Abstract: The transmission power of a conventional ultra high voltage direct current（UHVDC） transmission system is limited when the receiving-end commutation fails or DC blocks, which will lead to the reactive power surplus of the converter station at the sending end and induce the overvoltage of the sending-end system. An overvoltage suppression method based on the controllable self-recovery energy consumption device is proposed, which can prevent the voltage rise of the conventional UHVDC transmission system from being too high. Firstly, the mechanism of the overvoltage at the sending end is analyzed. Secondly, the overvoltage suppression principle of the controllable self-recovery energy consumption device is introduced, and the device parameter setting method is given. Finally, the effectiveness of the controllable self-recovery energy consumption device for realizing the transient overvoltage suppression of the conventional UHVDC transmission system is verified by PSCAD/EMTDC and the test platform.