This research deals with the effect of capacitive and inductive
harmonics on the efficiency of electrical and electronic devices used in
installing a giant screen owned by Faden Spectrum Company that was
installed on one of the huge towers in the city of Al-Khobar in the
Kingdom of Saudi Arabia, with an area of 2000 m, and
it consists of 2000 cabinets containing 2000 electrical cells, each cell
having an area of 1 m.
The problem was solved -Significantly - by linear grounding, that
provided creative also solutions for four similar screens of relatively
smaller size, which may allow this type of grounding to be generalized
to all electrical networks with similar problems.
The engineering team, under our supervision, worked to reduce the
annoying noise coming from the main feed box (MDB), which was increasing
steadily with increasing lighting intensity, to become 90 dB at 60%
brightness and 155 dB at 100% brightness, by building an independent
linear grounding.
It deals to grounding the zero point of the transformer and this applies
to the screen feeding system as a whole, provided that the old grounding
remains as grounding against touch currents to protect individuals from
electrification.
Our engineers succeeded in reducing the noise caused by harmonics from
95dB to 55dB at 50% brightness (which is the normal operating rate for
this type of screen at noon).
The apparent amperage on neutral has also been reduced to 438A instead
of 811A at the same brightness rate.
This solution is reduced the size of the Active Harmonic Filter to less
than half, saving a lot of money when the customer wants to reach
typical values by used the THD Filtering.