This short note points out an improvement on the robust stability analysis for electrically driven robots given in the paper. In the paper, the author presents a FAT-based direct adaptive control scheme for electrically driven robots in presence of nonlinearities associated with actuator input constraints. However, he offers not suitable stability analysis for the closed-loop system. In other w...

in this paper, construction rules of the root locus of a positive feedback system whose loop transfer function is not strictly proper have been investigated. the root locus method is being used since 1950. it is demonstrated that some of the steps in this technique are not general and for a positive feedback system whose loop transfer function is not strictly proper are not valid. to overcome t...

in this paper a new strategy is proposed to design a fixed-structure robust controller for a flexible beam.  robust controller designed by the conventional  loop­ shaping method is not appropriate for a beam because of its high order and complicated form. fixed-structure  loop shaping control in conjunction with particle swarm optimization (pso)algorithm  is used to overcome this drawback. the ...

this paper is concerned with the problem of designing discrete-time control systems with closed-loop eigenvalues in a prescribed region of stability. first, we obtain a state feedback matrix which assigns all the eigenvalues to zero, and then by elementary similarity operations we find a state feedback which assigns the eigenvalues inside a circle with center   and radius. this new algorithm ca...

New methods, for the design of different block diagrams of PLL, using the asymptotic analysis of high-frequency periodic oscillations, are suggested. The PLL description on three levels is made: 1) on the level of electronic realizations; 2) on the level of phase and frequency relations between inputs and outputs in block diagrams; 3) on the level of differential and integro-differential equati...

with increasing the presence of microgrids (mgs) in the power systems, investigating the mg stability during transient faults is necessary. this study investigates the transient stability analysis of a mg supplied by multiple inverter interfaced distributed generations (iidgs) during fault. the transient stability of a mg is highly depends on the iidgs control strategy. a mg, simulated on matla...

a new approach for pole placement of nonlinear systems using state feedback and fuzzy system is proposed. we use a new online fuzzy training method to identify and to obtain a fuzzy model for the unknown nonlinear system using only the system input and output. then, we linearized this identified model at each sampling time to have an approximate linear time varying system. in order to stabilize...