Current interruption tests of HVDC circuit‐breakers: Requirements, methods and a testing case

Abstract

Development towards HVDC grids is drawing intense development of HVDC circuit‐breakers (CBs). The increasing rated voltage and capacity requires HVDC CBs with excellent performance to be installed and comprehensive tests on HVDC CBs are indispensable. This paper contributes to clarifying clearer test requirements on the current interruption test, which is the most challenging one and proposing a novel applicable test method. It is the toughest test because when an HVDC CB interrupts fault current, a high transient interruption voltage (TIV) is produced by the operation of metal oxide surge arrester (MOSA), and a large current continues flowing through MOSA simultaneously, which means considerable energy is demanded for the test. To verify an HVDC CB's current interruption ability, voltage withstand ability and energy dissipation ability in single test can be costly and even impractical in extra high voltage classes. Alternatively, a multi‐part test method is reasonable and valuable, in which the HVDC CB can be tested with large current and high voltage one after another, while the energy dissipation ability will be verified separately. At last, a proposed synthetic test circuit is validated by a simulation and a low voltage experiment, creating high equivalence between the simulation and the validation test.