Development of a stand for researching electric drives of pumping units
In the modern oil industry, the vast majority of oil production units are represented by sucker rod pumping units, driven mainly by asynchronous electric motors without using any monitoring, control and regulation means. Studies carried out on such installations show their low energy efficiency and reliability. Therefore, the issue of developing complex electric drives of a new generation based on the use of synchronous valve electric motors is relevant allowing to significantly increase the energy efficiency and reliability of both individual installations and to ensure the creation of "smart" oil field control systems. The paper discusses new technical solutions of the experimental stand which makes it possible to study the energy characteristics of electric drives based on asynchronous and synchronous valve electric motors, as well as allowing to create conditions as close as possible to real field conditions with imitation of the operation of an oil pumping unit of a sucker rod pumping unit. In modern test equipment systems, devices are often used to create a mechanical load on the shaft of the electric motor under study. The system proposed and implemented as such a device is "a frequency converter - load asynchronous electric motor", which has been tested on a stand and has proven to be the best in comparison with traditional circuits using DC motors. But using of a load asynchronous electric motor as part of the test stand has revealed a number of disadvantages: overheating of the electric motor operating in the opposing mode, low accuracy of creating the load torque and the speed of the system's response. The problem of overheating of the load electric motor has been solved by transferring the frequency converter to the direct torque control mode, while a significant decrease in the motor current and stabilization of the temperature regime have been detected. The low accuracy and response speed of the system have been increased by introducing feedback and a PID controller into the stand control system.