PROTECTION OF DC MOTORS FROM FIELD FAILURE - A SURVEY

Field failure protection of dc motor has gained a great demand as it's a topic of essence. Purpose of field failure relay is to protect the motor from the damage of field failure. This paper presents a comprehensive review of various methods of speed control and field failure protection. Firstly, the principles of op-amp and chopper will be briefly presented. Secondly, the employment of the op-amp in a field failure protection will be outlined. The concept of op-amp in field failure protection can be extended for application to different DC motor such as: series, separately excited and permanent magnet DC motor.