A method for avoiding undesired, measurement error-induced protective tripping within a protection system of an HVDC transmission system. State variables of components of the HVDC transmission system are detected by first measuring devices to obtain a first set of measured values and by further measuring devices, which are designed in redundant fashion with respect to the first measuring devices, to obtain further sets of measured values. The first and further sets of measured values are supplied to a closed-loop control unit and a protective unit. The protective unit checks the first set of measured values for the presence of a risk of protective tripping by way of internal logic, and the closed-loop control unit regulates the HVDC transmission system as a function of one of the further sets of measured values. In the event of the presence of a risk of protective tripping, the protective unit checks one of the further sets of measured values for the presence of switchover conditions and, if present, switches over to the further set of measured values and checks the further set of measured values for the presence of a risk of protective tripping.