The braking unit supplier reminds you that the frequency converter, as a conversion device, will generate a certain amount of power consumption during operation. This part of power consumption will vary depending on the load, control method, brand and specifications of the inverter. The data shows that the power consumption of the frequency converter is about 4-5% of its capacity. 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%. The 10 ℃ rule states that when the device temperature drops by 10 ℃, the reliability of the device will double. From this, it can be seen how important it is for frequency converters to reduce temperature rise, improve device reliability, and thus extend the service life of equipment, in order to better serve society.
Classification of heat dissipation methods
The heat dissipation of frequency converters can be divided into the following types: natural heat dissipation, forced air cooling, and water cooling.
Natural heat dissipation
Small capacity frequency converters generally use natural heat dissipation, and their operating environment should be well ventilated, free of dust and easily attached floating objects. The dragging objects of this type of frequency converter are mostly air conditioning fans, machine carving machines, etc. It has low power and excellent usage environment.
In addition, the capacitance of frequency converters using natural heat dissipation methods is not always small. For low capacity frequency converters, we can choose a general heat sink and require that the heat dissipation area be expanded as much as possible within the allowable range. The spacing between the heat sinks should be small to maximize the heat dissipation area. For large capacity frequency converters, if natural heat dissipation is required, it is recommended to use heat pipe radiators. Heat pipe radiator is a new generation of radiator, which is a product of the combination of heat pipe technology and radiator technology. Its heat dissipation efficiency is extremely high.
Forced air cooling
Forced air cooling refers to the method of directly cooling the equipment casing through one or more external fans. Due to the fact that frequency converters inevitably generate a significant amount of heat during operation, especially during long-term full load operation and when the ambient temperature is too high. Therefore, in order to prevent severe overheating of the inverter, we can also add one or more fans to directly cool down the inverter casing. This cooling method is low-cost, and at the same time, the number of fans can be freely added to enhance the cooling effect without considering the cost.
water cooling
Water cooling has an inlet and outlet, and there are multiple water channels inside the radiator, which can fully utilize the advantages of water cooling and take away more heat. This is the basic principle of water-cooled radiators. Water cooling is a common method of industrial cooling, but for frequency converter equipment, using this method for heat dissipation is minimal due to high cost, large size, and the fact that the capacity of general frequency converters ranges from several thousand volt amperes to nearly 100 kilovolt amperes, making it difficult for users to accept cost-effectiveness. This method is only used in special occasions and for frequency converters with large capacity.
Regardless of the heat dissipation method used, the power consumption of the motor frequency converter should be determined based on its capacity to choose the appropriate fan and heat sink, in order to achieve excellent cost-effectiveness. At the same time, environmental factors used in frequency converters should be fully considered. Corresponding measures must be taken to ensure the normal and reliable operation of the frequency converter in harsh environments such as high temperature, high humidity, coal mines, oil fields, and offshore platforms. From the perspective of the frequency converter itself, it is advisable to avoid the influence of adverse factors as much as possible. For example, it can seal the influence of dust and sand, and only the air duct of the radiator is in contact with the outside air, avoiding any impact on the interior of the frequency converter; For salt spray and humidity, all components of the frequency converter can be insulated and sprayed. For on-site operation frequency converters, measures should be taken to prevent rain, sun, fog, and dust. For high temperature and high humidity environments, air conditioning and other equipment can be added for cooling and dehumidification, providing a good environment for the frequency converter and ensuring its reliable operation. Discussion on the heat dissipation effect and selection principles of radiators.