An all fiber pulsed coherent Doppler lidar （CDL） system at 1.54 μm wavelength is developed for wind profiles measurements. This lidar affords 43.0-μJ pulse energy at 10-kHz pulse repetition frequency with 500-ns p...An all fiber pulsed coherent Doppler lidar （CDL） system at 1.54 μm wavelength is developed for wind profiles measurements. This lidar affords 43.0-μJ pulse energy at 10-kHz pulse repetition frequency with 500-ns pulse width. The lidar is operated in monostatic mode with 50-mm diameter telescope. The heterodyne mixing signals are acquired with 500 M/s analog to digital converter and 2048 points fast Fourier transform （FFT） is implemented. Line of sight wind speeds are measured with more than 3.0-km range in a horizontal direction and about 1.9 km in the vertical direction with 75-m range resolution. Systematic error of speed measurement of 0.2 m/s is validated.展开更多
电能质量监测是改善供电电能质量,降低电力系统故障的必要手段。本文设计了在电能质量监测系统中,起至关重要作用的信号采集电路。它是以A D S8364芯片为核心,外加输入信号的滤波和放大电路,在硬件连接上,还采用PLL锁相环技术来实现系...电能质量监测是改善供电电能质量,降低电力系统故障的必要手段。本文设计了在电能质量监测系统中,起至关重要作用的信号采集电路。它是以A D S8364芯片为核心,外加输入信号的滤波和放大电路,在硬件连接上,还采用PLL锁相环技术来实现系统采样的逻辑控制,以达到同步的要求。最后结合实际电路,进行了系统的软件设计与实现。实践表明,该设计完全可以达到预期的采样精度,并能满足监测系统实时化的需要。展开更多
基金supported by the National Natural Science Foundation of China under Grant No.60908036
文摘An all fiber pulsed coherent Doppler lidar （CDL） system at 1.54 μm wavelength is developed for wind profiles measurements. This lidar affords 43.0-μJ pulse energy at 10-kHz pulse repetition frequency with 500-ns pulse width. The lidar is operated in monostatic mode with 50-mm diameter telescope. The heterodyne mixing signals are acquired with 500 M/s analog to digital converter and 2048 points fast Fourier transform （FFT） is implemented. Line of sight wind speeds are measured with more than 3.0-km range in a horizontal direction and about 1.9 km in the vertical direction with 75-m range resolution. Systematic error of speed measurement of 0.2 m/s is validated.
文摘电能质量监测是改善供电电能质量,降低电力系统故障的必要手段。本文设计了在电能质量监测系统中,起至关重要作用的信号采集电路。它是以A D S8364芯片为核心,外加输入信号的滤波和放大电路,在硬件连接上,还采用PLL锁相环技术来实现系统采样的逻辑控制,以达到同步的要求。最后结合实际电路,进行了系统的软件设计与实现。实践表明,该设计完全可以达到预期的采样精度,并能满足监测系统实时化的需要。
