Structural characteristics analysis of extra–high–head pump–turbine-unit under extreme-pressure working-conditionsXiaoying Huang, Xingxing Huang, Yanqing Huang, Huili Bi, Buchao Xu and Zhengwei WangE3S Web Conf., 561 (2024) 02028DOI: https://doi.org/10.1051/e3sconf/202456102028