Page 41 - Power Electronics News - December 2020
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Design Design
where the available power at the charging station As we can see, this feature acts by limiting, or
(50 kW) is equally distributed on all EVs. We also clamping, the power absorption. Actually, Power
assume each vehicle can be charged up to 43 kW Boost does something more, since it dynamically
(which is a common value). In the first use case, balances the load among the EV charger and oth-
there is only one vehicle and therefore it will er devices, such as home appliances.
receive the maximum power available, 43 kW. In
the second use case there are two vehicles and The third and last remarkable feature is Dynamic
each of them will be charged with 25 kW (half Power Sharing, or DPS, a combination of Power
the maximum power available). In the last use Sharing and Power Boost capabilities. This fea-
case, there are three vehicles, and each of them ture is very relevant for buildings, where a tight
will be charged with about 16 kW (one third the monitoring of the power demand can avoid ex-
maximum power available). ceeding the maximum capacity. When the power
demand is higher than the maximum capacity,
The second relevant feature is Power Boost, the available power is equally distributed across
also known as peak shaving. This feature avoids the points of load. If, instead, the power demand
exceeding the maximum energy capacity availa- is lower than the maximum capacity, the remain-
ble at the charging point. Of course, this is very ing available power can be fed back directly to
important for home EV chargers, since it avoids the grid.
the user to be charged of extra costs by the pro-
vider. As shown in Figure 5, Power Boost limits Figure 5: the power boost feature.
the power consumption to a user defined thresh- CONCLUSIONS that Smart Charging is an intelligent and flexible ▶ no need for heavy modifications to the exist-
old. In the picture, the red and gray plots refer to This article has provided a sufficiently detailed technology able to stabilize networks, reduce ing power network infrastructure.
a system with and without Power Boost enabled. overview on EV smart charging. We have seen costs and exploit renewable energy sources. The
most valuable benefits arising from Smart Charg- Safely balancing the energy usage between elec-
ing implementation are: tric vehicle charging stations, as well as other
power demanding devices, ensures the most
▶ dynamic and flexible adjustment of EV charg- efficient charging of EVs based on the available
ing time and speed; power capacity.
▶ increased efficiency;
For More Information
▶ GaN-based Dickson converter enhances Electric Vehicles efficiency
▶ Electric Vehicles: 48V is the new 12V
Figure 4: an example of power sharing.
40 DECEMBER 2020 | www.powerelectronicsnews.com DECEMBER 2020 | www.powerelectronicsnews.com 41
