Control system for brushless DC ring motor cooling fan

Abstract

A cooling system for a vehicle includes a cooling fan assembly having a cooling fan driven by a brushless DC ring motor, a control/communications system operatively connected to an engine control module (ECM) of the vehicle, a DC-to-DC converter operatively connected to a power source, and a commutation switching segment operatively connected to the DC-to-DC converter and to the control/communications system to provide signals for operating the brushless DC ring motor.

1 . A cooling system for a vehicle, the cooling system comprising: 
 a cooling fan assembly attached to a fixed portion of the vehicle, the cooling fan assembly including a cooling fan driven by a brushless DC ring motor;    a control/communications system operatively connected to an engine control module (ECM) of the vehicle;    a DC-to-DC converter operatively connected to a power source; and    a commutation switching segment operatively connected to the DC-to-DC converter and to the control/communications system, the commutation switching segment being connected to provide signals for operating the brushless DC ring motor of the cooling fan assembly.    
   
   
       2 . The cooling system of  claim 1 , wherein the control/communications system is operable to receive pulse width modulated (PWM) signals from the ECM of the vehicle to control the brushless DC ring motor.  
   
   
       3 . The cooling system of  claim 1 , wherein the control/communications system is operable to receive digital signals from a serial line of the ECM of the vehicle to control the brushless DC ring motor.  
   
   
       4 . The cooling system of  claim 1 , wherein an output of the DC-to-DC converter is variable for gross adjustment of a speed of the motor and an output of the commutation switching segment is variable for fine adjustment of the speed of the motor.  
   
   
       5 . The cooling system of  claim 1 , wherein the power source is a vehicle battery.  
   
   
       6 . The cooling system of  claim 5 , wherein the DC-to-DC converter is operable to selectively draw power from the vehicle battery in demanding cooling conditions.