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Two authentication schemes are proposed based on the unique behavior patterns of the smartphone users entering the authentication password and sliding the touch screen.The one class support vector machine(OCSVM) algorithm is applied to the authentication model,and the grid search algorithm is used to obtain the optimal parameters of the model.The experimental results show that the two authentication schemes have good generalization ability and verification accuracy,and the identity verification process will not interfere with the normal user operation.

The voltage problem caused by a large number of distributed generations connected to distribution network is attracting more and more attention. Aiming at the problem of voltage control in distribution network, this paper divides the operation state of distribution network into normal state, early warning state and emergency state. Under the principle of ensuring the voltage stability of distribution network firstly, and then making distributed generation with more generation as much as possible, the coordinated operation control strategy between distributed photovoltaic, small hydropower and energy storage under different operating states is proposed, and the effectiveness of the control strategy is verified by IEEE standard calculation example. The proposed method has important application value to ensure the reliable and stable operation of distribution network and distributed generation.

With the deepening of power market reform and energy conservation and emission reduction task, the carbon cost can be incorporated into the real-time trading decisionmaking of power market, which can further promote the lowcarbon development in China. In this paper, we firstly proposed low carbon electricity price mechanism (LCEP), which composed of spot market pricing, grid fees and RE surcharge. Then analysis model of generation side and demand side is constructed. Through detailed simulation calculation, the benefit effect of the proposed pricing mechanism is verified. The experimental results show that LCEP will be useful exploration for electricity market reform.

The energy routing system can use DC bus to connect multiple input and output converters. The structure of the system is complex, and the flow of energy is changeable. Therefore, a detailed and effective design is necessary. This paper takes impedance analysis method to analyze the smallsignal stability of the energy routing system which uses a DC bus structure with constant power load considering the droop control strategy of multiple converters. Firstly, a small-signal model is established for the converter module by combining control strategy. Secondly, based on the control of the bus side port voltage converter (BVCC) and the control of the bus side port current converter (BCCC) classification, derivation and summary of the application steps of unified impedance criterion in the energy routing system are obtained. Finally, the energy routing system under constant power load is simulated and analyzed. The result shows that the oscillation frequency at the time of system instability is consistent with the frequency of the intercept point of the impedance curve. Meanwhile, the increasing of the inductance value of the constant power load converter can improve the system stability. The result is identical to the theoretical analysis as well as verifying the applicability and accuracy of the unified impedance criterion applied in the energy router.

The coupling and complementary utilization of multiple energy sources is the basis of energy structure optimization, and the accommodation of renewable energy is the key issue in power system industry. In this paper, through the cooperation of gas turbine (GT) and power-to-gas (P2G) equipment, an integrated natural gas and electric power system (IGES) with bidirectional energy transmission is constructed. The gas turbine is used as the peak shaving unit of power system, and the excessive wind power is accommodated by P2G, which is converted into natural gas stored in gas storage tanks (GST). The contract model is proposed to regulate the natural gas in GST injected to pipeline network generated by P2G. Finally, the 14-bus natural gas system (NGS) and the IEEE-14-bus electric power system (EPS) are used to construct the IGES system with the mode of Electricity-Orientated. Aiming at the optimization of economy, by comparing the wind power accommodation in two scenarios, it shows that P2G can effectively accommodate wind power, and that injecting natural gas generated by P2G into gas network by contract can reduce the uncertainty of gas network dispatching.