Motor system for remote electronic tilt antennas and methods for controlling same

A method for controlling the position and speed of a motor system for a multi-RET actuator system, the multi-RET actuator system comprising a plurality of drive assemblies, each drive assembly operatively connected to a phase shifter assembly such that movement of the drive assembly a total travel distance adjusts the respective phase shifter assembly to a target position, a direct current motor system coupled to the plurality of drive assemblies, the motor system comprising a rotor configured to rotate within an interior cavity of a stator, a drive shaft coupled to the rotor and to the plurality of drive assemblies, an annular disc surrounding the stator, the annular disc is coupled to the rotor such that rotation of the rotor causes simultaneous rotation of the annular disc;

• a plurality of spaced apart magnets embedded within the annular disc;
• and a HALL effect sensor, the method comprising:
• calculating a first intermediate distance and a second intermediate distance relative to the total travel distance of a selected drive assembly of the plurality of drive assemblies;
• accelerating rotation of the rotor and annular disc to move the selected drive assembly of the plurality of drive assemblies within the first intermediate distance;
• counting a step voltage produced by the HALL effect sensor as the rotor and annular disc rotate past the HALL effect sensor to calculate a current travel distance of the selected drive assembly;
• decelerating rotation of the rotor and annular disc when the current travel distance of the selected drive assembly reaches the second intermediate distance;
• calculating a dead-band region relative to the total travel distance of the selected drive assembly;
• shutting down the motor system when the total travel distance of the selected drive assembly is within the dead-band region;
• measuring the step voltage produced by the HALL effect sensor to determine if a counter-rotation of the rotor is detected after the rotor comes to a complete stop;
• and
• subtracting a distance added by the counter-rotation of the rotor from the total travel distance for the selected drive assembly to reach the target position.

A motor system for a multi-RET actuator system, the motor system comprising:

• a rotor configured to rotate within an interior cavity of a stator, the rotor comprises armature windings and the stator comprises field windings;
• a drive shaft coupled to the rotor and to a drive assembly of the multi-RET actuator system;
• an annular disc surrounding the stator, the annular disc is coupled to the rotor such that rotation of the rotor causes simultaneous rotation of the annular disc;
• a plurality of spaced apart magnets embedded within the annular disc;
• a HALL effect sensor;
• and
• a motor speed controller in communication with the rotor and the HALL effect sensor, the motor speed controller comprising:
• a proportional integral derivative (PID) speed controller configured to control a PWM output to the rotor;
• an edge detector in communication with the HALL effect sensor to detect when the magnets rotate past the HALL effect sensor;
• and
• a step counter configured to count a step voltage produced by the HALL effect sensor.