Methods of Improving Digital Voltage and Current Mode Control Performance in Medium Power DC/DC Converters for Satellite Applications

摘要

A digital control of a power converter in space applications has several advantages over the traditionalrnones that often suffer from undesirable SEE, aging and controller’s elements’ parameters drifts due tornchanges in operating conditions. Unfortunately, digital converters very often experience lack of bandwidthrnbecause of inherent delay between a measurement of a voltage or current levels and appliedrncontrol effort. This delay introduces a sharp phase roll-off that can lead to system oscillation or instability.rnThe delay can be minimized by introduction some prediction, that results in a large burden of computation.rnOther method that is based on making measurements as close as possible to the end ofrneach switching cycle is presented in this paper. Another possible way to improve digital converter isrnimplementing switching of controller’s parameters on a boundary between CCM and DCM modes. Thernresults of the work on above methods are presented.