| 摘要 |
PURPOSE:To improve a thermal efficiency by a method wherein a maximum vacuum (limit pressure) allowable in a performance of condenser type steam turbine is calculated by its operating time in response to its actual operating condition and the pressure in a condenser is automatically adjusted when the turbine is operated under a pressure less than the limit pressure. CONSTITUTION:A turbine is provided with a pressure sensor 1 for use in sensing a differential pressure in the midway of the turbine, the discharged volume of turbine is calculated in a calculater 2 in response to its output and then a limit discharging pressure Pc is calculated. A discharged valcuum sensor 3 is connected to the discharged pressure of the turbine, the actual discharged pressure P2 calculated at the sensor is sent to a comparator 4 along with said limit pressure Pc and then both of them are compared. In case of P2<Pc, a signal for adjusting a volume of cooling water in the condenser is produced in such a way as a relation of P2=Pc is applied and then an angle of pump vane of circulation pump is controlled through the control device 5 in response to the signal. With this arrangement, it is made possible to get the most appropriate discharged vacuum in correspondense with the turbine load or a variation of temperature of cooling water. |
