High-Power-Density DC–DC Converter Using a Fixed-Type Wireless Power Transmission Transformer with Ceramic Insulation Layer

Abstract

In this study, we propose the use of a short-distance and fixed-type wireless power transmission transformer via a half-bridge LLC resonant converter. A ceramic insulating layer was used instead of an air gap, meaning that the heat generated from the transformer core and the PCB winding was quickly transferred to the external metal case, with the ceramic insulating layer acting as a heat pipe. In order to stabilize the output voltage, we proposed the use of IR photo tunnel technology, and it was applied to two ceramic insulating layers so that the voltage error signal of the secondary output voltage could be transmitted as light to the primary side. As a result, it was possible to physically separate the primary and secondary sides of the power circuit centering on the ceramic insulating layer. The experiment was carried out with the input voltage of 400 V, the output voltage of 54 V, the maximum output power of 1 kW, and the switching frequency of 1.3 MHz or higher. As a result, the maximum operating frequency was 1.83 MHz, and the output voltage stability to the load was 0.49% or lower. The power density of the experimental circuit was 380 or higher, and the maximum power conversion efficiency was approximately 93% or higher.

Inductive Compensation of an Open-Loop IPT Circuit: Analysis and Design

“…The far-field category refers to the transmission of a large amount of energy between two positions, e.g., sending energy by electromagnetic waves. Near-field WPT refers to the distance of transfer energy within the wavelength (λ) of the transmitter antenna [6][7][8]. This paper will focus on near-field WPT.…”

High-Efficiency Sine-Wave Current Pulses Charging Method in Wireless Power-Transfer System Applications

“…Ramezani et al [6] developed a wireless charger with a conversion 2 of 23 efficiency of 94.8%; nevertheless, this charger comprises an LCC-series compensation circuit, resulting in a complex and costly structure. Furthermore, Park et al [7] presented a wireless charger with a maximum conversion efficiency of 92.7% in the WPC/PMA mode, and Yoo et al [8] presented a half-bridge LLC resonant converter with a conversion efficiency of 93%. Corti et al [9] also proposed a wireless charger with a conversion efficiency of 90.0%, and Nama et al [10] designed a wireless charger with a conversion efficiency of 91.26%.…”