Prepping for their future wave of EV vehicles, Porsche recently put the first of their 350-kW DC-CS combination chargers into use last month. With the vision of dotting the European landscape—and presumably the American landscape, too—with thousands of stations using their rapid-charge technology, they filed an application to the U.S. Patent and Trademark Office earlier last year which might prove seminal. After inspecting the application, it seems Porsche's en-route to creating a charging system that's reliable, efficient, and conducive to building a larger network.
Patent # describes "a method for supplying a number of electric charging stations with electricity, wherein AC voltage provided by an electricity source is transformed into a prescribed AC voltage level by at least one transformer via at least one star winding and at least one delta winding and subsequently routed via AC voltage lines to the number of electric charging stations."
As described in the patent, the charge station will use "at least one transformer to comprise at least one delta winding and at least one star winding that are energized uniformly." This entails "a number of phase-offset phases is increased and a power factor of respective charging stations from the number of electric charging stations is increased." Since the Mission E is reported to be capable of recharging its ~95 kWh battery in about 15 minutes, Porsche's anticipatory approach should be helpful, if not necessary, for building a dependable charging base and selling a healthy number of EVs.
According to the application, the new technology should also prove resilient. "Gradual or temporally successive buildup of power in different charging stations allows voltage spikes and corresponding wear and tear to be reduced."
Additionally, the power available can be transferred easily between stations depending on the demand: "For the gradual switching of respective transformers, the transformers can be connected or disconnected by a circuit. Accordingly, a charging station arrangement operated by means of the presented method can, even after startup, be simply and quickly extended by virtue of parallel arrangement of further transformers and charging stations." This should provide "a very large current and/or a very high voltage to be provided quickly and simply when required."
As BMW, Audi, Ford, and other major marques are interested in strengthening the current EV infrastructure, this very patent may be the catalyst needed to make the EV a viable consumer product for more than just the affluent. And, being sensible as always, Porsche understands the demands of their performance-oriented clientele—which should hopefully make the Mission E as capable of backroad romps as well as trips to the office.