Load features of oil industry
More than 85% electric load of power grid in oil industry are induction load, such as oil pump, motors and so on. In recent years, with the higher requirement for energy saving in oil industry, energy-saving device had been widely used. So frequency converter are more and more widely applied due to its energy-saving effect, easy maintenance and so on. In production station, oil well pump, oil transfer pump and so on are all drag by frequency converter. Unfortunately, converter will produce much harmonic which can disturb loads and effect power grid.
Harmonic effects for oil grid
Harmonic will effect grid stable operation, and reduce the power supply quality;
Harmonic will increase capacitor loss power, shorten the service life of capacitor or even explosion, harmonic will also increase power loss of transformer;
Harmonic will cause the power loss increase of electric rotating machinery,
cause over heating, noise and harmonic over voltage, if much serious, the machinery will be damaged
4. The harmonic maybe couple to weak current system through electro-magnetic induction, electrostatic induction and so on. So the weak current system maybe interferenced.
Typical site reference
With the VFDs being widely used in the oilfield water injection system, the problems concerning big water-injection pressure change, high power consumption, low efficiency have been overcome. On the other hand, considerable harmonics are also created with the widespread applications of VFDs and consequently pose threat to the operation safety and realiability of the power distribution system. In order to eliminate the harmonic effects, the company’s water injection stations has applied Hoteam active power filters as solution. As a result, the normal production is guaranteed with the power quality being greatly improved.
Work result analysis
After Active Harmonic Filter works, voltage and current waveform are improved, harmonic content is highly reduced, THDv is reduced from 2.7% to 0.8%, while THDi is reduced from 43.5% to 4.2%,
After compensation, the power factor is more than 0.95, it shows the ability of harmonic and reactive power comprehensive management
Electric energy loss is reduced, the factory equipment operation environment is more secure.