Whenever I have a conversation about electric vehicles (EVs), I often hear the opinion that these vehicles do not have enough range to drive long distances. To a large extent that is true, even though Tesla and several other car vendors are rolling out vehicles in the +200-mile range. But there is also another impediment that reduces the attractiveness of EVs to many, and that is the dearth of charging stations. These stations need to be available everywhere – as prevalent as gas stations – before we will see a proliferation of EVs.
The number of EVs is forecasted to rise over the next five years, with significant growth of over 50 percent globally. China is expected to be the leader in this pack. One report predicts EV ownership growth from 500,000 in 2015 to 5 million in 2020. Along with this comes the rapid development of charging stations and charging piles. A charging pile is similar to a charging station where AC power is converted to DC power to charge the battery of the vehicle. However, a charging pile can just be an AC to AC conversion with more focus on diagnostics and monitoring. The ramp of these systems is being accelerated due to new government incentives.
Let’s clarify a few definitions on charging systems. A charging station is also known as an EV charging station, charging pile and charge point. It is part of an infrastructure that supplies electric energy for recharging EVs. There are three main levels when charging an electric vehicle, and all three are important to know before we plug in:
So where do charging piles come into play?
While Level III fast-charging is primarily DC, there is an AC version as well. The commonality with charging piles is that they do less power management (conversion) and more energy monitoring, diagnostics and communications – which are all necessary for commercial applications. This enables owners of a commercial place (like an office building or restaurant) who offer stations so customers can fast-charge vehicles to better optimize their energy bills and appropriately charge the vehicle owners.
Finally, it is important to note that these systems are considered industrial solutions. It is not necessary for the components needed to build EV charging stations and charging piles to be automotive-grade versions. Automotive-grade solutions require more rigorous qualifications and therefore time-consuming and expensive to build.
TI’s new subsystem reference design Vienna Rectifier-Based Three Phase Power Factor Correction Reference Design Using C2000™ MCUs for large power transfer and features TI’s C2000™ microcontroller and UCC21520 isolated gate driver and other products in the design.
Vienna rectifiers are developed for large power systems such as 60kW and above. The significance of this reference design is to showcase the value of this rectifier. High-power charging pile systems transfer power significantly faster, typically 30 to 40 minutes. This reference design has an efficiency target of 98 percent with the gate driver as a strong enabler in reducing switching losses. In addition, the C2000 MCU accelerator enables fast control loop execution and the in-built Sigma Delta Demodulators enables accurate current sensing.
Vienna Rectifier-Based Three Phase Power Factor Correction Reference Design Board
With tools and resources such as the three-phase PFC Vienna rectifier reference design, charging stations and piles can not only increase in popularity, but deliver high efficiency, quickly.
A comment on the Level 1 charging time: the 2016-2017 Volt takes about 19 hours to charge using the normal setting (8 amp), and about 13 hours if you remember to override each time you plug in the supplied charger (changing it to 12 amps). Using the supplied charger at 240V (which is 'off script') drops the time to 8.5 hours. Using a true Level 2 charger drops the charge time to a little over 4 hours (typically 4'13" at a near-constant 3730 watts, according to my recent experience).
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.