A technique based on reduction of order for solving ordinary differential equations is developed to find exact solutions for a generalized KdV-mKdV equation that possesses high order nonlinear terms. The analytical ex...A technique based on reduction of order for solving ordinary differential equations is developed to find exact solutions for a generalized KdV-mKdV equation that possesses high order nonlinear terms. The analytical expressions of several types of traveUing wave solutions for the equation are obtained in terms of sin, cos, tan, cot, sinh, cosh, tanh, coth and algebraic profiles. It is shown that the wave speed of travelling wave solutions and the coefficient of low order derivative term in the equation are two main factors to determine the change in the physical structures of solutions.展开更多
The bi-directional DC-DC converter(DDC)is commonly employed for a battery or supercapacitor(BA/SC)to accomplish power management flexibility.Current and voltage control for the DDC is crucial for power management.Focu...The bi-directional DC-DC converter(DDC)is commonly employed for a battery or supercapacitor(BA/SC)to accomplish power management flexibility.Current and voltage control for the DDC is crucial for power management.Focusing on control of the DDC,this paper first proposes a simple orderreduction control method for the first-order system,then applies the proposed control method to current and voltage control of the SC DDC.The effect of the inner current loop on the outer DC bus voltage loop is also analyzed.With the proposed simple order-reduction control method,the dynamic response of the SC DDC is obviously improved,and robustness to the SC voltage variation is achieved.The double-line-frequency ripple is also eliminated through the proposed simple and effective method.Finally,the effectiveness of the developed control algorithm is tested by the experiment.展开更多
基金The SWUFE’s Key Subject Construction Item Funds of the 211 Projectthe Scientific Research Foundation for Returned Scholars,Ministry of Education of China(No.200809011045)
文摘A technique based on reduction of order for solving ordinary differential equations is developed to find exact solutions for a generalized KdV-mKdV equation that possesses high order nonlinear terms. The analytical expressions of several types of traveUing wave solutions for the equation are obtained in terms of sin, cos, tan, cot, sinh, cosh, tanh, coth and algebraic profiles. It is shown that the wave speed of travelling wave solutions and the coefficient of low order derivative term in the equation are two main factors to determine the change in the physical structures of solutions.
基金supported in part by the National Natural Science Foundation of China under Grant 52007034.
文摘The bi-directional DC-DC converter(DDC)is commonly employed for a battery or supercapacitor(BA/SC)to accomplish power management flexibility.Current and voltage control for the DDC is crucial for power management.Focusing on control of the DDC,this paper first proposes a simple orderreduction control method for the first-order system,then applies the proposed control method to current and voltage control of the SC DDC.The effect of the inner current loop on the outer DC bus voltage loop is also analyzed.With the proposed simple order-reduction control method,the dynamic response of the SC DDC is obviously improved,and robustness to the SC voltage variation is achieved.The double-line-frequency ripple is also eliminated through the proposed simple and effective method.Finally,the effectiveness of the developed control algorithm is tested by the experiment.
