By Patrick Le Fevre, Chief Marketing and Communication Officer, Power Box
As is the case in many industries, power electronics has been affected by the Covid-19 pandemic, although we have seen a boost in new technologies and opportunities for power designers to capitalize on the benefits of E-learning.
It’s always difficult to derive trends from large industries but as the largest power electronics convention, the Applied Power Electronics Conference (APEC) took place in Houston U.S.A., as a power engineer it is interesting to take a minute to ponder and consider what will contribute to making power supplies more efficient, more reliable and exciting to design.
Overall trends and technology
For sure the so-called ‘electrification’ and transition from fossil fuels to renewable energy is a major trend that we are all aware of. This segment will require a lot of technological innovations to reach the carbon neutral level expected by the European Commission, US DOE and similar initiatives in Asia.
If we refocus on what most of the power supplies companies are developing, I foresee that four trends and one technology development will influence the power industry in 2022: Reducing energy consumption ; Power supplies becoming part of the Machine-to-Machine eco-system ; Enhanced energy storage solutions ; Acceleration of harvesting energy solutions, and all of them will benefit from the implementation of Wide Band Gap Semiconductors.
In the quest for reduced energy consumption, from harvesting energy to the grid, the power electronics industry is permanently seeking new ways to improve efficiency. International and local regulations have forced power supply manufacturers to innovate but we are seeing more stringent regulations under discussion that might require the power industry to explore new topologies, components and materials.
I would like to illustrate that trend with one example that will include and benefit from them, E-commerce.
E-commerce was already growing before Covid-19, but as consequence of curfews, working at home, and the drastic reduction of physical interaction, it has grown exponentially, putting a high demand on shipping hubs, computerized storage and the overall supply chain. Before we even mention the associated datacenters required to manage the E-commerce process, shipping hubs and warehouses have become gigantic and consume lots of energy.
Making handling and shipping hubs more energy efficient has been on the agenda for all the major players, though the 2020-2021 peak on demand was a strong a signal for them to reconsider the way to use and manage energy.
Power supplies as such are not consuming most of the energy, but when considering their strategic position in the operational chain they become a key-point in the overall process to optimize how energy is used in the complete chain. In 2022 we will see very advanced power supplies used in E-commerce handling and shipping hubs. They will not only integrate higher levels of communication, but are able to store and restore energy from supercapacitors banks, reducing peak disturbances on the grid and consumption. Already experimented with in 2021, the power supplies have been integrated into a complete eco-system with Machine-to-Machine communication. (Figure 01).
They not only deliver power to a load e.g. conveyor motors, but they are able to sense and adjust the level of energy to store in local supercapacitors bank (Figure 02).
Almost invisible, from the RFID inserted in the shipping box that will get power from RF signals, to sensors placed on motors or moving elements powered by vibration, micro-systems powered by harvested energy are developing very fast. Here also, the nanotechnology such as nanotubes make it possible to develop very small supercapacitors storing enough energy to power sensors and transmitters.
To make that possible the implementation of digital power and communication is a must, but the level of performance will require power electronics engineers to design new power solutions with the so called ‘Wide band gap’ semiconductors. Depending on the application and voltage they will select GaN or SiC types but the benefits of WBG will contribute to making E-commerce more energy efficient and to a lowering of the CO2 footprint.
Critical building blocks!
For decades, improvements in energy efficiency levels of power supplies have been made possible by technological evolutions. Moving from linear to switching technology was probably the major one, followed by a number of more minor leap-frogs until digital power came to market.
Despite it having been on the market for several years, with the emerging WBG technology and the possibilities offered by those components, digital control becomes an absolute MUST and I strongly believe that will be a major building block for power designers when developing new products.
Component wise, the WBG transistors are without doubt the ones that will prevail in 2022. That said, conventional Power FETs are also making big progress and power designers will have to achieve new levels of business assessment and acumen when selecting the most appropriate technology for their applications.
The third building block I foresee as important is the advanced planar transformer with interleaved multicore technology. Not all power supplies require megahertz switching but considering the constant quest for smaller power supplies with higher efficiency, power designers will have to consider new types of transformers and new winding techniques. In that respect they will be helped by ferrite manufacturers developing new materials but also by Artificial Intelligence software shortening time to design and test new transformer types (e.g., Frenetic, Simba).
One specific example of that is research we are currently conducting at PRBX, combining digital control, GaN, and multicore transformers with advanced wiring and auto-tuned performance within the wide operational range that we see in some industrial applications that require extremely wide input voltage ranges, as well as outputs subject to repetitive peak loads. Final products is not ready yet but it will not be possible without the combination of digital control, WBG and advanced magnetics (Figure 03).
I believe many of the new products that we will see in 2022 and onwards will be based on those three building blocks, which I’m sure will also include more communication to become part of a Machine-toMachine ecosystem.
In WBG we trust!
What is interesting with the Wide Band Gap semiconductors is that we see a similar situation to when the first power MOSFETs were launched. Some immediately considered the benefits of the WBG, and that despite early products not being very user friendly due to them being based on a depletion mode that requires very specific drivers, it didn’t take too long for power semiconductors manufacturers to provide ‘easy-to-use’ solutions.
It is now more than five years since manufacturers were promoting the benefits of that technology but if the Go To Market is ready, the Go To Application for mass users is requiring a certain amount of time. We are all familiar with the ‘camel-back’ curve reflecting new technology adoption and crossing the chasm.
Experienced power designers have crossed that technological chasm many times, with the latest one being the migration from analog control to digital, and it taking more than 10 years to reach a significant level of adoption (Figure 04).
In the case of WBG – and especially Gallium Nitride (GaN) – early adopters entered the fray much quicker than some predicted a few years ago. It is no surprise that the PC and Mobile/Nomad industries were some of the early adopters. The number of USB-C chargers using GaN semiconductors announced in 2020-2021 is very impressive. Particularly worthy of mention is Navitas’ next-generation GaNFast power IC that will drive the 120W ultra-fast charger supplied ‘in-box’ with vivo’s iQOO-brand flagship iQOO 9 Pro mobile phone, demonstrating the rapid adoption of GaN by the ‘nomad’ industry. But not just its electrical performance, using GaN reduces the physical size by 26%, reaching a stunning 1.3W/cc power density, which is quite incredible (Figure 05).
If it took 10 years for digital power to become a de facto technology, it took only five years for WBG to reach a similar level. What is interesting in the development of the WBG semiconductors is that due to the specificity of this technology, that’s very low internal resistance and ability to switch very fast, the packaging is very important and we see a lot of innovation from manufacturers to offer optimized solutions. Technology wise the Efficient Power Conversion (EPC) approach is very interesting, minimizing interconnection losses, and making it possible to shrink a power converter to an unprecedented size (Figure 06).
Something to mention is the amazing number of technical webinars proposed during the Covid-19 era, not to mention the virtual APEC-2021. Many companies have taken that as an opportunity for their power designers to attend online training, and as a result some power-semiconductor companies have reported shipping up to 10 times more evaluation kits than before the pandemic days.
If we simplify the market into two segments: High voltage (using SiC) and Low voltage (using GaN), we see two different patterns. High voltage applications e.g. electric vehicles and solar are familiar with SiC transistors, and for that segment it is no big revolution for power engineers to undergo a learning phase for the relatively new low voltage technology.
Conclusion
In many different ways we have all been affected by the pandemic, although looking back it has contributed to boost new technology learning and to speed innovation. Considering all of that, 2022 will be a very important year for WBG and we can expect many new power supplies (AC/DC and DC/DC) to be announced during the year. 2022 will be a very exciting year for all us designing power solutions
