The European Union has set a long-term goal to go climate neutral by 2050. With this target in mind, what new technologies and solutions will drive Europe to the finish line? The electrification of everything with electric vehicles (EVs) leading the charge will play a critical role in reducing carbon emissions towards decarbonisation. The growth of the EV market in Europe continues to trend upwards accounting for almost 18 percent or about 1.7M of newly registered passenger cars in 2021.
Common barriers from even greater adoption of EVs are access to charging stations and the time it takes to charge the battery. As more EV charging stations sprout up and the grid infrastructure is built out, silicon carbide (SiC) technology can be part of the solution.
Advantages of SiC
Silicon carbide is an alternative semiconductor to silicon and is typically used in high-power applications because of its unique properties. SiC technology increases efficiency and power density of power converters used in distributed energy resources (DERs). There are also inherent benefits of using SiC in high-power applications because it can handle greater than ten times the voltage capability of silicon, enabling a thinner chip that produces lower conduction and switching losses, as well as higher switching frequency and higher temperature operation. These benefits can provide smaller, more efficient solutions for high-voltage, high-power applications at a lower system cost.
Omnidirectional Power
Europe is in a unique position as it develops its grid infrastructure to meet the growing demand. According to a recent McKinsey & Company report, “grid updates required by the electricity demands of new EV infrastructure would account for only 11 percent of total annual EU-27 grid investments; most investments will be directed at distribution systems, carrying medium- and low-voltage electricity from substations to end users, not at centralized, high-voltage transmission systems.”
To fully leverage energy input and output there are battery management solutions to explore, for example, bi-directional charging is when an EV battery supplies energy to cool a home or power a washing machine or even transfer back to the grid. We should look beyond bi-directional charging and towards an omnidirectional power flow. With an omnidirectional solution, a grid could get power from anywhere to anyone at any time, efficiently porting energy surplus into energy storage systems.
To accelerate the transition to omnidirectional power flow, deploying power electronics at the substation level can reap benefits of easing the integration of Distributed Energy Sources (DERs), optimizing our energy utilisation, enhancing power conversion efficiency and facilitating the evolution of the grid.
Renewable Energy Sources
DERs are instrumental in supporting the charging infrastructure during peak energy demands. With a forecasted 130M electric vehicles by 2035 concerns with charging during peak evening hours could be alleviated by the availability of electricity through renewable energy sources, like wind and solar power, and energy storage systems.
Since wind power fluctuates throughout the day and solar power is limited to daytime hours, they cannot be relied on as on-demand energy sources. Instead, renewable energy is stored immediately upon harvesting. This is crucial in supporting a robust charging infrastructure. The use of DERs in the electrical distribution system enables a more efficient usage of the existing high-voltage transmission system without impacting its power quality.
The process of converting electrical energy, whether it's alternating current (AC) from wind turbines or direct current (DC) from solar panels, to match that used on the electrical distribution system requires the use of power converters. Recent developments of power semiconductor technology, like Microchip’s power factor correction (PFC) converters, have accelerated the deployment of power converters with high efficiency and high-power density. The high efficiency minimises the wasted energy in the power conversion process. More energy is made available for consumption, further minimising the load on the grid. High power density enables smaller, lighter systems. With a target goal of 10,000 charging station installations per week by 2030 a more compact system reduces both installation time and the overall cost per unit.
Energy storage systems serve as an energy reservoir capable of supplying energy on demand. The efficiency of power converters in these systems is especially important as energy is lost twice, while storing energy and supplying energy.
EVs and On-board Chargers
SiC technology not only enables high performance power converter solutions for optimising grid utilisation, but also plays an important role in electric vehicles. Primarily designed in electric traction drive systems, SiC uses less energy than other semiconductor technologies, which results in longer driving range, smaller battery size and a lower system cost. Beyond the electric drive, SiC is now the power semiconductor of choice for on-board chargers, DC-DC converters and other auxiliary functions.
Omnidirectional power flow between the existing grid and DERs is further enhanced by EV on-board chargers with bidirectional functionality. When considered at a mass scale, this becomes a key component in the concept of omnidirectional power flow - providing power from anywhere to anyone at any time.
mSiC Technology
Immunity from severe weather or other disturbances such as geomagnetic storms is necessary to achieve a reliable and resilient electric grid. Power semiconductors like mSiC MOSFETs and diodes increase the reliability of DERs. Ruggedness and reliability are key differentiators of mSiC technology.
Recently, Microchip launched 3.3 kV mSiC MOSFETs with the industry’s lowest RDS(on) of 25 mΩ and diodes with the industry’s highest current rating of 90 amps; these devices are optimal solutions for medium-voltage DERs.
Microchip also provides solutions for lower voltage DERs, charging stations and on-board chargers with 700V, 1200V and 1700V mSiC products, dsPIC digital signal controllers for real-time control and design tools to help our clients develop faster time-to-market solutions.
Part of the Solution
As the EV market continues to trend upwards, the grid infrastructure from personal charging stations to public fast-charging parks will need to be built up quickly and efficiently to meet the demand. To scale at the rapid pace that is necessary, many stakeholders must come together to find solutions that result in the reduction of carbon emissions.
The semiconductor industry has a vital role in creating a more sustainable world by developing innovative sustainability solutions, such as mSiC technology, that enable EV fast charging and are a catalyst for omnidirectional power.
Author details: Clayton Pillion, VP of Microchip’s silicon carbide business unit
