Efficiency of a submersible plunger pump linear motor

Abstract

Modern oil extracting has difficulties with extraction at depths exceeding 2 kilometers from mid and low debit wells. Traditional way for extraction from mid and low debit wells (pumping unit) is unacceptable for this task, because of rod column break hazard. Meanwhile, submersible electrical centrifugal pumps that are usually used for oil extracting from big depth have very low efficiency on low debit wells. Due to that, a new class of oil extraction equipment has appeared—submersible plunger pumps. Their world-leading manufacturer is China. The biggest progress in submersible plunger pump linear drive research was reached in Perm National Research Polytechnic University. Although efficiency of this type of pumps on low debit wells is much higher than centrifugal pumps have, it is still very low and does not exceed 30%. Thus, efficiency improvement of gaining popularity submersible plunger pumps is an important task not only for oil extraction but also for energy saving. Major power loss happens in windings of submersible linear motors. Because of that, first step of pump efficiency improvement is improvement of linear drive efficiency. Motor design optimization allows to significantly raise its efficiency to 50%. Higher efficiency could be reached by optimizing motor operation algorithm and using better materials.