Abstract: A power conditioning system (PCS) includes: a grid blackout determiner, a voltage controller, and a processor electrically connected to the grid blackout determiner and the voltage controller. The processor is configured to identify a state of a grid as a blackout state or an unstable state based on at least one of an amplitude or a frequency of a voltage of the grid that is detected by the grid blackout determiner, control the voltage controller to adjust, based on the identified state of the grid being the blackout state or the unstable state, load voltage input to the voltage controller to be equal to a command voltage, and adjust, based on the identified state of the grid being the blackout state or the unstable state, a first frequency of the detected voltage of the grid to a second frequency that is different from the first frequency.

Abstract: A power conditioning system (PCS) includes: a grid blackout determiner, a voltage controller, and a processor electrically connected to the grid blackout determiner and the voltage controller. The processor is configured to identify a state of a grid as a blackout state or an unstable state based on at least one of an amplitude or a frequency of a voltage of the grid that is detected by the grid blackout determiner, control the voltage controller to adjust, based on the identified state of the grid being the blackout state or the unstable state, load voltage input to the voltage controller to be equal to a command voltage, and adjust, based on the identified state of the grid being the blackout state or the unstable state, a first frequency of the detected voltage of the grid to a second frequency that is different from the first frequency.

Abstract: A method for purifying carbon nanotubes (CNTs) includes heating the CNTs including metallic impurities and metallic oxide impurities; reducing the metallic oxide impurities by passing a reducing gas through the CNTs; removing the metallic impurities and the reduced metallic oxide impurities by passing a liquid halide through the CNTs using a carrier gas; and cooling the CNTs. Therefore, by simply passing liquid chloroform through CNTs using a carrier gas, a method for purifying CNTs can be provided so as to simply, economically, and effectively remove metallic impurities from the CNTs in a short time through one step. In addition, the purification effect can be further improved by removing the metallic oxide impurities as well as the metallic impurities through the reducing step. In addition, it is possible to improve the purification effect by further performing a step of removing a halogen or an acid-treatment purification step.

Abstract: A method for purifying carbon nanotubes (CNTs) includes heating the CNTs including metallic impurities and metallic oxide impurities; reducing the metallic oxide impurities by passing a reducing gas through the CNTs; removing the metallic impurities and the reduced metallic oxide impurities by passing a liquid halide through the CNTs using a carrier gas; and cooling the CNTs. Therefore, by simply passing liquid chloroform through CNTs using a carrier gas, a method for purifying CNTs can be provided so as to simply, economically, and effectively remove metallic impurities from the CNTs in a short time through one step. In addition, the purification effect can be further improved by removing the metallic oxide impurities as well as the metallic impurities through the reducing step. In addition, it is possible to improve the purification effect by further performing a step of removing a halogen or an acid-treatment purification step.