Shielding of Cables in substation

[ePOWEReng]

Does anybody have experience or know of options on how to shield cables that are near high frequency, high magnitude currents? Coupling from Capacitor switching currents is creating short duration, high frequency, high magnitude voltages(1000 Volts phase-neutral) on some PT cables that are running back to the panel house across the substation.

 

[busbar]

From a standards/boilerplate perspective, there is IEEE text
525-1992(R1999) §3 in …Design and Installation of Cable Systems in Substations
1050-1996 §6 in …Instrumentation Control Equipment Grounding in Generating Stations

Descriptions at
standards.ieee.org/reading/ieee/std_public/description/subst/525-1992_desc.html
standards.ieee.org/reading/ieee/std_public/description/nuclear/1050-1996_desc.html

 

[jghrist]

See
Reduction of interference on substation low voltage wiring; Gavazza, R.J. & Wiggins, C.M.; IEEE Transactions on Power Delivery, Volume: 11, Issue: 3, July 1996, Pages:1317 - 1329.

Abstract:
This paper describes test results and mitigation methods of electromagnetic interference (EMI) on control and low voltage circuits in substations caused by air disconnect switch operation. The tests are focused on a comparison between unshielded and shielded circuits from capacitively coupled voltage transformers (CCVT) and other equipment circuits in the vicinity. New test data are presented comparing unshielded and shielded cables and transient currents on all connections to the CCVT including the pedestal and ground strap. The paper gives a practical and understandable explanation of the causes of EMI in substations and how shielded cable and parallel ground conductors reduce interference. Design guidelines are listed in the conclusion.