Short bio about DOS Manufactured Products
DOS Manufacturing starting with the 6-pulse VSD with PWM Sine wave filtered output back in 1996. Then
we added the passive input filter to this VSD input and manufactured these for many years with good results
but with limitations.
As newer VSD technology surfaced and as per oil company specifications, we developed the 12-pulse
and 24-pulse VSD and also found limitations with additional drawbacks from the passive filter
approach, such that we now require an additional expense phase shifting transformer and further
finding restrictions on eliminating (mitigating) harmonics due to the unbalance and less then 100%
VSD loading seen at most ESP oilfield.
Since 2013, we incorporated the Active Front End AFE-VSD with a customized harmonics elimination and
power factor compensation input and with 3kHz output customized Sine wave filter. The AFE has the
lowest input harmonic distortion, no matter how loaded and unbalanced, highest power factor, lowest
losses, lowest operating cost, lowest per barrel cost and purest sine-wave input to the power source
and output to the ESP motor.