Control of fuel cell stack electrical operating conditions

A fuel cell system comprising:

• a) a plurality of fuel cell stacks;
• and
• b) an electronic controller for controlling electric input to said electronic controller from said plurality of fuel cell stacks,
• wherein pairs of said stacks are electrically connected in series, and
• wherein said electric input from said stack pairs is controlled by said electronic controller independently of the electric inputs from other stack pairs in said plurality of fuel cell stacks.

A method for controlling the electrical operating conditions of a plurality of fuel cell stacks in a multi-stack fuel cell system supplied with anode fuel and cathode air, comprising the steps of:

• a) connecting said fuel cell stacks for flow of anode fuel and cathode air therethrough in a mode selected from the group consisting of series, parallel, and combinations thereof;
• b) connecting each of said fuel cell stacks to an electronic controller for regulating an input electrical parameter;
• and
• c) adjusting said selected electrical parameter at said electronic controller in accordance with a target value.

A method for controlling the electrical operating conditions of a plurality of fuel cell stacks in a multi-stack fuel cell system supplied with anode fuel and cathode air, comprising the steps of:

• a) connecting said fuel cell stacks for flow of anode fuel and cathode air therethrough in a mode selected from the group consisting of series, parallel, and combinations thereof;
• b) connecting each of said fuel cell stacks to an electronic controller for regulating an input electrical parameter;
• and
• c) adjusting said selected electrical parameter at said electronic controller in accordance with an optimal operating point.