Steam Turbine Flow Control via Parallel Valve Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steam turbine control systems face challenges in managing high pressure differences with high structural effort and significant flow losses, particularly due to the limitations of rotary slide valves which require high actuation forces and result in inefficient steam flow regulation.
Innovation Solution
A device comprising a rotary slide and a control valve arranged parallel to each other, with a control device that determines pressure differences to selectively activate either the rotary slide or the control valve based on pressure conditions, minimizing actuation forces and flow losses by switching between control methods depending on pressure differences.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a rotary slide is used to control steam mass flow, then flow losses are reduced due to more favorable flow conditions, but high actuating forces are required due to high steam pressure
Solution Approach 1:
The control system is segmented into two parallel valves: a control valve for high-pressure differential conditions and a rotary slide for low-pressure differential conditions. This segmentation allows each component to operate in its optimal pressure range, reducing flow losses when using the rotary slide while avoiding excessive actuating forces by using the control valve when pressure differential is high.
Solution Approach 2:
The system dynamically switches between the control valve and rotary slide based on the pressure differential across the steam turbine. The control device activates the appropriate valve type depending on real-time pressure conditions, optimizing both flow efficiency and actuating force requirements.
2Ease of operation
If a control valve device is used to regulate steam mass flow, then steam parameters can be controlled, but high structural effort is required
Solution Approach 1:
The invention merges the advantages of two different valve types into a single control system. The control valve provides precise control capability for high pressure differentials, while the rotary slide provides efficient flow control for low pressure differentials. Both valves are arranged parallel and can be activated selectively, combining their benefits while managing structural complexity.
Solution Approach 2:
The dual-valve system serves multiple functions: the control valve handles high-pressure differential conditions requiring precise control, while the rotary slide handles low-pressure differential conditions requiring minimal flow losses. This multi-functionality allows a single system to address various operating conditions efficiently.
3Volume of moving object
If a rotary slide is used for steam flow control, then space can be saved by arranging it around the rotor, but high driving forces are required due to sliding without lubrication
Solution Approach 1:
The system segments the flow control function between two parallel valves, allowing the rotary slide to be used only when pressure differential is low. This segmentation enables space-efficient rotary slide design around the rotor while avoiding the high driving forces that would be required for continuous operation under high pressure differential.
Solution Approach 2:
The system changes the operating parameters (pressure differential) to determine which valve type is activated. By monitoring pressure differential and switching between valve types, the system optimizes both space utilization and driving force requirements for the rotary slide.
Data Source
Figure 1
Figure 2A~2C
AI summary
The invention relates to a device for controlling a steam mass flow (m) in the case of a steam turbine (2). The device comprises at least one rotary slide (5) and a further control valve (6), which are arranged parallel to each other in a flow path of the steam turbine. The device (1) also comprises at least one control apparatus (7), which determines a pressure difference (Δp) between the pressure before and the pressure after the device (1) and controls the rotary slide (5) and/or the control valve (6) in accordance with the pressure difference (Δp). The invention further relates to a method for controlling a steam mass flow (m) in the case of a steam turbine (2) having such a device (1).