Method of controlling the operation of a feedwater system

Object: At the time of pump trip at upstream, to maintain a good operating characteristic without stopping a pump at the downstream. Structure: In the event that one of pumps at the upstream (for example, a condenser pump) is tripped, interlock is activated to forcibly open a circulating valve for a condensation booster pump to partly return the flow rate of discharge to a pump suction part, thus preventing a decrease in suction pressure. In this case, in order to control suction pressure to a suitable level of pressure more than a net suction water head as required, a pressure adjusting meter for the condensation booster pump is provided on a pipe line on the side of suction so that the flow rate of circulation may be changed by the pressure adjusting valve to maintain the suction pressure in constant. (Kawakami, Y.)