INVESTIGATION OF THE EFFECTS OF CURRENT MEASUREMENT METHODS ON SERVO MOTOR DYNAMICS
Özet
Electric Drive Applications, which we actively use in our daily lives, increase the usage area with developing technology. In order to increase the efficiency of these applications and to control the motors more accurately; measurement of motor currents with less loss, accuracy and reliability of measurements, cost of design are important design criteria in motor control systems. There are two main reasons why motor currents need to be measured with high accuracy and appropriate bandwidth. The first is to provide information to the controller with minimal delay when the overcurrent condition occurs in the motor phases and the other is to optimize the dynamic responses of the physical variables (position, speed, torque). In this study, the effects of different criteria such as proper bandwidth, maximum accuracy and linearity according to temperature change on servo motor systems were investigated. Fault tolerance and power loss analyzes in measuring motor current with shunt resistor or closed loop Hall Effect sensor are also compared. The bandwidth of the current measuring circuits was measured by oscilloscope. The measured bandwidth was used in the feedback transfer function. Finally, in the current measurement method with resistance; when torque reaches its rated torque, two percent more overshoot occurs.