Takaaki Ibuchi

A study on modeling of dynamic characteristics of circuit component in TDR measurement based on Prony analysis

Identification and modeling of parasitic components in power electronics circuit has become a notable issue for electromagnetic compatibility (EMC) design to achieve faster and higher-frequency switching operations. This paper characterizes and models the dynamic behavior of circuit components with reflectometry measurement in a time domain. To this end, Prony analysis is applied to the TDR measurement data. The proposed method readily identifies the model order and is tolerant to measurement noise.

A study on packaging design of SiC power module using near-field magnetic scanning techniques

This report focuses the current distribution in a module identifiedwith magnetic near-field intensity for optimizing layout and packaging design of silicon carbide (SiC) power module. This measurement methodology can visualize the practical current distribution on a wiring pattern in a module and can estimate the effect of snubber capacitor in a DC-link of half-bridge to suppress the voltage overshoot and ringing oscillation.

Conducted emission characteristics of CCM boost converter with SiC schottky barrier diode

The ringing oscillation in turn-off of diode may induce electromagnetic interference (EMI) noise especially in fast switching operation. This study compares static and dynamic characteristics of a Si PiN diode and three type SiC Schottky barrier diodes, which have comparable voltage and current ratings, and focuses on the influence of diode characteristics on conducted emission of the continuous current mode (CCM) DC-DC boost converter. The dynamic characteristics of diode current in turn-off operation are evaluated by Pronys method. The spectrogram of conducted emission is measured to understand how the noise source could affect the conducted noise emission.

Loss and conducted noise characteristics for CCM PFC circuit with SiC-Schottky barrier diode

Active power-factor correction (PFC) circuits are commonly used in the first stage of single-phase AC/DC power converters to improve the power factor and low-order harmonic distortion. In continuous current mode (CCM) PFC circuits, the reverse recovery current of a PN diode is induced during its turn-off following the turnon operation of a MOSFET, which causes not only a switching loss but also a switching noise in the PFC circuit. This study investigates the loss and conducted noise characteristics of a PFC circuit by comparing the difference among silicon PiN diodes, silicon Schottky barrier diodes (SBDs), and silicon carbide SBDs.

A study on wiring pattern design for intelligent SiC power module with PEEC method

The fast switching operation of wide-bandgap power semiconductor devices deteriorates the Electromagnetic interference (EMI) noise characteristics of a power converter. The parasitic inductance in a power module is one cause of noise generator. This paper calculates parasitic inductance in a wiring pattern of module with Partial Element Equivalent Circuit (PEEC) method, and evaluates the current distribution in a module by magnetic near-field intensity measurement to discuss the suitable wiring pattern design for intelligent silicon carbide (SiC) power module.

An experimental study on conducted noise emission for PMSM drive with SiC inverter: Conducted noise reduction by snubber circuit

Silicon carbide (SiC) devices are attracting attention as next generation power device because of their high breakdown voltage, low conduction loss, and fast switching speed compared with conventional Silicon (Si) device. SiC power device is expected to be used in electric vehicle and hybrid electric vehicle. The large di/dt and dv/dt in fast switching operation interact with parasitic component in circuit wiring, and causes conducted noise. This study focuses on the switching behavior of SiC MOSFET and the conducted noise characteristics in a inverter. The effect of snubber circuit is evaluated with its combination of installation for SiC module.

Evaluation on active power of common-mode conducted disturbance

Power conversion equipment is known to generate common-mode conducted disturbance. The authors have studied about common-mode apparent power evaluation, which have magnitude and phase information of the disturbance, for clarifying the generating mechanism of the disturbance. This paper describes the importance of evaluation of active power, a part of apparent power of common-mode conducted disturbance, and the validation of the active power evaluation. Additionally, verification of the active power evaluation with using DC-DC converter as EUT has been considered. As a result, validation of evaluation result has been proved by comparing common-mode apparent power, calculated from active power and measured common-mode apparent power.

A study on copper loss minimization of air-core reactor for high frequency switching power converter

The volume and weight of a power conversion circuit depend considerably on magnetic components. Air-core reactor which can avoid core loss is suitable for power converters operating fast and high-frequency switching of the high voltage and large current. This study presents a compact model for the calculation of winding AC resistance of air-core solenoids, which includes the influence of skin and proximity effects, and verifies the adequacy of this model in the high-frequency region on the basis of the measured frequency characteristics of the impedance. This study also considers the optimal design dimensions of a single-layer solenoid to minimize copper loss for a given wire diameter and inductance value.