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The aim of this paper is to perform a simple and robust control method based on the well-known sliding control approach for a self-excited induction generator supplying an isolated DC load; this adopted technique does not require much computation and could be easily implemented in practice. In this context, the present work will begin with a mathematical development of this control technique and its application to the self-excited induction generator case. For this purpose, the machine provides the produced active power to the load through a static PWM converter equipped with a single capacitor on the DC side. In order to insure the output DC-bus voltage regulation with respect to the load-power demands and the rotor speed fluctuations, the required stator currents references are computed by considering the reactive power required for the machine core magnetization, the induced voltages through the stator windings and the active power set value obtained from the corresponding sliding mode DC-bus voltage controller. Regarding the nonlinearity of the DC-bus voltage mathematical model and the discontinuity characterizing the converter-machine behavior association, the sliding mode strategy will constitute a perfect tool to sizing the controller structure with high control performances. Results of simulation carried out to demonstrate the proposed control validity are presented. References 26, figures 6.

This paper proposes a novel idea to governing wind power conversion plants supplying DC loads characterizing an isolated site based on self-excited squirrel-cage induction generators (IG). In this wind power converting application, the induction generator produces an active power from the mechanical power provided by a wind-turbine to variable DC loads through a static converter with an output capacitor under constant voltage levels. For this reason, A specific vector control technique has been developed for controlling the induction machine in an analogous manner with a separated DC machine case. Thus, in order to satisfy the active power demand characterizing a variable DC load at a given rotor mechanical speed, the corresponding control laws are performed in steady-state conditions from a new control variable introduction defined by the ratio of the desired output DC-bus voltage square value and the rotor velocity. Computer simulations validated by experimental results demonstrate that the projected control approach including just one conventional controller ensures excellent tracking performances of the DC-bus voltage to its reference trajectory under simultaneous variations of the load-power demand and the rotor velocity profiles.