Patent ID: 7192005

Claim:
A method for stabilizing operating characteristics of a solenoid-operated fluid pressure control valve system in a control valve circuit, the control valve system comprising a solenoid actuator having a stator coil, an adjustable armature responsive to electromagnetic forces and an opposing spring force, and a fluid pressure regulator valve element coupled to the armature, the method comprising: applying a base actuating current to the stator coil to effect control of pressure by the control valve system; establishing an electrical dither frequency for the base actuating current to effect compliance of the control valve system as a function of electrical dither frequency as fluid pressure is controlled in response to a pressure command; and changing the electrical dither frequency at regulated pressure values within a precalibrated range of regulated pressure values whereby instability of the valve system is avoided; the electrical dither frequency being established at a value that exceeds a natural frequency for the solenoid actuator; the step of changing the electrical dither frequency comprising interrupting it when regulated pressure values are within the precalibrated range.