Description

One of the most effective ways to reduce the cost of mechanized oil production is to replace an asynchronous electric motor with a multi-stage reducer of the pumping unit drive with a synchronous electric drive with a reduction in reduction by 2 or more stages. This “upgrade” of the pumping unit provides the following key benefits for the oil company:

• significant reduction in operating costs due to the higher efficiency and reliability of the electric drive, as well as the absence of high starting currents;
• extension of the operating range of regulation of the pump speed and
• reduction of weight, dimensions and cost of installation of the pumping unit.

Experimental solutions for the “upgrade” of pumping units from asynchronous to synchronous electric drives have already begun to appear, however, the synchronous electric motors used for these purposes have too low specific torque (usually less than 4 N·m/kg), which does not fundamentally solve the problem excessive weight and dimensions. Due to the large material consumption, the cost of the electric drive and its installation remains high, and the reduction factor cannot be reduced by more than 2 steps.

Electric drives based on high-torque synchronous modular electric motors iEM-IIL-50 have the ultimate specific power characteristics in their class, surpassing similar synchronous electric motors by 3-4 times and allowing the use of only one- or two-stage gearbox of pumping units! This provides a dramatic increase in the resource and reliability of the system.

Comparison of the rocking machine drives: on the right – a classic asynchronous gear motor with a belt drive and a multi-stage gear; on the left – the iEM-IIL-50 synchronous electric drive with one- or two-stage gearbox.

The modularity of the iEM-IIL-50 allows, if desired, not only to scale the electric drive in terms of power and torque for use in pumping units of various capacities, but also to provide increased reliability and uninterrupted operation of the pump by duplicating electric drives.

Unlike analogs, all synchronous electric motors of the iEM family have the same number of stator and rotor poles, which provides the electric drive with not only high specific power characteristics, but also excellent controllability in the entire operating range of rotations.

The iEM-IIL-50 modules can be controlled by dedicated frequency converters designed for multi-pole synchronous motors.

Unlike the standard version, the improved iEM-IIL-50 modules use special imported materials and components, which do not yet provide full import substitution for customers in the Russian Federation. For the same reason, the cost of electric drives based on iEM-IIL-50 is several times higher than standard drives based on iEM-II-50 modules.

When equipped with an external encoder, an electric drive based on the iEM-IIL-50 turns into a high-torque servo drive for industrial robotic systems.

Key advantages of iEM-IIL-50 synchronous motors over induction motors:

• constant high torque in the entire operating range of rotations (from 0 to nominal);
• 6-8 times less weight and dimensions in comparison with an asynchronous gear motor of the same power provides a high compactness and mobility of the system, and also reduces the cost of installation work;
• Hollow shaft modularity makes it easy to scale electric drives in terms of power and torque;
• overload resistance allows for a short-term development of a torque that is 2-3 times higher than the nominal;
• absence of overcurrents during acceleration of the electric motor;
• good controllability throughout the entire operating range of rotation
• low inertia of the rotor provides high speed in servo mode;
• low operating costs for periodic maintenance and long service intervals.