Application of Thermal Imager in Power Supply Stability Design

Power supply is an important part that all electrical appliances must have. In the electronic equipment industry, people compare the power module to the "heart" of electronic equipment and electronic systems, and the power supply is also the link that carries the most power in the electrical system. Power

supply analysis

In recent years, power supply equipment has become increasingly complex, the variety and quantity of components have increased rapidly, the use environment has become harsh and diverse, and the electronic systems it serves have become more and more important and expensive, especially military equipment, especially the requirements for the reliability of components and systems in aviation and aerospace. The

task of the power supply in the electrical system is to provide electrical energy for various circuits in the electrical system. Since the types of circuits have different functions, the power supply can be divided into: UPS power supply, EPS power supply, voltage-stabilized power supply, frequency conversion power supply, purification power supply, special power supply, generator set, switching power supply (AC/DC), inverter power supply (DC/AC), module power supply (DC/DC) and other power supplies according to different supply methods.

What are the applications of thermal imagers in power supplies?

Temperature control of power supply is an important way to improve the reliability and service life of power modules and systems. In the design and application of power supplies, choosing appropriate components, that is, reducing circuit losses and improving module conversion efficiency, and choosing a reasonable cooling method are key technologies to ensure reliable and stable operation of the power supply. The organic combination of the two will make the power supply have technical advantages such as stronger environmental adaptability, long life, low cost, and easy maintenance.

Thermal imagers can provide clear images of the temperature field distribution of the power circuit and the entire power system and accurate temperature measurement.

1)

The power supply of electronic components is an electric energy conversion device. It consumes some electric energy during the conversion process, and this electric energy is converted into heat and released. The working stability and aging speed of electronic components are closely related to the ambient temperature. Whenever the ambient temperature rises by 10°C, the life of the main power components is reduced by 50%, which requires that electronic components should work in a relatively stable and low temperature range.

The thermal imager can provide engineers with a heat map of the heating conditions of each component in the circuit during operation, helping engineers analyze the impact of components on the temperature of the entire power circuit, and also helping engineers select conversion modules with appropriate load capacity.

2) Transformer

The transformer is the main component of the power supply, and its heating temperature is limited. The current domestic 3C certification limits the transformer temperature to 120°C, and the European UL certification limits the transformer temperature to 115°C. The main source of heat for the power supply is also the transformer, and the core loss and copper wire loss are the main reasons for the temperature rise of the transformer. In addition, as the operating temperature of the transformer increases, the core load will inevitably weaken and the coil will age. When its insulation performance decreases, the ability to resist the impact of the main power will be weakened. At this time, if there is a lightning strike or a main power surge, the high reverse voltage at the primary of the transformer will break down the transformer, causing the power supply to fail. At the same time, there is a risk of high voltage entering the main equipment, causing damage to the main equipment. [page]

The thermal imager can provide accurate transformer temperature through quick and easy operation.

3) Circuit heat distribution:

The components of the same circuit board should be arranged according to their heat generation and heat dissipation as much as possible. The reasonable arrangement of components can effectively reduce the temperature rise of the printed circuit, thereby significantly reducing the failure rate of components and equipment.

The thermal imager can help engineers analyze the temperature distribution of the entire circuit board through the infrared heat map provided, and improve the engineers' design and application.

4) Power supply cooling

Power supply cooling technology is the basic means to meet the technical performance requirements of the industry. At present, the commonly used cooling methods for various power modules are natural cooling, pure fan cooling, and a combination of natural cooling and fan cooling.

There is a large transformer and some large capacitors in the power supply product, which are large heat sources. These heat sources may have a great impact on the stability and service life of some other circuits and components inside your product. Using an infrared thermal imager, the heating and heat dissipation conditions in three situations can be measured very directly. Engineers can improve the design and use reasonable cooling methods in actual applications to improve the reliability and stability of the power supply and reduce the failure rate of the equipment.

5) Process improvement

When processing power supply equipment, process problems are prone to occur at the joints and crimping points. The use of thermal imagers can easily, intuitively and safely find the fault points, helping production personnel and quality inspection personnel to better find and solve problems and improve product quality. [page]

In addition to the R&D department, the application departments of thermal imagers in power supply companies also include: quality control department, after-sales service department and equipment maintenance department.

Unique Applications of Infrared Thermal Imagers

1. Existing temperature analysis tools

For power supply in R&D and application, due to its particularity, many engineers will complain that the existing means are difficult to support them in a detailed and comprehensive temperature field description, and the operation is inconvenient and may change the original temperature field distribution. For example: Currently in power supply development and application, the tool for temperature analysis is the data logger, but the use of the data logger may encounter the following problems: circuit board power failure, insufficient number of SMD thermocouples, inconvenient operation, slow response time (30 seconds to 1 minute), the use of the data logger will also change the heat dissipation of the measured device, and it is also impossible to analyze the temperature field distribution and heat dissipation analysis of the entire power supply.

2. Advantages of thermal imager temperature analysis

Compared with data loggers and infrared spot thermometers, infrared thermal imagers have their own advantages:

a) When detecting the target circuit with an infrared thermal imager, there is no need to turn off the power, which is easy to operate, and the non-contact measurement prevents the original temperature field from being disturbed;

b) The response speed is fast, less than 1 millisecond;

c) Using the supporting infrared analysis software, users can conduct a detailed and comprehensive analysis of the obtained power supply temperature data without being on site, and generate a complete temperature report.

This article summarizes

that thermal imagers can play their superiority in the power supply industry. Due to its unique advantages, it can supplement the deficiencies of traditional detection methods. However, there is still a lot of work that needs to be further improved and improved in future practice, so that the application of infrared thermal imaging technology in the power supply industry will be more extensive and scientific, effectively improving the quality of power supply products, improving the efficiency of power conversion, and improving the system performance level. (end)