Supercritical CO2 Cascade Cycle Layout for Direct-Drive Power Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing supercritical CO2 generation systems experience power loss and reduced efficiency due to the need for additional components and processes to convert turbine output to suitable RPM and frequency for power generation, leading to increased costs and complexity.
Innovation Solution
A supercritical CO2 generation system employing a parallel expansion type cascade cycle with multiple heat exchangers and turbines, where the working fluid is divided into multiple flows to optimize heat exchange and power generation, reducing the need for torque converters and gearboxes, and utilizing a cooler to recycle waste heat, thereby improving efficiency and reducing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a turbine with high RPM is used to match cycle characteristics, then power generation efficiency is improved, but additional components (torque converter, gearbox, inverter) are required which increase system complexity and cost
Solution Approach 1:
The patent replaces the mechanical transmission system (torque converter, gearbox) with a direct-drive configuration where the turbine is directly coupled to the generator. This eliminates the need for mechanical conversion components while maintaining optimal RPM matching between turbine and generator, thereby improving efficiency and reducing system complexity.
Solution Approach 2:
The turbine is designed to serve dual functions: directly driving the generator for power production and simultaneously compressing the working fluid through its rotational motion. This multi-functionality eliminates the need for separate compression equipment and transmission components, reducing overall system complexity while maintaining high power generation efficiency.
2Adaptability or versatility
If torque converter and gearbox are added to convert RPM, then turbine output can be matched to generator requirements, but power loss occurs and costs increase
Solution Approach 1:
The patent eliminates mechanical transmission components (torque converter, gearbox) that cause energy loss through friction and conversion inefficiencies. Instead, it uses a direct-drive configuration where the turbine rotor is directly coupled to the generator, maintaining optimal RPM matching without energy loss. The turbine's rotational energy is directly transferred to the generator, preserving maximum power output.
3Reliability
If frequency converter is used to convert power frequency, then constant output frequency is achieved, but additional parts and processes increase cost
Solution Approach 1:
The patent replaces the electrical frequency conversion system (inverter) with a direct mechanical coupling between turbine and generator. The turbine's rotational speed directly determines the generator's output frequency, eliminating the need for complex electrical conversion equipment. This mechanical-direct approach achieves constant output frequency while significantly reducing system complexity and component count.
Data Source
AI summary
A supercritical CO2 generation system including a compressor configured to compress a working fluid; a first heat exchanger that exchanges heat with the working fluid passing through the compressor; a high temperature turbine that expands the working fluid passing through the first heat exchanger and connects to a power generator to produce power; a second heat exchanger that exchanges heat with the working fluid passing through the compressor; a low temperature turbine that expand the working fluid passing through the second heat exchanger and connects to the power generator to produce power; a third heat exchanger between the first heat exchanger and the high temperature turbine that exchanges heat with the working fluid recuperated by the first heat exchanger; and a cooler that cools the working fluid passing through the high temperature turbine and the low temperature turbine and supplies the cooled working fluid to the compressor.