Overvoltage Minimization in Induction Motors employing Long Cable PWM Drives

The employment of PWM drives in induction motors control has been widely used in industry. However, in some applications in hazardous areas, such as drilling, the PWM drive cannot be physically close to the motor, being necessary the use of long cable drives. This fact leads to the generation of overvoltage peaks on the induction motor terminals, which can cause interference in the speed control, reduction of equipment lifetime, or even, permanent damages. In this context, this work presents alternatives to minimize the overvoltage effect based on the use of transformers and analyzes the performance of the speed control of each proposed technique.