This paper provides an exhaustive analysis of the Dual-Active-Bridge with Triple-Phase-Shift (DAB-TPS) modulation and other simpler ones, identifying all the possible switching modes to operate the DAB in both power flow directions, and for any input-to-output voltage range and output power. This study shows four cases and seven switching modes for each case when the energy flows in one direction. That means that the DAB operates up to fifty-six different switching modes when the energy flows in both directions. Analytical expressions for the inductor current, the output power, and the boundaries between switching modes are provided for all cases. Additionally, the combination of control variables to achieve Zero-Voltage-Switching (ZVS) or Zero-Current-Switching (ZCS) is provided for each case and switching mode, by showing which switching modes obtain ZVS or ZCS for the whole power range and all switches—independent of the input-to-output voltage ratio. Therefore, the most interesting cases, switching mode and modulation for using the DAB are identified. Additionally, experimental validation has been carried out with a 250 W prototype. This analysis is a proper tool to design the DAB in the optimum switching mode, reducing the RMS current and achieving to increase efficiency and the power density.

A new non-isolated dc–dc converter with non-inverting output and buck–boost operation, named magnetically coupled buck–boost bidirectional (MCB ³ ) converter, is presented in this article. The MCB ³ passive components arrangement connects the input and output ports getting an equivalent behavior to that of the dual active bridge (DAB) converter, but in a non-isolated topology. This equivalency allows applying Triple Phase Shift (TPS) modulation to MCB ³ . TPS is known to minimize conduction losses and to achieve soft switching at any load in the DAB converter. Throughout the article, the features of the DAB converter are used as a reference to show the main features of the proposed converter. Moreover, other modulation strategies based on TPS modulation are used in MCB ³ to operate within the minimum losses path. The multiple operation modes found on the MCB ³ under TPS modulation are identified, classified, and used to find the operating points that minimize the switching and conduction losses over the power range. The analysis is shown for the boost mode that is the worst case design. MCB ³ and DAB topologies are designed and simulated for the same specification to validate the theoretical study. Finally, experimental measurements on 460-W prototypes for both topologies corroborate the equivalent operation and the main features of the MCB ³ .

A new nonisolated bidirectional dc–dc converter with noninverting output and buck–boost operation is proposed and described in this article. The passive components arrangement in the proposed magnetically coupled buck–boost bidirectional dc–dc (MCB ³ ) converter makes it possible to use triple-phase shift (TPS) modulation, originally intended for the classical dual active bridge (DAB) converter. TPS allows the MCB ³ converter to achieve soft switching and conduction losses minimization for any load and voltage requirement. In this article, the mathematical analysis of the proposed converter operation is shown for the step-up operation, which is the worst-case design. The multiple operation possibilities that allow the use of the three TPS control variables are identified, classified, and used to find the operating points that minimize the power losses for any voltage and power range. Besides, the theoretical study demonstrates that MCB ³ converter operation is equivalent to that in the classical DAB converter; thus, the DAB converter know-how can be employed in the proposed converter, but for nonisolated applications. MCB ³ converter feasibility is validated by comparing the simulation-level results to the experimental measurements for a 460-W-scaled prototype.

How do UK local authorities contribute to national carbon reductions? Urban energy and carbon models are emerging as a vital tool for local authorities that wish to understand the greenhouse gas emissions of their city and how to reduce them. The linkage between policy processes and tools is rarely recognized and tools are deployed ad hoc. A set of policy-relevant assessment criteria is proposed and used to review the emergent state-of-the-art in UK urban energy and carbon modelling. Drawing on the authors' own experience and the literature, a differentiation is made between accounting-style inventory tools and policy modelling tools. It is argued that although part of the same overall policy process, these two approaches lack consistency in methods and implementation. A comparison with local air pollution modelling makes this contrast apparent. A lack of clarity exists for the use of modelling in urban energy and carbon policy processes. A normalized urban modelling practice would ensure consistency while preserving local flexibility. Comment les autorités locales britanniques contribuent-elles aux réductions de carbone au niveau national? Les modèles d'énergie urbaine et de carbone apparaissent comme constituant un outil essentiel pour les autorités locales qui souhaitent comprendre les émissions de gaz à effet de serre de leur ville et la manière de les réduire. Il est rarement reconnu qu'il existe un lien entre les processus des politiques et les outils, et ceux-ci sont déployés ad hoc. Il est proposé un ensemble de critères d'évaluation pertinents à l'égard des politiques concernées, utilisé pour examiner les techniques dernier cri émergentes dans le domaine de la modélisation de l'énergie urbaine et du carbone au Royaume-Uni. En s'appuyant sur l'expérience propre des auteurs et la littérature, il est établi une différenciation entre les outils d'inventaire de type comptable et les outils de modélisation des politiques. Il est soutenu que, bien que faisant partie du même processus politique global, ces deux approches manquent de cohérence quant aux méthodes et à leur mise en oeuvre. Une comparaison avec la modélisation de la pollution de l'air au niveau local rend ce contraste évident. Il existe un manque de clarté concernant l'utilisation de la modélisation dans les processus des politiques relatives à l'énergie urbaine et au carbone. Une pratique de modélisation urbaine normalisée assurerait de la cohérence tout en préservant une flexibilité au niveau local. Mots clés: cadre bâti, rréduction du carbone, rvilles, rpolitique climatique, rénergie, rautorités locales, rmodélisation, défis de la recherche