The shaft voltage of a rotary generator is caused by the magnetic imbalance in the generator. The magnitude of the shaft voltage varies with the voltage and load of the generator. When the shaft voltage exceeds the damage value of the oil film, the shaft current will increase rapidly, which will cause severe damage in the bearing in a short period of time. This current can exceed 100A. However, even small currents of only a few amps can cause considerable damage to the bearings.
In order to prevent the occurrence of shaft current, reinforced insulation at the bearing end is generally adopted as a measure to prevent shaft current, but the problem cannot be solved at all. In the event of bearing insulation damage, unpredictable serious consequences will still occur, which will directly lead to bearing bush burnout, deterioration of oil quality, and increased bearing vibration. For this reason, we have developed a new AECM-III shaft current protector, which is a perfect way.