Coordination control of an AC-to-DC converter and a switched excitation capacitor bank for an autonomous self-excited induction generator in renewable-energy systems

This paper proposes a novel coordination control scheme for effectively controlling an ac-to-dc converter and a switched excitation capacitor bank of an autonomous self-excited induction generator (SEIG) using a digital signal processor. The aim of the proposed control scheme is to maintain the dc voltage at the output terminals of the ac-to-dc converter under various operating conditions. A three-phase system model is established to simulate the dynamic performance of the studied system. The experimental results based on a laboratory 2.2-kW induction generator driven by a brushless dc motor are also carried out. It can be concluded from the simulated and experimental results that the proposed coordination control scheme can be applied to various SEIG-based renewable-energy systems based by maintaining the output dc voltage of the ac-to-dc converter under different operating conditions.