Refrigerator Compressor RPM Control Without a Main Microcomputer
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Solution Overview
Problem
The high cost of installing a main microcomputer in refrigerators to control compressor on/off operations for temperature regulation, which increases manufacturing costs and energy inefficiency due to complex control systems.
Innovation Solution
A control method using a compressor microcomputer that adjusts the compressor's RPM based on previous operation rates, increasing RPM when the operation rate is high and reducing it when low, to maintain efficient temperature control without a main microcomputer, thereby simplifying the algorithm and reducing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a main microcomputer is installed to control compressor on/off operations for temperature regulation, then temperature control capability is improved, but manufacturing cost increases
Solution Approach 1:
The patent extracts the temperature control function from a separate main microcomputer and integrates it directly into the compressor controller. The compressor controller now independently monitors storage compartment temperature and controls compressor operation without requiring a dedicated main microcomputer, thereby reducing manufacturing costs while maintaining temperature control capability.
Solution Approach 2:
The patent merges the temperature control function with the compressor control function in a single controller unit. By combining these previously separate functions into one integrated controller, the system eliminates the need for a separate main microcomputer, reducing component count and manufacturing complexity while achieving both compression control and temperature regulation.
2Measurement precision
If a main microcomputer is installed to control compressor operations, then temperature control precision is improved, but device complexity increases
Solution Approach 1:
The patent extracts the temperature monitoring and control logic from a separate main microcomputer system and embeds it directly within the compressor controller. This extraction eliminates the need for complex inter-controller communication and reduces overall system complexity while preserving precise temperature control through direct integration of sensing and actuation functions.
Solution Approach 2:
The compressor controller is designed to perform multiple functions: it controls compressor operation, monitors storage compartment temperature, and regulates cooling cycles. By making the compressor controller a multi-functional universal controller, the system eliminates the need for separate dedicated temperature control hardware, reducing device complexity while maintaining control precision.
3Use of energy by moving object
If compressor operation is optimized by adjusting RPM based on operation rate, then energy efficiency is improved, but control algorithm complexity increases
Solution Approach 1:
The patent implements a feedback mechanism where the compressor controller monitors the operation rate (ratio of compressor running time to total cycle time) and uses this feedback to dynamically adjust compressor RPM. When operation rate exceeds a threshold, the controller reduces RPM to decrease cooling capacity and lower energy consumption, creating a self-regulating system that improves energy efficiency through simple threshold-based feedback control.
Solution Approach 2:
The patent changes the operational parameters of the compressor by dynamically adjusting RPM based on the monitored operation rate. Instead of maintaining constant high-speed operation, the system varies the rotational speed parameter in response to thermal conditions and operation rate, achieving energy efficiency through parameter optimization rather than complex control logic.
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 reduces manufacturing costs, improves energy efficiency by optimizing compressor operation, and allows for simplified temperature adjustment within the refrigerator, enabling efficient power consumption and reduced unnecessary cold air supply.
Implementation Method 1
a compressor which compresses a refrigerant circulating through a refrigeration cycle so that the refrigerant has a higher temperature and a higher pressure
Implementation Method 2
The refrigerant compressed in the compressor generates cold air while passing through a heat exchanger and the generated cold air is supplied to the freezing compartment or the refrigerating compartment
Data Source
AI summary
A control method includes initially operating a compressor at the same RPM as an operating RPM of the compressor during a previous cycle, adjusting the RPM in consideration of an operation rate of the previous cycle such that the RPM is increased when the operation rate is greater than a first set value, reduced when the operation rate is less than a second set value, and maintained when the operation rate is within a range between the first set value and the second set value, and operating the compressor at the adjusted RPM, the first set value being greater than the second set value.