Refrigerant Mode Switching Based on Multi-Factor Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current air conditioning, heat pump, and refrigeration systems lack an efficient method to dynamically adjust between economized and standard modes based on multiple efficiency factors, leading to suboptimal performance and energy usage.
Innovation Solution
A refrigerant system with a control system that shifts between economized, standard, and bypass modes responsive to compressor isentropic efficiency, condenser efficiency, evaporator efficiency, motor efficiency, and cycling efficiency, utilizing solenoid valves and expansion devices to manage refrigerant flow and optimize operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the system operates in a fixed mode (standard or economized), then the valve structure remains at a fixed position, but the system cannot adapt to varying efficiency conditions and operates suboptimally
Solution Approach 1:
The system dynamically switches between standard mode and economized mode based on real-time efficiency calculations. The control system continuously monitors operating conditions and adjusts the mode of operation, transforming a static fixed-position valve system into a dynamic adaptive system that responds to changing efficiency conditions.
Solution Approach 2:
The control system calculates system efficiency based on multiple factors (compressor isentropic efficiency, condenser efficiency, evaporator efficiency, motor efficiency, and cycling efficiency) and uses this feedback to determine when to switch between modes. This closed-loop feedback mechanism enables the system to adapt to varying efficiency conditions and maintain optimal performance.
2Loss of energy
If the system uses multiple efficiency factors for mode selection, then the energy optimization improves, but the calculation and control complexity increases
Solution Approach 1:
The control system segments the overall efficiency calculation into five distinct components: compressor isentropic efficiency, condenser efficiency, evaporator efficiency, motor efficiency, and mode-associated cycling efficiency. Each component is calculated and monitored separately, allowing the system to comprehensively assess energy performance while maintaining manageable measurement and control complexity through modular evaluation.
3Productivity
If the system dynamically switches between modes, then the compressor efficiency improves, but the cycling frequency and associated losses may increase
Solution Approach 1:
The control system includes a mode-associated cycling efficiency factor that anticipates and accounts for the losses inherent in mode switching. By pre-calculating and incorporating cycling efficiency into the overall efficiency determination, the system can make informed decisions about when to switch modes, balancing the benefits of improved compressor efficiency against the anticipated time losses from cycling.
Data Source
AI summary
A refrigerant system is configured to alternatingly run in an economized mode and a standard mode. A control system shifts the refrigerant system between the economized mode and standard mode responsive to a determined efficiency reflecting a combination of at least two of: compressor isentropic efficiency; condenser efficiency; evaporator efficiency; efficiency of hardware mechanically powering the compressor; and a mode-associated cycling efficiency. In a bypass mode, a bypass refrigerant flow from an intermediate port may return to the suction port. Shifting into the bypass mode may be similarly controlled based upon the determined efficiency.