Browse Prior Art Database

Pump Group Control System

IP.com Disclosure Number: IPCOM000104447D
Original Publication Date: 1993-Apr-01
Included in the Prior Art Database: 2005-Mar-19
Document File: 2 page(s) / 67K

Publishing Venue

IBM

Related People

Akizuki, S: AUTHOR [+4]

Abstract

Disclosed is a pump group control system which consists of a variable flow pump and plural fixed flow pumps for high-efficient and stable supply pressure.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 70% of the total text.

Pump Group Control System

      Disclosed is a pump group control system which consists of a
variable flow pump and plural fixed flow pumps for high-efficient and
stable supply pressure.

      In a conventional pump group control system, start/stop
operations are basically controlled by the comparison of the flow
with pump capacity through pump group controller 1 (Figs. 1 and 2).
An additional pump starts when the flow is larger than the preset
value for start.  An excess pump stops when the flow decreases to the
the preset value for stop.  On the other hand, supply pressure is
controlled by a variable flow pump through variable pump controller 3
in compliance with the output signal of pressure controller 2.  If
the flow decreases below the low control limit of the variable flow
pump, supply pressure increases and excess pressurized water is
circulated through two-way-control valve 4 which is a waste of
energy.  Besides, the the pump group control target is treated
independent of pressure control target which causes unstable
pressure.

      Figs. 3-5 show the new control system.  Mechanism of starting
an additional fixed flow pump is as follows:  An additional pump
starts when both the low limit deviation signal 6 from the set point
of pressure and the maximum pump speed signal 7 of pressure
controller 3 occur.  Consequently, an additional pump does not start
until variable flow pump is fully utilized.

      Mechanism of decreasing an excess fixed...