An adaptive start-up control law for dc-to-dc converters powered from a current-limited source

This paper introduces an adaptive start-up control law for dc-to-dc converters powered from a current-limited source. This control law permits the static turn-on characteristics of the converter to be easily and accurately designed. The controller then adapts the dynamic characteristics of the converter to stay within the capabilities of the source. As a result, this adaptive control law ensures a successful system start up over a wide range of source and load conditions. In addition, the output voltage is guaranteed to increase monotonically with time. These performance features are particularly useful in distributed powering systems, because they permit a single design to serve the needs of many different applications. The expressions derived in this paper to predict the static and dynamic start-up performance of a dc-to-dc converter are shown to be in good agreement with experimental measurements. Finally, a comparison of this control law to other popular start-up techniques demonstrates the usefulness of its adaptive features.