Electro-hydraulic components are essential part of hydraulic system. These components are used widely. Servo valve and proportional valve is driven by electro-hydraulic components i. e . Torque motor, linear force motor, solenoid etc. Sensor are used as feedback in servo system. Lvdt is used as position sensor and lvt is used as velocity sensor. An electro hydraulic system consists of an electric system, a hydraulic system, and a means whereby the electric and hydraulic systems can interact. After introducing the working principle of torque motor, the dynamic mathematical model of torque motor is presented. Simulation of torque motor is also done in matlab. Linear force motors in direct-drive servo-proportional valves provide numerous benefits over traditional solenoids. These include: higher frequency response, greater spool-driving force, and lower power consumption. A mathematical model of linear force motor is developed and then simulated by simulink on computer.