Ghada Boukettaya

Improving grid connected hybrid generation system supervision with sensorless control

In this paper, speed identification and control problems are simultaneously considered for a micro-grid power generation system (MG-PGS). To eliminate mechanical sensors, an observer has been designed to identify the speed of a wind energy conversion system based on a permanent magnet synchronous machine (PMSM). The proposed observer is an adaptive interconnected structure with online parametric estimation. Moreover, a new control based on the Lyapunov theory has been developed in order to improve sensorless control of a flywheel energy storage system based on induction machine. In fact, the main idea of this control technique is based on an appropriate choice of voltage control values that guaranty the global stability of the controlled system. Simulation results indicate that the sensorless control applied to the MG-PGS improves performances of the global control. The PMSM mechanical speed, the stator resistance, and inductance could be estimated precisely, and the dynamical property of the system is ob...

A vector control of a cascaded doubly fed induction generator for a wind energy conversion system

This paper presents a study developed about variable speed wind turbine system based on doubly fed twin stator induction machine (DFTSIG). In this paper we discuss the different architectures of the cascaded DFTSIG, in the case of direct coupling and indirect coupling. The wind generators modeling and control are presented; we have chosen a model with direct oriented vector control to ordering the power exchange between the machine stator controlled via a bidirectional converter. This control is developed and tested by synthesizing proportional integrator regulator.

Demand side management of an isolated hybrid energy production unit supplying domestic loads

The purpose of this article is to develop a demand side management (DSM) of an isolated hybrid unit (IHU) supplying domestic loads. The action on load profile provides an efficient way to improve the energy management system associated to an autonomous smart home. This domestic IHU comprises a photovoltaic (PV) panel as principal source, a diesel engine as a buckup source and a storage system. Indeed, the action on some controllable loads can fully benefit from the renewable power and achieve savings and higher efficiency in energy consumer. In fact, the DSM algorithm uses the customer energy history, the available instantaneous PV energy and the state of charge of the storage system to switch between two appropriate modes: time shifting load mode and amplitude modulation load one. This management technique allows the consumer to minimize the installation initial cost and to extend the lifetime of system components. Simulation results show the effectiveness of the proposed DSM strategy.

Power management of an isolated hybrid energy production unit with super-capacitor

The aim of this paper is to propose a power control strategy of an isolated hybrid energy production unit. The proposed (wind / photovoltaic / diesel / super-capacitor) hybrid system is found to be the configuration to ensure a continuous feed of a three-phase load and to secure the storage system. An overall power management strategy is designed to manage power flows between the different energy sources and the storage unit. In this context, we used a control algorithm which describes four operating modes. The obtained simulation results are presented and discussed and the control strategy is validated for different scenarios.

Action on the dynamic behavior of a washing machine in a renewable multi-agent system

This paper investigates the action on the dynamic behavior of a domestic washing machine in a multi-agent system. The purpose of this work is to develop a demand side management control strategy by modifying the washer power profile. This strategy leads to increase the renewable energy usage and to reduce peak demands by modifying the electrical profile of the consumer.

Sliding mode control for induction machine based on the Lyapunov theory

In this paper, we develop a new control approach for IM. The IM mechanical speed variable perfectly follows its references through a PI controller based on the sliding mode. The associate PI gains of the flux regulator are calculated by pole placement method. The basic idea of this technic is to make stable the closed loop system in the sense of Lyapunov. This method compared with traditional IM control use a simple calculation by the fact that we obtain a global asymptotic stability. The objective of this control technic is based on an appropriate choice of the voltage control values that guaranty a global stability of the closed loop system.

Observation of IM mechanical speed Comparative study of a high gain interconnected observer and an adaptive observer

In the context of a more detailed knowledge of nonlinear observers, we become interested in studying the behavior of the speed error of the induction machines for various function regimes. The aim of this work is the comparison between two types of observers applied to the induction machine to allow the proper selection of the solution. The observers selected are the adaptive observer and the interconnected observer.

A new control technic for induction machine based on the Lyapunov theory

In this paper, we develop a new control approach for IM. The basic idea of this technic is to make stable the closed loop system in the sense of Lyapunov. This method compared with traditional IM control use a simple calculation by the fact that we obtain a global asymptotic stability. The objective of this control technic is based on an appropriate choice of the voltage control values that guaranty a global stability of the closed loop system. The IM mechanical variables perfectly follow their references through two PI controllers. The associate PI gains are calculated by pole placement method.