Abstract:
An operating method is provided for a cryo-compressed tank for supplying cryogenic hydrogen to a consumer of a motor vehicle under supercritical pressure at 13 bar or more. In order to compensate for pressure loss resulting from hydrogen removal, the removed hydrogen that has been heated in a heat exchanger is conveyed to a heat exchanger, provided in the cryo-compressed tank, by way of a tank pressure regulating valve and a branch line, which branches off of a supply line leading to the consumer. After flowing through the heat exchanger, it is introduced into the supply line downstream of the branching off of the branch line. Over a period of time that significantly exceeds the cycle times of a conventional frequency valve, either the removed amount of hydrogen is guided without limitation into the heat exchanger, provided in the cryo-compressed tank, the tank pressure regulating valve being completely open, or no return of the heated hydrogen into the heat exchanger occurs at all. Downstream of the branching off of the branch line, the supply line has a pressure regulating unit, which ensures that irrespective of the changes in the pressure in the supply line caused upstream of the pressure regulating unit by switching the tank pressure regulating valve, a sufficient and continuous supply of hydrogen to the consumer at the pressure required is guaranteed.
Abstract:
In a method for filling a cryo-compressed tank of a motor vehicle with a cryogenic storage medium, such as hydrogen, which can be stored in the tank under absolute pressure values in an order of magnitude of 150 bar or more, the hydrogen is taken in the liquid state at a suitable saturation temperature under essentially ambient pressure from a large supply vessel. Following removal from the large supply vessel, the hydrogen is compressed essentially adiabatically with a cryo pump and then is introduced at super critical pressure (13 bar or more) into the cryo-compressed tank. Preferably beforehand it is also re-cooled to approximately 20 K passing it through a heat exchanger, disposed in the hydrogen, stored in the large supply vessel. Before filling with new storage medium, the residual storage medium, contained in the cryo-compressed tank, can be removed from the cryo-compressed tank and introduced into the large supply vessel.