Performance of a new fast switching DC-Breaker for meshed HVDC-Grids

For the future demand of electrical energy, both a reliable and an environmental friendly solution is of high importance. The integration of many widely dispersed regenerative energy sources imposes a great challenge for the existing HVAC grids. A meshed, multiterminal HVDC-SuperGrid is considered to be the best and most efficient solution. This concept would be realized as an overlay grid alongside existing AC-grids, which enables large and controllable energy exchanges over long distances. Extremely high reliability and availability of this HVDC-Grid will become a key point in future, obviously. Fast acting, robust DC-Breakers will be necessary for this purpose, too. This paper presents a new thyristor based DC-Breaker of high switching speed and robustness. The generic requirements for HVDC-Breakers are discussed alongside with known proposed concepts. Afterwards, the characteristics and the dimensioning of the new DC-Breaker is presented and investigated in detail. Measuring results from a test setup show the capabilities and advantages of the new topology.