Radiant Heat Exchanger Control in Dual-Mode Air Conditioners
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In air conditioners that perform both warm-air heating and radiation heating, the radiation heat exchanger struggles to maintain a high temperature due to the compressor's operational frequency being controlled based on the temperature difference between indoor and target temperatures, leading to decreased performance.
Innovation Solution
The air conditioner's controller adjusts the compressor frequency differently for warm-air heating and radiation heating operations, delaying the decrease in compressor frequency during radiation heating and increasing it earlier than in warm-air heating to maintain the radiation heat exchanger's temperature, with specific switch values controlling the compressor's operational modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the compressor frequency is controlled based on the temperature difference between indoor and target temperatures during radiation heating operation, then the warm-air heating performance is improved, but the radiation heat exchanger temperature significantly decreases
Solution Approach 1:
The patent applies dynamics by making the compressor frequency control timing different between radiation heating operation and warm-air heating operation. Specifically, the timing for increasing or decreasing compressor frequency is adjusted based on the operation mode, allowing the system to adapt dynamically to different heating requirements and maintain radiation heat exchanger temperature while ensuring heating performance.
Solution Approach 2:
The patent changes the control parameters (timing for frequency adjustment) based on the operation mode. By setting different frequency adjustment timings for radiation heating versus warm-air heating operations, the system optimizes both the radiation heat exchanger temperature maintenance and the overall heating performance.
2Use of energy by moving object
If the compressor frequency is decreased when the temperature difference is small, then the energy consumption is reduced, but the radiation heat exchanger cannot be maintained at a high temperature
Solution Approach 1:
The system dynamically adjusts the compressor frequency control strategy based on the operation mode. During radiation heating operation, the frequency adjustment timing is modified to prevent excessive frequency reduction, thereby maintaining radiation heat exchanger temperature while still managing energy consumption effectively.
Solution Approach 2:
The control parameters for compressor frequency adjustment are changed based on operation mode. By delaying or advancing the timing of frequency increases and decreases during radiation heating operation, the system balances energy consumption with the requirement to maintain high radiation heat exchanger temperature.
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 effectively maintains the radiation heat exchanger at a high temperature, improving comfort by gradually adjusting the blow-out temperature and ensuring efficient heating performance.
Implementation Method 1
a radiation panel (radiation heat exchanger) arranged on the surface of the indoor unit... causes the refrigerant to flow also in the radiation heat exchanger to perform radiation heating
Implementation Method 2
an indoor heat exchanger disposed to oppose to the indoor fan... performs warm-air heating by causing the refrigerant to flow not in the radiation heat exchanger but in the indoor heat exchanger
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In order to maintain the temperature of a radiant heat exchanger at a high temperature during a heating operation in which both warm-air heating and radiant heating are carried out, this air conditioner is provided with a refrigerant circuit having a compressor, an indoor heat exchanger, a radiant heat exchanger, a pressure reduction mechanism, and an outdoor heat exchanger. The indoor heat exchanger is disposed inside an indoor unit in such a manner as to face an indoor fan, and the radiant heat exchanger is disposed on the outer surface of the indoor unit. The air conditioner has a control means for increasing and decreasing the frequency of the compressor on the basis of the temperature difference between an indoor target temperature and the indoor temperature. In addition, the air conditioner is capable of: a warm-air heating operation in which a refrigerant is flushed through the indoor heat exchanger, without flushing the refrigerant through a radiation panel, to carry out warm-air heating; and a radiant heating operation in which the refrigerant is flushed through the indoor heat exchanger to carry out warm-air heating, and the refrigerant is flushed through the radiation panel to carry out radiant heating. The control means is characterized in that, during the warm-air heating operation and the radiant heating operation, the frequency of the compressor is increased or decreased at different times.