NOVELTY - Fuel cell module comprises a fuel cell stack (1), a direct current-direct current (DC-DC) converter (2), and casing (11) with the fuel cell module and converter. The converter controls the electrical output of fuel cell stack. The DC-DC converter includes an electrical circuit-mounted substrate provided with the switching semiconductor. The electrical circuit-mounted substrate is arranged between the fuel cell stack and the switching semiconductor. The DC-DC converter is equipped with heat radiation apparatus.    USE - Fuel cell module is used for manufacturing power generator system for generating electric power through chemical reaction.    ADVANTAGE - The power module reduces the iron loss in the high frequency transformer. The module is capable of restraining the adverse effect based on temperature of fuel cell stack to the switching semiconductor, thus reducing loss of switching semiconductor. The module reduce losses in DC-DC converter of fuel cell module. The module has arrangement that promotes temperature rise of magnetic core, thus increasing conversion efficiency of boost converter. The module provides automatic increase and reduction of generated current of fuel cell stack based on status of the fuel cell.    DETAILED DESCRIPTION - Switching semiconductor is arranged between the electrical circuit-mounted substrate and heat radiation apparatus. The switching semiconductor is either a power MOSFET or insulated gate bipolar transistor (IGBT). The fuel cell module is a polymer electrolyte fuel cell module. The heat radiation apparatus is provided with a cooling medium. The inductor and transformer have a Ferrite magnetic core. The heat radiation apparatus is provided with a cooling medium. The DC-DC converter is equipped with a switching semiconductor, a smoothing capacitor, and an electrical circuit-mounted substrate provided with the switching semiconductor and the smoothing capacitor. The electrical circuit-mounted substrate is arranged between the fuel cell stack and the switching semiconductor. The smoothing capacitor is mounted on the same side of the electrical circuit-mounted substrate as that of the switching semiconductor. The smoothing capacitor is an electrolytic capacitor.    DESCRIPTION OF DRAWING(S) - The figure shows cross section view of fuel cell module with boost converter.    Fuel cell stack (1)    Converter (2)    Casing (11)    Gas exhaustion apparatus (80)    Fuel supply apparatus (81)    Heating medium supply apparatus (91)    Insulation unit (501)