Abstract : This paper introduces the structure, working principle, and technical characteristics of a medium-voltage frequency converter-controlled electric submersible pump lifting system. Field application shows that the medium-voltage frequency converter-controlled electric submersible pump lifting technology successfully solves the problem of balanced operation of electric submersible pumps in deep wells of heavy oil in the Tarim Oilfield, providing a good technical solution for the development of deep heavy oil wells in the Tarim Oilfield. Keywords : Heavy oil; Electric submersible pump; Control; Tarim Oilfield The Tarim Oilfield in Xinjiang is a major oil and gas production base of Sinopec in western China. It is characterized by deep reservoir burial (around 5700m), high well production (150-500t/d), high crude oil density (0.95-1.05kg/L), and high viscosity (3000mPa·S), which brings considerable challenges to heavy oil lifting. This oilfield uses electric submersible pumps (EMPs) to lift crude oil. However, the conventional power frequency control system for controlling the EMPs results in a large inrush current during startup, making it impossible to operate the EMPs at different speeds. In deep wells with heavy oil, this often leads to overload shutdowns due to the heavy load. To address these technical issues, the Tarim Oilfield utilizes medium-voltage frequency converters (NVCs) to control the EMP units. By using AC motor frequency conversion speed regulation technology to control the power supply voltage and frequency of the AC motor stator, the motor speed is smoothly changed. Zero-speed soft start protects downhole units, cables, and other electrical equipment. Variable frequency motor speed adjustment enables intelligent control, allowing for pump displacement adjustment. This meets both the needs of formation fluid supply changes and production requirements, ensuring the normal operation of the oil production system and improving the operating efficiency of the EMP system. The medium-voltage frequency converter-controlled EMP units successfully solve the operational problems of EMPs in heavy oil wells, providing strong support for the selection of pumps for heavy oil wells in the Tarim Oilfield. [b]1 Structure and Working Principle 1.1 Structure[/b] The medium-voltage frequency converter controlled electric submersible pump lifting system consists of a medium-voltage frequency converter, a downhole electric submersible pump unit, cables, etc. [b][align=center]For details, please click: Application of Medium-Voltage Frequency Converter Controlled Electric Submersible Pump in Heavy Oil Deep Wells of Tarim Oilfield[/align][/b]