Improving Stability by Misaligned Guide Ganes in Pumped Storage Plant

Misaligned guide vanes(MGVs) can improve the stability of the reversible pump turbines in no-load mode and turbine startup mode and cut down the surge pressure rises under turbine load-rejections. In order to achieve a more widely application of MGVs in high-head pumped storage plants, the internal characteristics of the reversible pump turbine with MGVs in turbine modes and reversed pump modes, the empirical formulae at runaway and zero-flow special condition point were proposed. The equivalent opening of guide vanes was defined for the interpolation of the new characteristic curves with MGVs from the original model characteristic curves. Finally, the investigations by the site tested results in Tianhuangping pumped storage plant confirm the presented theories and its engineering practice.