A study on the optimal voltage regulation methods in power distribution systems interconnected with dispersed energy storage and generation systems
This paper deals with optimal voltage regulation methods in power distribution systems including dispersed energy storage and generation (DSG) systems. In order to deliver suitable voltages to as many customers as possible, optimal sending voltages should be decided by the effective operation of voltage regulators at distribution substations. In this paper, optimal voltage regulation methods are presented based on statistical analysis considering the customer voltage conditions and operation characteristics of DSG systems. Optimal operation methods of multiple voltage regulators are also suggested. In addition, the introduction impacts of DSG systems such as optimal location sites and introduction capacity are evaluated.
Aging effect degrades circuit performance in the runtime, interacts with fabrication-induced device parameter variation, and thus posing significant impact on circuit lifetime reliability. In this work, a statistical circuit optimization flow is proposed to ensure lifetime reliability of the manufactured chip in the presence of process variation and aging effects. It exploits a variation-aware gate-level statistical aging degradation model to characterize circuit lifetime reliability, identifies a set of worst duty cycles on the inputs of statistically critical gates to estimate the worst delay degradations on these gates. Based on the delay degradation information, statistical gate sizing is performed which enables the manufactured chip to satisfy lifetime reliability constraint in term of low area overhead.