Vehicle Chiller Superheat Control Without Compressor Shutdown
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional vehicular heat management systems unconditionally turn off the compressor when the refrigerant superheat degree on the discharge side of the chiller is less than or equal to a lower limit value, leading to frequent compressor turn-offs, chiller operation stops, and battery overheating.
Innovation Solution
A vehicular heat management system that includes a control part to sequentially control the compressor and the electromagnetic expansion valve to increase the refrigerant superheat degree step-by-step when it falls to a lower limit value, thereby avoiding unconditional compressor shutdown.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the compressor is turned off when the refrigerant superheat degree is less than or equal to a lower limit value, then the compressor is protected from damage due to high liquid phase ratio refrigerant, but the chiller operation stops and the battery overheats
Solution Approach 1:
The system dynamically adjusts the compressor operation mode based on real-time superheat degree measurements. When superheat is low, the compressor operates in a reduced capacity mode rather than shutting off completely, allowing continuous but limited refrigerant flow to maintain battery cooling while preventing liquid refrigerant damage
Solution Approach 2:
The control system changes the compressor operating parameters (rotation speed, capacity) based on the superheat degree. By adjusting these parameters dynamically, the system maintains compressor protection while ensuring continuous cooling operation for the battery
2Reliability
If the compressor is turned off when the refrigerant superheat degree is low, then the refrigerant superheat degree increases, but the chiller operation stops and cooling performance is lost
Solution Approach 1:
The chiller operates dynamically with variable refrigerant flow based on superheat degree. The system modulates compressor capacity to maintain appropriate superheat while ensuring continuous refrigerant circulation through the chiller, preserving cooling performance
Solution Approach 2:
The cooling function of the chiller is maintained continuously by keeping the compressor running. The system ensures uninterrupted refrigerant flow and heat exchange, maintaining productivity while controlling superheat degree
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 solution minimizes compressor turn-offs, reduces chiller operation stops, prevents battery overheating, and extends compressor durability by maintaining the refrigerant superheat degree above the lower limit value.
Implementation Method 1
the battery-cooling expansion valve 20a is an electromagnetic expansion valve EXV
Implementation Method 2
a condensing heat exchanger 16
Implementation Method 3
an evaporation heat exchanger 18
Implementation Method 4
the generated cold air is transferred to the battery B through a cooling water circulation line 22, thereby cooling the battery B
Implementation Method 5
a compressor 14
Data Source
AI summary
The present invention relates to a vehicular heat management system capable of inducing an increase in refrigerant superheat degree without unconditionally turning off a compressor when the refrigerant superheat degree on the discharge side of a chiller is less than or equal to a lower limit value.The vehicular heat management system includes: a compressor; a condensing heat exchanger; an expansion valve; an evaporation heat exchanger; and a control part configured to, when a refrigerant superheat degree on a discharge side of the evaporation heat exchanger is lowered to a predetermined lower limit value or less, control, step by step, at least two devices directly involved in the increase and decrease of the refrigerant superheat degree to increase the refrigerant superheat degree until the refrigerant superheat degree exceeds the lower limit value.