The Structure Design And Characteristic Study Of Hybrid Linear Force Motor

As a kind of linear motor, linear force motor usually is used as an actuator in positioning or switching control system for hydrometric servo valves and so on. The hybrid (or permanent magnet) linear force motor is excited by both coil and permanent magnet. The flux due to permanent magnet is the main part of gap flux, the rest flux is produced by the winding coil, which play a part of regulation.So far, the references about the hybrid linear force motor are not plenty. The purpose of this thesis is to design a kind of linear force motor mainly used as actuator of direct drive valve for accurate positioning, to regulate liquid flow accurately. Under the condition of small placement with a suitable spring adopted, the force is approximately proportional to coil current. Therefore, the output force may be directly regulated by regulating coil current. According the different value between the input position voltage and feedback LVDT voltage and using the PID position controller, the motor current is pulse-width modulated by a DC motion...