直升机机内PWM照明调光系统产生音频干扰问题的研究

Research of Acoustic Disturbance Introduced by the PWM Illumination and Light-adjusting System in Helicopter

在直升机机内照明调光领域,国外军机已广泛采用脉冲宽度调制(PWM)调光方式。PWM调光方式相比传统线性调光方式具有以下明显优点:效率高,调光范围宽,功耗小,带载能力强,附加损耗小等。但PWM调光系统的不足是电磁辐射,尤其会对机内通话系统产生音频干扰,在机通耳机中会出现明显干扰声,影响机内通话质量。本方案能有效抑制PWM调光系统的音频干扰噪声,消除耦合到机通耳机的干扰杂声。

Pulse Wavelength Modulation（PWM ）has been widely used in the field of illumination and light-adjusting in foreign helicopters. PWM has more obvious virtues than the traditional linear light-adjusting method such as higher efficiency, a wider adjusting range, lower power consumption, stronger load-carrying capacity and lower additional load consumption, and so on. But the PWM light-adjusting system can be affected by the electromagnetic radiation, which brings acoustic disturbance to the communication system and noises to the earphone and thus reduces communication quality. The new scheme we adopt can suppress the acoustic disturbance of PWM light-adjusting system and eliminate the noise coupled to the earphone.