EMF Software Options for Underground Circuits

[cyriousn]

Does anyone have a recommendation for EMF study software besides using CYME? We are having a hard time justifying 30k for a software license and looking for some good alternatives. Thanks!

 

[DBL-E]

When you are looking at EMF studies, what are you looking to see as a result of a study? If you are looking at underground circuits, its really just the magnetic field that propagates, and then you consider proximity of the phases having cancelation of each other's fields. I see Cyme as a magnetic fields add on to cymcap, but certainly appreciate better understanding the application.

xgslab has a couple modules that are used for EMF studies, such as GIS voltages for hand-to-hand voltages, induction on pipelines/railroads in corridors with transmission lines, and can model circuits underground.

 

[cyriousn]

We are using it to measure the field strength for 34.5kv circuits along roadways for a PV project. We are planning on picking up the magnetic field module with CYMCAP so it sounds like we should be okay with that software package.

 

[DBL-E]

OK, I would recommend you ask them about the specific cables you are using before doing a purchase. The only part that caught my attention is in the website it says 'the induced currents are neglected', which if you have a concentric neutral or dedicated ground conductor that is a significant difference in the fields. If you are just calculating the fields for each phase (omitting induced current of other things) you may be able to do some hand calculations (there are a lot of vectors to keep track of). That said if you are just looking for a maximum value, if you calculate a single phase, it will be a greater magnitude, then all three phases as they balance/reduce the field. Also I ran across this EE Portal EMF Calc Sheet

I'm guessing this is just to verify fields are below a state required level in a ROW and when you exceed that limit you either run in a metal conduit, bury deeper, or add a ground wire above to induce opposit current/magnetic fields.

 

[cyriousn]

Thanks for the heads up on induced currents. Yes we will be using to verify they are below the NY state required levels.

Some example projects that are in the process of being submitted can be found at the link below. Each submission should have an Appendix 22 for the EMF study.

https://ores.ny.gov/permit-applications