The thyristor is widely applied in the line-commutated-converter(LCC)HVDC. As a result

the LCC HVDC consumes a large amount of reactive power when it transmits the active power. If the block

emergency stop

power runback or continuous commutation failure occurs in the converter

it is easy to produce AC overvoltage that the reactive power compensation devices cannot be removed in time. Although the traditional control strategy based on the switching sequence table of the absolute minimum filter and minimum filter can switch off filters one by one

it may cause HVDC block in the severe fault condition because of the slow excision. In this paper

a filtering-rule-based control strategy for switching off two or more filters once is proposed

which is implemented by calculating the cutting-off numbers of different filter types. The above two control strategies are compared in the simulation. It shows that the filters can be removed fast and the AC overvoltage can be suppressed effectively for the filtering-rule-based control strategy.