25/51 4.3 Relative Displacement:Translational and Rotational V.Synchros(同步机)and Resolvers Synchros:a type of rotary electrical transformer that is used for measuring the angle of a rotating machine such as an antenna platform. Synchros for angle measurement are most utilized as components of servo- mechanisms (automatic motion-control feedback systems)where they are used to measure and compare the actual rotational position of a load with its commanded position as shown in Figure 4.24. Resolvers basically "Resolve"the rotary motion of a rotor into the sine and cosine of the rotor angular position,providing two AC output voltages whose amplitude are proportional,respectively,to the sine and cosine. 26/51 4.3 Relative Displacement:Translational and Rotational V.Synchros(同步机and Resolvers Load 35, Gearing ac excitation frequency WexR 5 ac motor Synchro control R2 transmitter ac o amplifier ● ● ee =Ke(Ge-0g)sin Wext Synchro control transtormer 5i,S2,53 are stator coils(定子线圈) R,R,are rotor coils(转子线圈) Figure 4.24 AC Servomechanism4.3 Relative Displacement: Translational and Rotational V. Synchros(同步机) and Resolvers Synchros: a type of rotary electrical transformer that is used for measuring the angle of a rotating machine such as an antenna platform. Synchros for angle measurement are most utilized as components of servo￾mechanisms (automatic motion-control feedback systems) where they are used to measure and compare the actual rotational position of a load with its commanded position as shown in Figure 4.24. Resolvers basically “Resolve” the rotary motion of a rotor into the sine and cosine of the rotor angular position, providing two AC output voltages whose amplitude are proportional, respectively, to the sine and cosine. 25/51 (定子线圈) (转子线圈) V. Synchros(同步机) and Resolvers Figure 4.24 AC Servomechanism 4.3 Relative Displacement: Translational and Rotational 26/51