Background

High-voltage, high-current electrical systems are necessary for a number of important applications, including generating X-rays, producing electrical arcs, scientific research, and military purposes. Unfortunately, there is a substantial lack of high-voltage high-current devices available commercially.

Cascade structured devices are one example of a currently commercially available type of high-voltage, high-current device. However, the balancing network design of such devices does not provide adequate voltage scalability. Further, these devices have comparably low yield rates that drive increased costs. Thus, there is great need for an alternative way of realizing high-voltage high current devices.

Technology Overview

NC State researchers have developed a novel high-voltage cascaded supercascode semiconductor switch by connecting multiple devices in series. This invention works on the principle of sequential switching. High voltage cascaded supercascodes are formed using low-voltage Si/SiC MOSFETs in combination with a string of SiC normally-on n-channel JFET devices. Further, the device is equipped with an active balancing network consisting of clamping devices. To increase performance, multiple cascaded supercascodes are included in parallel and can share the same balancing network by adjusting the active balancing network components.

The high dv/dt made possible by this device presented a unique packaging challenge. Fortunately, the NC State researchers have further developed a novel organic laminate packaging system utilizing dielectric fluids. This both protects and cools the device, thus solving the packaging problem.

This innovation provides a promising way to solve the voltage scalability issues of high-voltage cascade switch technology, as well as to improve the dynamic performance and reduce device losses for any high-voltage switch.

Benefits

Solves the voltage scalability problem.
Allows for creation of high performance high-voltage cascade switches.

Applications

Scientific research
Military applications
Medical X-Ray machines
Ignitions switches in combustion engines, such as automotive engines.

Opportunity

NC State is looking for any partners interested in further developing and licensing this promising technology.

High Voltage Cascaded Supercascode Power Switch

Patents

IP Status