Development of vacuum and SF₆-alternative gas circuit breakers with higher capacity and reliability requires fundamental understanding of the arc plasmas, which is achieved by systematic diagnoses. This article provides recent trend in diagnostic technology, particularly focusing on the number densities in the arc plasma.

The increasing penetration of renewable generation presents challenges to maintaining the supply-demand balance in power systems. Consequently, energy storage units will be a critical source of flexibility, particularly through the dispatch of primary frequency control (PFC). However, without an appropriate energy regulation strategy, the activation of PFC may be truncated due to intrinsic energy constraints, effectively reducing the available reserve power for frequency support. To address this limitation, this paper proposes a coordinated control strategy based on state-of-charge (SoC) balancing for a fleet of distributed energy storage units. The proposed control law introduces an energy-sharing droop gain and SoC equalization power term as complementary mechanisms to steer the units towards a common target SoC value. Since both mechanisms depend on information aggregated from all storage units, a peer-to-peer communication network is assumed to enable the implementation of distributed consensus-based algorithms. Simulation results demonstrate that the proposed strategy enhances energy utilization across the storage fleet, thereby extending the PFC activation and unlocking the full power capacity for frequency control.

This paper proposes a novel coordinated control method, termed “H2-Assisted Control”, and an operation planning approach to enhance the power supply and demand adjustment capability of a hybrid system composed of battery storage and water electrolyzer. The H2-Assisted Control facilitates power exchange between the battery storage and the electrolyzer, ensuring sufficient charge/discharge margin of the battery required for power supply and demand adjustment. Based on this control method, a mathematical optimization model for operation planning is developed, which considers the charge/discharge margin requirements of the battery storage and shifts part of these requirements to hydrogen storage. Simulation results validate that the proposed plan can be effectively executed using the H2-Assisted Control and demonstrate an increase in feasible adjustment capacity (ΔkW), thereby leading to improved operational profit.

The Editorial Committee is working on planning and editing the publication of Power and Energy Society. In this article, the committee's activities of the last term are reported, and recent trends and future problems are also discussed. The process of planning and editing the publication and the challenges of reducing the necessary months for reviewing papers and increasing the number of submitted papers are shown.