Research And Implementation Of Isolated Feedback System For High-temperature Switching Power Supply

Along with the progress and development of an era,human exploration of technology is endless.Now,the pursuit of power supply is not merely being able to be used,but small,high frequency,high efficiency.In the field of application,power supply also gradually to pioneer areas such as aerospace,oil exploration,the electric cars and so on,which constantly accompanied by high temperature,strong radiation and other harsh conditions.In the light of short working hours for the power of the ordinary,the switching power supply at high temperature is emerging.With the exploit of these markets continuously,the market of high-temperature switching power supply will become larger and larger.In so many of difficulties in designing of the high temperature switch power supply,the design of the power feedback circuit is a vital part undoubtly.Good feedback circuit can guarantee the stability of the output voltage,provides the high quality of power supply for subsequent devices.Unfortunately,there are only a few isolated options available in the existing high temperature solutions,which are not only expensive but also limit the design range of high-temperature switching power.In order to solve the above problems effectively,the aims in this article is to design a isolation feedback module which can work well in high temperature environment,of course,it also can as decrease the cost of the application of power as possible.Accessing to relevant information and so many of documents,first of all,the article carried on the detailed research analysis in development status and prospect of the existing high temperature switching power supply feedback system.Through analyzing the feedback scheme and comparing the pros and cons of each solution,it was found that the magnetic coupling isolation feedback was most suitable work in high temperature environment,which also only one able to be structured using discrete devices.Then,making sure the work well in the high temperature environment,the existing feedback schemes was redesigned.Additionally,the study designed of magnetic coupling isolation feedback circuit principle diagram,and verified its feasibility through the simulation software.At length,the printed circuit board was made,and the validity was also proved through physical tests.Finally,the test prototype of the design power source is designed with anti-excitation circuit topology.In this paper,the theoretical derivation of the anti-excitation topology is carried out,and the parameter is calculated for the anti-shock power supply module,which provides the theoretical basis for the selection of devices in the circuit.The test prototype and feedback module are integrated into a piece of PCB,and the testing process includes normal temperature test and high temperature test。Then the key point test waveforms in the process and relevant data are recorded to summarized and analyzed.The experimental results show that the magnetic coupling isolation feedback circuit can work steadily in high temperature environment and meet the design expectations.