Electric motor drive controller with voltage control circuit operative in different modes

Abstract

An electric motor drive controller for an electric vehicle driven by a motor with permanent excitation and powered by an energy source comprises: a power control stage coupleable to the motor for generating a drive signal at a voltage to control the motor at a desired speed; a voltage control circuit connectable between the energy source and the power control stage for controlling the voltage of the drive signal at a first voltage potential in one operating mode and at a voltage potential greater than the first voltage potential in another operating mode; and a mode controller for controlling the operating modes of the voltage control circuit based on properties of the drive signal.

1 - 20 . (cancelled)  
   
   
       21 . An electric motor drive controller for an electric vehicle driven by a motor with permanent excitation and powered by an energy source, said motor drive controller comprising: 
 a power control stage coupleable to said motor for generating a drive signal at a voltage to control said motor at a desired speed;    a voltage control circuit connectable between said energy source and said power control stage for controlling the voltage of said drive signal between a first voltage potential and a voltage potential greater than said first voltage potential; and    a sensing circuit for monitoring said drive signal, said sensing circuit being coupled to said voltage control circuit for governing the control of said drive signal voltage.    
   
   
       22 . The motor drive controller of  claim 21  wherein the energy source produces energy at a voltage potential; and wherein the first voltage potential is substantially the voltage potential of the energy source.  
   
   
       23 . The motor drive controller of  claim 21  wherein the sensing circuit generates a signal indicative of the condition of the drive signal; and wherein the voltage control circuit is operative to control the voltage of said drive signal in response to said sensing circuit signal.  
   
   
       24 . The motor drive controller of  claim 23  wherein the voltage control circuit is operative to couple the energy source to the power control stage so long as the sensing circuit signal indicates that the drive signal can control the motor at the desired speed.  
   
   
       25 . The motor drive controller of  claim 23  wherein the voltage control circuit is operative to conduct the first voltage potential to the power control stage so long as the sensing circuit signal indicates that the drive signal can control the motor at the desired speed.  
   
   
       26 . The motor drive controller of  claim 25  wherein the voltage control circuit is operative to increase the voltage conducted to the power control stage above the first voltage potential when the sensing circuit signal indicates that the drive signal can no longer control the motor at the desired speed.  
   
   
       27 . The motor drive controller of  claim 26  wherein the voltage control circuit is operative to increase the voltage conducted to the power control stage above the first voltage potential in incremental steps when the sensing circuit signal indicates that the drive signal can no longer control the motor at the desired speed.  
   
   
       28 . The motor drive controller of  claim 27  wherein the voltage control circuit is operative to increase the voltage conducted to the power control stage above the first voltage potential at fixed incremental steps when the sensing circuit signal indicates that the drive signal can no longer control the motor at the desired speed.  
   
   
       29 . The motor drive controller of  claim 27  wherein the voltage control circuit is operative to increase the voltage conducted to the power control stage above the first voltage potential at variable incremental steps when the sensing circuit signal indicates that the drive signal can no longer control the motor at the desired speed.  
   
   
       30 . The motor drive controller of  claim 21  including an inhibit circuit for inhibiting the voltage control circuit from increasing the voltage conducted to the power control stage above the first voltage potential based on motor current.