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In the new round of electricity marketization reform, the opening up of the sales side market marks that the operation mode of China’s power market has started the transformation from wholesale competition mode to retail competition mode, and also means that the competition risks that were borne by the generation side alone in the past transaction process now need to be shared by the sales side. With the aggravation of market competition in power selling side, the risk of profit loss of power selling companies is becoming increasingly prominent in medium and long-term trading. On the basis of considering the different scenarios such as the annual long-term alliance and clean energy market, aiming at the risk factors such as collusion of power generation companies, instability of clean energy power generation output and uncertainty of actual electricity demand of users, the risk degree is determined by conditional value at risk method, the design of risk aversion factor is proposed, and the risk aversion model of profit loss of multi types of power sales companies is constructed, and the decision of avoiding is given.

Microgrids have become an attractive option for distributed generation (DG) with increase in renewable energy sources (RES) and storage systems. The existence of both AC and DC microgrids has led to a new concept of hybrid AC/DC microgrid which consists of both AC and DC grids tied by an interlinking converter (ILC). Such hybrid AC/DC microgrid has the advantages of both AC and DC with increased efficiency and less cost since the conversion between AC and DC is reduced. The management of power in such a grid becomes important for voltage and frequency control. Different voltage and frequency control strategies have been successfully implemented within AC and DC grids, but the control of hybrid microgrid requires further attention with focus on ILC. This study presents an overview of various control schemes used for voltage and frequency regulation in standalone and transition mode operation of hybrid microgrid. A detailed study on hybrid grid structure is presented with different modes of operation. Various ILC strategies based on droop and communication-based control are presented. Based on the analysis, some recommendations are presented for future research.