Multi Air Conditioner Control for Mixed Indoor Unit Communication
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Solution Overview
Problem
The existing multi-room air conditioner systems face challenges in efficiently controlling the refrigerant flow to indoor units, especially when some units lack communication functions, leading to increased manufacturing costs and difficulties in operation, as they require various detectors and bidirectional communication capabilities.
Innovation Solution
A control method and system that organically control the refrigerant flow to indoor units with and without communication functions by variably controlling the frequency of an inverter-type compressor and adjusting the opening rate of expansion valves, using predetermined and detected temperature and overheating degree information to optimize refrigerant flow rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If indoor units are equipped with various detectors and bidirectional communication functions to enable efficient refrigerant flow control, then the control precision and system adaptability improve, but the device complexity and manufacturing costs increase
Solution Approach 1:
The patent extracts the communication function from the indoor unit, eliminating the need for detectors and bidirectional communication capabilities in indoor units. The outdoor unit independently determines refrigerant flow requirements by processing only power on/off signals from indoor units, thereby reducing device complexity and manufacturing costs while maintaining control precision.
2Adaptability or versatility
If all indoor units are equipped with communication functions to enable individual refrigerant flow control, then the system adaptability improves, but the ease of manufacture deteriorates due to increased component requirements
Solution Approach 1:
The outdoor unit is designed to handle multiple functions: it controls refrigerant flow to all indoor units, processes power on/off signals from both communicating and non-communicating indoor units, and independently determines the refrigerant flow rates required. This universal design allows the system to accommodate mixed indoor unit types without requiring communication functions in each unit, thereby improving ease of manufacture while maintaining system adaptability.
3Reliability
If the compressor operates at constant speed to maintain stable cooling output, then the reliability improves, but the energy efficiency deteriorates due to frequent on/off switching and high starting current
Solution Approach 1:
The patent employs an inverter-type compressor that dynamically adjusts its operating speed based on the refrigerant flow rates required by different indoor units. The controller varies the compressor speed to match the actual cooling demand, eliminating the need for frequent on/off switching and reducing starting current requirements. This dynamic control maintains reliable cooling output while significantly improving energy efficiency.
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 allows for efficient and flexible control of refrigerant flow, reducing the need for additional components and communication functions, thereby lowering manufacturing costs and enabling effective operation of both communicating and non-communicating indoor units within a multi-air conditioner system.
Implementation Method 1
Through use of an inverter that converts DC to a desired AC frequency, the inverter type compressor may exhibit variable operating performances
Implementation Method 2
an outdoor heat exchanger to perform heat-exchange between refrigerant and outside air via circulation of the refrigerant
Implementation Method 3
an expansion valve to depressurize the refrigerant
Implementation Method 4
a compressor to generate high-temperature and high-pressure refrigerant
Data Source
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AI summary
Disclosed herein is a control method of a multi air conditioner having a plurality of indoor units (200,300). The control method includes judging whether a first indoor unit (200) having a communication function with an outdoor unit (100) and a second indoor unit (300) having no communication function are operated, controlling driving of a compressor (105) at a predetermined frequency and an opening rate of a second flow-rate adjustable valve (130) based on predetermined compressor frequency, predetermined indoor information of the second indoor unit and outdoor information if solo operation of the second indoor unit is judged, controlling a frequency of the compressor based on capacities of the indoor units and indoor information if simultaneous operation of both the indoor units is judged, and controlling opening rates of first (125) and second (130) flow-rate adjustable valves based on indoor information, compressor frequency and outdoor information.