Method and device for measuring the temperature in electric power resistors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for measuring the temperature of tubular housed electric power resistors, such as using thermocouples or thermal sensors, are difficult to implement and often require expensive equipment or are limited to specific temperature ranges, especially when the resistors have steel sheaths or etched foil technology.
Innovation Solution
A method and device that measure the high-frequency circuit parameters of power resistors, including resistance, conductance, inductance, and capacitance, to determine temperature without the need for thermocouples, thermal sensors, or thermo chambers, by analyzing the trends of these parameters as a function of frequency and temperature.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If temperature measurement is performed using existing methods (thermocouples, infrared cameras, thermal imaging devices), then temperature can be detected, but the measurement precision is insufficient for accurately detecting temperature distribution in power resistors
Solution Approach 1:
The patent introduces a light source as an intermediary to illuminate the power resistor surface, enabling the camera to capture reflected light that carries temperature information. This intermediary approach allows indirect temperature measurement with higher precision than direct thermal sensing methods.
Solution Approach 2:
The patent replaces contact-based mechanical measurement systems (thermocouples) with optical-based non-contact measurement (camera with light source), eliminating physical interference and enabling accurate temperature distribution mapping without affecting the resistor's electrical or thermal state.
2Volume of moving object
If power resistors are designed with high power density to reduce size, then space utilization improves, but temperature distribution becomes more complex and difficult to detect
Solution Approach 1:
The patent transitions from point-based temperature measurement to surface-wide temperature distribution mapping by capturing two-dimensional images. This dimensional expansion allows comprehensive monitoring of temperature fields in compact high-power-density resistors, revealing spatial patterns that single-point measurements cannot detect.
Solution Approach 2:
The patent creates a visual copy (image) of the temperature distribution on the resistor surface by capturing reflected light patterns. This optical copy provides a complete map of temperature variations across the entire surface, enabling analysis of heat distribution patterns in miniaturized resistors without physical contact.
3Device complexity
If conventional measurement methods are used, then device complexity is low, but the ability to detect localized overheating and potential failure points is insufficient
Solution Approach 1:
The patent makes the measurement system universal by using a standard camera and light source that can detect temperature distribution across the entire resistor surface simultaneously. This multi-functional approach allows a single device to perform what would otherwise require multiple specialized sensors, maintaining simplicity while enhancing detection capability.
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
Enables accurate temperature measurement of power resistors across a wide range of temperatures (0°C to 700°C) without the limitations of traditional methods, using a device that can be integrated into the resistor's control circuit or used as a retrofit, providing a cost-effective and versatile solution.
Implementation Method 1
obtaining an image of the power resistor by using a camera to take a picture of a light reflection of the power resistor
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The present invention relates to a method and device for measuring the temperature in power resistors based on the measurement of the high-frequency circuit parameters of said resistor. The present invention excludes the use of thermocouples, dedicated temperature sensors or thermo chambers.