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This paper addresses the Hamiltonian mathematical modeling and dynamic analysis of a hydro-energy generation system in the transient of sudden load increasing. First, six dynamic transfer coefficients of the hydro-turbine for the transient of sudden load increasing are innovatively introduced into the hydro-energy generation system. Considering the elastic water-hammer model of the penstock and third-order model of the generator, we established a dynamic mathematical model of the hydro-energy generation system in the transient of sudden load increasing. Moreover, from the point of view of the transmission and dissipation of energy of the system, we propose the hydro-energy generation system into the theory frame of the generalized Hamiltonian system. A novel Hamiltonian model of the hydro-energy generation system is established utilizing the method of orthogonal decomposition. Finally, based on the data of a real hydropower plant, numerical simulations and

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Insulation assessment of HV cables requires continuous partial discharge (PD) monitoring to identify the nature of insulation defects and to determine any degradation trends. However to recover PD signals with sufficient sensitivity to determine such insulation degradation in substations with high levels of electromagnetic interference is a major challenge. This paper is the second of two papers addressing this challenge for on-line PD measurements in a noisy environment. The first paper described a wavelet transform-based method of interference rejection. This paper applies that method to the problem of on-site testing, using both laboratory tests and onsite tests. The laboratory tests were used to stimulate the noisy on-site testing environment, with use of transient pulse-like noise, discrete spectral interference (DSI) and white noise. These noise types have been successfully rejected by the method proposed in the first paper. In addition, on-site tests have been undertaken and have been able to detect PD signals in an old 11 kV substation multicable installation.Index Terms -partial discharge, wavelet transforms, cables, interference suppression, on line measurement.

In order to study the nonlinear dynamic behaviors of a hydro-turbine governing system in the process of sudden load increase transient, we establish a novel nonlinear dynamic model of the hydro-turbine governing system which considers the elastic water-hammer model of the penstock and the second-order model of the generator. The six nonlinear dynamic transfer coefficients of the hydro-turbine are innovatively proposed by utilizing internal characteristics and analyzing the change laws of the characteristic parameters of the hydro-turbine governing system.