Q229 : Verifying the Voltage Drop Across a VOLTAGE Energization
Question How can I check that the voltage drop across a VOLTAGE source in HIFREQ is indeed what I specified?
Answer The VOLTAGE energization in HIFREQ imposes a user-specified voltage difference across the mid-points of the first and second part of the energized conductors. The voltage difference consists of three parts:
1. The metal GPR difference:
2. The voltage drop due to losses in the conductor: This can be obtained by multiplying the internal impedance of the conductor by its length and by the current flowing in it. All of these quantities can be read from the table listing the currents in the program's output (F09) file. This often gives a very small contribution.
3. The voltage drop due to the external impedance of the conductor. This is often overlooked. To obtain the value of this term explicitly, request the computation of the vector potential, using a profile that is aligned with the energized conductor. The voltage drop is the product of the component of the vector potential parallel to the conductor and the distance separating the points (strictly speaking, the path integral of the vector potential between the two points).
When everything is added together, taking due care of the phases, the voltage difference that was specified on input should emerge.