The microcomputer harmonic elimination device of the substation is installed on the secondary side of the PT cabinet, which circularly detects and diagnoses the triangular voltage at the opening of the voltage transformer, and judges whether the system has grounding, over-voltage, and resonance faults. When the diagnosis system has ferromagnetic resonance, the high-power harmonic elimination element is quickly put into use, so that the ferromagnetic resonance can be quickly eliminated under the effect of damping.

The microcomputer harmonic elimination device is mainly composed of sampling element, harmonic elimination element, central control unit, LCD, micro printer, etc. Microcomputer harmonic elimination has the characteristics of low operation cost and easy maintenance, and a system only needs to install a microcomputer harmonic elimination device.