The motor speed of a buck power converter and DC motor coupled system is controlled by means of a quasi-sliding scheme. The fixed point inducting control technique and the zero average dynamics strategy are used in the controller design. To estimate the load and friction torques an online estimator, computed by the least mean squares method, is used. The control scheme is tested in a rapid control prototyping system which is based on digital signal processing for a dSPACE platform. The closed loop system exhibits adequate performance, and experimental and simulation results match.

A fifth-order dynamic continuous model of a linear induction motor (LIM), without considering “end effects” and considering attraction force, was developed. The attraction force is necessary in considering the dynamic analysis of the mechanically loaded linear induction motor. To obtain the circuit parameters of the LIM, a physical system was implemented in the laboratory with a Rapid Prototype System. The model was created by modifying the traditional three-phase model of a Y-connected rotary induction motor in a d–q stationary reference frame. The discrete-time LIM model was obtained through the continuous time model solution for its application in simulations or computational solutions in order to analyze nonlinear behaviors and for use in discrete time control systems. To obtain the solution, the continuous time model was divided into a current-fed linear induction motor third-order model, where the current inputs were considered as pseudo-inputs, and a second-order subsystem that only models the currents of the primary with voltages as inputs. For the discrete time model, the current-fed model is discretized by solving a set of differential equations, and the subsystem is discretized by a first-order Taylor series. Finally, a comparison of the continuous and discrete time model behaviors was shown graphically in order to validate the discrete time model.

To analyze the performance of the PID controller in a buck type converter implemented in real time. We begin by designing a continuous controller using the analytical method for calculating PIDs. Pulse width modulation is then used and bifurcation diagrams analyzed to reveal some problems of switching and sampling time. The model converter is then implemented with a PID controller in dSPACE. The experimental results provide detailed requirements of sampling frequency and switching speed, and show the performance of the PID controller. Converters are used in power generation solar systems and conmuted power sources for feed telecommunication devices, smart grids, and other applications.

In this paper we present a new algorithm to generate the reference signals to control the series and parallel power inverters in an unified power quality conditioner “UPQC” to enhance power quality. The algorithm is based in the instantaneous power tensor formulation which it is obtained by the dyadic product between the instantaneous vectors of voltage and current in n-phase systems. The perfect harmonic cancelation algorithm “PHC” to estimate the current reference in a shunt active power filter was modified to make it hardy to voltage sags through unit vector template generation “UVGT” while from the same algorithm it extracts the voltage reference for series active power filter. The model was validated by mean of simulations in Matlab-Simulink®.

This paper presents a stability analysis of a buck converter using a Zero Average Dynamics (ZAD) controller and Fixed-Point Induction Control (FPIC) when the control parameter 𝑁, the reference voltage υref, and the source voltage 𝐸 are changed. The study was based on a previous analysis in which the control parameter was adjusted to 𝑁=1 and the parameter 𝐾𝑠 was changed during the simulation, finding the stability zone and regions with chaotic behavior. Thus, this new study presents the transient and steady-state behaviors and robustness of the buck converter when the control parameter 𝑁 changes. Moreover, numerical simulation results are compared with experimental observations. The results show that the system regulates the output voltage with low error when the voltage is changed in the source E. Besides, the voltage overshoot increases, and the settling time decreases when the control parameter 𝑁 is augmented and the control parameter 𝐾𝑠 is constant. Furthermore, the buck converter controlled by ZAD and FPIC techniques is effective in regulating the output voltage of the circuit even when there are two delay periods and voltage input disturbances.