Does anyone have experience with using LIRA (Line Impedance Resonance Analysis) for cable testing & has compared the results with TDR, VLF tan delta & partial discharge?
We are doing the latter & client wants a comparison. To my understanding, LIRA can detect physical damage to the cable but...
I am looking for a supplier for TVA/Corona Probe, other than Iris. The Iris instrument cannot be used beyond 6.9 kV. I need to localize the PD on the individual generator bars. Any feedback would be most appreciated.
Regards,
Aditya
Currently overhauling a 110 MW generator at client’s site. Major observations as under:
1. Rotor has an interturn short – impedance is reduced by 17 % compared to the factory values. Surge waveform shows separation when tested from either end (+ve & -ve). Cleaning did not help.
2. Generator...
Our company has decided to purchase a PD Analyzer to enhance our diagnostic capabilities on generators & motors. Currently, we use tan delta, AC & DC hipot, surge and IR, PI & DD.
I have got offers from Tettex, Iris, PD Tech, Power Diagnostix, Adwel, M & B Systems and Cutler Hammer. However; I...
Does anyone have experience in performing the DC Absorption Test & its analysis?
I know it involves applying 2.5/5 KV DC to the winding insulation & recording the charging current for a set period (typically 1000 seconds) & then discharging through an external resistor for the same period...
Case study - 34 MW generator, was not generating sufficient reactive power. Checked at FSNL, PMG current is 12 A (typically 4A). Checked all points, found main rotor IR = 0 M?.
Rotor threaded out & DC voltage drop test conducted on rotor (DC to winding, checked drop between winding & ground)...
I have been doing tan delta testing of motors for many years now. While there are standards for new coils, I am yet to come across any standard for the complete motor. Also, never seen any limiting values for old motors. Does anybody have some references?
Regards,
Aditya
