Optimal Design of a Micro Reversible Pump Turbine for Balancing Generation Mode and Storage Mode

Abstract

The inefficiency of traditional micro horizontal pump units (double-suction centrifugal pumps) when operating in reverse mode as water turbines has hindered their application in pumped storage systems. In response, this study proposes an optimization approach integrating Bezier curve control, bidirectional weighting, and genetic algorithms (GA) based on computational fluid dynamics (CFD) to enhance the reversible high-efficiency performance of double-suction centrifugal pumps. Bezier curve control is employed to regulate the blade meridional line, enabling the construction of a weighted objective function tailored for two modes. Subsequently, optimal parameter combinations are sought through GA optimization. Additionally, this research presents design considerations for the suction/pressurization chamber and volute to reduce the influence of secondary factors on unit efficiency. The resulting reversible pump-turbine, based on the optimized blade parameters, not only maintains high efficiency in storage mode but also achieves comparable efficiency levels in generation mode. Model testing and simulation analysis of internal flow dynamics validate the efficacy and feasibility of the proposed optimization strategy, facilitating the integration of pump-turbines into pumped storage systems.