Novel OTSG secondary loop water feed device

Abstract

The invention provides a novel OTSG (once through steam generator) secondary loop water feed device which comprises a feed valve, a steam feed pump, and a steam inlet valve connected with the steam feed pump, wherein a throttle valve is added between the feed valve and the steam feed pump; a first pressure difference adjuster is mounted on the feed valve in parallel; a second pressure difference adjuster is mounted on the throttle valve in parallel; the first pressure difference adjuster is connected with the throttle valve through a first transmission device; the second pressure difference adjuster is connected with the steam inlet valve through a second transmission device. According to the invention, the throttle valve is added in the loop, so that the feed valve, the throttle valve and the steam feed pump are combined for action; the pressure difference adjusters are added in the system, and pressure drop changes of valves in the system are fed back in real time, so that opening degrees of the valves are changed all the time until the pressure drop values reach the set value. Therefore, during change of the opening degree of the feed valve for each time, after a period of adjustment, the pressure drop of the feed valve is constant, the feed valve operates on an intrinsic flow curve, and the requirement that the feedwater flow forms a linear relation with the opening degree of the feed valve is met.

Description

technical field [0001] The invention belongs to the technical field of water supply for a secondary circuit of a direct-flow steam generator, and in particular relates to a novel water supply device for a secondary circuit of a direct-current steam generator. Background technique [0002] In marine nuclear power plants, the feed water of the once-through steam generator (OTSG) is usually controlled by a feed water valve. Since there are various resistances in the pipeline, such as fluid friction resistance, local resistance, etc., and the size of these resistances will change with the change of flow rate, the pressure drop at both ends of the valve is in the process of constant change. This will make the actual flow curve of the valve deviate from its inherent flow curve, that is, there is an unclear relationship between the flow in the system and the opening of the feedwater valve, and it is difficult to adjust the flow accurately. This brings certain difficulties to contr...

AI Technical Summary

Problems solved by technology

This will make the actual flow curve of the valve deviate from its inherent flow curve, that is, there is an unclear relationship between the flow in the system and the opening of the feedwater valve, and it is difficult to accurately adjust the flow

This brings certain difficulties to control the water flow of the secondary circuit in the actual engineering

Images