Pablo Federico Puleston

Sliding Mode Strategy for PEM Fuel Cells Stacks Breathing Control Using a Super-Twisting Algorithm

A second-order sliding mode strategy to control the breathing subsystem of a polymer electrolyte membrane fuel cell stack for transportation applications is presented. The controller is developed from a design model of the plant derived from open literature, and well suited for the design of second-order sliding mode strategies. Stability issues are solved using a super twisting algorithm. The resulting approach exhibits good dynamic characteristics, being robust to uncertainties and disturbances. Simulations results are provided, showing the feasibility of the approach.

Lyapunov-Designed Super-Twisting Sliding Mode Control for Wind Energy Conversion Optimization

This work explores an adaptive second-order sliding mode control strategy to maximize the energy production of a wind energy conversion system (WECS) simultaneously reducing the mechanical stress on the shaft. Such strategy successfully deals with the random nature of wind speed, the intrinsic nonlinear behavior of the WECS, and the presence of model uncertainties and external perturbations acting on the system. The synthesized adaptive controller is designed from a modified version of the super-twisting (ST) algorithm with variable gains. The suitability of the proposed strategy is proved by extensive computer-aided simulations employing a comprehensive model of the system emulating realistic conditions of operation, i.e., considering variations in the parameters and including external disturbances. Additionally, a second controller based on the traditional ST algorithm is also designed and simulated. Results are presented and discussed in order to establish a comparison framework.

Power control of a solar/wind generation system without wind measurement: a passivity/sliding mode approach

This paper deals with the control of the output power of a solar/wind stand-alone system. The control system regulates the generation of the wind subsystem in order to satisfy, jointly with the photovoltaic generation subsystem, the load and battery charge power demand. The controller is designed using a theoretical framework that unifies passivity and sliding mode techniques. The resultant control law does not need wind measurement and only relies on rotational speed and current measurements. An analysis of the acceleration estimate error is carried out and a countermeasure to compensate its effects is proposed. Finally, the performance of the controller is assessed through computer simulation, using a comprehensive nonlinear model of the plant.

A wind turbine emulator based on a dual DSP processor system

Abstract In this paper the principles and structure of a wind turbine emulator (WTE) are described. The WTE is a versatile system specially designed for the purpose of developing and testing new control strategies for wind energy conversion systems. The WTE is built around a processor module, which controls a separately-excited DC motor. The core of the processor module is a dual DSP system working in a tightly-coupled architecture. The WTE provides a friendly environment to readily modify wind speed conditions, change turbine parameters and supervise system variables. Experimental results from the WTE coupled to a grid-connected induction generator are analyzed.

Active and Reactive Power Control for Wind Turbine Based on a MIMO 2-Sliding Mode Algorithm With Variable Gains

This study proposes a power control strategy for a grid-connected variable-speed wind turbine, based on a doubly-fed induction generator (DFIG) with slip power recovery. The control objectives vary with the zones of operation (dependant on the wind speed), aiming to maximize the active power in the partial load zone and to limit it when operating within the full load zone, while regulating the stator reactive power following grid requirements. The control design, based on the second-order sliding modes (SOSM) and Lyapunov, uses a modified version of the super-twisting algorithm with variable gains which can be applied to nonlinear multiple inputs-multiple outputs (MIMO) systems. The well-known robustness of the sliding techniques, the simplicity of the algorithm, and the adaptive characteristic of its gains are used together in this study to obtain a controller able to deal robustly with the exacting challenges presented by these systems. An additional benefit of the proposal lies in the smoothness of the control action, an important issue regarding applied mechanical efforts. Representative results obtained by simulation of the controlled system are shown and discussed.

Sliding-mode control of PEM fuel cells

Introducing Fuel Cells.- Basics of PEM Fuel Cells.- Fundamentals of Sliding Mode Control Design.- Assessment of SOSM Techniques Applied to Fuel Cell Control.- Control-oriented Modelling and Experimental Validation of a PEMFC Generation System.- SOSM Controller for the PEMFC Generation System: Design and Implementation.- Closing Remarks.

An adaptive feedback linearization strategy for variable speed wind energy conversion systems

This paper presents a control strategy based on adaptive feedback linearization intended for variable speed grid-connected wind energy conversion systems (WECS). The proposed adaptive control law accomplishes energy capture maximization by tracking the wind speed fluctuations. In addition, it linearizes the system even in the presence of turbine model uncertainties, allowing the closed-loop dynamic behaviour to be determined by a simple tuning of the controller parameters. Particularly, the attention is focused on WECS with slip power recovery, which use a power conversion stage as a rotor-controlled double-output induction generator. However, the concepts behind the proposed control strategy are general and can be easily extended to other WECS configurations. Copyright

Sliding mode control for efficiency optimization of wind energy systems with double output induction generator

This paper deals with generation efficiency maximization of wind energy conversion systems (WECS) with double output induction generator (DOIG). In the first place, to design a sliding mode controller, an apropos model of the DOIG with electronic drive in the rotor is developed. Then, conditions of maximum power generation are obtained. Finally, a sliding mode control strategy for this type of WECS is presented. The proposed strategy varies the firing angle of the electronic drive in order to set the extreme control values equal to the maximum and minimum available control action of the system. Consequently, robustness to parametric uncertainties and external disturbances is maximised.

Experimental results on smooth path tracking with application to pipe surveying on inexpensive AUV

This paper details the development aspects of a low cost AUV autonomous, designed for autonomous pipline inspections, describing: hardware, software and control aspects. The article details three of the mains stages of the project, that have been already achieved: (a) the simulation results of Lyapunov based path planning of torpedo shaped AUV on pipe searching; (b) the construction details of dual torpedo AUV for pipeline inspection and (c) the experimental results when using the prototype in path following using the line of sight (LOS) algorithm.

A Wind Turbine Emulator Based on a Dual DSP Processor System

Abstract In this paper the principles and structure of a wind turbine emulator (WTE) are described. The WTE is a versatile system specially designed for the purpose of developing and testing new control strategies for wind energy conversion systems. The WTE is built around a processor module, which controls a separately-excited DC motor. The core of the processor module is a dual DSP system working in a tightly-coupled architecture. The WTE provides a friendly environment to readily modify wind speed conditions, change turbine parameters and supervise system variables. Experimental results from the WTE coupled to a grid-connected induction generator are analyzed.