Unbalance - Symmetrical Components
A balanced system has a 120° phase shift between the voltages and currents, and the voltages and currents have the same amplitude respectively. Unbalance happens when the 3 phase system is loaded unevenly, and the phases and magnitudes no longer correlate.
To analyze an unbalanced system, the symmetrical components calculation method is used. This method splits the original unbalanced 3 phase power system into a positive system (rotation like the original system), the negative system (rotation in the reverse direction), and a zero system.
An unbalanced system could cause current to flow in the neutral line, overheating electrical components, mechanical stress, increased vibration, and torque pulsation, low power quality, and energy losses among others.
Dewesoft’s Power Meters can measure over 50 parameters for a comprehensive analysis of an unbalanced system. These parameters include various calculations for voltage, current, active-, reactive-, apparent power as well as harmonics.