高动态特性步进电机驱动器系统设计(英文)

针对步进电机在快速加、减速及制动过程中容易出现的失步、过冲等现象,提出基于混合续流的功率器件优化导通驱动方式,能够最大程度减小在加、减速与制动过程中反电势对步进电机动态特性的影响,同时快速跟随细分电流给定波形。在此优化导通方式的基础上设计了一种具有高动态特性的全数字化步进电机驱动器,解决了步进电机在快速启停与加减速过程中出现的过冲和失步现象。实验结果表明,设计的驱动器具有很高的动态特性,符合设计要求。

基于变步融合策略求取电压稳定临界参数的研究

针对电压稳定临界参数的求取方法,以负荷导纳模型方法为基础构建了一种基于变步融合策略求取静态电压稳定临界点处参数的新方法,该策略融合了动态步进性与异步连续性两个进程。动态步进性进程体现为快速计算功率极大值点,即在增加负荷过程中跟踪计算戴维南等值阻抗,并将研究节点当前运行状态点的戴维南等值阻抗对应的导纳值作为下一状态点的负荷导纳值进行下一次计算,故可由初始状态快速、不等步地过渡到最接近临界点的功率极大值点;异步连续性进程体现为由不等步长向等步长方式的过渡且以等步长方式准确求取临界参数,即从功率极大值点开始,利用等步长增或减负荷导纳值的方式计算准确电压稳定临界参数。基于二者有效衔接,提出方向判断系数(Directional Determination Factor,DDF),从而使计算速度和精度得到了有机协调。算例IEEE30、IEEE118验证了该变步融合策略的有效性和正确性,可为研究实时在线电压稳定分析提供一种新的数据参考。

The Stepping Motion of Brownian Particle Derived by Nonequilibrium Fluctuation

The direct motion of Brownian particle is considered as a result of system derived by external nonequilibriumfluctuating. The cooperative effects caused by asymmetric ratchet potential, external rocking force and additive colorednoise drive a Brownian particle in the directed stepping motion. This provides this kind of motion of kinesin along amicrotubule observed in experiments with a reasonable explanation.

Gait fitting for snake robots with binary actuators

Thanks to the special physical architectures and various locomotion gaits,snake robots may offer significant benefits over traditional legged or wheeled locomotion designs in vast types of scenarios.This paper proposes an innovative snake robot with digitally-actuated Stewart platforms as its modules and mainly focuses on the simulations of various snake gaits.Three categories of fitting algorithms are elaborated in simulations of lateral undulation and Configuration-Fitting Algorithm of Four Modules is demonstrated as a universal gait fitting algorithm for all kinds of snake robots with binary actuators.Several typical snake gaits are simulated and the results demonstrate the excellent mobility of the snake robot.