A DC -DC converter topology is proposed. The DC -DC multilevel boost converter (MBC) is a pulse-width modulation (PWM)-based DC -DC converter, which combines the boost converter and the switched capacitor function to provide different output voltages and a self-balanced voltage using only one driven switch, one inductor, 2N 2 1 diodes and 2N 2 1 capacitors for an Nx MBC. It is proposed to be used as DC link in applications where several controlled voltage levels are required with self-balancing and unidirectional current flow, such as photovoltaic (PV) or fuel cell generation systems with multilevel inverters; each device blocks only one voltage level, achieving high-voltage converters with low-voltage devices. The major advantages of this topology are: a continuous input current, a large conversion ratio without extreme duty cycle and without transformer, which allow high switching frequency. It can be built in a modular way and more levels can be added without modifying the main circuit. The proposed converter is simulated and prototyped; experimental results prove the proposition's principle.

No abstract

This work proposes a novel controller in a stationary reference frame for permanent magnet synchronous generator (PMSGs) of grid-connected wind turbines. The wind energy conversion systems (WECS) adopt a Back-To-Back converter system with voltage source inverter (VSI) and a phaselocked loop to track continuously the fundamental frequency and its phase from voltage node that is connected to the system generation. One of the central themes of this paper is the development of a control scheme that uses a B-spline artificial neural network for controllers tuning when the system is subjected to disturbances. The B-spline neural network must be able to enhance the system performance and the online parameters updated can be possible. This work proposes the use of adaptive PI controllers to regulate the current, frequency and DC-link voltage. Results of the dynamic behavior of the whole WECS are presented along with different cases subject to various disturbances. The simulations show the feasibility and robustness of the proposed control schemes for PMSG based wind turbines. 2002. His current research interests are in modeling and control of wind energy systems and motor drives with computational intelligence techniques.

No abstract

No abstract