Methods and systems for automatic rotation direction determination of electronically commutated motor

Abstract

A method for determining a direction of rotation for an electronically commutated motor (ECM) is described. The motor is configured to rotate a blower and the method comprises rotating the blower using the ECM and determining if the resulting blower rotation is indicative of the desired direction of rotation for the blower.

What is claimed is: 
     
         1 . A motor controller configured to control an electric motor, the electric motor configured to rotate a blower, said motor controller comprising a processor configured to:
 cause the electric motor to rotate the blower in a first direction at a predefined amount of applied torque during an initial power-up of the electric motor;   determine a first speed of rotation of the blower when the blower is rotated in the first direction;   rotate the blower in a second direction, opposite the first direction, at the predefined amount of applied torque;   determine a second speed of rotation of the blower when the blower is rotated in the second direction; and   determine whether the first direction corresponds to a proper direction of rotation of the blower based on the first speed of rotation and the second speed of rotation.   
     
     
         2 . The motor controller of  claim 1 , wherein said processor is further configured to compare the first speed of rotation and the second speed of rotation. 
     
     
         3 . The motor controller of  claim 2 , wherein said processor is further configured to determine the first direction is the proper direction of rotation when the first speed of rotation is less than the second speed of rotation. 
     
     
         4 . The motor controller of  claim 2 , wherein said processor is further configured to determine the second direction is the proper direction of rotation when the second speed of rotation is less than the first speed of rotation. 
     
     
         5 . The motor controller of  claim 1 , wherein said processor is further configured to store the proper direction of rotation in a memory device communicatively coupled to said processor such that the electric motor rotates the blower in the proper direction of rotation during subsequent power-ups after the initial power-up of the electric motor. 
     
     
         6 . The motor controller of  claim 1 , wherein the blower is a forward curved blower. 
     
     
         7 . The motor controller of  claim 1 , wherein the electric motor is an electronically commutated motor (ECM). 
     
     
         8 . A method for controlling an electric motor, the electric motor configured to rotate a blower, said method comprising:
 causing the electric motor to rotate the blower in a first direction at a predefined amount of applied torque during an initial power-up of the electric motor;   determining a first speed of rotation of the blower when the blower is rotated in the first direction;   rotating the blower in a second direction, opposite the first direction, at the predefined amount of applied torque;   determining a second speed of rotation of the blower when the blower is rotated in the second direction; and   determining whether the first direction corresponds to a proper direction of rotation of the blower based on the first speed of rotation and the second speed of rotation.   
     
     
         9 . The method of  claim 8 , further comprising comparing the first speed of rotation and the second speed of rotation. 
     
     
         10 . The method of  claim 9 , further comprising determining the first direction is the proper direction of rotation when the first speed of rotation is less than the second speed of rotation. 
     
     
         11 . The method of  claim 9 , further comprising determining the second direction is the proper direction of rotation when the second speed of rotation is less than the first speed of rotation. 
     
     
         12 . The method of  claim 8 , further comprising storing the proper direction of rotation in a memory device such that the electric motor rotates the blower in the proper direction of rotation during subsequent power-ups after the initial power-up of the electric motor. 
     
     
         13 . The method of  claim 8 , wherein the blower is a forward curved blower. 
     
     
         14 . The method of  claim 8 , wherein the electric motor is an electronically commutated motor (ECM). 
     
     
         15 . A method for controlling an electric motor, the electric motor configured to rotate a blower, said method comprising:
 causing the electric motor to rotate the blower in a first direction at a predefined speed of rotation during an initial power-up of the electric motor;   determining a first amount of torque to rotate the blower in the first direction at the predefined speed of rotation;   rotating the blower in a second direction, opposite the first direction, at the predefined speed of rotation;   determining a second amount of torque to rotate the blower in the second direction at the predefined speed of rotation; and   determining whether the first direction corresponds to a proper direction of rotation of the blower based on the first amount of torque and the second amount of torque.   
     
     
         16 . The method of  claim 15 , further comprising comparing the first amount of torque and the second amount of torque. 
     
     
         17 . The method of  claim 16 , further comprising determining the first direction is the proper direction of rotation when the first amount of torque is greater than the second amount of torque. 
     
     
         18 . The method of  claim 16 , further comprising determining the second direction is the proper direction of rotation when the second amount of torque is greater than the first amount of torque. 
     
     
         19 . The method of  claim 15 , further comprising storing the proper direction of rotation in a memory device such that the electric motor rotates the blower in the proper direction of rotation during subsequent power-ups after the initial power-up of the electric motor. 
     
     
         20 . The method of  claim 15 , wherein the blower is a forward curved blower.