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Where Do SiC’s Benefits
Add Up? Mitsubishi Electric weighs in on the
applications and designs in which a switch to SiC makes economic sense.
S
tandard silicon devices still dominate the power electronics market but are losing ground
By Maurizio Di Paolo Emilio
discussed the importance of SiC and the opportunities for the technology com- pared with silicon.
Combining silicon IGBTs with SiC Schottky barrier diodes can achieve efficiency improvements with rela- tively minor cost increases and can be a reasonable compromise in many applications. But the Mitsubishi engi- neers noted that the only way to increase efficiency significantly without chang- ing the topology is to use SiC. That said, SiC remains considerably more expen- sive than silicon, so it’s important to tar- get applications in which the resultant energy savings or some other technical advantage will justify the economics of a switch to silicon carbide power devices.
Mitsubishi Electric focuses on SiC for high-power devices, primarily because they are vertical devices that lend themselves to higher-power operation. “Gallium nitride is a material that we have some experience with within our RF group,” according to the company. “And we think it is certainly useful in lower-power applications. But so far, our power device development has focused on SiC, primarily because it’s better- suited for higher-power applications. So we have device modules rated up to 1,200 A, and we have voltage ratings up to 3.3 kV in commercial production.”
One of the main obstacles to SiC adop- tion is its relative newness. Engineers designing for high-power appli-
to silicon carbide alternatives as indus- tries work to meet the high-power chal- lenges of the near future. Depending on the requirements and cost tolerance of the application, SiC devices may replace silicon equivalents to maximize system efficiency or may be deployed along with silicon in hybrid solutions that trade off some efficiency for manageable cost. In an interview with Power Electronics News, Adam Falcsik, product manager; Mike Rogers, applications engineer; Eric Motto, chief engineer; and Tony Sibik, vice president of global development and marketing — all with the Power Devices department at Mitsubishi Electric —
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