The recovery current is an important parameter that influences the performance of the DC power supply based on the power CT in a high voltage active electronic current transformer. It is closely related to the saturation state of the core of the transformer, which harvests energy from the magnetic field generated by the current through the high voltage power line. The recovery current of three types of core material are systematically discussed in terms of their characteristics, which are the Silicon Steel, the Nanocrystalline Alloy, and the Fe-based Amorphous. The closed core of the Nanocrystalline Alloy and Fe-based Amorphous has the feature of low recovery current. Both of them can carry out a lower recovery current within 0.5A in the DC power supply; The gapped core of the Silicon Steel is able to work at the highest recovery current among the three types of cores in the same dimension, which benefits the higher input current of the DC power supply, beyond 2000A. Resultant data of analysis provides a prospective reference for design of the DC power supply with a wide range of input current by application of the combined cores.