The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1996
Filed:
Nov. 04, 1994
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A forced once-through steam generator with an evaporator heating surface has a control device for a furnace which is controlled by a setpoint value L assigned to the steam generator power and a control device for a feed-water mass flow M into the evaporator heating surface. In order to avoid an overshoot of a specific enthalpy at an outlet of the evaporator heating surface, a device is superimposed on the feedwater control device which serves to derive a variable Q(L1)/,[h.sub.sA (L2)-h.sub.iE) as a setpoint value M.sub.s for the feed-water mass flow. In this case h.sub.iE is the specific enthalpy at an inlet of the evaporator heating surface, Q(L1) is a value derived by a first power value L1 from a function generator for a heat flow into the evaporator heating surface and h.sub.sA (L2) is a setpoint value derived by a second power value L2 from the function generator for the specific enthalpy at the outlet of the evaporator heating surface. L1 is a first power value which is delayed with respect to the setpoint value L assigned to the steam generator power, and L2 is a second power value which is delayed with respect to the first power value L1.