Localized Voltage Unbalance and Harmonics Correcting Circuit

Squirrel cage induction motors are used in machines that are sensitive to voltage fundamental component unbalances and voltage harmonics. This invention uses a Voltage Unbalance Compensator (VUC) inserted in the motor neutral to correct for these disturbances. This compensator is a low cost means of maintaining 100% motor load capability even in the presence of a 5% unbalance and can stop harmonic current flow within the machine. By using the VUC, the motor can be controlled to present itself as a unity power factor load to the utility regardless of the loading condition of the motor.