Modeling and analysis of servo valve torque motor based on FEM

Abstract

The paper investigates the servo valve torque motors in electro-hydraulic servo valves. Through numerical simulation of three-dimensional electromagnetic field, the intrinsic relationship of between the output torque and input current & armature angles has been studied in-depth. The achieved formula to the actual torque motor has a high reference value for the control of electro-hydraulic servo valve. In the actual use of toque motor, it's difficult to avoid the assembly error. So, the influence of assembly error on output torque of the torque motor is analyzed for the first time in detail in this paper. The traditional magnetic field simulation is carried out under the default room temperature conditions, while ignoring the influence of ambient temperature for the permanent magnet. The paper also investigates the influence of different ambient temperature on the magnetic characteristic and output torque of the motor.