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Variations in state-of-charges (SOCs) of batteries in a cascaded H-bridge multilevel converter (CHB-MLC) based battery storage system (BSS) could lead to undesired efficiency and performance drops, even failure of the whole system. Hence, SOC balancing is crucial for BSSs. Avoiding over-modulation region, ensuring zero common-mode voltage and reaching balanced SOC condition as quickly as possible are the key points to consider while performing SOC balancing. In this paper, a gain-scheduling based adaptive SOC balancing method is proposed for single-phase CHB-MLC based BSSs. In the proposed method, gains of the proportional controllers are updated at each sampling time based on the mathematical relationship between instantaneous SOCs and voltage reference of the CHB-MLC. Performance of the proposed method is validated through a Monte Carlo simulation based numerical analysis and experimental studies on a single-phase three-module CHB-MLC based BSS. Results reveal that the proposed method achieves SOC balancing at least two times faster than the traditional constant gain methods while avoiding over-modulation region and having zero common-mode voltage. • Over-modulation region is avoided for all instantaneous SOC conditions. • Zero CM voltage throughout the SOC balancing operation is ensured. • SOC balancing speed is increased at least two times compared to traditional methods. • Battery capacity losses are reduced at least 40 % compared to traditional methods. • SOC balancing speed and battery capacity losses are verified by Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

This work is interested in the study and analysis of the functioning of a hybrid energy production system made up of three energy sources: Wind energy, a photovoltaic generator, and a battery. The control of each part of the multi-source production chain generates the optimization of the functioning of the global system. The multi-level inverter is inserted in the chain of the hybrid system which can also improve the quality of the energy injected into the alternating load and consequently reduce the harmonic rate. The stability of the voltage across the DC bus capacitor plays a very important role in the healthy functioning of the production chain. For this purpose, an adjustment based on a sliding mode controller which ensures the adjustment of the DC voltage. Among the solutions deployed in order to obtain an excellent quality of energy to the network or to the AC load is the use of multi-level inverters. The major interest of this work is to extract the maximum power from the DC bus based on fuzzy logic control. The load requirements are often varied and to meet them, an algorithm for managing the energy flow between the different production sources is proposed. The implementation of the proposed system is carried out under the Matlab / Simulink environment, the results obtained validate the effectiveness of the technique and its feasibility in simulation and even in the case of practical implementation in real time. [ABSTRACT FROM AUTHOR]

Abstract In this paper, an optimal energy management model of a 2 kW residential grid-interactive Wind Energy Conversion System with battery storage is presented. For this purpose, a mathematical model describing the system's optimal operation is developed. Thereafter, the performance of the developed model is analyzed in the South African context using Matlab. For the selected residential case study, the simulation results have shown that up to 95% daily operation cost reduction is achievable. [ABSTRACT FROM AUTHOR]

Microgrids contain various power systems with different power capacities and generation fluctuations. An overall power management strategy is necessary to manage power flows among all interconnected elements. This paper presents a multi –agent system solution to energy management in a microgrid based on distributed hybrid renewable energy generation and distributed consumption (vital loads and non-sensitive loads). The real model of each element connected is needed, enabling microgrid modeling and control. A new architecture using multi –agent system solution is proposed, allowing making all the calculations required in Matlab Simulink and the intelligent strategy of energy management is executed by agents designed by Jade. While the communication middleware between Jade and Simulink is carried out by MacsimJX. Finally, it was justified how multi agent system can be a suitable solution to microgrid implementation requirements. [ABSTRACT FROM AUTHOR]

The increasing distributed generation of renewable energies in distribution networks leads to several challenges for distribution network operators (DNOs). During high feed-in times, voltage violations can occur if the hosting capacity of the grid for distributed generation is exceeded. The paper at hand investigates the installation of grid-supporting battery storage system (BSS) in the medium voltage (MV) level to serve mainly for voltage compliance and to defer grid reinforcement. A control approach for the BSS based on two characteristic curves is suggested. The BSS is then analyzed technically and economically for scenarios of high distributed generation. The results show that the alternative of BSS has potential to defer grid reinforcement in the presented case studies. However, the power curtailment is more viable than the BSS and grid reinforcement. The economic viability of BSS can increase in the future based on the expected reduction of battery costs. Furthermore, BSS have the technical potential for providing other services, since voltage violations occur during high feed-in times. [ABSTRACT FROM AUTHOR]

• Multi-objective optimization for smart distribution is proposed. • Operation cost and energy loss are simultaneously minimized. • Both active and reactive power from battery storage systems is considered. • Problem is modelled as mixed integer second order cone programming. The smart distribution system (SDS) will transform the energy sector into a new era of increased flexibility, sustainability, reliability, and efficiency that will contribute to environmental and economic health. However, a proper scheduling strategy with strategic goals is needed to reap these benefits of SDS. In this regard, a multi-objective techno-economic optimization framework for optimal operation of SDS consisting of different resources such as renewables, dispatchable distributed generations and battery storage systems (BSSs) is presented in this paper. The proposed framework aims at simultaneously minimizing operation cost and network energy loss. To manage the operation of grid effectively, provision of both real and reactive power from BSS is included in operation of SDS. The initial operational problem is modeled as mixed integer non-linear non-convex optimization, which is then translated into mixed integer second order cone programming that can be successfully solved using commercially available solvers. Moreover, the multi-objective problem is tackled using ϵ -constraint method followed by fuzzy satisfying criteria. In order to highlight the efficacy of proposed work, case studies are conducted on 33-bus distribution system. Results demonstrate that utilization of reactive power services from BSS significantly reduces energy losses and operation cost. [ABSTRACT FROM AUTHOR]