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For hybrid energy systems utilizing renewable energy sources such as the power grid of Phu Quy island - Binh Thuan province, the integration of battery energy storage system (BESS) could be seen as a practical solution with remarkable advantages including economic and technical preeminence. BESS contributes to increasing renewable energy penetration, enhancing system stability and reducing the dependence on fossil fuel generation. However, the integration of BESS into an existing hybrid power system also necessitates to conduct a quantitative analysis of the performance of different solutions. This study investigates operational data of Phu Quy power grid for one year, evaluates solar energy potential and proposes a proper BESS integration solution based on a careful quantitative analysis. The simulation results show that selection of larger BESS capacity increases penetration rate of renewable energy. Nevertheless, of all proposed BESS integrated scenarios, renewable energy penetration rate as well as diesel consumption do not show a major difference. Therefore, choosing BESS also needs to consider the load capacity and time required to start and interconnect standby diesel generators.

Currently, electrification of mobility could be considered as a sustainable solution for reducing oil dependency and encouraging environmental protection. In Vietnam, socioeconomic condition, current traffic infrastructure and users’ habit are main causes of the prevalence of motorcycles, especially in large urbans. A huge number and high density of personal gasoline-powered vehicles has pressured traffic infrastructure and this is claimed to be the major contributor to air pollution. With reasonable purchase price and low operation cost, electric two-wheelers (e-bikes, electric mopeds, electric motorcycles) could be seen as a promising solution for replacing gasoline-powered motorcycles. In order to promote this transition, supporting infrastructure such as charging facilities should be studied, investigated and deployed. Nevertheless, electrification of mobility is only beneficial to environment if the electricity used to charge EVs comes from renewable sources and not from fossil fuel generation. With high potential of solar energy, local consumption of PV generation for charging stations in Vietnam may provides a promising solution. This paper aims to research the trend of transport electrification and the feasibility of PV-integrated charging stations for electric two-wheelers in Vietnam as well as propose PV-based charging station solution at Electric Power University.

In a VSC-HVDC link, a DC fault can lead to destructive overvoltage or overcurrent in DC lines, thus DC protection system plays an essential role for isolating the fault section of the network. This paper presents a combined protection scheme of multi-terminal VSC-HVDC links under DC faults. This scheme uses DC breakers and inductors to limit overcurrent in DC links under DC faults. Simulation results realize the presented method.

With the strong development of renewable energy sources, the next generation network could include an existing AC system and multi-terminal VSC-HVDC links. In such an AC-DC network, interactions between AC and DC side under faults are interested to study. This paper presents a dedicated model of a sample AC-DC network and analyzes transient responses of this network following faults.

Integration of wind and solar within dc microgrids into buildings is presented. First, a cache control method is applied to utilize a hybrid energy storage which combines diverse but complementary storage technologies. Second, an adaptive droop scheme is proposed to provide coordination control of a battery in real-time and long-term operation. Compared with other existing droop controls, it is distinguished in that the adaptive droop is proposed to force real-time state of charge of battery to track on the optimized scheduled SOC in long-term. Several simulations are performed to realize the presented method.

This paper presents and analyses a represented ac system with an overlay HVDC network based on multi-terminal VSC. A state space representation and a method of the automatic development of the small signal model of the hybrid ac/dc system is achieved. The methodology to develop the small signal model is composed of four steps being construction of sub system units; development of state space models for each unit; linearization of nonlinear models and integration of all linearized models. The control architecture schemes for VSC systems are also presented in order to obtain control objectives such as control active and reactive power, and dc voltages. Based on the developed platform, the small signal stability is analyzed to investigate the effect of different control strategies as well as controller parameters on the system performance.

DC distribution grids are more and more considered an attractive solution to integrate renewable energy sources because of good matching with dc output voltage such as photovoltaic (PV) array systems, electric vehicles and distributed battery energy storage systems (BESS). To overcome the control problems involving coordination control schemes of multi-BESSs in real-time as well as optimized operation strategies of dc grids in long-term, this paper presents the adaptive coordinated droop control of multi-distributed battery energy storage systems in DC distribution grids. The adaptive coordinated droop is proposed to force real-time state of charge of BESS to track on the optimized scheduled state of charge (SOC) in long-term. Furthermore, in this approach, the energy storage units (ESUs) with higher SOC dispatch more power, while the ones with lower SOC dispatch less power. The SOC difference among ESUs exponentially reduces and finally the exchange power is equally shared between the distributed ESUs. Meanwhile, the exchange power share speed can be adjusted by changing the exponent of SOC in the adaptive coordinated droop control.