In this paper, the nonlinear waves and their barotropic stability in the tropical ocean and atmosphere are studied with the qualitative theory of the ordinary differential equation. The relationship is derived between...In this paper, the nonlinear waves and their barotropic stability in the tropical ocean and atmosphere are studied with the qualitative theory of the ordinary differential equation. The relationship is derived between the stability of nonlinear waves with different frequencies and the basic currents and their horizontal shear in the tropical ocean and atmosphere.展开更多
By using the second-order potential theory proposed by the author, in this paper it is investigated that nonlinear interaction of P- and SV- waves in isotropic elastic media. It is pointed out that if the angle betwee...By using the second-order potential theory proposed by the author, in this paper it is investigated that nonlinear interaction of P- and SV- waves in isotropic elastic media. It is pointed out that if the angle between the vectors of both waves is close to the 'splitting angle',the weak segment in media may be splitted out. When the frequencies of two primary waves are different, only sum-frequency component of the interacting wave can cause the phenomenon above mentioned.展开更多
针对电力系统的稳定性问题,设计了发电机励磁系统与可控串联补偿TCSC(thysistor controlled series compensation)装置的协调控制器。该方法从发电机励磁系统与TCSC模型出发,建立了含TCSC的单机无穷大系统的四阶非线性状态空间模型,利...针对电力系统的稳定性问题,设计了发电机励磁系统与可控串联补偿TCSC(thysistor controlled series compensation)装置的协调控制器。该方法从发电机励磁系统与TCSC模型出发,建立了含TCSC的单机无穷大系统的四阶非线性状态空间模型,利用非线性系统的微分几何理论,将其非线性模型精确线性化。在线性化模型的基础上,考虑电力系统运行参数的不确定性,采用滑模控制理论对发电机励磁系统与TCSC进行协调控制,通过指数趋近律和准滑动模态方法,最终获得了整个系统的滑模协调控制规律。单机无穷大电力系统仿真结果表明,所设计的协调控制方法对电力系统的扰动具有良好的适应性和鲁棒性,提高了电力系统的稳定性。展开更多
文摘In this paper, the nonlinear waves and their barotropic stability in the tropical ocean and atmosphere are studied with the qualitative theory of the ordinary differential equation. The relationship is derived between the stability of nonlinear waves with different frequencies and the basic currents and their horizontal shear in the tropical ocean and atmosphere.
文摘By using the second-order potential theory proposed by the author, in this paper it is investigated that nonlinear interaction of P- and SV- waves in isotropic elastic media. It is pointed out that if the angle between the vectors of both waves is close to the 'splitting angle',the weak segment in media may be splitted out. When the frequencies of two primary waves are different, only sum-frequency component of the interacting wave can cause the phenomenon above mentioned.
文摘针对电力系统的稳定性问题,设计了发电机励磁系统与可控串联补偿TCSC(thysistor controlled series compensation)装置的协调控制器。该方法从发电机励磁系统与TCSC模型出发,建立了含TCSC的单机无穷大系统的四阶非线性状态空间模型,利用非线性系统的微分几何理论,将其非线性模型精确线性化。在线性化模型的基础上,考虑电力系统运行参数的不确定性,采用滑模控制理论对发电机励磁系统与TCSC进行协调控制,通过指数趋近律和准滑动模态方法,最终获得了整个系统的滑模协调控制规律。单机无穷大电力系统仿真结果表明,所设计的协调控制方法对电力系统的扰动具有良好的适应性和鲁棒性,提高了电力系统的稳定性。
