Design Of Digital AC Servo System

AC servo has many advantages such as smaller weight,higher efficiency,more moment exporting,lower noises and higher credibility. So it has been used more and more widely in the motion control field.Practice shows: AC servo system which uses AC servo motors is a nonlinear system, A good control strategy is very important to improve system's performance.AC motor is a high order, nonlinear, coupling ystem, so the control strategy is mostimportant in AC servo systems.The paper researchs the control strategies of AC servo system and has done four works:1.Discuss a way that how to get maximum moment when current has been set with detailed computation.It introduces that how to get the result.Through discussing motor'sρ=1 or not,we can calculate the best control angle.The system's efficient and performance are developed hardly. The current is reduced too.2.When the parameter variations in AC drive systems is very hard, a single control strategy can hardly get ideal control effect. To overcome this disadvantage, we mix PID control with fuzzy control and put parameter fuzzy self-tunning into system. It introduced detailly the means how to get Kp,Ki,Kd through the position error and position error.Then put them into PID control part to get good control effect.After testing,we confirm that the system's control performance and brustless are developed hardly.3.The paper discusses some ways that how to reduce the AC servo system's EMI.The paper introduces several fields such as cover,ground and layout around EMI theory and tests these ways by experiments.After testing, we confirm that these ways are available and have some guildance meaning.4.At last the paper introduces that hardware and software's flowchat and over-voltage protection of the system. After long time running,we confirm the protection works well and is fit for the system.