Electric drive system for vehicle, electric control system for vehicle, electric drive method for vehicle

Abstract

In an electric drive system for a vehicle, an alternator is driven by an engine to generate electric power which is used to drive a motor to generate a driving force. During a retardation of the vehicle, the motor is operated as an alternator to convert kinetic energy to electric energy which is used to retard the vehicle. A retard resistor is provided for absorbing electric energy generated during the retardation state. The retard resistor is cooled down by an AC blower.

1 . An electric drive system for a vehicle, comprising: 
 an alternator driven by power of an engine of said vehicle to generate electric power;    a rectifier for rectifying the electric power outputted by said alternator;    a converter for converting an output of said rectifier to an alternating current;    a motor driven by an output of said converter and rotated by wheels of said vehicle mechanically coupled to said motor to generate electric power;    a resistor for converting the electric power generated by said motor to thermal energy; and    a blower for cooling said resistor.    
   
   
       2 . An electric drive system for a vehicle according to  claim 1 , further comprising a second alternator driven by the power of said engine to generate electric power, wherein said blower is driven by electric power generated by said second alternator.  
   
   
       3 . An electric drive system for a vehicle according to  claim 2 , further comprising a second converter for converting the output of said second alternator, wherein said second converter has an output connected to said blower.  
   
   
       4 . An electric drive system for a vehicle according to  claim 2 , wherein said second alternator is controlled to generate a constant voltage independently of an engine rotation speed.  
   
   
       5 . An electric drive system for a vehicle according to  claim 2 , wherein said alternator and said second alternator are coaxially connected to an output shaft of said engine.  
   
   
       6 . An electric drive system for a vehicle according to  claim 1 , further comprising a transformer for transforming the output of said alternator, wherein said blower is driven by an output of said transformer.  
   
   
       7 . An electric drive system for a vehicle according to  claim 6 , further comprising a second converter for converting the output of said transformer, wherein said second converter has an output connected to said blower.  
   
   
       8 . An electric drive system for a vehicle according to  claim 6 , further comprising a switch for connecting the output of said transformer to said blower.  
   
   
       9 . An electric drive system for a vehicle according to  claim 1 , wherein a driving force is provided for said wheels by connecting a rotating force of said motor to said wheels through gears, or directly connecting to said wheels.  
   
   
       10 . An electric drive system for a vehicle according to  claim 1 , wherein said motor is connected to said resistor through said switch when said motor is driven by said wheels to generate electric power.  
   
   
       11 . An electric drive system for a vehicle according to  claim 1 , further comprising a second motor for cooling down said resistor, said second motor being driven with the electric power generated by said motor.  
   
   
       12 . An electric drive system for a vehicle according to  claim 1 , wherein said system determines whether or not said vehicle is in retard, and cools said resistor when said vehicle is in retard.  
   
   
       13 . An electric drive system for a vehicle according to  claim 12 , wherein said system determines whether or not said resistor is cooled down, and determines whether or not said vehicle is in retard after waiting for a predetermined time when said resistor is cooled down.  
   
   
       14 . An electric drive system for a vehicle according to  claim 13 , wherein said system determines whether or not said vehicle is in acceleration, and determines whether or not said vehicle is in retard when said vehicle is in acceleration.  
   
   
       15 . An electric control system for a vehicle for controlling electric power generated by an alternator driven by power of an engine, and controlling a conversion of a rectified version of the electric power output, wherein a torque of wheels driven by a motor is controlled by the converted electric power by controlling the conversion of the electric power, said motor is controlled to generate electric power which acts as a mechanical load on rotations of the wheels, and said system controls to cool down thermal energy generated by electric power generated by said motor.  
   
   
       16 . An electric drive method for a vehicle comprising the steps of: 
 rectifying electric power generated by an alternator driven by an engine;    converting the rectified output to an alternate current by a converter;    driving a motor with the converted output to rotate wheels;    driving said motor to generate electric power which acts as a mechanical load on rotations of the wheels; and    converting the electric power generated by said motor to thermal energy to dissipate the heat.    
   
   
       17 . An electric drive system according to  claim 1 , further comprising wheels mechanically coupled to said motor.