Battery Chiller Control With Electronic Expansion Valve for Dual Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In vehicle air-conditioning systems, there is a challenge in balancing the thermal management of traction batteries and cabin cooling, as the combined load can exceed the capacity of the refrigerant subsystem, leading to unsatisfactory cabin temperatures when both battery and cabin cooling are required simultaneously.
Innovation Solution
A climate-control system with a refrigerant subsystem and a coolant subsystem, including an electronic expansion valve (EXV) that adjusts refrigerant flow based on measured coolant temperature differences and chiller capacity to optimize thermal energy transfer between the refrigerant and coolant systems, ensuring efficient cooling of both the battery and cabin.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the refrigerant subsystem is used to cool both the traction battery and the cabin simultaneously, then the thermal management of both components is addressed, but the combined cooling load exceeds the subsystem's capacity, resulting in unsatisfactory cabin temperatures
Solution Approach 1:
The electronic expansion valve (EXV) dynamically adjusts refrigerant flow distribution between the battery chiller and cabin evaporator based on real-time temperature sensors and control algorithms. The valve position is continuously modulated to optimize the split of cooling capacity, allowing the system to adapt to varying thermal demands of the battery and cabin throughout operation
Solution Approach 2:
The system changes the refrigerant flow parameters (flow rate, pressure, temperature) by adjusting the EXV opening degree to match the varying cooling demands. The controller modifies these parameters in real-time based on battery temperature, cabin temperature, and ambient conditions to maintain optimal cooling capacity distribution
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 effectively balances battery and cabin cooling demands, preventing overheating and maintaining desired cabin temperatures by dynamically adjusting the EXV position and refrigerant flow, thereby optimizing the thermal management system's capacity.
Implementation Method 1
a chiller arranged to transfer heat between a refrigerant subsystem and a battery-coolant subsystem
Implementation Method 2
a chiller arranged to transfer heat between a refrigerant subsystem and a battery-coolant subsystem
Data Source
AI summary
A climate-control system for a vehicle includes a refrigerant subsystem having a chiller and an electronic expansion valve (EXV) arranged to selectively route refrigerant to the chiller. The vehicle further includes a coolant subsystem having conduit arranged to circulate coolant through a traction battery and the chiller. The coolant subsystem further includes a first temperature sensor configured to measure coolant circulating into an inlet side of the chiller and a second temperature sensor configured to measure coolant circulating out of an outlet side of the chiller. A vehicle controller is configured to, in response to the battery exceeding a threshold temperature and cabin air conditioning being requested, command opening of the EXV to a predetermined position and adjust the position based on a measured coolant temperature difference between the first temperature sensor and the second temperature sensor.