Single-phase ac–dc wireless power transfer (WPT) converters are widely used in grid-connected systems, such as wireless electric vehicle chargers. Traditional two-stage topology with an ac–dc power factor correction (PFC) rectifier stage and a dc–dc WPT converter stage cannot achieve the highest overall efficiency and the lowest production cost. Moreover, two separate controllers are required. Recently, a single-phase single-stage ac–dc WPT converter with a front-end boost bridgeless PFC rectifier was proposed to overcome the drawbacks of two-stage topologies. However, two front-end diodes are still required for rectification, and the input power quality is not sufficiently high as the input current is not actively shaped. In this article, a compact single-phase integrated-power-stage ac–dc WPT converter with only four active power switches and four diodes is proposed. The full-bridge switches are utilized to perform ac–dc PFC rectification and dc–dc WPT conversion simultaneously. Description of the proposed topology with the modulation and control methods, operation principle, power loss analysis, and referenced design procedure are presented in detail. Finally, a 500-W laboratory prototype is implemented, and the corresponding experimental results are given to validate the principle, analysis, and design.

Bidirectional ac–dc wireless power transfer (WPT) converters are widely used in grid-connected electric vehicle systems for grid-to-vehicle and vehicle-to-grid applications. They usually apply a two-stage topology with a bidirectional ac–dc power factor correction converter and a bidirectional dc–dc WPT converter. Such a two-stage topology cannot achieve high efficiency and low cost. Recently, single-stage matrix bidirectional ac–dc WPT converters have been proposed. However, the matrix-converter-based topologies do not utilize remarkably lower count of power switches and generate large double-line frequency ripple in the dc-side voltage or current. This article proposes a new single-phase bidirectional ac–dc WPT topology with an integrated power stage to overcome the drawbacks of the matrix-converter-based topologies and retain the advantages of single-stage topologies. Description of the proposed topology with the modulation and control methods, theoretical analysis, and reference design procedure are presented in detail. Finally, a scaled-down laboratory prototype with 500-W output power is implemented with experimental results presented to validate the principle, analysis, and design.

A transient control for a dual‐active‐bridge (DAB) dc/dc converter to realise power adjustment in a fast and smooth way is proposed. The converter is able to transfer power between two dc sources with two phase‐shifts as control variables. To eliminate the possible high‐current overshoot and non‐zero dc‐bias current, the adjustments of the two phase‐shifts are distributed to the gating signals of different switch arms according to a ratio x , which has an universal expression for any transitions among different operation modes in a DAB converter. Experimental results have proved the validity of the proposed transient control in elimination of current overshoot and dc‐bias current.

Linear extended state observer (LESO) plays a critical role in ADRC's control performance. However, there exists a tradeoff between disturbance rejection and noise immunity for traditional linear ESO (TLESO). Compared to TLESO with similar bandwidth, phase-locking loop observer (PLLO) exhibits a better output tracking performance but weaker noise suppression capability. By combining the advantages of TLESO and PLLO, an adaptive LESO (ALESO) is proposed in this article, which utilizes TLESO in steady state and PLLO during transient state. The dynamic and noise-suppression performances of different observers are analyzed and compared systematically. The proposed ALESO inherits good dynamic response of PLLO and noise-suppression performance of TLESO, without using high bandwidth. It also possesses the advantages of simple structure, requiring few tuning parameters and ease of parameter tuning. To verify the feasibility and effectiveness of the proposed ALESO design, it is employed to a 500 W dual-active-bridge dc–dc converter for pulsed power applications. Experiments results show that, in comparison with TLESO, the proposed ALESO has resulted in 33.3%/37% and 60%/73.3% reductions in output voltage undershoot/overshoot and setting time, respectively, under load step-up/down. For steady-state performance, a noise level reduction of 76.3% is achieved compared to that resulting from PLLO.

The dynamics of nonresonant dual-active-bridge converter (DABC) are simultaneously affected by the transient modulation strategy and controller design. In general, inappropriate transient modulation strategies can lead to nonzero transient dc offsets in the inductor current and transformer’s magnetizing current, thus introducing excessive trajectory tracking error and time delays between the pulsewidth modulation generator and controller. Consequently, truly optimal transient responses cannot be achieved solely through a high-performance controller, unless the modulation-induced transient dc offsets can be completely eliminated. This article presents a comprehensive review of the optimized transient phase-shift modulation (OTPSM) strategies for single-phase-shift modulated DABC, and derives a novel optimal modulation method referred to as symmetric single-sided OTPSM (SS-OTPSM), which is based on a unified theoretical framework of OTPSM and an additional condition enabling a full elimination of all undesired transient dc offsets. The proposed SS-OTPSM can be easily and cost-effectively implemented in a cycle-by-cycle manner, and inherently compatible with fast controllers. Additionally, in order to more accurately match DABC’s power transfer model under SS-OTPSM, an enhanced model predictive controller (EMPC) is proposed. By a combined use of SS-OTPSM and EMPC, ultrafast and completely dc-offset-free dynamics can be achieved without measuring the inductor current. The effectiveness of the proposed schemes is verified by closed-loop simulation and experimental results.

The increasing penetration of distributed renewable generations has given rise to a novel energy management mechanism, peer-to-peer (P2P) energy trading. The concept of Energy Internet (EI) is proposed as a new energy system framework to facilitate P2P energy trading where all distributed electrical devices are interconnected via energy routers (ERs). A proper market clearing approach is required to coordinate decentralized decision making in P2P market for demand-supply balance and feasible end-to-end energy delivery. In this paper, a decentralized market clearing mechanism considering energy path conflict management is proposed for P2P energy trading in energy local area network (e-LAN). An adjusted conflict-based search (ACBS) algorithm is proposed to deal with the non-convexity of the social welfare maximization problem where the nonconvex problem is transformed into multiple independent convex problems. Considering the privacy protection of participants, a dual decomposition based approach is proposed to solve these convex problems in a decentralized manner where self rationality of each participant can be satisfied by maximizing its personal welfare. In addition, energy path conflicts caused by decentralized optimization is resolved by imposing penalty fee and observing the rule of energy sharing maximization. Numerical simulations are presented to verify the effectiveness of the proposed market clearing approach.