space utilization, tremendous data processing, heterogeneous coexistence and security guarantees in Wireless Cognitive Sensor Network (WCSN) brings significant advantages over traditional Wireless Sensor Network (WSN) used in the smart grid. However, one of the main security threats to WCSN in the smart grid is the transmission of spurious data by malicious secondary users, which can induce the control center to make a wrong spectrum allocation and power dispatching decisions. In this paper, after analyzing the reference structure of smart grid and the feasibility of applying the epidemic theory into WCSN, we propose the UDG model of WCSN in the smart grid. Based on the epidemic theory in social network, we model and analyze the spurious data propagation process and identify key factors determining potential epidemic outbreaks in WCSN. In conclusion, we validate the feasibility of SIS model and perform investigations on the system dynamics.

Abstract: In this paper, based on the principle of the speed and current double closed loop DC regulating system and the requirement of the static and dynamic performance, we calculate time constant of the regulator, select the structure of the regulator to calculate related parameter and then correct its parameters, and model system and simulation by using Simulink, analysis waveform and debug to find out the optimal parameters of the system regulator to guide the actual system design.

Abstract: This article use emulation software MATLAB to design the Fast Fourier transform (FFT) algorithm. And utilize the algorithm to analyze the current frequency of power grid. This paper draws the block diagrams of the algorithm realization, and explains part of the thought of the procedures of the software realization under MATLAB environment, and also establishes the complete concept from algorithm theories to program realization. Then, analyses the harmonic component based on the procedures. Finally, comes to a conclusion that we can reduce the amplitude errors by adding the window function.

Abstract: For the problems of noise and clutter interference in the measurement of grounding resistance, the article designs a grounding resistance measurement method based on an improved FFT algorithm. We deduce the harmonic amplitude correction formula which can more accurately measure the frequency of the interference signals and the amplitude of the effective signals, and thus improve the measurement accuracy of grounding resistance. This paper also devises a grounding resistance measurement scheme combining the algorithm and the variation-frequency method. The simulation results and the validation of experimental data show that, the algorithm evidently reduces the noise and improves the measurement precision. The algorithm is of high practical value to the grounding resistance measurement.

Abstract: WSN (Wireless Sensor Networks) has been considered as one of the very promising technologies for the implementation of smart grid (SG). On the other hand, with recent advances in Cognitive Radio (CR) technology, it is possible to apply the Dynamic Spectrum Access (DSA) model in WSN to get access to less congested spectrum, possibly with better propagation characteristics. In this paper we investigate the application of WSN in smart grid and the structure of traditional WSN etc. For smart grid utility, a novel environment-adaptive and cross-layer architecture of CR-based WSN is proposed. Furthermore, the design methods, general characteristics and functions of every layer or every module are described and discussed.

Abstract: This paper is concerned about the problem of improving the service life of lithium battery and guaranteeing the safety of battery managing system (BMS) based on optimizing the process of charge, or discharge of lithium battery. Firstly, distribution method is adopted in the BMS to collect the temperature and voltage of the battery. Secondly, stage management is given to avoid over charge, or discharge of battery. Furthermore, based on LPC11C14 microprocessor, the charging device is designed. Finally, experiments are provided to show usefulness and effectiveness of the proposed methods.

Abstract: The optimal design approach of the PID controller was proposed in this paper, based on Artificial Fish Swarm Algorithm (AFSA) for the matter of the optimization of the brushless DC motor controller. In the experiment, through the analysis of the basic principles of artificial fish swarm algorithm, appropriate performance index was selected as fitness function, specific design procedures were given to optimize parameters of PID controller, The experimental results indicate that: Artificial Fish Swarm Algorithm optimized PID controller enables the brushless DC motor speed control system response faster, small overshoot, effectively improve the dynamic performance of a brushless DC motor control system.

Abstract: Large capactity of data to transmit, and geographic information of electric power facilities reflected in GIS platform as point features, linestring features and polygon features do not alway change are the general characteristics of the GIS platform, caching mechanism can significantly improve system efficiency in such information platforms. Combining these characteristics, this article studies design principles of the power GIS platform cache structure in-depth. Based on these studies, platform was built and related indicators were analyzed, some practical value were embodied.