A virtual power plant takes advantage of interactive communication and energy management systems to optimize and coordinate the dispatch of distributed generation, interruptible loads, energy storage systems and battery switch stations, so as to integrate them as an entity to exchange energy with the power market. This paper studies the optimal dispatch strategy of a virtual power plant, based on a unified electricity market combining day-ahead trading with real-time trading. The operation models of interruptible loads, energy storage systems and battery switch stations are specifically described in the paper. The virtual power plant applies an optimal dispatch strategy to earn the maximal expected profit under some fluctuating parameters, including market price, retail price and load demand. The presented model is a nonlinear mixed-integer programming with inter-temporal constraints and is solved by the fruit fly algorithm.

In power system control unicontrol with single storage units or centralized control with multiple storage units to meet different level targets is challenging. Considering the charge and discharge characteristics of storage devices, this paper proposes a hierarchical configuration structure of a battery and supercapacitor mixed storage scenario, and develops a convenient control method for accessing various DC loads and can central manage mass batteries in one place. Aiming at the optimal management of large scale battery storage, the paper proposes a three-layer battery hierarchical control structure and the control objects and control circuits are discussed. Simulation studies are used to verify the control effect of the hierarchical storage system and the results show that the strategy can effectively decrease photovoltaic output fluctuation.

The energy crisis has accelerated the rapid development of photovoltaic resources. However, the integration of large-scale photovoltaic (PV) systems into the power grid has significantly reduced system inertia, posing significant challenges to grid frequency stability. To enhance the frequency response characteristics of grid-connected PV systems, this paper proposes a rotor inertial power source (RIPS) control strategy for coordinated adjustable self-standby PV systems. First, based on the P-V operating characteristics of a PV system, a control strategy for estimating the maximum power of the PV system and implementing variable step size voltage control is proposed, enabling self-standby control for PV systems to provide primary frequency control capability. Second, by analyzing the transient response of the virtual synchronous generator (VSG) and leveraging its rotor operating characteristics, a RIPS control strategy is introduced to extract rotor inertial power, which increases the system’s inertia. Third, by utilizing the inertial power provided by RIPS in coordination with self-standby PV systems for grid connection, the inertia of the PV grid-connected system is effectively increased, thereby equivalently enhancing the frequency stability of the PV grid connection. The simulation results validate the effectiveness of the proposed control method, providing new insights for the expansion of PV system integration into the grid.

High photovoltaic penetration makes active distribution networks sensitive to voltage deviations, reverse power flow, and feeder operating stress. Energy storage converters can provide two complementary services: active power energy shifting and local, within-step reactive power support for voltage regulation. This paper develops a converter-aware multi-objective siting and sizing model in which installation buses, energy capacities, and PCS ratings are optimized jointly. The model explicitly represents the P-Q capability circle, voltage-droop reactive power command, reactive headroom, SOC limits, radial power flow, voltage deviation, and network loss; annualized cost and throughput-based degradation are retained as bounded planning terms rather than the sole design target. An adaptive multi-objective differential evolution (AMODE) algorithm solves the mixed discrete–continuous nonlinear problem using Latin hypercube initialization, adaptive mutation and crossover, hybrid mutation, an external archive, feasibility repair, and TOPSIS selection. IEEE33 and IEEE69 case studies are evaluated over thirty independent runs. In IEEE33, the selected plan raises the minimum voltage from 0.8866 to 0.9579 p.u. and reduces daily losses by 11.70%. The ablation study shows that removing PCS reactive support reduces the minimum voltage to 0.9190 p.u., demonstrating the technical role of converter-based Q support. The larger IEEE69 experiments further assess Pareto-front quality, feasibility, and statistical robustness. The hourly quasi-static formulation represents local converter action within each planning interval; it does not evaluate sub-second control or electromagnetic transients.

High penetration of converter-interfaced photovoltaic and wind generation reduces the effective inertia of islanded renewable energy systems and makes frequency stability more sensitive to load and renewable-power disturbances. This paper proposes a bounded adaptive droop framework for battery energy storage system (BESS) fast frequency response under low-inertia conditions, built around a bounded coordination mechanism. The framework coordinates frequency deviation, filtered rate of change of frequency (RoCoF), renewable-power fluctuation, and state of charge (SOC) to unify frequency-support capability with SOC availability and converter operating constraints. SOC-dependent available power limits, rated converter saturation, a ramp-rate limiter, RoCoF filtering, and measurement delay translate support demand into feasible power commands. A unit-consistent per-unit frequency-response model is combined with kW-level BESS power commands in MATLAB simulations. Compared with Fixed Droop, the proposed method reduces Max |Δf| and RMS Δf by 31.61% and 31.06%, respectively, on average across five deterministic cases, including four main disturbance cases and one charging case. In 30 Monte Carlo validation trials, the mean Max |Δf| decreases from 0.586 Hz to 0.330 Hz (43.66%), and the mean RMS Δf decreases from 0.416 Hz to 0.234 Hz (43.71%), with no SOC violation. Charging-protection tests further show that a fully charged BESS cannot absorb surplus renewable power, indicating the need for coordination with renewable curtailment, dump loads, secondary control, or reserve-SOC management.

The bidirectional ac/dc converter between the ac and dc subgrids plays a crucial role in enhancing the inertia support ability and ensuring the stable operation of the hybrid ac/dc distribution systems. In this paper, the bidirectional virtual inertia control strategy of hybrid distributed generations (DGs) integrated distribution systems is proposed for desired inertia support ability of both ac frequency and dc voltage. Firstly, the active power droop characteristics of the bidirectional ac/dc converter are analyzed, which reveals the steady power-sharing relationship between the ac and dc subgrids. Then, based on the dynamic power balance of the bidirectional ac/dc converter, the bidirectional virtual inertia control is proposed by introducing the virtual capacitor and moment of inertia, which can enhance the interactive inertia support ability of the hybrid distribution system. Finally, the effectiveness of the proposed control scheme is verified with a hybrid DGs integrated distribution simulation system in the PSCAD platform.