Turbo generator and fuel cell system having the same

Abstract

Provided are a turbo generator and a fuel cell system having the same. The turbo generator includes a housing; an air inlet formed on the same axis as the axis of the housing on a first side of the housing; a rotor, a stator winding unit, impeller, and a turbine wheel mounted in the housing; and a tie-shaft installed to pass through the impeller and the turbine wheel and rotatably and integrally support the rotor.

1 . A fuel cell system comprising:
 a turbo generator including a housing, an air inlet located on a side of the housing, the air inlet coaxially aligned with a center axis of the housing, a rotor and a stator winding unit serving as a motor-generator, an impeller serving as a compressor, a turbine wheel serving as a gas turbine, and a tie-shaft for rotatably supporting the rotor, the stator winding unit, the impeller and the turbine wheel, wherein the tie-shaft is born by a first bearing disposed proximal to a first end of the tie-shaft and a second bearing disposed proximal to the impeller and distal to the first end, respectively, a thrust disc coupled to the first end of the tie-shaft, and a first and a second thrust bearings disposed with respect to a first and second side of the thrust disc, respectively;   a fuel cell to which compressed air is supplied from the compressor;   a combustor for generating high temperature and high pressure combustion gas by burning a fuel supplied from a fuel supplier and compressed air in the fuel cell;   a battery for performing one of receiving a charge by a current generated from a motor-generator and supplying a current charge to the motor-generator;   a start signal applying unit that applies a start signal for supplying a current to the motor-generator from the battery;   a switch unit for converting a current direction between the battery and the motor-generator;   a control unit for controlling the operation of converting a current direction of the switch unit; and   a sensor unit for transmitting an operation state of the turbo generator to the control unit by detecting the operation state of the turbo generator.   
     
     
         2 . The fuel cell system of  claim 1 , wherein the air entering from the air inlet contacts the stator winding unit, the first and second radial bearings, and the first and second thrust bearings directly. 
     
     
         3 . The fuel cell system of  claim 1 , wherein air compressed in the compressor is supplied to the gas turbine. 
     
     
         4 . The fuel cell system of  claim 1 , wherein the gas turbine includes an air circulation device. 
     
     
         5 . The fuel cell system of  claim 4 , wherein the air circulation device is an air jacket. 
     
     
         6 . A fuel cell system comprising:
 a turbo generator having a compressor;   a fuel cell to which compressed air is supplied from the compressor;   a combustor capable of burning a fuel supplied from a fuel supplier and compressed air in the fuel cell;   a battery;   a start signal applying unit that applies a start signal for supplying a current to a motor-generator from the battery;   a switch unit for converting a current direction between the battery and the motor-generator;   a control unit for controlling the operation of converting a current direction of the switch unit; and   a sensor unit for transmitting an operation state of the turbo generator to the control unit by detecting the operation state of the turbo generator.   
     
     
         7 . The fuel cell system of  claim 6 , wherein the battery receives a charge by a current generated from the motor-generator. 
     
     
         8 . The fuel cell system of  claim 6 , wherein the battery supplies a current charge to the motor-generator. 
     
     
         9 . The fuel cell system of  claim 6 , wherein:
 the turbo generator includes a housing; and   air entering the system from an air inlet directly contacts a stator winding unit, a first and second radial bearing, and a first and second thrust bearing located within the housing.   
     
     
         10 . The fuel cell system of  claim 6 , wherein air compressed in the compressor is supplied to a gas turbine. 
     
     
         11 . The fuel cell system of  claim 10 , wherein the gas turbine includes an air circulation device. 
     
     
         12 . The fuel cell system of  claim 11 , wherein the air circulation device is an air jacket.