球阀动水关闭过程中球阀与机组稳定性分析

摘要

Based on measured data from one pumped storage power station,stability parameters of pumped storage unit and ball valve have been analyzed by short time Fourier transform.Frequency changes of the ball valve and unit during ball valve closing in dynamic water conditions have been summarized.The research shows that the unit and ball valve vibrations involve a 100 Hz component in stable running condition.And the 100 Hz component mainly results from two-fold blade passing frequency not from generator polar frequency;the two-fold blade passing frequency component propagates upward and aggravates the vibrations of unit and ball valve.%采用短时傅里叶变换方法,针对某抽水蓄能电站水泵水轮发电机组球阀动水关闭过程中机组及球阀的试验数据进行了分析,研究了球阀动水关闭前、后及过程中机组及球阀的主要频率成分变化情况.研究结果表明:稳态工况下球阀及机组存在明显的100 Hz频率成分,该频率成分主要由两倍的叶片通过频率产生而非电机极频振动产生;两倍叶片过流频率具有向上传播的特性,加剧了机组与球阀的振动.