Design and validation of an interleaved buck converter for maintenance of DC charging stations for EV

In the last years the rapid growth of Electric Vehicles led to a great expansion of the charging infrastructure. With a large number of chargers faults may occur and for this reason it is important to guarantee a good technical service, which is also needed for ordinary maintenance. The market actually offer a poor choice of devices specifically designed for on-site service of EV chargers, which are usually designed to test a fixed operating point; however, a good test device, should be able to test a charger for its entire voltage and current range. This has also to be done to check the correct calibration of the energy meters, which are responsible for the price of the charging session. A properly designed DC-DC converter can be used as power interface between the charger and a fixed power resistor; in this way it works as a load emulator and, in combination with a device that simulates the communication with a car, it is possible to test a charger at different working points. Alpitronic, which is a producer of DC charging stations, decided to develop its own test system, composed by three different elements: the HTS-MT, which is a device that emulates the communication with an EV, the HTS-DCDC, which is a DC-DC converter, and a high power external load. The goal of this thesis is the design and validation of the HTS-DCDC, a transportable 100kW Interleaved Buck Converter that together with the HTS-MT and an appropriate external load will be used by technicians during on-site service to test the functionality of the charger at every working point and check the correct calibration of the energy meters.