Study On The Intermittent Supply Strategy For The Beam Pumping Motors Based On Energy Flow Analysis

In the pumping units widely used in oil field, the motors operate with periodically changing load, and the intermittent supply energy-saving strategy for this situation was already used in practice. However, because of the confinements of control strategy and processor's performance, the rotor's speed fluctuates in a large scale and the stator's inrush current appears frequently. In order to solve those problems, the paper analyses the energy flow process of the pumping motor system and proposes the improvement measures: through motor's power supervision, the new control strategy is used to reduce rotor speed fluctuation; by using rapid soft switching scheme, the inrush current is restrained to acceptable level. To realize all the strategies, the upgrading of the hardware is required so the last part of the paper introduced the designing of control device based on DSP.