50 Hz & 60 Hz Magnetic Field Profiles
We provide plane-view and elevation view simulation building modeling during 50% and 75% building loads. These models show the magnetic field emissions profile as a function of magnitude and distance from the various electrical sources.
Source modeling shows individual electrical elements and the potential impact on nearby sensitive EMI instrumentation and equipment.
Simulated future underground train and subway commuter tunnels can impact adjacent buildings with EMI sensitive instrumentation. The figure below shows a 25 kVA traction current underground catenary rail system emission profile.
The figure below shows an elevated third-rail 600 VDC electrified train adjacent to a medical research building.
We use DC to 500 Hz electrified train and 50/60 Hz power frequency software to generate electric (E-field) and magnetic (H-field) simulated plots. Such power systems include: field plots of transmission and distribution lines, substations, transformers, primary and secondary feeders, network protector busses, switchgears, electrical panels, conduits/risers and electrified trains.
We have modeled electrified, third rail and catenary AC/DC trains in Ireland, United Kingdom, Ottawa, New York and Boston.
We model antenna farms, cell towers, single and phased arrayed emitters, radars, microwave terrestrial and satellite communication systems. Field plots include electric field strength levels in V/m, specific absorption radio (SAR) in milliwatts per centimeter squared, and effective radiated power (ERP).
Our software team of engineers and programmers use finite element modeling (FEM) software, to accurately solve 2-D & 3-D complex magnetic transient AC electromagnetic, magnetostatic and circuit modeling. To demonstrate our concept shield design, we simulated magnetic field emission models of AC ELF 50/60 Hz utility and building distribution systems and predicted shielding effectiveness based upon our recommended shield designs.
3-D finite element model (FEM) simulation of energized network protectors, secondary feeders, and switchgear below a first floor office area. This FEM 2-D sliced 3-cross section simulation is similar to the actual recorded magnetic field levels of 198 mG RMS at 1-meter and 612 mG RMS on the floor.
After shield simulated models show 5 mG RMS or less compliance for human health exposure on the floor and at 1-meter.
Side by side FEM 3-D magnetic field comparison using ANSYS Maxwell and Surfer Voxler to simulate BIM EMF Modeling of unshielded and shielded MER with 75% energized transformers, network protectors, secondary feeders, switchgears, and distribution panels. Constructing electrical distribution model in ANSYS Maxwell, generating 3D simulation of 60 Hz magnetic field model, importing Maxwell 3-D with Revit/Navisworks building simulation models into Voxler to generate 3-D animation requires weeks of computational and programming time. Although the unshielded and shielded FEM 3-D animation looks impressive it is labor intensive to modify and implement small electrical and building design changes into the large and complex BIM model and re-simulate to generate another 3-D animation to evaluate EMI impact.
Planning your facility around various MRI requirements can be challenging. Some MRI equipment manufacturers require that the MRI 3 or 5 gauss isolines do not intersect with adjacent MRI systems. Others recommend even stricter requirements. Medical industry protocol requires posting of 5 Gauss Warning Signs in public and patient areas where potential exposure to the MRI 5 Gauss isoline could compromise implantable devices. While this information is determined by closed bore or open bore superconducting magnets, EMI design criteria for building sites, health care centers, in-patient suites, triage centers and hospital testing equipment relative to the medical diagnostic instruments will minimize risks of EMI exposure.
To reduce the degradation of the MRI imaging resolution, prudent separation distance from busway/conduit risers, switchgears, transformer vaults, adjacent MRIs/NMRs, elevators, loading docks, trains or subways and more is highly suggested for long-term successful imaging quality and sensitive tool integrity.