【摘要】 设计了一种用于热能设备的火焰检测系统处理信号的方法。系统以AVR单片机为核心芯片,信号放大处理电路采用多级放大器与多路ADC通道相结合,实现自适应增益调整,以提高输入动态范围。火焰信号强度用输入信号的统计平均值表示,火焰信号的频率用快速傅里叶变换(FFT)进行分析计算。在FFT运算中,利用定点运算和查表法简化计算过程,降低资源消耗,提高运算速度,在300 ms时间内完成了512个采样点的定点FFT运算,频率分辨率为1 Hz,保证火焰信号检测的实时性、精度和可靠性。更多还原

【Abstract】 A method for signal processing of flame detection system for thermal energy equipment is presented. An AVR microcontroller unit( MCU) used as core chip,the multistage amplifiers combined with multiple ADC channels in signal amplification circuits are adopted to implement adaptive gain modulation and expand dynamic range of input. Statistical average of the input signals represents the flame signal intensity,and the flame signal frequency is analyzed and calculated by fast Fourier transform( FFT). During FFT calculation process,use fixpoint calculation and table lood-up method to simplify the calculation procedure,reduce resource consumption and improve arithmetic speed,fixed-point FFT of 512 samples is achieved within 300 ms with 1Hz frequency resolution,guarantee real-time,precision and reliability of flame signal detection.更多还原