Two-Stage Heat Pump Load Distribution for Heating Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-stage compression refrigeration cycles with a fixed capacity ratio, the energy consumption efficiency is not satisfactorily maintained due to the fixed capacity ratio of compressors, which restricts the independent control of low-stage and high-stage compressors, affecting the temperature and flow rate ratios for heating water.
Innovation Solution
A heat pump system with a load distribution element and a controller that regulates the temperature and flow rate of refrigerant between the low-stage and high-stage compressors to maintain predetermined conditions or reduce temperature differences, improving energy consumption efficiency by optimizing the COP and APE.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a fixed capacity ratio relationship is used between high-stage and low-stage compression mechanisms, then the device complexity is reduced and manufacturing is simplified, but the energy consumption efficiency deteriorates due to inability to independently control compressor capacities
Solution Approach 1:
The invention introduces a capacity control mechanism that enables dynamic adjustment of the low-stage compressor capacity while maintaining the fixed mechanical coupling. The capacity control mechanism allows the low-stage compressor capacity to be varied independently, transforming a static fixed-ratio system into a dynamically adjustable system that can optimize energy efficiency while preserving the simplified mechanical structure.
2Use of energy by moving object
If the low-stage compressor capacity is reduced to improve energy efficiency, then the temperature difference between discharged refrigerants is reduced, but the heating capacity for hot-water supply deteriorates
Solution Approach 1:
The invention implements a feedback control system that continuously monitors the temperatures of discharged refrigerants from both compressors and dynamically adjusts the low-stage compressor capacity accordingly. The controller receives temperature information and adjusts the capacity control mechanism to maintain optimal temperature matching, ensuring both energy efficiency and adequate heating capacity are achieved through real-time adjustments.
3Ease of manufacture
If the capacity ratio is fixed, then the mechanical structure is simplified with shared drive shafts, but the adaptability to different operating conditions deteriorates
Solution Approach 1:
The invention introduces dynamic capacity adjustment capability into the fixed mechanical structure. The capacity control mechanism allows the system to adapt to different operating conditions by varying the low-stage compressor capacity while maintaining the simplified fixed-ratio mechanical coupling, thus achieving both ease of manufacture and operational adaptability.
4Productivity
If water flow rate to low-stage heat exchanger is increased to improve heating capacity, then the flow speed decreases causing corrosion damage, but energy efficiency deteriorates due to suboptimal temperature matching
Solution Approach 1:
The invention changes the operational parameters by dynamically adjusting the low-stage compressor capacity to optimize the temperature of discharged refrigerant. This parameter adjustment enables the system to achieve adequate heating capacity through improved temperature matching rather than increasing water flow rate, thus maintaining higher flow speeds that prevent corrosion while avoiding suboptimal thermal conditions.
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
The system enhances energy consumption efficiency by maintaining or adjusting temperature ratios and flow rates, reducing energy consumption while preventing damage to heat exchangers from low fluid flow speeds, thus improving overall performance and reducing corrosion risks.
Implementation Method 1
a compression mechanism (20) having a low-stage compression mechanism (22) and a high-stage compression mechanism (26) with a fixed capacity ratio relationship
Implementation Method 2
one flow of hot water is heated by the refrigerant discharged from the high-stage compressor, and the other flow of hot water is heated by the refrigerant discharged from the low-stage compressor
Data Source
AI summary
A heat pump system includes a heat pump circuit, a load distribution element, and a controller. The heat pump circuit includes low-stage and high-stage compression mechanisms having a fixed capacity ratio relationship. The load distribution element establishes a load distribution between first and second heat loads subjected to heating processes by heat exchange with refrigerant discharged from the low-stage and high-stage compression mechanisms, respectively. The controller performs distribution control to maintain a ratio of 1 between temperatures of the refrigerant discharged from the low-stage and high stage compression mechanisms and after heat exchange with the first and second heat loads, respectively. Alternatively, the controller performs distribution control to reduce a difference between the temperatures of the refrigerant discharged from the low-stage and high stage compression mechanisms and after heat exchange with the first and second heat loads, respectively.