Power Turbine Control Valve Load Sharing via Steam Governor
Solution Overview
Problem
Existing electricity generation systems face inefficiencies and stability issues due to the need for governors in both steam and power turbines, leading to complications in control and increased facility costs, particularly when handling variations in electricity demand and steam turbine output.
Innovation Solution
The system employs a turbine control section that controls the power turbine control valve based on the opening degree of the steam turbine speed governing valve, allowing for load sharing and optimal energy efficiency without a governor for the power turbine, using a control method that adjusts the power turbine control valve based on the steam turbine's target output and load capacity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a governor is provided for both steam turbine and power turbine to enable independent load sharing control, then load sharing control precision is improved, but device complexity and facility costs increase
Solution Approach 1:
The invention extracts the governor function from the power turbine control system, removing the need for a separate power turbine governor while maintaining load sharing control capability through the steam turbine governor's extended functionality
Solution Approach 2:
The steam turbine governor is designed to perform multiple functions: controlling steam turbine output and simultaneously controlling power turbine output through coordinated valve operation, eliminating the need for a separate power turbine governor
2Productivity
If steam turbine output is increased to meet electricity demand when power turbine output or induction steam flow rate increases, then electricity demand is satisfied, but dumped steam is generated and exhaust heat utilization efficiency decreases
Solution Approach 1:
The control system continuously monitors the opening degree of the steam turbine speed governing valve and uses this feedback to calculate and adjust the power turbine control valve opening degree, enabling dynamic load sharing that prevents steam dumping
Solution Approach 2:
The system dynamically adjusts the power turbine control valve opening degree based on real-time steam turbine governor valve position, enabling flexible load distribution between steam and power turbines to match electricity demand without generating dumped steam
3Reliability
If the governor control range is limited by safety constraints to prevent overspeed, then safety is improved, but the ability to respond to large load changes is reduced
Solution Approach 1:
The power turbine control valve acts as an intermediary mechanism that absorbs large load changes, allowing the steam turbine governor to operate within its safe control range while still responding to significant electricity demand variations through coordinated control
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables simpler and more efficient load sharing control, preventing output decreases and dumped steam generation, while maintaining stability and reducing facility costs by eliminating the need for a power turbine governor, thus ensuring effective utilization of exhaust heat for efficient power generation.
Implementation Method 1
a power turbine (7) to be driven by exhaust gas generated in a main engine (3)
Implementation Method 2
a steam turbine (9) to be driven by steam generated by the exhaust gas from the main engine (3)
Implementation Method 3
a power turbine control valve (33) that controls an amount of the exhaust gas to be introduced to the power turbine (7)
Implementation Method 4
a steam turbine speed governing valve (37) that adjusts an amount of steam to be supplied to the steam turbine (9)
Data Source
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AI summary
An electricity generation system and an electricity generation system control method that enables achievement of an optimum energy efficiency via load sharing control without provision of a governor for a power turbine are provided. In an electricity generation system (100) including a power turbine (7), a steam turbine (9), a power turbine control valve (33), a steam turbine speed governing valve (37), a load sharing control section (53) that sets a target output for the steam turbine (9) and a turbine control section (57) including a governor (59) that performs governor control of the steam turbine speed governing valve (37) based on the target output of the steam turbine (9), the turbine control section (57) calculates a target output for the power turbine (7) based on the target output and a load capacity of the steam turbine (9), and when an electricity demand varies, a speed of operation of the power turbine control valve (33) is multiplied by a gain set based on a deviation of an actual output of the power turbine (7) from the target output of the power turbine (7).