Indroduction of Power Supply Converter cooling
As a conversion device, motor frequency converter will produce certain power consumption during operation. This part of power consumption will vary according to different loads, different control modes, and different brands and specifications of frequency converters. The data shows that the power consumption of the frequency converter is about 4 ~ 5% of its capacity. Among them, the inverter part accounts for about 50%, the rectifier and DC circuit account for about 40%, and the control and protection circuit accounts for 5 ~ 15%.
When the device temperature is reduced by 10 ℃, the reliability of the device will be doubled. It can be seen that the frequency converter can reduce the temperature rise and improve the reliability of the device, so as to prolong the service life of the equipment.
The heat dissipation of frequency converter is divided into the following categories: natural cooling, forced air cooling and liquid cooling.
Natural Cooling:
Small capacity frequency converter generally adopts natural heat dissipation, and its use environment should be well ventilated and free of dust and floating objects that are easy to adhere. The driving objects of this kind of frequency converter are mostly air conditioning fans, machine tool engraving machines, etc. It has low power and excellent use environment.
In addition, the capacitance of frequency converters with natural heat dissipation is not always small. For low-capacity frequency converters, we can choose the general radiator, and it is required to expand the heat dissipation area as much as possible within the allowable range, and the spacing between heat sinks should be small to increase the heat dissipation area as much as possible. For large capacity frequency converter, if natural heat dissipation is required, it is recommended to use heat pipe radiator. Heat pipe radiator is a new generation of radiator. It is the product of the combination of heat pipe technology and radiator technology. Its heat dissipation efficiency is very high.
Forced air cooling:
Forced air cooling refers to the method of directly cooling the equipment shell through one or more external fans. Because the frequency converter will inevitably produce more heat when working, especially when it operates at full load for a long time and the ambient temperature is too high. Therefore, in order to prevent serious overheating of the frequency converter, we can also add one or more fans to directly cool the frequency converter shell. This cooling method has low cost. At the same time, without considering the cost, the number of fans can be added at will to strengthen the cooling effect.
Liquid cooling:
Liquid cooling has a liquid inlet and outlet, and there are multiple waterways inside the radiator, which can give full play to the advantages of water cooling and take away more heat. This is the basic principle of liquid-cooled radiator. Liquid cooling is a common way of industrial cooling, but for frequency converter equipment, it is rarely used for heat dissipation, because of its high cost and large volume. In addition, the capacity of general frequency converter ranges from thousands of VA to nearly 100 KVA, which is difficult for users to accept the cost performance. This way is only used in special occasions and frequency converters with great capacity.
No matter which thermal solution is adopted, the power consumption shall be determined according to the capacity of the motor frequency converter, and the appropriate fan and radiator shall be selected to achieve excellent cost performance. At the same time, the environmental factors used in the frequency converter shall be fully considered. Corresponding measures must be taken to ensure the normal and reliable operation of the frequency converter.
