Feedback unit manufacturers remind you that with the rapid development of China's economy, society, and science and technology, a large number of frequency converters are now used in various industries. Due to the wide range of applications of frequency converters and the vast territory of China, there are a large number of frequency converters working in extremely humid environments, such as those installed in humid and rainy coastal and southern regions, as well as wind turbine frequency converters installed near rivers, lakes, seas, and humid mountains.
Although the frequency converter can operate normally in these places, condensation may occur once there is a significant change in the working environment temperature due to the influence of air humidity. This will cause a certain amount of liquid water to be generated in the power components, circuit boards, and other parts of the frequency converter. After mixing with the accumulated dust inside, it will affect its electrical insulation and, in severe cases, create pathways, leading to malfunctions and affecting normal operation.
The phenomenon of condensation can seriously affect and threaten the normal and stable operation of the frequency converter. If the frequency converter operates in a humid environment, especially in the rainy southern region in summer, correct measures must be taken to prevent and eliminate condensation. At present, there are only two commonly used methods for preventing condensation, namely temperature control and humidity control. The former aims to reduce relative temperature, while the latter aims to reduce relative humidity.
1、 Temperature control method
Preventing the formation of condensation can be achieved by disrupting the conditions for condensation formation. Due to the relatively enclosed interior of the inverter cabinet, if the cabinet temperature can always be kept above the dew point temperature, condensation will not occur. At present, there are mainly two temperature control schemes:
1. Install a filter at the ventilation opening to prevent a large amount of dust from entering the interior of the frequency converter, ensuring IP protection level; Set a heater for the frequency converter to start heating once the humidity is too high, and increase ventilation when the temperature rises; This ensures that the relative humidity of the air inside and outside the frequency converter remains consistent, and the temperature remains within the normal range.
2. La capacité de refroidissement interne du convertisseur de fréquence est relativement contrôlable, garantissant ainsi le maintien de la température à l'intérieur de l'armoire dans une certaine plage. Lorsque l'humidité dépasse un certain seuil, la capacité de dissipation thermique du convertisseur est réduite et l'énergie qu'il consomme est utilisée pour augmenter la température interne de l'armoire, empêchant ainsi la condensation. Lorsque la température dépasse un certain seuil, la capacité de dissipation thermique est augmentée afin d'éviter toute surchauffe susceptible de perturber le fonctionnement normal du convertisseur.
2. Méthode de contrôle de l'humidité
En réduisant la teneur en vapeur d'eau et en abaissant efficacement l'humidité relative de l'air, on peut prévenir l'apparition de condensation, principalement grâce aux trois procédés suivants :
1. Méthode de déshumidification par différence de température : Installer un dissipateur thermique à l’intérieur du convertisseur de fréquence. Ce dissipateur favorise la condensation, qui se forme uniquement sur celui-ci et non dans les autres parties du convertisseur. L’eau condensée est évacuée par l’orifice de sortie afin de maintenir un environnement relativement sec à l’intérieur de l’armoire.