基于光伏电池的输出特性设计了一套户用型新型单相两级式光伏并网发电逆变电源系统。该系统采用TMS320F2812 DSP作为核心处理器,前级采用改进的变步长扰动观察法控制策略的Boost DC/DC电路,后级采用智能功率模块IPM(Intelligent Power M...基于光伏电池的输出特性设计了一套户用型新型单相两级式光伏并网发电逆变电源系统。该系统采用TMS320F2812 DSP作为核心处理器,前级采用改进的变步长扰动观察法控制策略的Boost DC/DC电路,后级采用智能功率模块IPM(Intelligent Power Module)作为逆变主电路。该全桥逆变电路采用倍频单极性正弦脉宽调制方式,使用过零点检测电路配合电压电流双闭环反馈PI控制策略对DSP编程实现对电网频率和相位的跟踪调节。文中详细介绍了该逆变电源的硬件设计方法及其软件控制策略,研制了试验样机。实验结果证明该光伏并网逆变电源技术方案可行。展开更多
Utilizing the Young’s double slits and Mach-Zehnder interferometer, we proposed an experimental method to measure the generalized Stokes parameters of a radially polarized random electromagnetic beam. After the parti...Utilizing the Young’s double slits and Mach-Zehnder interferometer, we proposed an experimental method to measure the generalized Stokes parameters of a radially polarized random electromagnetic beam. After the partially coherent beam propagating through the Young’s double slits, the interference fringe is obtained by the help of a Mach-Zehnder interferometer consisting of apertures, quarter-wave plates and polarizers. The electric cross-spectral density matrix is detected by the coherence degree of interference fringe and the density of each single slit. The generalized Stokes parameters can be obtained from the electric cross-spectral density matrix. This experiment measures the generalized Stokes parameters of the random electromagnetic beam successfully. The results show that the spectral degree of coherence for copolarized cases (xx and yy) is similar with that for cross-polaried cases (xy and yx) for the radially polarized random electromagnetic beam. This method will help us determine the change of the polarization and coherence of the light in propagation by detecting the change of the generalized Stokes parameters.展开更多
文摘基于光伏电池的输出特性设计了一套户用型新型单相两级式光伏并网发电逆变电源系统。该系统采用TMS320F2812 DSP作为核心处理器,前级采用改进的变步长扰动观察法控制策略的Boost DC/DC电路,后级采用智能功率模块IPM(Intelligent Power Module)作为逆变主电路。该全桥逆变电路采用倍频单极性正弦脉宽调制方式,使用过零点检测电路配合电压电流双闭环反馈PI控制策略对DSP编程实现对电网频率和相位的跟踪调节。文中详细介绍了该逆变电源的硬件设计方法及其软件控制策略,研制了试验样机。实验结果证明该光伏并网逆变电源技术方案可行。
文摘Utilizing the Young’s double slits and Mach-Zehnder interferometer, we proposed an experimental method to measure the generalized Stokes parameters of a radially polarized random electromagnetic beam. After the partially coherent beam propagating through the Young’s double slits, the interference fringe is obtained by the help of a Mach-Zehnder interferometer consisting of apertures, quarter-wave plates and polarizers. The electric cross-spectral density matrix is detected by the coherence degree of interference fringe and the density of each single slit. The generalized Stokes parameters can be obtained from the electric cross-spectral density matrix. This experiment measures the generalized Stokes parameters of the random electromagnetic beam successfully. The results show that the spectral degree of coherence for copolarized cases (xx and yy) is similar with that for cross-polaried cases (xy and yx) for the radially polarized random electromagnetic beam. This method will help us determine the change of the polarization and coherence of the light in propagation by detecting the change of the generalized Stokes parameters.
