Sinrace Power Supply Technology (Shenzhen) Co., Ltd.

1. Natural cooling
Natural cooling method is the traditional switching power supply cooling earlier, this approach relies mainly on the large metal heat sink to direct heat conduction cooling. Heat Q = KA △ t (K heat transfer coefficient, A heat transfer area, △ t temperature difference). When the rectifier output power increases, its temperature will increase the power components, △ t temperature difference also increased, so when the rectifier is sufficient heat transfer area A, its heat is no time lag, a small temperature difference between the power components, the thermal stress and small heat shock. But the main drawback of this approach is the large heat sink size and weight. Transformer winding to minimize temperature rise and prevent the rise in temperature affect their work performance, so the margin of its large choice of materials, transformer size and weight are great. Rectifier high cost of materials, maintenance or replacement is not convenient. Because of its less demanding on the environment clean, the current power supply for small-capacity communication, professional communication in the network there are some small part of the application, such as electricity, petroleum, broadcasting, military, water, national security, public security and so on.

2. Fan cooling
With the development of manufacturing technology fan, fan of the work life of greater stability and progress, its MTBF is 50,000 hours. After the use of less bulky cooling fan radiator, making the converter volume and weight greatly improved raw material costs are greatly reduced. As market competition intensifies, the market prices decline, this technology has become a major trend.      The main disadvantage of this approach is the fan MTBF 100,000 hours over the rectifier short time after the power supply fan failure if the failure rate of impact. Therefore, in order to ensure the life of the fan, the fan speed is changed with the temperature inside the device and change. The amount of heat Q = Km △ t (K heat transfer coefficient, m heat air quality, △ t temperature difference). m heat exchanger and fan air quality is speed related, when the rectifier output power increases, its temperature will increase the power components, and power to the rectifier element temperature can detect this change, to increase the fan speed to enhance the heat dissipation in time is a big lag. If the load is often mutated, or large fluctuations in the mains input, it will cause a rapid component of hot and cold power variation, mutation, semiconductor temperature difference thermal stress and thermal shock will cause the component parts of different materials, stress cracks. So that premature failure.

3. the combination of fan and natural cooling

As the ambient temperature changes and load changes, the power dissipation of energy at work, use fans and natural cooling combined heat can be distributed out faster. In this way, while increasing the cooling fan, radiator area can be reduced, making the power components work in a relatively stable temperature conditions, life will not be affected by external conditions change. This will not only overcome the limitations of the fan cooling the power components of the shortcomings of thermal regulation lag, but also low-impact life to avoid the fan's overall reliability of the rectifier. Especially in the room temperature is unstable, the use of a combination of cold air and self-cooling technology has better cooling performance. In this way the cost of materials rectifier cold to go in a pure and natural cooling fan between the two modes, low weight, easy maintenance.

Especially in the use of smart air-cooled and self-cooling technology, allowing rectifiers at low load operating conditions, the module temperature rise is small, the fan at low speed state of the module. In the high-load operating conditions, the module temperature. Module temperature exceeds 55 ℃. Fan speed increases linearly with temperature changes. Reign fan failure detection, fan failure, fan failure, limiting output, and fault alarm. As the fan running several times the size of the load-related, making the fan's life when longer than that of pure air, its reliability is greatly enhanced