(EP913577-A1)      A pump-turbine system having a flow-rate regulator such as a guide vane and more particularly to a pump-turbine system having an inlet valve. By provision of the inlet valve, in the event of an emergency stop in a power generation mode and even when the guide vane is put in an abnormal condition, it is possible to effect a closing operation by the inlet valve, so as to safely stop the operation without causing abnormal water hammer.    In the case of emergency stop in a pumping mode and even when the guide vane is put into an abnormal condition, the inlet valve can prevent a reversing phenomenon and safely stop the operation, while reducing the load to the pump-turbine.    ADVANTAGE -   Reduced risk of hydraulic hammer during emergency shut-down    (JP10506767-X)      A pump-turbine system having a flow-rate regulator such as a guide vane and more particularly to a pump-turbine system having an inlet valve. By provision of the inlet valve, in the event of an emergency stop in a power generation mode and even when the guide vane is put in an abnormal condition, it is possible to effect a closing operation by the inlet valve, so as to safely stop the operation without causing abnormal water hammer.    In the case of emergency stop in a pumping mode and even when the guide vane is put into an abnormal condition, the inlet valve can prevent a reversing phenomenon and safely stop the operation, while reducing the load to the pump-turbine.    ADVANTAGE -   Reduced risk of hydraulic hammer during emergency shut-down    (US6250887-B1)      A pump-turbine system having a flow-rate regulator such as a guide vane and more particularly to a pump-turbine system having an inlet valve. By provision of the inlet valve, in the event of an emergency stop in a power generation mode and even when the guide vane is put in an abnormal condition, it is possible to effect a closing operation by the inlet valve, so as to safely stop the operation without causing abnormal water hammer.    In the case of emergency stop in a pumping mode and even when the guide vane is put into an abnormal condition, the inlet valve can prevent a reversing phenomenon and safely stop the operation, while reducing the load to the pump-turbine.    ADVANTAGE -   Reduced risk of hydraulic hammer during emergency shut-down