基于DDS的飞机供电系统测试信号源的设计

介绍基于直接数字频率合成(DDS)的飞机供电系统测试信号源工作原理,提出以FPGA+单片机实现三相正弦测试信号源.针对DDS电路输出波形杂散度受ROM内存容量有限的限制,采用两片ROM存储一个周期的正弦波数据,减小了高位截断杂散.实验检测结果显示,信号发生器能输出频率准确度≤±0.1％,幅值准确度≤±3％,相位准确度≤±1％的三相正弦波形.

Design of the aircraft power supply system based on DDS test signal source

This paper introduces the working principle of the test signal source of the aircraft power supply system based on DDS,and presents the realization of the three-phase sine test signal source with FPGA+MCU.In view of the limitation of DDS (direct digital synthesis) circuit output waveform is limited by the limited memory capacity of ROM,the two ROM is used to store the sine wave data of one period,which reduces the high truncation spurious.The experimental results showed that the signal generator can output frequency accuracy of less than 0.1 ％,the amplitude accuracy of less than 3％,the three-phase sine wave phase accuracy is less than 1％.