Transport refrigeration system and method for controlling the same
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Refrigeration systems in multi-compartment transport vehicles face high power demands during initialization and temperature regulation, leading to inefficiencies and potential cargo spoilage due to the inability to effectively manage cooling capacity and power consumption across separate compartments.
Innovation Solution
A control system that monitors the temperature of an electric machine powering the refrigeration circuits and adjusts the cooling capacity of individual circuits based on setpoint temperatures and thresholds, prioritizing one circuit over the other to reduce power consumption and maintain optimal engine temperatures, while ensuring full capacity is maintained in non-priority compartments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the refrigeration circuits are commanded to cool from initial ambient temperature to setpoint temperatures during initialization, then the cooling performance is improved, but the power consumption increases significantly
Solution Approach 1:
The patent implements dynamic control of refrigeration circuits by continuously monitoring engine temperature and adjusting cooling capacity in real-time. The system transitions between different operating states (full capacity, reduced capacity, shutdown) based on thermal conditions, allowing the refrigeration system to adapt its power consumption dynamically rather than operating at fixed capacity
Solution Approach 2:
The system changes operational parameters of the refrigeration circuits based on engine temperature thresholds. When engine temperature exceeds the first threshold, the controller reduces cooling capacity by adjusting compressor operation or refrigerant flow. When it exceeds the second threshold, the system shuts down the refrigeration circuit entirely, thereby changing the operational state to manage power consumption
2Use of energy by moving object
If the cooling capacity is reduced to manage power consumption, then the power consumption is improved, but the cooling performance deteriorates
Solution Approach 1:
The system dynamically adjusts cooling capacity based on engine temperature conditions rather than maintaining fixed operation. By implementing continuous monitoring and real-time adjustment, the system optimizes the balance between power consumption and cooling performance, reducing capacity only when thermally necessary
Solution Approach 2:
The controller modifies operational parameters of the refrigeration circuit (such as compressor speed, refrigerant flow rate, or on/off timing) in response to engine temperature thresholds, thereby changing the cooling capacity parameter to match system thermal conditions
3Temperature
If the refrigeration circuit is shut down to prevent engine overheating, then the engine temperature is improved, but the cargo temperature control reliability deteriorates
Solution Approach 1:
The system implements dynamic threshold-based control where refrigeration circuit shutdown is not arbitrary but triggered only when engine temperature exceeds the second threshold. This dynamic response ensures the system maintains cargo temperature control reliability by keeping the refrigeration circuit operational within safe thermal margins
Solution Approach 2:
The system changes the operational state of the refrigeration circuit (from full capacity to shutdown) based on engine temperature parameters. By using threshold-based parameter changes, the system maintains reliability by only shutting down when absolutely necessary for engine protection
Data Source
Figure 1~3
Figure 2
Figure 4
AI summary
An example transport refrigeration system includes first and second refrigeration circuits configured to cool first and second transport compartments, respectively. An electric machine powers the first and second refrigeration circuits. A controller is configured to monitor a temperature of the electric machine, and reduce a cooling capacity of a selected one of the first and second refrigeration circuits based on the temperature exceeding a first threshold.