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Dual active bridge (DAB) converters are extensively used due to the advantages of wide voltage regulation range and easy realization of soft switching. Besides, the concept of partial power converters (PPCs) has been widely applied to increase the converter efficiency by reducing the power actually processed by the converter. Therefore, in this article, the DAB converter and PPC are combined. And a high frequency DAB-based PPC aiming at efficiency optimization is selected out by analyzing and comparing the characteristics of several connections. Considering the wide voltage regulation range of DAB-based PPC, the extended-phase-shift-based control strategy aiming at zero-voltage switching (ZVS) range and current stress optimization is analyzed and adopted in this article. With the trend of high frequency for power converters, the non-ideal factors like output capacitors of switches need to be considered to improve the performance. The output capacitors are taken into consideration when analyzing the ZVS performance and the magnetizing inductor is utilized to expand ZVS range. To verify correctness of theoretical analysis, a prototype using GaN devices with 1 kW rated output power and 500 kHz switching frequency is built. The experimental results are consistent with the analysis.

Field-programmable photonic array-based chips will be key components in realizing high-performance THz communication in the future. However, the optical diffraction limit prohibits their integration in chip-level sizes. Although plasmonic waveguides combined with graphene are able to possess mode transmission at THz wavelengths, their operational problems such as complex device structures or high transmission losses still cannot be addressed effectively. In this paper, by relying on a mechanism of THz surface plasmon mode of graphene and an energy distribution mechanism of the refractive index difference region, a novel hybrid graphene plasmonic waveguide is proposed, whose core design part is a simple gap-slot region. This waveguide's transmission distance is one order of magnitude longer than that of the conventional waveguide while retaining the benefit high energy confinement, under appropriate parameters. Hence the proposed waveguide can be an efficient candidate component of field-programmable photonic arrays for THz communication.

In this paper, a class E type high frequency DC-DC converter is proposed. The detailed analysis and parameter optimal design method are depicted in this paper. Based on optimal parameters, the switch can operate in ZVS condition. Also, to reduce the driving losses, a multistage resonant driving circuit is adopted and analyzed in this paper, which can utilize the energy stored in the switch input capacitance. The on/off control method is adopted to regulate output voltage and the enable signal frequency is 340 kHz. From the output side, the circuit can be seen as operating at enable signal frequency with high sampling frequency. A 20 MHz prototype is built in this paper, which verifies the feasibility of high frequency converter and control method.

Development of power electronic converters tend to achieve high efficiency and at the same time high power density in many industrial applications. In recent years, with emerging third-generation semiconductor materials i.e. Silicon Carbide (SiC) and Gallium Nitride (GaN), the switching frequency of several MHz has become a widely studied frequency band, therefore traditional technology can no longer meet the demand, and many new challenges appear. This paper presents a comprehensive review of high frequency (HF) converters, the essential challenges are analyzed such as topology selection, soft-switching technologies, resonant gate drivers, magnetic components design and optimization.

Labeled data, particularly for the outlier class, are difficult to obtain. Thus, outlier detection is typically regarded as an unsupervised learning problem. However, it still has an opportunity to obtain few labeled data. For example, a human analyst can give feedback to few data when he/she examines the results of an unsupervised outlier detection method. Moreover, the widely used unsupervised method for outlier detection cannot only take the labeled data into consideration nor use them properly. In this study, we first propose a graph-based method to endow the unsupervised method with the ability to consider few labeled data. Then, we extend our semi-supervised method to active outlier detection by incorporating the query strategy that selects top-ranked outliers. Comprehensive experiments on 12 real-world datasets demonstrate that our semi-supervised outlier detection method is comparable with the best of state-of-the-art approaches, and our active outlier detection method outperforms state-of-the-art methods.

To enhance the UVC irradiation and prolong the life span of UV-lamps, parameter optimization is conducted for electronic ballasts. In this paper, the double capacitor topology is adopted and the effects of different ratios of shunt capacitors are investigated. Experiments are performed under different lamp power levels for each shunt capacitor ratio. The irradiance in each waveband emitted by the UV-lamp is measured using illuminometers and the variation trends are studied based on the excitation characteristics of mercury atoms. The effective lifetime of the UV-lamp is obtained through application tests, and it is verified to be remarkably prolonged when the double capacitor topology is adopted. Analyses and comparisons are discussed and an optimum shunt capacitor ratio is obtained, taking both increasing the UVC irradiation and prolonging the lifetime of the lamp into consideration.

In this paper, a modeling method based on MATLAB/Simulink for a temperature-dependent SiC MOSFET in the entire working region was proposed. Using a supplementary test circuit, the output characteristics of a device in the saturated region were extracted. Based on these characteristics, the model covered the output characteristics of the device in the whole working region. From the output curves, three main parameters essential for modeling were derived. Based on the Si lateral double-diffused MOSFET model, a temperature-dependent static model of SCT20N120 was established by adding a temperaturedependent compensation voltage source to simulate the temperature characteristics of the threshold voltage and a temperature-dependent compensation current source to compensate for the drain current error in the linear region due to the differences in structure and material between Si and SiC. In addition, based on the gate equivalent circuit, the dynamic model of the target device was established. The temperature-dependent static simulation results could simulate the actual measured values well. Furthermore, based on the comparison between the dynamic simulation results involving the device's turn-on and turn-off process losses and the actual transient state losses derived from a double-pulse test under the conditions of Vds = 300 V, Id = 15 A, Rg_exton = 18 Ω, and Rg_extoff = 12 Ω at 200 °C, the maximum error was 6.7%.