High heat resistance, low inductance, and low thermal resistance are required for power module packages that bring out the performance of wide-gap semiconductors. This paper reports the results of developing a power module for wide-gap semiconductors.

　This article describes magnetic components in high-frequency-switching power converters from the viewpoint of structures. Not only permeability and magnetic flux density but also eddy current and self-resonance should be considered to design the magnetic components in high frequency. As examples, first, air-core planar inductors which can suppress the increase in resistance and the decrease in inductance due to eddy currents at high frequencies, is described. Next, toroidal transformer which can adjust leakage inductance by a wire guide produced by a 3-D printer, is explained. Third, a load test method for high-frequency transformers using two power supplies, is described. In the proposed method, the two power supplies only need to supply power losses of the transformer because the power is circulated between a primary side and a secondary side. Hence, the load test of high-frequency transformers whose capacity is larger than that of the power supply, can be performed without a high-frequency load.

　Recently, achieving carbon neutrality which means balancing CO₂ emissions and absorption is a global concern. To realize carbon neutrality, developing power electronics technologies that significantly contribute to reducing the emission of CO₂ are important issues. In addition, to smoothly develop next-generation power electronics technologies, interdisciplinary action and mutual understanding from the material, components, circuit, and system levels are important. Furthermore, magnetic components used in power converters are one of the basic and important components for improving power density and efficiency. Therefore, this paper presents the latest trend of power electronics technologies and applied technology of magnetic components for power electronics.

　This paper presents the modeling method of conducted noise on AC/DC converter using SiC devices. The common-mode equivalent circuit is derived by obtaining the impedance characteristic of the parasitic component related to the conducted noise. In addition, two or more common-mode modeling circuits are necessary to simulate two or more resonance points. The validity of the equivalent circuits and modeling method is evaluated by comparing the experiment and simulation results.

　Permanent magnet synchronous motors (PMSMs) have been applied to various fields because of their various merits such as high power and torque per size and high efficiency. This paper describes the drive system for driving the PMSM from the view of current control, position sensorless control, and other technologies, and introduces recent technological trends.

　This paper reports the e-axle systems used in electric vehicles (EV). The e-axle system consists of the electric motor, inverter, and gear. By integrating these components in a compact unit, the drive system becomes cheaper, more compact, and more efficient and directly powering the vehicle's axle. Actually, some e-axle system achieves about 20% weight re-duction by system integration in one single system housing and 30% cost reduction by eliminating component such as expensive connecting cables. The e-axle systems can be adapted to many types of vehicles. In other words, the e-axle can be fitted to the front and/or rear axles of EV. Therefore, the author surveys the target specifications and futures of the e-axle system. The main target of the e-axle system was 150 kW systems. And there are some research barriers in the electronics and/or mechanical fields.

　Wireless Power Transfer (WPT) for spacecraft can be contributed various merits, such as workload reduction, safety improvement, high heat insulation, long lifetime. Our team developed WPT prototype for space drone. WPT used mag-netic field resonance, and class E inverter (switching frequency = 6.78MHz). We performed some critical tests (electrical and EMI). As a result of the electric test, the secondary circuit was the highest, which reached thermal equilibrium at about 50 ° C (< Tj). As a result of EMI test, WPT confirmed the range of MIL-STD-461C RE02(excluding switching frequency and its harmonics).