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For quantitative analysis of impact of grounding capacitance on the traction power supply system, in this paper, two wires system as an example with the mirror image method concluded the calculation formula of two wires system to ground capacitance and partial capacitance. At last, the influence of grounding capacitance on the traction power supply system is given quantitatively to provide the more accurate basis for engineering calculation.

In this paper, power characteristics of hybrid wind, photovoltaic generation and energy storage device is studied. Two-stage Smooth Energy Storage Control Strategy is designed in order to effectively inhabit both high frequency and low frequency section of wind and photovoltaic power. A topology of demonstration project of hybrid wind power, photovoltaic, energy storage and power transmission in north China is considered for simulation. Power characteristic of different hybrid generation mode is studied, and the simulation results show reliability and effectiveness of the control strategy. The results studied have the important significance for grid planning and operation.

The output power of wind farms has significant randomness and variability, which results in adverse impacts on power system frequency stability. This paper extracts wind power fluctuation feature with the HHT (Hilbert-Huang Transform) method. Firstly, the original wind power data was decomposed into several IMFs (Intrinsic Mode Functions) and a tendency component by using the EMD (Empirical Mode Decomposition) method. Secondly, the instantaneous frequency of each IMF was calculated. On this basis, taking a WSCC 9-bus power system as benchmark, the impact on power system frequency caused by wind power fluctuation was simulated in a real-time simulation platform, and the key component which results in the frequency deviation was found. The simulation results validate the wind power fluctuation impacts on frequency deviation, underlying the following study on power system frequency stability under the situation of large-scale intermittent generation access into the grid.

Generator terminal supplement damping control (GTSDC) is an effective method to damp the sub-synchronous resonance. In this paper, the real time closed loop testing technique of GTSDC is studied. The four kind of performance test is discussed. They are characteristic valuation of GTSDC, model contrast of GTSDC and real-time digital simulation (RTDS), GTSDC coordination with the excitation damping control, and robustness analysis of GTSDC. The testing results show that the real time closed loop testing technique of GTSDC is effective and reliable.

In this paper, the wind resources and planning in Jing-jin-tang grid are firstly introduced. The focus is on the analysis of characteristics of wind power output in Jing-jin-tang grid. The analysis data is from the actual wind running power and load in the whole year. The indicators considered are wind power penetration, proportion of wind output power, guaranteed capacity, effective output, etc. The results studied have the important significance for grid planning and operation.

The increasing size of wind power generation requires considering wind farm model in power system stability analysis. Nowadays, the most widely used wind turbine type is doubly-fed induction generator, which is concerned here. The wind farm detailed model including every individual DFIG is high-dimensional and costs a lot of computation time, thus wind farm equivalent model is required. This paper presents an eigen analysis based approach to settle wind farm equivalent modeling for power system simulation. Simulation results indicate the equivalent model has good accuracy, and can reflect wind farm features, which is proper for large-scale power system simulation.

This paper presents a decentralized adaptive backstepping controller to dampen oscillations and improve the transient stability to parametric uncertainties in multimachine power systems. The proposed design on the i th synchronous generator uses only local information and operates without the need for remote signals from the other generators. The design of the nonlinear controller is based on a modified fourth-order nonlinear model of a synchronous generator, and the automatic voltage regulator model is considered so as to decrease the steady state voltage error. The construction of both the control law and the associated Lyapunov function is systematically designed within the design methodology. A 3-machine power system is used to demonstrate the effectiveness of the proposed controller over two other controllers, namely a conventional damping controller (power system stabilizer) and one designed using the feedback linearization techniques.

This paper scrutinized the damping effects of installing the prototype PSSs by a transient analysis for eight buses of faults in the South Korean power system. The PSSs used have the ω-PSS blocks for IEEEST model with a single input and the ω+power PSS blocks for PSS2A model with dual inputs. The simulation tool was a TSAT (Transient Security Assessment Tool) developed by Powertech Labs Inc. The voltages of the transmission line for simulations were 765㎸ and 345㎸, and the faults for eight cases were sequenced by considering the open state and the close state of the lines. In the simulations, the three-phase line to ground (L-G) fault generated different points for each region. The simulations were compared to the cases of no PSS, partial IEEEST and PSS2A, absolute IEEEST, and absolute PSS2A to show that the power system oscillation can be effectively damped by PSS modules. Simulations were conducted to confirm the effectiveness for the KEPCO (Korea Electric Power Corporation) power system.

In this paper the analysis of small signal stability of grid-connected doubly fed induction generators (DFIG) is presented. The detailed model of grid-connected DFIG wind turbine is firstly established, and the eigenvalues are classified and characterized based on participation factors. Then the modal analysis including its converter and pitch controllers is studied, and model simplification of the DFIG wind turbine is presented under the acceptable assumption. Finally, simplified model of DFIG wind turbine is used in dynamic analysis of Zhangjiakou wind plant in China, and the results offer a good dynamic performance.

This paper proposes a nonlinear adaptive back-stepping controller to damp the oscillations and improve the transient stability in multi-machine power systems. The designed controller is adaptive to unknown generator parameters. The proposed controller is designed based on a fourth order nonlinear model of a synchronous generator and the automatic voltage regulator model is considered so as to decrease the steady state voltage error. The construction of both control law and associated Lyapunov function is consistently systematic within the design methodology. A 3-machine power system is used to demonstrate the effectiveness of the proposed controller over other two controllers: one is the conventional damping controller (power system stabilizer) and the other is the one designed by the feedback linearization technique.

In this paper, we propose a nonlinear back-stepping controller (NBC) to damp the generator oscillations and improve the transient stability in multi-machine power systems. An observer is designed to estimate the inaccessible states, which is different from previous back-stepping designs with complete states of the whole system. Moreover, in order to counteract the destabilizing effect of the observer errors, observation errors are treated as disturbances and accounted for using nonlinear damping term. Different from other back-stepping controller design in power system before, the proposed controller is designed on a reduced forth order nonlinear model of a synchronous generator with which the voltage error of steady state is decreased. The stability of the system is verified by Lyapunov methods. The 3-machine power system is applied to demonstrate the effectiveness of the proposed controller over tuned power system stabilizers.