针对多直驱永磁风机(direct-drive permanent magnetic synchronous generators, D-PMSGs)经柔性直流(voltage source converter based high voltage direct current,VSC-HVDC)输电并网引发的次同步振荡(sub-synchronous oscillation,S...针对多直驱永磁风机(direct-drive permanent magnetic synchronous generators, D-PMSGs)经柔性直流(voltage source converter based high voltage direct current,VSC-HVDC)输电并网引发的次同步振荡(sub-synchronous oscillation,SSO)问题,建立D-PMSGs经VSC-HVDC并网系统的动态模型,通过特征值分析研究系统中存在的SSO模式及相关参与因子。结果表明,系统中存在由风电场内风机之间相互作用产生的场内SSO1模式,以及风电场与外部柔直电网相互作用产生的场网SSO2模式。其中SSO1模式主要受D-PMSGs网侧换流器定直流电压控制环节的影响,SSO2模式主要受D-PMSGs网侧换流器定直流电压控制环节和VSC-HVDC送端整流器定d轴交流电压控制环节的影响。因此,SSO1模式和SSO2模式之间对于D-PMSG参数的变化存在阻尼耦合。进一步分析了D-PMSG参数变化对2种SSO特性的影响,表明阻尼耦合的影响趋同。在PSCAD/EMTDC中搭建D-PMSGs经VSC-HVDC并网系统的时域仿真模型,验证了理论分析结果的正确性。展开更多
Mesoscopic damped mutual capacitance coupled double resonance circuit is quantized by the method of damped harmonic oscillator quantization. Hamiltonian is diagonalized by the method of unitary transformation. The ene...Mesoscopic damped mutual capacitance coupled double resonance circuit is quantized by the method of damped harmonic oscillator quantization. Hamiltonian is diagonalized by the method of unitary transformation. The energy spectra of this circuit are given. The quantum fluctuations of the charge and current of each loop are investigated by the method of thermo- field dynamics (TFD) in thermal excitation state,thermal squeezed vacuum state, thermal vacuum state and vacuum state. It is shown that the quantum fluctuations of the charge and current are related to not only circuit inherent parameter and coupled magnitude, but also quantum number of excitation, squeezed coefficients, squeezed angle and environmental temperature. And the quantum fluctuations increase with the increase of temperature and decay with time.展开更多
文摘针对多直驱永磁风机(direct-drive permanent magnetic synchronous generators, D-PMSGs)经柔性直流(voltage source converter based high voltage direct current,VSC-HVDC)输电并网引发的次同步振荡(sub-synchronous oscillation,SSO)问题,建立D-PMSGs经VSC-HVDC并网系统的动态模型,通过特征值分析研究系统中存在的SSO模式及相关参与因子。结果表明,系统中存在由风电场内风机之间相互作用产生的场内SSO1模式,以及风电场与外部柔直电网相互作用产生的场网SSO2模式。其中SSO1模式主要受D-PMSGs网侧换流器定直流电压控制环节的影响,SSO2模式主要受D-PMSGs网侧换流器定直流电压控制环节和VSC-HVDC送端整流器定d轴交流电压控制环节的影响。因此,SSO1模式和SSO2模式之间对于D-PMSG参数的变化存在阻尼耦合。进一步分析了D-PMSG参数变化对2种SSO特性的影响,表明阻尼耦合的影响趋同。在PSCAD/EMTDC中搭建D-PMSGs经VSC-HVDC并网系统的时域仿真模型,验证了理论分析结果的正确性。
基金the Natural Science Foundation of Heze University ofShandong Province, China (No.XY05WL01) and the UniversityExperimental Technology Foundation of Shandong Province, China(No.S04W138)
文摘Mesoscopic damped mutual capacitance coupled double resonance circuit is quantized by the method of damped harmonic oscillator quantization. Hamiltonian is diagonalized by the method of unitary transformation. The energy spectra of this circuit are given. The quantum fluctuations of the charge and current of each loop are investigated by the method of thermo- field dynamics (TFD) in thermal excitation state,thermal squeezed vacuum state, thermal vacuum state and vacuum state. It is shown that the quantum fluctuations of the charge and current are related to not only circuit inherent parameter and coupled magnitude, but also quantum number of excitation, squeezed coefficients, squeezed angle and environmental temperature. And the quantum fluctuations increase with the increase of temperature and decay with time.
