Control of a forced-flow,once-through boiler

摘要

1,061,848. Fluid-pressure servomotor systems. SIEMENS-SCHUCKERTWERKE A.G. March 15, 1965 (March 13, 1964], No.10947/65. Heading G3P. In a forced-flow once-through steam boiler, a main controller regulates the rate of flow of working medium through the boiler while an auxiliary and more quickly responding control regulates the rate of flow in response to the enthalpy of slightly superheated steam. Signals representing the temperature and pressure of slightly superheated steam is fed to a computer which provides a signal representing the enthalpy of the steam which is supplied to the auxiliary controller. A valve is also arranged to control water infection to the inlet side of the superheater in response to temperature.