Realization Of Variable Frequency Control Technique For Submersible Progressing Cavity Pump Based On DSP

With the development of oil field, the Electric Submersible Progressing Cavity Pump (ESPCP) technique is being applied gradually to meet the requirement of oil exploit. However,the large starting torque and the short using life are the disadvantages in use. Recently the fast development in Variable Frequency Technique and Control Theory makes ESPCP more high-efficient.The thesis begins with the analysis on work characteristics of ESPCP and the disadvantages in use. Various AC Variable Frequency control methods are compared with each other. Combined with characteristics and circumstance of ESPCP, the method of constant V/F control is selected. The DSP, TMS320LF2407 special for motor control is adopted as the controller. The software of Variable Frequency Control for ESPCP is designed and developed with C program language based on the platform of Code Composer Studio 3.1(CCS3.1). The system realizes soft-start, variable frequency speed regulation, real time protect of submersible motor, man-machine operation interface. Therefore, the damage of direct start is avoided, the system is monitored and controlled, the using life is prolonged, and the electric energy is saved. Based on these, the thesis discusses with optimization of control of system. Intelligent control is realized with fuzzy control. And outlet flow is adopted as the controlled variable. The speed of motor is regulated according to the circumstance. The system can prevent the occurrence of pump off and attain the balance between the supply and exploit of crude oil.The field test of the system has been implemented. The result proves that the performance of the system is good and the system meets the requirements.