Reactor Failure

[Chyep]

Recently a customer of ours had a failure on his capacitor bank. The Iron core reactors used to detune his capacitors have literally ripped apart at the magnetic gap. I'm suspecting a transient of some considerable size is responsible. Is this possible or is it a manufacturing defect?

 

The capacitors and reactors have been double checked and they are correctly matched. i.e. Tuned well below the 5th harmonic order.

 

Thanks.

[Chyep]

Recently a customer of ours had a failure on his capacitor bank. The Iron core reactors used to detune his capacitors have literally ripped apart at the magnetic gap. I'm suspecting a transient of some considerable size is responsible. Is this possible or is it a manufacturing defect?

 

The capacitors and reactors have been double checked and they are correctly matched. i.e. Tuned well below the 5th harmonic order.

 

Thanks.

lol

62 views and no replies. Safe to say no one else has seen it either. I'm starting to thing that this is a reactor problem. I suspect the laminations in the reactor core became conductive, Eddie currents within the core then heated and destroyed the air gapping material causing a change in tuning frequency and then resonance. the heating is consistent throughout the entire bank and B phase, which would be the most susceptible to a heat build up consistently showd the most signs of heating.

 

[Clayts]

I concur

 

 

Well..actually a picture would help, A picture of the Iron core reactors used to detune his capacitors that literally ripped apart the magnetic gap would be extremely useful.

 

 

I'd seperate and revarnish the laminations. If that fails then ask Marke!

 

 

[marke]

I would be very surprised if it is a transient.

A photo would help.

Is there any sign of heating in the winding?

 

Best regards,

Mark.

[siowpt]

Recently a customer of ours had a failure on his capacitor bank. The Iron core reactors used to detune his capacitors have literally ripped apart at the magnetic gap. I'm suspecting a transient of some considerable size is responsible. Is this possible or is it a manufacturing defect?

 

The capacitors and reactors have been double checked and they are correctly matched. i.e. Tuned well below the 5th harmonic order.

 

Thanks.

What is the harmonic level (Vthd and Ithd) at that particular PCC.

[Chyep]

I don't believe it was harmonic overload, because the capacitors all survived. They all draw rated current when bench tested. The reactor windings don't look damaged, but the cores have all been seriously hot. The air gaps which are glastic in this case are cooked and reduced to stringy fiber. the heat actually discolored the label radiating from the center phase. The heat migrated from the core to the windings and melted the TEW insulation on the cables.

 

I've got a picture somewhere. I'll have to see if I can find it before I can post it. Tell tale to me is the capacitors all surviving. If it was harmonic overload, they would be the first thing to fail. Unfortunately I do not have a harmonic footprint from the PCC, but do know that the utility is within their guide lines.

[Chyep]

It's been awhile since I've been here, so I thought I'd close out this thread for anyone interested. It seems the reactors were not built to specification. They were capable of withstanding the fundamental current of 60 Amps but not the RMS current requested of 72Amps. Somewhere in the middle the cores overheat leading to damaged insulation and eventual failure.