IIT Delhi researchers at the Smart Grid Lab of the Department of Electrical Engineering have developed a truly modular, scalable, and environmentally friendly Electric Vehicle (EV) charging station with in-built solar photovoltaic interface capability.
The 20 kW Smart EV charging station is an outcome of the ‘Demonstration of Grid Supportive EV Charger and Charging Infrastructure at LT Level (D-EVCI)’ project funded by the Department of Science and Technology (DST), Government of India. It is a multi-functional charger of 20 kW, with the capability of charging a wide range of EVs like cars, three-wheelers and two-wheelers.
According to the Principal Investigator of the project, Prof. Sukumar Mishra, Department of Electrical Engineering, IIT Delhi, “The scalable multi-functional charger caters to the emerging EV charging needs of both today’s and tomorrow’s electric vehicles. There has been a demand from both the automobile industry and EV charger operators for ease of scalability in their charging units. The built-in Modularity of the developed charging platform allows charge operators to scale-up basis requirements with minimal expenses. We also have a solar interface, which works in tandem with the electrical grid for energy sharing.
One of the prominent features, which is incorporated in the IIT Delhi developed EV charger is the solar interface capability. Solar photovoltaic panels can now be used, which can assist the charger. In future, the solar panels’ capacity can be increased and finally a totally green EV charger can be built that can act as an independent infrastructure not taking any power from the conventional grid. The charging current can also be modulated based on the grid frequency, which allows a more stable operation leading to a reduction in grid failure.
The charger operators can purchase a 2 kW charger and scale-up depending on their financial capability and demand, as and when required. Currently, in India, the EV charger operators can only choose from a set of pre-fabricated charging options and incur significant unnecessary costs if they want to scale-up their charging output as the entire set-up needs to be revamped in order to cater to higher power vehicles.
The charging power in the IIT Delhi charger can be increased in increments of 2 kW, starting at 2 kW up to a maximum of 20 kW. Besides offering ease of scalability through a modular approach, the platform also has a slim design with low maintenance requirements and a user-friendly interface.
This charger’s output current can be controlled remotely based on the grid load. This controlled loading mitigates the damage to infrastructure like the distribution transformers, power cables and even total power-blackouts. The controllability is especially useful during peak load times like afternoons in summers when everyone is using high power rated A/Cs at their homes.
Where-in each module is of 2 kW capacity, helps improve the reliability of the charger as even if one of the modules fails, other modules step in and deliver uninterrupted power supply to the vehicles. As a result, although the charging time may increase minimally, it will not shut down and go to a state of zero charging. Hence, it is a controllable charging infrastructure that has been made with the help of the DST, IIT Delhi and Silov Solutions (P) Limited.
A user interface in the platform allows the charger operator to control the current going into the EV. Similarly, there are certain parameters, which capture the feedback coming from the battery management system of the EV.