Sweep Frequency Response Analysis (SFRA)

Frequency response analysis (often referred to as FRA or SFRA) is a powerful and sensitive method for testing the mechanical integrity of transformer cores, windings, and press frames, in power transformers.

Every electrical network has a unique frequency response – its so-called "fingerprint". Network faults or vibrations can cause changes in this frequency response.

Comparing the measurements taken at various phases or on multiple identical transformers, as well as comparing measurements with the former fingerprint of the same transformer, provide indications of any mechanical or electrical changes.

We recommend testing the frequency response particularly after transporting transformers and after faults at high currents have occurred. You can use our testing solution for checking if windings have been damaged and then initiate any further action that may be necessary.

Recommended solutions for SFRA measurements on power transformers


Core and winding diagnosis