Key Structural Design of a Downhole Variable-Angle Hollow-Shaft Turbine Generator
To address the insufficient wide-flow adaptability, limited structural integration, and restricted tool passability of downhole turbine power generation systems, a downhole variable-angle hollow-shaft turbine generator system is proposed. The system consists of a guide vane, a variable-angle turbine, a hypoid gear adjustment mechanism, and a hollow-shaft outer-rotor permanent magnet generator. Based on blade design theory, velocity triangle theory, and isentropic flow theory, the key parameters of the guide vane and turbine are determined, and 14 attack-angle models ranging from 0° to 90° are established. A hypoid gear mechanism is designed to realize synchronous angle adjustment of multiple blades, and a hollow-shaft outer-rotor permanent magnet generator is developed to achieve compact integration of the turbine, transmission mechanism, and power generation unit, providing a reference for the optimization and engineering application of downhole turbine power generation devices.
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