We present an ameliorated arctangent algorithm based on phase-locked loop for digital Doppler signal processing,utilized within the heterodyne detection system. We define the error gain factor given by the approximati...We present an ameliorated arctangent algorithm based on phase-locked loop for digital Doppler signal processing,utilized within the heterodyne detection system. We define the error gain factor given by the approximation of Taylor expansion by means of a comparison of the measured values and true values. Exact expressions are derived for the amplitude error of two in-phase & quadrature signals and the frequency error of the acousto-optic modulator. Numerical simulation results and experimental results make it clear that the dynamic instability of the intermediate frequency signals leads to cumulative errors, which will spiral upward. An improved arctangent algorithm for the heterodyne detection is proposed to eliminate the cumulative errors and harmonic components. Depending on the narrow-band filter, our experiments were performed to realize the detectable displacement of 20 nm at a detection distance of 20 m. The aim of this paper is the demonstration of the optimized arctangent algorithm as a powerful approach to the demodulation algorithm, which will advance the signal-to-noise ratio and measurement accuracy of the heterodyne detection system.展开更多
分布式发电因可避免远距离电能输送而被重视,作为配套产品的并网控制器将有较大的市场需求空间。该设计围绕并网技术指标展开,旨在实现可靠并网发电。首先,基于软硬件锁相环研究提出并网监控设计方案。其次,在软件锁相环的DSP程序算法中...分布式发电因可避免远距离电能输送而被重视,作为配套产品的并网控制器将有较大的市场需求空间。该设计围绕并网技术指标展开,旨在实现可靠并网发电。首先,基于软硬件锁相环研究提出并网监控设计方案。其次,在软件锁相环的DSP程序算法中,利用移动平均滤波器的锁相环(moving average filter based PLL,MAF-PLL)作为小型双馈风力发电并网控制数据采集与检测技术;在硬件锁相环设计中,通过电压提取与比较、锁存、驱动触发多环节电路设计实现并网信息检测;硬软件锁相环结合用于实际双馈发电系统的定子电压控制。最后,基于可靠通信设计实现系统联调,电网侧与发电侧电压参数被准确采集与监控,相位差控制在13°以内,电压差在1%以内,指标基本符合国家标准。展开更多
基金supported by Key Research Program of Frontier Science,Chinese Academy of Sciences(Grant No.QYZDB-SSW-SLH014)the Yong Scientists Fund of the National Natural Science Foundation of China(Grant No.61205143)
文摘We present an ameliorated arctangent algorithm based on phase-locked loop for digital Doppler signal processing,utilized within the heterodyne detection system. We define the error gain factor given by the approximation of Taylor expansion by means of a comparison of the measured values and true values. Exact expressions are derived for the amplitude error of two in-phase & quadrature signals and the frequency error of the acousto-optic modulator. Numerical simulation results and experimental results make it clear that the dynamic instability of the intermediate frequency signals leads to cumulative errors, which will spiral upward. An improved arctangent algorithm for the heterodyne detection is proposed to eliminate the cumulative errors and harmonic components. Depending on the narrow-band filter, our experiments were performed to realize the detectable displacement of 20 nm at a detection distance of 20 m. The aim of this paper is the demonstration of the optimized arctangent algorithm as a powerful approach to the demodulation algorithm, which will advance the signal-to-noise ratio and measurement accuracy of the heterodyne detection system.
文摘分布式发电因可避免远距离电能输送而被重视,作为配套产品的并网控制器将有较大的市场需求空间。该设计围绕并网技术指标展开,旨在实现可靠并网发电。首先,基于软硬件锁相环研究提出并网监控设计方案。其次,在软件锁相环的DSP程序算法中,利用移动平均滤波器的锁相环(moving average filter based PLL,MAF-PLL)作为小型双馈风力发电并网控制数据采集与检测技术;在硬件锁相环设计中,通过电压提取与比较、锁存、驱动触发多环节电路设计实现并网信息检测;硬软件锁相环结合用于实际双馈发电系统的定子电压控制。最后,基于可靠通信设计实现系统联调,电网侧与发电侧电压参数被准确采集与监控,相位差控制在13°以内,电压差在1%以内,指标基本符合国家标准。
