Method for controlling an electric drive machine

Abstract

A method is provided for controlling an electric drive work machine including an engine and an electric motor that provides power to enable the work machine to travel across a surface terrain at certain ground speeds. In one embodiment, the method may include detecting a reverse directional shift of the work machine causing the work machine to travel in a reverse direction. Further, the method may include performing an engine speed reduction process that reduces a current speed of the engine based on the detected reverse directional shift without reducing a ground speed of the work machine while traveling in the reverse direction.

1 - 27 . (canceled)  
   
   
       28 . A method for controlling an electric drive machine including an engine and an electric motor that provides power to enable the machine to travel across a surface terrain at certain ground speeds, the method comprising: 
 detecting a reverse directional shift of the machine causing the machine to travel in a reverse direction; and    performing an engine speed reduction process that reduces a current speed of the engine based on the detected reverse directional shift without reducing a ground speed of the machine while traveling in the reverse direction.    
   
   
       29 . The method of  claim 28 , wherein the method further includes: 
 determining whether the machine is experiencing a load while traveling in the reverse direction; and    disabling the engine speed reduction process when the machine is experiencing a load while traveling in the reverse direction.    
   
   
       30 . The method of  claim 28 , further including: 
 determining whether the ground speed of the machine exceeds a predetermined threshold speed value; and    bypassing the engine speed reduction process when the ground speed of the machine does not exceed the predetermined threshold speed value.    
   
   
       31 . The method of  claim 30 , further including: 
 determining whether the machine is experiencing a load while traveling in the reverse direction; and    disabling the engine speed reduction process when the machine is experiencing a load while traveling in the reverse direction.    
   
   
       32 . The method of  claim 29 , wherein determining whether the machine is experiencing a load while traveling in the reverse direction includes: 
 determining that the machine is backing up on a sloped terrain surface.    
   
   
       33 . The method of  claim 29 , wherein determining whether the machine is experiencing a load while traveling in the reverse direction includes: 
 determining that the machine is manipulating a load while traveling in the reverse direction, wherein manipulating the load includes at least one of pushing the load, pulling the load, and carrying the load.    
   
   
       34 . The method of  claim 28 , wherein performing the engine speed reduction process includes: 
 determining an adjusted engine speed based on at least one of the current speed of the engine and the ground speed of the machine; and    generating a control signal that reduces the current speed of the engine to the adjusted engine speed.    
   
   
       35 . The method of  claim 34 , wherein performing the engine speed reduction process further includes: 
 allowing the motor of the machine to produce sufficient power to at least maintain the ground speed of the machine while traveling in the reverse direction.    
   
   
       36 . A method for controlling an electric drive machine including an engine and an electric motor that provides power to enable the machine to travel across a surface terrain at certain ground speeds, the method comprising: 
 detecting a directional shift of the machine causing the machine to operate in a new directional cycle that is different from a current directional cycle; and    performing an engine speed adjustment process that adjusts a current speed of the engine based on the detected directional shift without adjusting a ground speed of the machine during the new directional cycle.