基于WOA-ESN的电机系统混沌振荡预测

提出一种将鲸鱼优化算法(WOA)与回声状态网络算法(ESN)结合的WOA-ESN预测方法, 并将此方法应用到永磁同步电机(PMSM)的混沌振荡预测, 进行实验仿真并和其他预测算法比较, 证明所提出方法拥有更高的预测精度。     

对有限域上复合变换的线性逼近

本文解决了有限交换群上复合函数的特征谱的计算问题,定义了有限交换群上函数的相关 系数的概念,并解决了有限域上复合函数与线性映射的相关系数的计算问题,从而建立了对密码算 法中的复合变换进行线性逼近的理论基础.     

Chaos in complex motor networks induced by Newmanben Watts small-world connections

We investigate how dynamical behaviours of complex motor networks depend on the Newman-Watts small-world (NWSW) connections. Network elements are described by the permanent magnet synchronous motor (PMSM) with the values of parameters at which each individual PMSM is stable. It is found that with the increase of connection probability p, the motor in networks becomes periodic and falls into chaotic motion as p further increases. These phenomena imply that NWSW connections can induce and enhance chaos in motor networks. The possible mechanism behind the action of NWSW connections is addressed based on stability theory.     

Lattice Boltzmann Simulation for Complex Flow in a Solar Wall

In this letter,we present a lattice Boltzmann simulation for complex flow in a solar wall system which includes porous media flow and heat transfer,specifically for solar energy utilization through an unglazed transpired solar air collector(UTC).Besides the lattice Boltzmann equation(LBE) for time evolution of particle distribution function for fluid field,we introduce an analogy,LBE for time evolution of distribution function for temperature.Both temperature fields of fluid(air) and solid(porous media) are modeled.We study the effects of fan velocity,solar radiation intensity,porosity,etc.on the thermal performance of the UTC.In general,our simulation results are in good agreement with what in literature.With the current system setting,both fan velocity and solar radiation intensity have significant effect on the thermal performance of the UTC.However,it is shown that the porosity has negligible effect on the heat collector indicating the current system setting might not be realistic.Further examinations of thermal performance in different UTC systems are ongoing.The results are expected to present in near future.     

代数次数为3的6元3维Bent函数的结构分析

Rothaus在其文章《On Bent Functions》中指出代数次数为3的6元Bent函数只有3个等价类．本文则推导出代数次数为3的6元Bent函数各等价类中函数的具体结构形式,并由此给出了以任意一个代数次数是3的6元Bent函数为分量的多维Bent函数的构造法．     

Random-phase-induced chaos in power systems

This paper studies how random phase (namely, noise-perturbed phase) effects the dynamical behaviours of a simple model of power system which operates in a stable regime far away from chaotic behaviour in the absence of noise. It finds that when the phase perturbation is weak, chaos is absent in power systems. With the increase of disturbed intensity $\sigma$, power systems become unstable and fall into chaos as $\sigma$ further increases. These phenomena imply that random phase can induce and enhance chaos in power systems. Furthermore, the possible mechanism behind the action of random phase is addressed.     

分布式发电系统感性负载的远程混沌同步

对含有大规模感性负载分布式发电系统（DG）的远程同步进行研究.以风力发电机作为DG发电节点,以永磁同步电机作为实际感性负载,建立一个具有网络耦合作用的DG数学模型,分析不同拓扑网络结构（包括星型、多层网络结构型、随机网络结构型、实际电网IEEE39系统）DG系统感性负载的远程同步特性,进行数值仿真.研究表明：感性负载通过发电机组的中继作用可实现远程混沌同步.研究结果对保证分布式发电系统的同步稳定运行具有意义.     

温度对吡啶离子液体性质影响的分子动力学模拟研究

运用分子动力学模拟方法研究了温度对三种吡啶离子液体[BPy][BF4]、[HPy][BF4]、[OPy][BF4]热力学性质的影响, 得到了每个体系的密度、自扩散系数、电导率和黏度等. 研究结果表明: 随着温度升高, 同一种离子液体的密度减小, 阴阳离子的自扩散系数明显增大, 电导率升高, 而黏度降低. 在同一温度下, 随着阳离子上烷基链的增长, 离子液体的密度减小, 但热力学性质的变化规律并不完全同步. 烷基链长最短的[BPy][BF4]的自扩散系数和电导率在每个温度下均为最大, 而黏度最小; 但烷基碳链更长的[OPy][BF4]和[HPy][BF4]的各种性质相差不大,甚至当温度大于323K时, 烷基链较长的[OPy][BF4]的自扩散系数比[HPy][BF4]的大.     

Passive adaptive control of chaos in synchronous reluctance motor

The performance of synchronous reluctance motor (SynRM) degrades due to chaos when its systemic parameters fall into a certain area. To control the undesirable chaos in SynRM, a passive control law is presented in this paper, which transforms the chaotic SynRM into an equivalent passive system. It is proved that the equivalent system can be asymptotically stabilized at the set equilibrium point, namely, chaos in SynRM can be controlled. Moreover, in order to eliminate the influence of undeterministic parameters, an adaptive law is introduced into the designed controller. Computer simulation results show that the proposed controller is very effective and robust against the uncertainties in systemic parameters. The present study may help to maintain the secure operation of industrial servo drive system.