The existence and representation of the exact solution are given for a nonlinear functional equation in the reproducing kernel space. For a numerical computation, we present a large-range convergence iterative method ...The existence and representation of the exact solution are given for a nonlinear functional equation in the reproducing kernel space. For a numerical computation, we present a large-range convergence iterative method for solving the nonlinear functional equation. In the iterative method, the convergent condition is simple and the convergence is irrespective to the choice of the initial function. It is worthy to note that the presented method can be generalized to solve other nonlinear operator equations.展开更多
Overmodulation is frequently required during the transient interval at high speed operations of IPMSMs （interior permanent magnet synchronous motors）. In this work, an overmodulation method is developed in the synch...Overmodulation is frequently required during the transient interval at high speed operations of IPMSMs （interior permanent magnet synchronous motors）. In this work, an overmodulation method is developed in the synchronous reference frame with a provision of assigning different priorities to d- and q-axes currents. During the current boosting in motoring, the d-axis current is increased by priority for a fast current response, and to minimize the overmodulation period. However in the regeneration process, the q-axis current is decreased by priority during a load reduction. Simulation and experimental results show that the proposed method, compared with the existing minimum-phase error method, is better for a fast current response, and in shortening the overmodulation period.展开更多
With the integration of renewable power and electric vehicle,the power system stability is of increasing concern because the active power generated by the renewable energy and absorbed by the electric vehicle vary ran...With the integration of renewable power and electric vehicle,the power system stability is of increasing concern because the active power generated by the renewable energy and absorbed by the electric vehicle vary randomly.Based on the deterministic differential equation model,the nonlinear and linear stochastic differential equation models of power system under Gauss type random excitation are proposed in this paper.The angle curves under different random excitations were simulated using Euler-Maruyama(EM) numerical method.The numerical stability of EM method was proved.The mean stability and mean square stability of the power system under Gauss type of random small excitation were verified theoretically and illustrated with simulation sample.展开更多
基金Sponsored by the Education Department Science and Technology Foundation of Heilongjiang Province (Grant No.11531324)
文摘The existence and representation of the exact solution are given for a nonlinear functional equation in the reproducing kernel space. For a numerical computation, we present a large-range convergence iterative method for solving the nonlinear functional equation. In the iterative method, the convergent condition is simple and the convergence is irrespective to the choice of the initial function. It is worthy to note that the presented method can be generalized to solve other nonlinear operator equations.
文摘Overmodulation is frequently required during the transient interval at high speed operations of IPMSMs （interior permanent magnet synchronous motors）. In this work, an overmodulation method is developed in the synchronous reference frame with a provision of assigning different priorities to d- and q-axes currents. During the current boosting in motoring, the d-axis current is increased by priority for a fast current response, and to minimize the overmodulation period. However in the regeneration process, the q-axis current is decreased by priority during a load reduction. Simulation and experimental results show that the proposed method, compared with the existing minimum-phase error method, is better for a fast current response, and in shortening the overmodulation period.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51137002,51190102)the Fundamental Research Funds for the Central Universities (Grant No. BZX/09B101-32)
文摘With the integration of renewable power and electric vehicle,the power system stability is of increasing concern because the active power generated by the renewable energy and absorbed by the electric vehicle vary randomly.Based on the deterministic differential equation model,the nonlinear and linear stochastic differential equation models of power system under Gauss type random excitation are proposed in this paper.The angle curves under different random excitations were simulated using Euler-Maruyama(EM) numerical method.The numerical stability of EM method was proved.The mean stability and mean square stability of the power system under Gauss type of random small excitation were verified theoretically and illustrated with simulation sample.
