Cooling Device Valve Control for Dynamic Refrigerant Flow Optimization
Solution Overview
Problem
Cooling devices, such as refrigerators and air-conditioners, face inefficiencies due to fixed capillary tube sizing, which optimizes performance only at specific working conditions, limiting energy efficiency and operational costs.
Innovation Solution
A method and device that dynamically control the mass flow of refrigerant by using a valve in the fluid path between the condenser and evaporator, allowing for variable flow rates through pulsing or direct control, with pulse ratios adjusted based on ambient temperature, temperature differences, and compressor power to optimize energy efficiency across the compressor cycle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed capillary tube is used for fluid expansion, then the device structure is simple and manufacturing cost is low, but the system can only achieve optimal performance at specific working conditions and cannot adapt to changing ambient temperatures and compressor loads
Solution Approach 1:
The patent applies the dynamics principle by replacing the fixed capillary tube with a dynamic expansion system using an electronically controlled valve that can adjust its opening degree in real-time. The valve receives control signals from a controller that monitors ambient temperature, compressor load, and system pressure, enabling the expansion device to adapt to changing working conditions while maintaining optimal refrigerant flow rates.
Solution Approach 2:
The patent implements parameter changes by varying the opening degree of the expansion valve as a controllable parameter. The controller adjusts the valve opening based on measured system parameters (ambient temperature, compressor frequency, pressure differential) to optimize refrigerant expansion. This allows the system to maintain optimal performance across different operating conditions by dynamically changing the expansion parameter.
2Use of energy by moving object
If a controllable valve is introduced to dynamically adjust refrigerant flow, then energy efficiency is improved across varying operating conditions, but the device complexity and control system requirements increase
Solution Approach 1:
The patent applies feedback control by implementing a closed-loop system where the controller continuously monitors system parameters (ambient temperature via sensor, compressor load via frequency signal, pressure via differential pressure sensor) and adjusts the valve opening degree accordingly. This feedback mechanism ensures optimal energy efficiency by adapting refrigerant flow to actual system needs while providing intelligent control that compensates for the added device complexity.
Solution Approach 2:
The system implements self-service control where the controller automatically adjusts the expansion valve based on sensor inputs without requiring manual intervention. The controller receives signals from the compressor control unit and pressure sensor, processes this information, and autonomously optimizes the refrigerant flow, making the system self-regulating and reducing the operational burden despite increased control system complexity.
3Productivity
If the valve opening is increased to maximize refrigerant flow, then cooling capacity is improved, but the system may operate inefficiently during partial load conditions and increase energy consumption
Solution Approach 1:
The patent applies dynamics by making the valve opening degree a dynamic parameter that changes with system conditions. Rather than maintaining a fixed wide opening to maximize cooling capacity, the valve opening is continuously adjusted based on ambient temperature, compressor load, and pressure differential. This dynamic adjustment ensures the system produces the exact cooling capacity needed at each moment, avoiding energy waste from excessive cooling while maintaining high productivity when required.
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 enhances energy efficiency by maintaining optimal refrigerant flow, reducing energy consumption and operational costs by dynamically adjusting the valve opening to match changing conditions during the compressor cycle.
Implementation Method 1
A valve (18) is provided in the fluid path between the condenser (14) and the expansion device (26). The controller (22) is configured to control the opening of the valve (18) during an on-cycle of the compressor (12)
Implementation Method 2
The cooling device comprises a circuit in which a refrigerant fluid is circulated in a fluid path where the circuit comprises a compressor (12) and a condenser (14) provided down streams the compressor (12)
Implementation Method 3
The compressor (12) has the function of promoting the flow of cooling gas inside this refrigeration system and is capable of causing a pressure difference between the points where the evaporation and the condensation of the cooling gas occur
Implementation Method 4
a condenser (14) provided down streams the compressor (12)
Data Source
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AI summary
Described is, among other things, a method and an apparatus for control of a cooling device. The cooling device comprise a circuit in which a refrigerant fluid is circulated in a fluid path where the circuit comprises a compressor and a condenser provided down streams the compressor. A fluid expansion device is provided down streams the condenser and an evaporator is provided between the fluid expansion device and the compressor. The circuit further comprises a valve provided in the fluid path between the condenser and the fluid expansion device. The method comprises to during an on-cycle of the compressor controlling the valve opening to provide a variable fluid mass flow of the refrigerant fluid circulated in the circuit where the valve opening is controlled to decrease during the on-cycle of the compressor.