Multi-Compressor Refrigeration Control for Reliable Restart
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In refrigeration systems with multiple compressors, pressure differences can hinder the restart of stopped compressors, and existing solutions fail to effectively manage the interdependence of compressor operations to prevent these issues.
Innovation Solution
A control system with electronic units connected to each compressor that communicate start/stop signals to control the operation of the compressors in a mutually dependent manner, ensuring that if one compressor stops or starts, the other can be correspondingly controlled to avoid pressure differences and overload.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If one compressor is stopped while others keep running, then the running compressors maintain system operation, but pressure difference builds up between pressure side and suction side making it difficult for the stopped compressor to restart
Solution Approach 1:
The control system continuously monitors the operational state of each compressor and uses this feedback to determine when to start or stop compressors. When one compressor stops, the control system detects this change and sends a signal to stop the other compressors, preventing harmful pressure differences from building up and ensuring reliable restart capability.
Solution Approach 2:
The control system merges the control of multiple compressors into a coordinated operation where their start/stop decisions are interdependent. Instead of independent control, the system combines the operational states of all compressors and manages them as an integrated group, ensuring that when one stops, others also stop to maintain proper pressure balance.
2Reliability
If both compressors are stopped and only one is restarted, then the system resumes operation with one compressor, but it becomes difficult for the remaining compressor to restart later due to pressure differences
Solution Approach 1:
The control system monitors which compressor was restarted first and uses this feedback to prevent the other compressor from being restarted independently. When one compressor restarts after both were stopped, the control system detects this state change and ensures the other compressor remains stopped, avoiding pressure difference issues that would prevent future restarts.
Solution Approach 2:
Before allowing a compressor to restart, the control system preliminarily checks the operational state of other compressors and the system pressure conditions. This preliminary action prevents restart attempts that would create harmful pressure differences, ensuring that compressors are only restarted when system conditions are appropriate.
3Adaptability or versatility
If compressors are controlled individually, then each compressor can operate independently, but problems arise when one stops and others continue running causing pressure differences
Solution Approach 1:
The control system merges the independent control of each compressor into a unified control approach. While compressors can still operate independently in terms of physical separation, their control decisions are combined and coordinated through the control system that monitors all compressors and makes start/stop decisions based on overall system state rather than individual compressor states.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A control system (12) for controlling a refrigeration system (17) comprising two or more compressors (13a, 13b) (e.g. a twin compressor system) . Each compressor (13a, 13b) is connected to an electronic unit (14a, 14b) , and the electronic units (14a, 14b) are adapted to communicate appropriate signals to each other when the corresponding compressor (13a, 13b) starts or stops operation. The electronics units (14a, 14b) are further adapted to control the operation of the corresponding compressor (13a, 13b) in response to a signal received from the other electronic unit (14a, 14b) . Thereby the control system (12) is adapted to control the operation of the two or more compressors (13a, 13b) in a mutually dependent manner.