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Electric vehicles (EVs) are flexible demand-side response resources in a power distribution system. Reasonable and orderly control of charging/discharging processes of aggregated EVs can improve their coordination and interaction with the distribution system and ensure its efficient and stable operation. Aiming at the problem that the fluctuation of wind power output may affect the stable operation of distribution system, a real-time control strategy for aggregated EVs to smooth the fluctuation of wind power is proposed. Firstly, considering the dispatchability of EVs, the charging/discharging energy boundary model is established to determine the charging/discharging margin of an EV at each moment. Then, first-order low-pass filtering is used to determine the total dispatching power of aggregated EVs. Finally, the total charging power of aggregated EVs is determined and power allocation is carried out. Simulation results show that the proposed strategy can achieve real-time smoothing for the fluctuation of wind power output while meeting the charging requirements of EVs, and the proposed strategy can not only reduce the fluctuation rate of total load, but also realize peak shaving and valley filling for the distribution system.Energies 2020, 13, 757 2 of 21Energies 2020, 13, 757 3 of 21 charging power of each EV by maximizing the total charging/discharging margin of the aggregated EVs at the following moment, and converts the problem into a mixed-integer linear programming (MILP) problem by using the piecewise linearization method, which improves the solution efficiency. The Control Framework of Aggregated Electric Vehicles (EVs) Participating in Power Grid SchedulingThe output power of a wind farm fluctuates due to the uncertainty and intermittence of wind, and the wakes between wind turbine units. Large-scale wind power integration may cause load fluctuation and affect the stable operation of the power system. As a flexible decentralized dispatchable unit, EVs can coordinate and complement wind power under certain conditions. The coordinated management of aggregated EVs with effective control strategies can smooth the load curve, promote wind-power accommodation, and ensure the safe and reliable operation of the power system [18].The real-time control framework of aggregated EVs participating in power grid scheduling is shown in Figure 1. All charging piles in the figure are direct current (DC) charging piles whose charging and discharging power can be adjusted continuously between 0 and the maximum [19,20]. At the same time, this kind of charging pile has the function of reading information, such as the time when the EV is connected to the charging pile (on-grid time), the time when the EV leaves the charging pile (off-grid time), and the battery level of the EV, etc. It can also perform information exchange with the aggregator management center (AMC) through the low-voltage carrier communication module. The AMC can model the charging process of the aggregator and send the state information of the aggregator t...

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Aiming at the optimal configuration of a regional integrated energy system (IES), this paper proposes an energy-conversion interface (ECI) model that simplifies the complex multienergy network into a multi-input–multioutput dual-port network, consequently achieving the energy-coupling relationship between the energy-supply side and the demand side. An optimized configuration model of the ECI was constructed by considering economic performance, such as device-installation cost, operation and maintenance cost, and environmental cost, as well as energy-saving performance, such as energy-utilization efficiency. Then, the ECI optimal-configuration model was established by taking a campus in northern China as an example. To verify the validity of the model, device planning quantity and daily energy scheduling of the integrated energy system of the campus were obtained by solving the model with the particle-swarm optimization method. Finally, sensitivity analysis of the system to energy prices and the reweight approach for the targets are also given in this paper, providing a decision-making basis for system planning.

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