Feedforward control processes for variable output hydrogen generators

A process for operating a hydrogen generator comprising:

• providing raw materials at effective feed rates into the hydrogen generator, said the materials comprising fuel, an oxygen gas, and water,
• reforming the fuel in the presence of steam to produce a reformate comprising hydrogen, carbon monoxide and carbon dioxide;
• converting at least some of the carbon monoxide to carbon dioxide;
• determining conditions of the generator;
• determining conditions of the raw materials;
• selecting predetermined feed rates for the raw materials using the conditions of the generator, the conditions of the raw materials and a look up table of predetermined values;
• controlling a feed rate of each of the raw materials to substantially the predetermined feed rates;
• performing a transition rate-limiting operation;
• and
• controlling a rate of change of the feed rate of each of the raw materials in accordance with a predetermined rate commensurate with the rate of change in the transition rate-limiting operation.

A method for operating a hydrogen fuel processor with low levels of carbon monoxide comprising:

• adjusting a water to hydrocarbon fuel ratio and an air to hydrocarbon fuel ratio in accordance with a predetermined algorithm, wherein said fuel processor comprises a supply of said hydrocarbon fuel, and water and steam supplied to a reactor to produce hydrogen fuel comprising hydrogen and carbon monoxide, followed by the reduction in concentration of said carbon monoxide in said hydrogen fuel by passing said hydrogen fuel first to at least one water gas shift reactor and then to at least one preferential oxidation reactor, wherein said water is added to the hydrocarbon fuel prior to said hydrocarbon fuel entering said reactor, and wherein air is added to said at least one preferential oxidation reactor in accordance with said algorithm, wherein said algorithm comprises determining a target hydrocarbon fuel flow (B) and a current hydrocarbon fuel flow (A), then determining a present difference (D)=(B)−(A), and then comparing said difference (D) with a predetermined threshold value to determine whether said fuel processor is turning up production of hydrogen, turning down production of hydrogen or operating at a steady state mode and wherein a higher ratio of water to fuel and air to fuel is added when said fuel processor is turning up production for a preset period of time than when said fuel processor is operating at a steady state mode and wherein a lower ratio of water to fuel and air to fuel is added when said fuel processor is in a turning down of production mode.