The intermittence of high proportion of renewable energy further aggravates the insecure operation of power system, which makes flexible resources configuration more critical. Therefore, it is necessary to conduct research on flexible resources planning and configuration of power system. For the multi-energy microgrid, a bi-level collaborative optimization method of configuration and operation of flexible resources is proposed in this paper, considering the characteristics of storage battery and power to hydrogen (P2H) equipment. Taking the minimum total annual carbon emissions and the maximum comprehensive annual profit as the objective functions for the outer layer model, and choosing maximum daily operating profit for the inner layer model, a case study under electricity-hydrogen load is carried out. Then cost reduction scenarios of these two flexibility technologies is depicted, and economic, cleanliness and flexibility indices are designed to compare and evaluate the competitiveness of the two technologies in different conditions. The results show that the proposed optimal configuration method can prominently improve the environmental benefits of the microgrid with less economic cost. At present, compared with P2H technology, storage battery technology has overwhelming advantages, but the former will have greater profit margins and market potential in the future.

Increasing the permeability of distributed energy results in a greater number of complex problems related to voltage quality, safety, and stability in distribution networks. Achieving a single optimal configuration of reactive power or energy storage to satisfy the increasingly diverse requirements of modern power grids is difficult. In this study, a configuration strategy that combines energy storage and reactive power is proposed to meet the requirements of new energy distribution networks in both active-power regulation and reactive-power compensation. The strategy also realizes a balanced optimization of flexibility, voltage quality, and economy, and adapts to the influence of new energy under different permeabilities. First, a safety and stability evaluation system of the distribution network is established based on flexibility and reactive-power demands. Second, based on the coupling between the planning and operating layers, a two-layer model of optimal energy-reactive power allocation in the distribution network is established. A small-probability random mutation method is then used to improve the standard particle swarm optimization algorithm to reduce the possibility of falling into local optima. Finally, an improved IEEE-33 node distribution system is used in a simulation test to verify the rationality and effectiveness of the scheme. Simulation results show that the proposed scheme can effectively improve the economy, security, and stability of the distribution network, and a multi-objective optimal configuration scheme can be obtained under new energy permeabilities.

At present, the transmission grid with a high proportion of photovoltaic and wind power has a generally high rate of curtailment of wind and solar power. As a potential utility, the configuration of energy storage equipment is favored in current research. Aiming at the problem of energy storage configuration in the transmission network, this paper proposes a configuration method based on a two-layer programming model for the hydrogen-electric hybrid energy storage system in order to reduce the comprehensive cost and the curtailment rate of wind and solar energy. Firstly, the characteristics of the hydrogen-electricity hybrid energy storage system are modeled, and on this basis, a two-layer planning model for the power and capacity allocation of the hydrogen-electricity hybrid energy storage system in the transmission network is established. The upper-layer model aims to minimize the annual comprehensive cost after the energy storage is configured; the lower-layer model aims to minimize the curtailment rate of wind and solar energy. Then, according to the different characteristics of batteries and hydrogen energy storage, a hydrogen-electricity hybrid energy storage system coordination strategy is proposed. Finally, according to the nonlinear multi-objective characteristics of the model, the two-layer iterative particle swarm optimization algorithm is combined with power flow calculation to solve the model. In the simulation part, taking a transmission network with a high proportion of wind and solar power access as an example, the capacity and location of hydrogen-electricity hybrid energy storage system are optimized to verify the feasibility and effectiveness of the model and the proposed solution algorithm. Ultimately, the transfer ability of photovoltaic and wind power output in time series is improved, the consumption of high-carbon fossil energy is reduced, and the curtailment rate of wind and solar energy is reduced.

According to the complementary characteristics of electrochemical energy storage and hydrogen storage, an integrated optimization model for the configuration and operation of a hybrid energy storage system is given, including electrochemical energy storage, hydrogen storage proposed and an intelligent algorithm. The model is based on a two-layer decision optimization problem, in which two different time dimensions of the hybrid energy storage system configuration and operation are solved in upper and lower layers, and the interaction between them is considered. A reinforcement learning proximal policy optimization (PPO) algorithm is used to solve the two-layer optimization model. By comparing the results of applying various traditional algorithms to solve the scenery data of a region in Gansu Province, it is verified that the used algorithm has the highest adaptability and the fastest convergence speed in a complex environment. The results show that the application of this model can reduce the abandoning rate of wind and solar power by 24% and effectively improve the comprehensive benefit of the system, and that hydrogen storage as a capacity-based energy storage configuration is not limited by topographical factors and is suitable for diverse application scenarios, thus providing an application demonstration for the widespread deployment of hydrogen storage, a new form of energy storage, in the whole country.