Study on Air Duct Conversion and Extension Diagnosis of Booster Equipment in Audio Management Module of Airborne Electronic Equipment

In view of the failure situation that the air duct conversion structure in the audio management module cabin and the booster equipment conflict with each other in the functions of boosting ventilation and heat exchange ventilation, the air duct conversion mechanism arranged at the front end of the booster fan can realize the switching of external circulation, internal circulation and internal-external mixed circulation ventilation, and can adjust the ventilation volume of fresh air according to the actual working conditions.In this study, the ventilation booster adopts PWM speed regulation, and the power switch of the fan adopts self-developed intelligent power electronic switch, which can realize the overall power supply on-off control of the fan, and the speed of the fan is adjusted by PWM signal duty ratio, thus realizing the stepless speed regulation of 0~100% of the fan speed.The PWM speed control method fills the gap in this field and is more efficient than the traditional method to solve the conflict problem.Onestage power supply on-off control, two-stage speed adjustment control and two-stage control improve the reliability of the control circuit.The difficulty of integrating the two systems lies in the matching of air demand and fan performance in different working modes.Through the calculation of air duct resistance, booster ventilation and heat exchange ventilation in different working modes of air conditioning evaporation unit, reasonable fan performance parameters are obtained to guide the matching design of fans, thus eliminating the difficulty of conflict between booster ventilation and heat exchange ventilation.