Device of Active Noise Control in Duct of Power Plant with Increased Protection

Low frequency noise generated in ducts during power plants operation may achieve significant values and may cause serious health problems of population and industrial staff. Active noise control is a promising method for low frequency noise reduction, but in conditions of exploitation of active noise control devices in industry, transport etc. the problem of influence of external factors to the efficiency, reliability and durability of active noise control devices is arising. Factors influencing to the operation of active noise control devices are analyzed. New device of active noise control in duct with improved protection is suggested. Construction and principle of operation of device are described. For the purposes of protection from negative impact of external sources (like temperature, humidity, masking interferences of other noise sources etc.) the elements of generation and of correction of active sound source with required acoustical characteristic are placed in proof housing in which also additional pressure sensor is installed. Such construction of device is giving the possibility of it efficient operation and low frequency noise reduction in different conditions of exploitation.