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Wide bandgap semiconductors show superior material properties enabling silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) present good features on its switching speed and withstand voltage. However, the high voltage and fast switching characteristics of SiC MOSFETs also put forward new requirements for voltage measurement, that is, high bandwidth under high voltage conditions. This article proposes a new voltage divider structure and a proactive parameter design compensation network to build high voltage and high bandwidth voltage sensing circuit. This structure utilizes the characteristics that the same resistor has the same parasitic capacitance to meet the high frequency constraints of the voltage sensing circuit. The influence of parasitic parameters and load parameters on circuit performance is analyzed in detail, which provides a basis for the compensation network design. By combining the proposed voltage sensing circuit with an appropriate proactive parameter design load effect compensation network (PDCN), the withstand voltage rating of the low-voltage and high-bandwidth voltage probes can be extended to required levels. Different from other existing methods, PDCN can actively design the compensation circuit parameters and provide the optimal parameters of the compensation circuit. This lead to a smaller input capacitance than the state of the art commercial voltage probes, which will help to obtain better performance when measuring high-speed switching voltage. The performance of the voltage measurement is experimentally verified and compared by SiC-based double pulse test (DPT) circuits. [ABSTRACT FROM AUTHOR]

Current sense resistor (CSR) is widely used due to cost and integration considerations in industrial applications. However, when CSRs are used to sense transient currents caused by power device switching, especially fast-switching silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (mosfets) with high di/dt, even a tiny parasitic inductance in CSRs bring a significant impact on its sensing performance. This article proposes a low-cost well-performance and easy-to-design current sensing circuit that uses the CSRs and an LR compensation network (LRCN) to compensate for the effect of parasitic inductance on transient current sensing. In order to support the parameter selection of the LR network, the effects of parameters such as parasitic capacitance, parasitic inductance, and loads on the performance of the proposed current sensing circuit are analyzed in detail. Meanwhile, a parasitic inductance measurement method that only needs passive probes is proposed to measure and calculate the parasitic inductance of CSRs. This circuit can not only sense the transient current on the printed circuit board level but also observe the transient current on the oscilloscope through a coaxial cable connection. Finally, experimental studies under an inductive load double pulse test setup with SiC mosfets are carried out to verify the validity and feasibility of the proposed transient current sensing circuit. Only a high self-resonant frequency inductor and a surface mounted device resistor are needed to form the LR network to fully compensate the effect of parasitic inductance on CSRs. [ABSTRACT FROM AUTHOR]