Nonlinear Controller for the Set-Point Regulation of a Buck Converter System

In this paper, we present a nonlinear PID controller based on saturation functions with variable parameters in order to regulate the output voltage of a buck converter in the presence of changes in the input voltage. The main feature of the proposed controller is to bound the control input with a variable parameter to avoid the windup effect generated by the combination of the integral control action and some operation conditions. The main advantages of the proposed nonlinear PID controller are its low computing cost and the simple tuning task to implement the control strategy in an embedded system. The acceptable behavior of the closed-loop system is presented through the simulation and experimental results

Fourier Analysis for Harmonic Signals in Electrical Power Systems

The harmonic content in electrical power systems is an increasingly worrying issue since the proliferation of nonlinear loads results in power quality problems as the harmonics is more apparent. In this paper, we analyze the behavior of the harmonics in the electrical power systems such as cables, transmission lines, capacitors, transformers, and rotating machines, the induction machine being the object of our study when it is excited to nonsinusoidal operating conditions in the stator winding. For this, a model is proposed for the harmonic analysis of the induction machine in steady‐state regimen applying the Fourier transform. The results of the proposed model are validated by experimental tests which gave good results for each case study concluding in a model proper for harmonic and nonharmonic analysis of the induction machine and for “harmonic” analysis in an electrical power system

Power Quality in Renewable Energy Microgrids Applications with Energy Storage Technologies: Issues, Challenges and Mitigations

Nowadays, the electric power distribution system is undergoing a transformation. The new face of the electrical grid of the future is composed of digital technologies, renewable sources and intelligent grids of distributed generation. As we move towards the electrical grid of the future, microgrids and distributed generation systems become more important, since they are able to unify small-scale and flexible generation to clean energy and intelligent controls. The microgrids play an important role in marking electrical grids more robust in the face of disturbances, increasing their resilience. Although the microgrid concept continues in discussion in technical circles, it can be defined as an aggregation of electrical elements in low generation voltage, storage and loads (users) which are grouped in a certain bounded geographical area. The issues of a microgrid integrated with energy storage technologies has gained increasing interest and popularity worldwide as these technologies provide the reliability and availability that are required for proper operation in the system. Actual studies show that the implementation of energy storage technologies in a microgrid improves transients, capacity, increases instantaneous power and allows the introduction of renewable energy systems. However, there are still certain unsolved problems in power quality terms. This article clearly describes those problems generated by each storage technology foe microgrids applications. All the ideas in this review contribute significantly to the growing effort towards developing a cost-effective and efficient energy storage technology model with a long-life cycle for sustainable implementation in microgrids