Dynamic Cooling Control for Microwave Magnetron Efficiency

Solution Overview

Problem

Existing microwave oven cooling systems are inefficient and noisy due to their static nature, consuming excessive energy and failing to adapt to changes in microwave source efficiency or load conditions.

Innovation Solution

A dynamic cooling control system that adjusts the cooling of the microwave source based on its efficiency, using sensors and control units to monitor temperature derivatives, power levels, and reflected microwave power, allowing for optimized energy consumption and reduced noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a static cooling system is used with constant fan speed throughout operation cycle, then the microwave source is adequately cooled under all conditions, but energy consumption increases and noise level rises

Engineering Contradiction:

Improvecooling adequacyVSAvoidenergy consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The cooling system transitions from static to dynamic operation by continuously adjusting fan speed based on real-time microwave source efficiency measurements. The control unit modulates the fan motor speed to match actual cooling requirements, enabling the system to operate at lower speeds when less cooling is needed and maintain adequate cooling when required, thereby reducing overall energy consumption while preserving cooling adequacy.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system implements a feedback control mechanism where the microwave source efficiency is continuously monitored and used to adjust the cooling system operation. The control unit receives efficiency data from the microwave source and dynamically adjusts fan speed in response, creating a closed-loop system that optimizes energy consumption based on actual cooling needs rather than operating at constant high speed.

Inventive Principle:

Principle #23Feedback

2Reliability

If a static cooling system operates at highest cooling level throughout operation cycle, then the microwave source is adequately cooled under all conditions, but noise production increases

Engineering Contradiction:

Improvecooling adequacyVSAvoidnoise

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The cooling system transitions from static to dynamic operation by continuously adjusting fan speed based on real-time microwave source efficiency measurements. The control unit modulates the fan motor speed to match actual cooling requirements, enabling the system to operate at lower speeds when less cooling is needed and maintain adequate cooling when required, thereby reducing overall energy consumption while preserving cooling adequacy.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system implements a feedback control mechanism where the microwave source efficiency is continuously monitored and used to adjust the cooling system operation. The control unit receives efficiency data from the microwave source and dynamically adjusts fan speed in response, creating a closed-loop system that optimizes energy consumption based on actual cooling needs rather than operating at constant high speed.

Inventive Principle:

Principle #23Feedback

3Adaptability or versatility

If cooling is controlled based on power output level, then the cooling level matches power output changes, but the control accuracy decreases when efficiency variations occur

Engineering Contradiction:

Improvecooling adaptation to power outputVSAvoidcooling control accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The system implements a feedback control mechanism where the microwave source efficiency is continuously monitored and used to adjust the cooling system operation. The control unit receives efficiency data from the microwave source and dynamically adjusts fan speed in response, creating a closed-loop system that optimizes energy consumption based on actual cooling needs rather than operating at constant high speed.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The control parameter for cooling adjustment changes from power output level to microwave source efficiency. This parameter change enables more accurate control because efficiency directly reflects the actual thermal state and cooling requirements of the microwave source, accounting for variations in operating conditions that power output alone cannot capture.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS11818826B2Methods of controlling cooling in a microwave heating apparatus and apparatus thereof

Publication Date: 2023.11.14 WHIRLPOOL CORP

AI summary

A microwave heating apparatus and methods of controlling cooling of a microwave heating apparatus are provided. The microwave heating apparatus typically includes a microwave source for generating microwaves, a cooling unit for cooling the microwave source and a control unit. According to one embodiment, the control unit is configured to receive operational data from a measuring device indicative of the measured power of microwaves transmitted from the magnetron and receive operational data from the measuring device indicative of the measured anode current of the magnetron. A calculating device calculates an efficiency of the magnetron as a function of the measured power of the transmitted microwaves and the measured anode current, to define a determined efficiency. The control unit controls the cooling unit and cools the magnetron based on the determined efficiency.