الفهرس | Only 14 pages are availabe for public view |
Abstract The problem of mechanical resonance in modern servo motor drives systems is presented, which happen when servo motor faces sudden load, straightforward assemble guidelines and results of experimental verification obtained by an experimental setup with rigged load coupled to servo motor for different speed and different voltage. Motors were classified to two main kinds of motors ; AC, DC motors. We will discuss many types of ac and dc motors comparing the advantages and disadvantages of each. The AC motors can classified to Induction motors and synchronous motor where Induction motors are available in an extremely wide size range from very small units to hundreds of kW. The synchronous motor is basically the same as the induction motor but with slightly different rotor construction. Synchronous motor can be used in a speed control system even though a feedback device must be added. The DC motors classified to a lot of kinds as Permanent magnet (PM) motors which are probably the most commonly used motors and shunt, series, compound wound motors. There are several types of servo motors as Stepper motor which rotate, by constantly turn on and off the coils. If we simply energize coils the motor will just jump to other position and stay there without change till receiving another signal. Electrical motors operate on the principle that two magnetic fields within certain prescribed areas reacts upon each other. All electric motors use electromagnetic fields to create torque. For many motion engineers, motor iv selection plays a central part in getting good device performance .Knowing which motor to use in a given application improves the cost, performance, and simplicity of our machine-design process. Servo motor is works by pulse width modulation (PWM). The PWM is a power regulating technique by applying pulses of variable width. We must discus the effect of the torque on the motor where there is a direct relation between mass of load and torque this mean that torque equal mass multiplied by constant then unit mass mean unit torque. Servo motor is the best motor to use due to its advantages so, with a lot of applications but the main problem on servo motors system as all kinds of motors when motors are subjected to sudden loads (as the load varies continuously in many practical applications that uses precise servo motors,) considerable tensional oscillations and disturbances may alter the motors performances. In this thesis the sudden load affecting the motors behaviour and how to reach an optimized compensation have been studied. The practical work that demonstrating how to improve the motor behavior by assembling a circuit of electronic feedback and driving card will be present. |