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Integrating distributed generation (DG) into the main grid is a challenge for the safety and stability of the grid. The application of peer-to-peer (P2P) technology in microgrids with distributed generation is expected to facilitate increased self-consumption of distributed and renewable energy, and the rise of prosumers’ monetary benefits. A P2P energy trading model in microgrids with photovoltaic (PV) distributed generation and battery energy storage systems (BESSs) is proposed in this paper. We additionally designed a P2P electricity trading mechanism based on coalition game theory. A simulation framework of this model is presented which assumed a local community with 30 households under comprehensive constraints encompassing a customer load profile, PV system, BESSs, market signals including feed-in tariffs, and retail prices. Firstly, individual customers can post orders (purchasing orders or selling orders) and exchange information in a P2P energy trading market. Secondly, the microgrid operator can validate the orders based on how to achieve the minimum overall energy consumption in microgrids and set reasonable real-time purchasing and selling prices for P2P energy transactions. Thirdly, the orders can be automatically conducted and completed at the designed optimal price. This mechanism can be a practical solution motivating individual customers to participate in P2P electricity trading, assist with electricity cost reduction, benefit from electricity supply increases, and help the grid operators to make the most economically and socially friendly decisions.

This paper deals with a sliding mode control for a class of fractional uncertain chaotic systems under perturbations of parameters. A fractional integral sliding surface is proposed for fractional-order systems and then the sliding mode control technique is carried out to realize the control of the given systems. Based on Lyapunov stability theory, we theoretically verify that the controller is effective, and the designed control scheme can go against the system’s uncertainty to guarantee the property of asymptotical stability in the presence of parameter fluctuations. Later, two typical examples are illustrated numerically to show that the control approach in this paper is capable for any form of fractional-order uncertain systems.

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For the case of unbalanced grid voltages, active power of PWM rectifier is reduced due to the current limitation of power switches. Under unbalanced grid voltages, two existing control methods for the PWM rectifier are widely adopted, one for instantaneous active power control, and the other for balanced positive sequence current control. To maximize the PWM rectifier instantaneous active power capability and minimize active power oscillations during voltage dips, a control method combining balanced positive sequence and instantaneous active power control is proposed. The limitations of these two control methods are given, and the fluctuations on active and reactive power using the proposed control method are discussed in detail in this paper. The analysis in this paper is based on p.u. system, and some conclusions are drawn. Corroboration of the expected features of the proposed control method is carried out by means of experiments.