State observer based sensor less control using Lyapunov's method for boost converters

Abstract

This study proposes a state observer based sensorless controller using the Lyapunov's direct method for boost converters. The proposed controller derived from the Lyapunov method considers a large-signal model and the non-linearity of the boost converter, which allows accurate output tracking performance and stability. In addition, a state observer is constructed to estimate the inductor current using an output voltage, an input voltage and a switch control signal. The developed observer enables the proposed controller to be realised with no current sensor for the inductor current, and results in a low cost as well as reliable system free from the noise problem associated with the sensor. The non-linear controller incorporated into the observer is designed with appropriate observer gains determined by linear matrix inequalities. Experimental results are presented to verify the stable operation and output tracking capability for large-signal transients of the proposed sensorless controller based on the Lyapunov method.