Smart energy management is a key element for building a reliable power infrastructure based on volatile renewable energy sources. Like wind and solar. In smart grids, bidirectional converters are needed to link and balance power generation and storage/usage. And also to offer an intelligent way to harvest the synergies of fast-growing applications like Electromobility.
Enhanced by the global push to reach carbon reduction and at best carbon neutrality in the near future, the drive towards alternative renewable energy sources is accelerating.
Due to their scalability and low capital costs, wind and solar power generation are among the most promising concepts for meeting future power demands in a sustainable way. But how to manage a grid that is based more and more on such volatile power sources? A part of the answer is smart grid management together with advanced energy storage systems (ESS). Luckily, a second upcoming application offers a high potential to address this challenge. Electromobility as a replacement for vehicles driven by combustion engines.
Vehicle-to-grid (V2G) and vehicle-to-building (V2B) will boost grid stability
The advent of large battery capacity being spread globally has given rise to a range of forward-thinking concepts on how to integrate these power sources for power demand peak shaving. They can be leveraged as part of a solar – or wind – power strategy for homes and commercial buildings to use renewable energy sources for charging electrical vehicles (EVs), and to restore that energy during a power outage or to flatten peak demand.
For individual users, local networks are attractive as a way to become independent from grid quality and prices. Residential installations, consisting of local power sources and an energy storage system, are primarily used to supply daily power consumption. In case of a power shortage or overflow of the residential installation, the power delta can be supplied to or from the grid. EV charging offers a way to at least reduce the needed energy storage capacity of the local system. This V2B approach is stretched even further to consider power needs at a national level. Levelling out power demands in conjunction with a broader move to renewable energy using V2G.
Pushing Electromobility with fast-charging infrastructure
Many customers are reluctant, however, to buy a battery-driven vehicle. The main concerns are the limited driving range and the availability of charging stations. But also the long duration of the re-charging process itself.
In order to make charging more convenient, comparable to that of refuelling a car, charging times need to be reduced tremendously. Powerful DC EV chargers are an attractive choice for public charging. Because they charge much faster than the standard AC wallbox that many EV owners have in their home. Today, a DC charger with 150 kW can charge-up an EV with 200 km range in around 15 minutes. High-power charging piles are usually built with modular subunits of 20 – 50 kW each. This stacking approach facilitates the maintenance of the piles and improves system robustness.
Bidirectional converters enable a smart future
To further enhance V2G and V2B systems, bidirectional converter systems are necessary in infrastructure like DC EV chargers. Or energy storage systems. Only with efficient bidirectional power stages can an attractive power balance be achieved. Recently launched wide-bandgap components are well known for their benefits in converter designs. The reduced conduction losses of silicon carbide technology and the improved switching behaviour are crucial for an efficient and fast power exchange.
Infineon’s broad product portfolio offers many attractive choices for bidirectional power converter designs, from power switches, gate drivers and microcontrollers, to sensors and security solutions.
Additionally, a growing number of reference designs will support customers in reducing their own development times and efforts. A bidirectional DCDC converter is the first example: the REF-DAB11KIZSICSYS is able to provide up to 11 kW at 550 V to 800 V output voltage. It can be easily re-used to speed up the fast prototyping of new EV charger and ESS projects. In the near future, reference designs for 22 kW DC wallboxes and 50 kW subunits for high power chargers will follow.
Conclusion
To use renewable energies efficiently, smart grid management should include resources like EV batteries for better power management. This will only be feasible with bidirectional power converters in vehicles and infrastructure alike. Infineon as your one-stop partner will therefore not only support you with top-notch products from their wide portfolio, but will also be there as a trusted adviser for your system design – and to make your life easier, safer and greener.
Learn more about Infineon and bidirectional converters: www.infineon.com.