Coordination control of an AC-to-DC converter and a switched excitation capacitor bank for an autonomous self-excited induction generators 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 (DSP). The aim of the proposed control scheme is to maintain a fixed DC voltage at the output terminals of the 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 outcomes and experimental results that the proposed coordination control scheme can be applied to various renewable-energy systems based on SEIG to offer an adequate DC voltage under different operating conditions.