Online Parameter Tuning Technique for Predictive Current-Mode Control Operating in Boundary Conduction Mode

The objective of this paper is to present an online parameter tuning technique for digital power converters with predictive peak current-mode control operating in boundary conduction mode. The issues caused by both inductor variation and input voltage drift can be solved by the proposed online parameter tuning technique which is based upon the sampled currents between two pulsewidth modulation outputs. The proposed technique requires neither an additional sensor nor a system parameter. Furthermore, the effects of inductor variation and input voltage drift are analyzed. It will be demonstrated that the variation of the inductor and input voltage drift result in a dc offset of the inductor current and deteriorate the performance. It will be confirmed by experimental results that these effects can be coped with using the presented online parameter tuning technique. Experimental results derived from a field-programmable-gate-array-based digital controller will be presented to fully confirm the theoretical analysis.