Effect of cooling method on power supply operating temperature
The heat dissipation of the power supply generally adopts two methods: direct conduction and convection conduction. Direct heat conduction is the transfer of heat energy along the object from the high temperature end to the low temperature end, and its heat conduction ability is stable. Convective conduction is the process in which the temperature of liquid or gas tends to be uniform through rotary motion. Since the convective conduction involves the power process, the cooling is relatively smooth.
The hair element is installed on the metal heat sink, and by extruding the hot surface, energy can be transferred from high and low energy bodies, and the energy that can be radiated by a large-area heat sink is not much. This heat conduction method is called natural cooling, and it has a longer delay time for heat loss. The amount of heat transfer Q=KA△t (K heat transfer coefficient, A heat transfer area, △t temperature difference), if the indoor ambient temperature is high, the absolute value of △t will be small, then the heat dissipation performance of this heat transfer method will be greatly reduced.
A fan is added to the power supply to quickly discharge the heat accumulated in the energy conversion out of the power supply. The continuous air supply of the fan to the heat sink can be regarded as convective transfer of energy. Known as fan cooling, this type of heat dissipation has short and long delay times. Heat dissipation Q=Km△t (K heat transfer coefficient, m heat transfer air quality, △t temperature difference), once the fan speed decreases or stops, the value of m will decrease rapidly, and the heat accumulated in the power supply will be difficult to dissipate , which will greatly increase the aging speed of electronic components such as capacitors and transformers in the power supply and affect the stability of their output quality, eventually leading to component burnout and equipment failure.
The main methods and advantages and disadvantages of communication power supply cooling
The design of cooling technology for communication switching power supply must first meet the various technical performance requirements of the industry. In order to better adapt to the special environment of the communication room, the cooling method is required to be highly adaptable to changes in the ambient temperature. At present, there are three commonly used cooling methods for rectifiers: natural cooling, pure fan cooling, and a combination of natural cooling and fan cooling. Natural cooling has the characteristics of no mechanical failure, high reliability; no air flow, less dust, which is conducive to heat dissipation; no noise. Pure fan cooling has light weight and low cost of equipment. The combination of fan and natural cooling technology has the characteristics of effectively reducing the size and weight of the device, the service life of the fan is long, and the self-adaptive ability of the fan fault is strong.
