MULTIVARIABLE OPERATION AND CONTROL OF FUEL CELL

摘要

PURPOSE:To enable electric energy to be efficiently produced by maximizing total thermal efficiency which is the product of fuel utilization efficiency, current efficiency and voltage efficiency through multivariable control. CONSTITUTION:The relationship between load current and total thermal efficiency is obtained from both the relationship between the load current of a fuel cell 1 and its voltage and the relationship between the load current and fuel utilization efficiency by using the temperature of the fuel cell 1 as a variable. These data are used as the inputs to a control device 9 so as to control the temperature of the fuel cell 1 so that its thermal efficiency beomes maximum for each load current. The temperature of the fuel cell 1 is detected by a temperature sensing element 8. When a fuel contained in anolyte is consumed, the consumption is detected by a concentration sensor 7 and then a fuel supply valve 10 is opened by the control device 9 to supply the fuel from a fuel tank 11 into an anolyte tank 2.