In this study, a novel high step-up DC-DC converter was successfully integrated using coupled inductor and switched capacitor techniques. High step-up DC-DC gain was achieved using a coupled inductor when capacitors charged and discharged energy, respectively. In addition, energy was recovered from the leakage inductance of the coupled inductor by using a passive clamp circuit. Therefore, the voltage stress of the main power switch was almost reduced to 1/7 V_o (output voltage). Moreover, the coupled inductor alleviated the reverse-recovery problem of the diode. The proposed circuit efficiency can be further improved and high voltage gain can be achieved. The operation principle and steady-state analysis of the proposed converter were discussed. Finally, a hardware prototype circuit with input voltage of 24 V, output voltage of up to 400 V, and maximum power of 150 W was constructed in a laboratory; the maximum efficiency was almost 96.2%.

This article proposes a systematic method to construct three-port converters (TPCs) and bidirectional three-port converters (BTPCs) by integrating two dc–dc converters including nonisolated and isolated types. By adding extra one power switch and one diode, the TPCs can be constructed by the dc–dc converters. A series of the proposed TPCs can provide independent power flow control of single-input to single-output, single-input to dual-output, and dual-input to single-output. By adding extra two power switches, the BTPCs can be constructed by the dc–dc converters. The power flows between any two ports can be controlled bidirectionally without significantly altering their architecture. Finally, a typical nonisolated BTPC is analyzed and implemented with rated power of 300 W and three ports voltages of 48, 72, and 200 V to verify the feasibility and effectiveness of the theoretical analyses. The highest measured efficiency is 98.4%.

This work presents a new simple passive 3D stylus and its associated stroke reconstruction algorithm for capacitive touch panels that detects the x,y -directional position and z -directional strength without the help of a pressure sensor. The proposed algorithm can successfully detect touch information while eliminating noise. Moreover, unintended touch will be recognized and its effects are eliminated while the desired signal will be accessed by the touch system to enhance the handwriting experience. The results of experiments on a touch panel system were analyzed, demonstrating the effectiveness of the proposed stylus and its stroke reconstruction algorithm.

The bidirectional DC-DC converters are widely used in the energy storage system (ESS) and DC distribution system. The power capacity is limited when the converter is operated with smooth power transfer. In addition, the directions of the inductor current and the capacitor voltage cannot change instantaneously. In this study, a rapid energy conversion technique for smoothing and accelerating the energy transfer under the same specification of the main components in steady state is proposed. Moreover, a bidirectional DC-DC converter with a high conversion ratio is proposed to overcome the commonly low voltage input from renewable energy sources. The operating principles of the proposed converter’s step-down and step-up modes are discussed in this study. Furthermore, to achieve rapid energy conversion, digital control is a crucial component in the converter system. A digital signal processor is used as the control platform, and a control strategy is formulated to achieve rapid energy conversion. The bidirectional DC-DC prototype converter with a 24 V battery, a DC bus of 200 V, and an output power of 500 W is constructed to confirm the feasibility of rapid energy conversion. The proposed converter can be operated in CCM, BCM, and DCM conditions. The transfer period can be completed within one switching cycle when the proposed converter is operated in BCM or DCM. The energy is freewheeled before energy conversion when the proposed converter is operated in CCM condition. In the experiment, the minimum transfer period is 6.29 µs on the DCM stage.

Bidirectional DC–DC converters are key devices in the DC distribution system and the energy storage system (ESS). It is important to consider the safety of the elements in the converter for rapid conversion of the power direction. Damages may occur to the power-related components in the circuit if the direction of the inductor current or the capacitor voltage changes instantaneously. To make the power flow change smoothly and quickly, this research proposed a bidirectional DC–DC converter with rapid energy transition technology implemented in the circuit architecture. The rapid energy bidirectional transition technology added a resonance path based on the LC resonant circuit, allowing rapid energy conversion through the resonance path. Therefore, the energy in the energy storage element could be quickly converted without causing circuit surges. Analyses of the converter operating in the step-up mode, the step-down mode, and the transition operation mode are presented. The proposed circuit architecture had a high voltage-conversion ratio and a simple architecture. A prototype bidirectional DC–DC converter with a full load of 500 W, a low side voltage of 24 V, and a high side voltage of 200 V was developed to prove the concept. The feasibility of the rapid energy bidirectional transition technology was verified by the simulation results and experimental results using the prototype converter. The maximum efficiencies in the step-up mode and the step-down mode were 95.3% and 93.8% respectively. Under full-load conditions, the transient time of the energy transition from the step-up mode to the step-down mode was 17.7 μs, and the transient time of the energy transition from the step-down mode to the step-up mode was 19.3 μs.