초록 ▼

An adaptive control system for controlling the temperature of desuperheated steam in a turbine bypass system. In one embodiment of the invention, redundant temperature sensors downstream of desuperheating water sprays provide an indication of the actual steam temperature after desuperheating has occ

An adaptive control system for controlling the temperature of desuperheated steam in a turbine bypass system. In one embodiment of the invention, redundant temperature sensors downstream of desuperheating water sprays provide an indication of the actual steam temperature after desuperheating has occurred. The highest value of temperature is automatically selected for control and to provide an error signal to a controller. The controller output, indicative of the deviation from a desired temperature, is multiplied by a factor proportional to steam flow in the bypass system. The multiplied signal is then utilized to proportionally position one or more water control valves to spray more or less water into the bypassed steam. The control system thus automatically adapts itself to variations in steam flow. Preferably, the steam flow is taken as the product of the position of a steam flow throttling valve in the bypass line and the steam supply pressure ahead of the valve. Additionally, operating parameters such as temperature and differential pressures are monitored and continuously compared against limiting values to provide automatic protection action if any of the conditions being monitored warrant such action.

대표청구항 ▼

CM,1. In combination with a steam turbine having a bypass system for diverting excess steam supplied by a steam generator from the turbine and including means for desuperheating the bypassed steam and at least one steam flow control valve, a steam desuperheater control system for controlling the tem

CM,1. In combination with a steam turbine having a bypass system for diverting excess steam supplied by a steam generator from the turbine and including means for desuperheating the bypassed steam and at least one steam flow control valve, a steam desuperheater control system for controlling the temperature of desuperheated steam, comprising: temperature determining means providing a representation of the temperature of the desuperheated steam; first control means operatively connected to said desuperheating means and responsive to said temperature representation to provide corrective action to said desuperheating means tending to maintain the temperature of the desuperheated steam at a preselected temperature reference value; steam flow determining means providing a representation of steam flow rate in said bypass subsystem; and second control means responsive to said steam flow representation and interactive with said first control means to alter said corrective action as a function of steam flow rate in said bypass subsystem.