A Variable-Frequency ZVS Modulation for Four-Switch Buck+Boost Converters with Seamless Step-up/down Mode Transition

This paper introduces variable-frequency zero voltage switching (ZVS) modulation strategy for the four-switch buck+boost converter with one operating pattern for the inductor current, i.e., three-segment inductor current modulation control. The proposed modulation scheme guarantees a smooth transition from step-up to step-down or from step-down...

Rheological Properties of High-Viscosity Modified Asphalt Containing Warm-Mix Additives

High-viscosity modified asphalt (HVMA) is the most commonly applied method in drainage asphalt pavements. However, some disadvantages of hot-mix HVMA, including high energy consumption and unavoidable environmental pollution, should be improved. Therefore, warm-mix additive (WMA) was introduced. In this paper, the effects of WMA on the...

Regeneration mechanisms of aged SBS modified asphalt from RAP materials: Molecule structure, morphology, phase transition, and interface adhesion characteristics

In this study, the environmentally friendly rejuvenators with waste thermal conductive oil, polymer, and the interfacial reinforcing agent were prepared. And the influence of the different rejuvenators on the rejuvenation mechanisms of aged SBS modified asphalt was characterized by different scales including the molecule structure, morphology...

An Improved Peak Voltage Calculation Method for Compensation Components in S-S and LCC-S Compensated Wireless Power Transfer Systems

The pursuit of battery charging technology for electric vehicle (EV) has led to extensive research on the inductive-based wireless power transfer (WPT) systems. In this paper, the compensation component (including coils) stresses will be studied in two commonly adopted compensation topologies, namely S-S and LCC-S compensations. Due to the peak...

Design of a Highly Efficient 20 kW Inductive Power Transfer System with Improved Misalignment Performance

Due to the urgent desire for a fast, convenient, and efficient battery charging technology for electric vehicle (EV) users, extensive research has been conducted into the design of high-power inductive power transfer (IPT) systems. However, there are few studies that formulate the design as a multiobjective optimization (MOO) research...

Chemo-Rheological Characterization of Aging Behaviors of Warm-Mix High-Viscosity Modified Asphalt

Today, high-viscosity modified asphalt (HVMA) is widely used in drainage asphalt pavements. However, due to its high construction temperature, HVMA is prone to thermal oxidative aging, which reduces its life cycle and increases the maintenance costs of asphalt pavements. In this study, the effects of warm-mix additives on the physical,...

Comparison of Two and Three-Level AC-DC Rectifier Semiconductor Losses with SiC MOSFETs Considering Reverse Conduction

This paper presents the semiconductor losses analytical equations in closed form for two-level voltage source converter, three-level neutral point clamped (NPC) and three-level T-Type PFC topologies in high power applications. The reverse parallel current conduction between the SiC MOSFETs channel and body diode is considered. A circuit...

Three-Mode Variable-Frequency ZVS Modulation for Four-Switch Buck+Boost Converters With Ultra-high Efficiency

This article introduces a three-mode variable-frequency zero-voltage switching (ZVS) modulation method for the four-switch buck+boost converter. This method makes this circuit concept well suited for applications, such as wireless power charging of electric vehicles, where this circuit operates as a power buffer between the resonant converter...

Sbs modified bitumen with organic layered double hydroxides: Compatibility and aging effects on rheological properties

SBS-modified bitumen (SMB) is susceptible to aging, which seriously influences its service performance and life. In order to strengthen the anti-aging ability of SMB, triethoxyvinylsilane was designed to organically modify layered double hydroxides (LDHs) and was applied to modify SMB. The dispersibility and storage stability of LDHs in SMB...

Power Hardware-in-the-Loop Demonstrator for Electric Vehicle Charging in Distribution Grids

A simple and low-cost Power Hardware-in-the-Loop (PHIL) demonstrator is developed for the purpose of studying the impact of Electric Vehicle (EV) charging on low voltage distribution grids. An energy saving power circulating method with potential bi-directional function is proposed in this study as well. The distribution grid under test runs on...

Study of Back-end DC/DC Converter for 3.7 kW Wireless Charging System according to SAE J2954

In a wireless charging system, a back-end DC/DC converter can be used after the coil rectification stage to match the battery charging requirements and to optimize the resonant converter operation. In this paper, a synchronous boost converter is selected according to suggested coil parameters from SAE J2954 standards on a WPT1 3.7 kW power class...

Solvent-cast 3D printing of magnesium scaffolds

Biodegradable porous magnesium (Mg) scaffolds are promising for application in the regeneration of critical-sized bone defects. Although additive manufacturing (AM) carries the promise of offering unique opportunities to fabricate porous Mg scaffolds, current attempts to apply the AM approach to fabricating Mg scaffolds have encountered some...