Due to the popularity of plug-in electric vehicles (PEV)and the development of converter technology, the electric-drive-reconstructed onboard converter(EDROC)is widely used in the charging system which can work in vehicle to grid(V2G) mode or grid to vehicle(G2V) mode. In this paper, an EDROC for V2G/G2V energy management system is proposed. The EDROC uses permanent magnet synchronous motor as a charging inductor in V2G/G2V mode without additional equipment. Meanwhile, this paper proposes a hierarchical V2G/G2V energy management system and the corresponding hierarchical control strategy with the proposed EDROC. This system can realize the energy distribution between PEVs, and avoid PEV overcharging. The proposed EDROC and control strategy are verified by simulation and experiment.

With the high penetration of wind power, the power system has put forward technical requirements for the frequency regulation capability of wind farms. Due to the energy storage system’s fast response and flexible control characteristics, the synergistic participation of wind power and energy storage in frequency regulation is valuable for research. This paper established a frequency characteristic model of a power system, including wind power and energy storage, and analyzed the influence of different frequency regulation methods on system stability. Based on the established model, a fuzzy PID-based energy management strategy was designed for different disturbance scenarios, which offered the advantages of simple parameter design and easy online operation of the project. This paper used a case based on the actual parameters for verification. The energy storage, rated at 10% of the wind farm’s rated power, provided 56% frequency drop suppression and 89% frequency fluctuation rate suppression, according to the proposed model in this paper. The proposed fuzzy PID control strategy achieved adaptive control of the controller parameters under strong disturbances and was able to provide an additional frequency rejection capability of 10–25%.

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With the development of the global economy and the increase in environmental awareness, energy technology in transportation, especially the application of energy storage technology in rail transportation, has become a key area of research. Rail transportation systems are characterized by high energy consumption and poor power quality due to the more flexible regulation capability of energy storage technology in these aspects. This paper summarizes the latest research results on energy storage in rail transportation systems, matches the characteristics of energy storage technologies with the energy storage needs of rail transportation, and analyzes the operation of energy storage systems in different scenarios. The adaptability of batteries, supercapacitors, and flywheels as energy storage systems for rail transportation is summarized and compared. The topologies and integration methods of various energy storage systems are studied. The control strategies under each control of rail transportation are summarized and proposed. The future development direction of energy storage system for rail transportation prospects and the corresponding reference is provided for the engineering of energy storage technology in the field of rail transportation.