| 摘要 |
PROBLEM TO BE SOLVED: To stabilize the pressure control by detecting the intake side pressure and the discharge side pressure by pressure sensors, respectively, integrating the fluctuation of both the pressures to control conditions to perform a precise control along a conduit resistance curve for performing a terminal pressure constant control. SOLUTION: The deadend pressure Ha in zero water quantity, the pressure Hb in maximum water quantity, the pump reference speed NMAX, and the deadend pressure Hc in the operation at this speed, which are desired by a water feed system, are set on the basis of a predetermined pipe line resistance curved of a water feed pipe line. The operation speed satisfying the deadend pressure Ha in zero water quantity and the speed satisfying the pressure Hb in maximum water quantity are determined on the basis of the pressure detected by an intake side pressure sensor, and a target pressure is determined from these speeds. When the actual pressure reaches a target pressure before the target pressure is renewed, the following target pressure is determined from the present operating speed. Accordingly, even if the pressure of a feed pipe is fluctuated, a terminal pressure constant control method can be realized only with the pressure sensor without using a flow sensor. |
