Authors: Anup Anurag, Sayan Acharya, Nithin Kolli and Subhashish Bhattacharya

Extended Abstract:

Extensive research in wide-bandgap material technology such as silicon carbide (SiC) has led to the development of medium voltage (MV) power semiconductor devices with blocking voltages of 3.3 kV to 15 kV. When these devices are used in various applications, they are exposed to a high peak voltage stress and a very high dv/dt (50 V/ns to 100 V/ns). These impose stringent requirements on the gate driver requiring a high isolation voltage capability along with a high dv/dt ruggedness, which makes it necessary to have an ultra-low coupling capacitance between primary and secondary sides of the isolated gate driver power supply. One of the key issues in achieving this MV isolation pertains to the necessary clearance and creepage requirements, as defined in IEC 61800-5-1 standards. For the successful operation of these gate drivers to be demonstrated in MV converter applications such as Solid-State Transformers [SST], MV grid-connected converters, and MV motor drives, substantial research to improve the gate drivers’ performance and provide a plug-and-play solution is needed. This work aims to comprehensively review and develop these gate drivers and consolidate various required design features concerning their galvanic isolation stage, based on normal and short-circuit operation of MV high power converter systems. Different device short-circuits protection schemes for these gate drivers are developed and implemented. Additional applications and functionalities of the gate drivers, including gate drivers required for series-connection of MV devices and intelligent, active gate drivers, are also provided. Based on our extensive prior research, this review paper also aims to provide design choices and guidelines for the gate drivers, accelerating the growth and deployment of MV SiC devices for field applications and commercial adoption.

Isolation barrier design
Isolation barrier design: C-core with PCB-based isolation (silicone insulation in second case)

This research work and the authors are associated with the FREEDM Systems Center [www.freedm.ncsu.edu], PowerAmerica (www.poweramericainstitute.org), Dept of ECE, NC State University. For more information on our research projects and publications, please visit :

https://research.ece.ncsu.edu/bhattacharya/

https://ece.ncsu.edu/people/sbhatta4/

This paper is published in IEEE Journal of Emerging and Selected Topics in Industrial Electronics.


Check full paper at: https://ieeexplore.ieee.org/document/9263099