Commissioning of a novel high power medium voltage DC laboratory with exemplary studies on an MVDC hybrid contactor

DC Grids become more relevant in diverse application areas. In addition, the increasing operating voltage leads to a lack of suitable laboratories to investigate future components. Therefore, a new test facility is built and presented in this paper. Two air insulated three phase transformers with several terminal connectors allow a flexible voltage adjustment. A connected 12 pulse thyristor-controlled rectifier provides a voltage up to 12 kV or a current up to 30 kA. The maximum output power is limited 18 MW due to mains supply restrictions. A sophisticated control and safety system allow tests to be conducted for almost any type of load investigation on a wide range of breaking equipment. The complete circuit configuration is explained and some initial tests on a new medium voltage hybrid circuit breaker are presented. This switch is designed to operate at a supply voltage of 3 kV, so fast switching is critical. The results are investigated and necessary design improvements are derived. The laboratory and the newly constructed switch are the basis for new research fields in hybrid and DC switches in general.