Energy efficiency is of great concern to any modern industrial and power system. Kept to a maximum, it serves to lower the amount of energy and cost lost, enhances the quality and constancy of the power supplied, and enlarges the manufacturers’ scope for growth and adaptation. In the case of industrial power equipment the right materials and components, SiC devices, go a long way in attaining state of the art power efficiency.
Why the choice of component selection is important
Most of the energy lost in an electric system is due to the heating of conductors and incidental losses through switching. Physically large and a nuisance to mount such silicon devices, if they don’t get rid of heat some other way, or lose a lot of heat in other systems, become much less efficient. The upgrade of switching component to one of better materials and better construction makes for a very considerable improvement in the behaviour of the whole system.
What this all comes down to is…
Material Properties – is the conductor low resistive losses & high thermal conductivitySwitching Speed – are semiconductor switches as fast as practicable, particularly in inverters, converters and motor applicationsWhere the conductor elects to get rid of the heat, are there designed paths for it to take?Is the substrate thermally conductive enough, is it using a heatsink?Dust ageing and general poor life means it will not be at full rated performance at any customer specified time in the future.SiC components saving energy on switching operations
Specifically SiC based devices: SiC MOSFETs, diodes, and power modules are gaining traction in energy sensitive applications large and small, because of:
Alloy Efficiency: Having a smaller gate charge, QG, than silicon MOSFETs means low driving losses, contributing to low conduction losses thanks to RDSON on-resistance and ensuing minimised conduction losses. In addition, with a low output gate charge, QOSS, switchers are being turned off very quickly to reduce losses.
Higher Temperatures: Designers are able to ‘allow’ SiC to run at high junction temperatures that may help with cooling design and reduce the requirements for complicated cooling systems.
Smaller Components: Smaller components mean lower weight and size systems packing more into smaller packages; energy savings on the upside – a big win in applications like EV inverters and photovoltaic inverters (PV inverters) on solar farms.
Greater Reliability: As though we needed further encouragement to adopt SiC, the 4H-SiC crystal structure stands up well to hot, high-voltage conditions, meaning that “stale” conditions and dead time in systems is less likely.Electric Vehicles (EVs). In EVs, the savings in loss power used to control the drive motor by using a SiC inverter instead of a silicon alternative permits system manufacturers serving the automotive market (and by default supplying safety critical REL (relevant electronics) thermal management products) to enjoy longer range and greater battery life.Renewable Energy. The perfect photovoltaic inverter is the one that doesn’t lose any of the energy captured from the solar PV array to the grid. While the classic inverter can’t do this, adding a soupcon of SiC greatly improves the “high way” efficiency.
Industrial Power Systems. The goal of applying high voltage SiC components as diodes and as both standard MOSFETs in a common chip improves efficiency in both industrial motor drives, and Uninterruptible Power Supplies (UPS) and industrial converters.
Supports components for energy efficiency
In terms of energize efficiency, it’s not just semiconductors that count, the prime choice of supporting electrical components can make the difference on an efficient system.
Fuses and Circuit Breakers. Protectives are a core to being high quality and in right qualified limits, steering clear of unnecessary and wastage losses from shutting down faults/cautions and the operation itself going down.
Thermal Management Materials. Substrates, heatsinks and thermal interface materials of high conductivity help keep devices cooler even at high temperature, aided by hoping a spongy layer of upper air and spreading a stream of heat as an incompressible gas. Total energy gain all cascaded.
Capacitors and Inductors. Low loss passive don’t make the ripple and switching losses that converters and inverters make.
What do you know? For Further Reading
Silicon Carbide: A Unique BMOS Technology
Frequently Asked Questions
Can SiC components replace all silicon based devices?
Not, because SiC is only right for high-voltage, high-frequency and high-temperature applications. Hybrid approaches are standard where silicon and SiC are mixed as cost and planned design dictate.
How much improvement can I expect?
It varies by application but a rough number is 10–20% loss reduction in using SiC in qualified components than suited silicon.
Are SiC components more reliable?
Yes as mentioned, SiC devices are generally more failure set aside as they are thermally and insulated to be at a higher temperature and voltage to work with separation of energy performance over the life of a device overall.