Two wire position sense and control of modulating gas valve or other electromechanical actuators

A method of controlling an electromechanical actuator assembly including an actuating member associated with an electrical coil, wherein selective energization of the coil with a command signal indicative of a desired position for the actuating member effects a corresponding movement of the member towards a desired position, the method comprising steps of:

• energizing the coil with a control signal through an electrical line to effect the corresponding movement of the actuating member from a first position to a second position,
• concurrently energizing the coil with a detection signal through the electrical line for generating detectable signals,
• sensing the detectable signals through the electrical line for associating a first detectable signal from said detection signal with said first position and for associating a second detectable signal from said detection signal with said second position,
• detecting a measurement representative of a difference between the second position and the desired position, and
• adjusting the control signal to minimize the difference measurement whereby a position of the actuating member is determined and controlled through the electrical line.