Toyota Industries Corp developed a system that controls charging time, etc for multiple plug-in hybrid vehicles (PHEVs) and electric vehicles (EVs).
The company announced the development of the system Jan 30, 2012. It tests the system from January to March 2012 by using 21 charging stands developed by the company at seven sites in Toyota City, Aichi Prefecture, Japan.
When multiple PHEVs/EVs are charged at the same time in a certain area, it is possible that power consumption exceeds the capacity of charging facilities or the amount of electricity limited by a contract with a power company.
In the case of 200V normal charging, about 3kW of electricity is needed to charge a vehicle. Therefore, if four vehicles are charged at the same time at a charging station whose limit is 10kW, power consumption will exceed the limit.
To prevent such a case, the newly-developed system controls the amount of electricity supplied by each charging stand by reducing electricity supply for some vehicles, charging vehicles at different timings, etc so that power consumption does not exceed the limit.
Also, data on the status of each charging stand is sent to a data center. And, based on the data, values that reduce the peak amount of electricity used in a certain area are sent to charging stands.