Rural electrification remains a great challenge for Sub-Saharan Africa (SSA) as access to electricity is a prerequisite to accelerate its development. The present paper reviews the measures adopted to promote access t...Rural electrification remains a great challenge for Sub-Saharan Africa (SSA) as access to electricity is a prerequisite to accelerate its development. The present paper reviews the measures adopted to promote access to electricity in rural and remote areas of SSA. The main barriers to rural electrification in these developing countries are presented before showing technologies used for the aforementioned purpose. Then, adopted methods for enhancing the use of renewable energy in SSA are shown. Moreover, the policy adopted by decision makers and project planners are also highlighted. In addition, the optimal solutions proposed by researchers are given such as the cost-effective off-grid system type that might be a viable alternative to diesel power generation.展开更多
Domestic off-grid renewable energy systems have become common place in many areas of the world, as humanity seeks to keep abreast with global technological changes and advancements. This paper aims to present a cost-e...Domestic off-grid renewable energy systems have become common place in many areas of the world, as humanity seeks to keep abreast with global technological changes and advancements. This paper aims to present a cost-effective energy monitoring system which may be used to analyze and evaluate the operation of a domestic off-grid PV system. Parameters which are monitored include the output voltage and current from a 55 W polycrystalline PV panel. The output voltage and current from a power regulation circuit (which could be a DC-DC converter, solar charger or MPPT) is also monitored with this singular system which incorporates a data logging interface circuit, a data logger and a personal computer.展开更多
In order to more easily highlight the influence of cooled ambient air through an air-ground heat exchanger on the process of diffusion and mixing of heat around an electronic component and a photovoltaic solar module,...In order to more easily highlight the influence of cooled ambient air through an air-ground heat exchanger on the process of diffusion and mixing of heat around an electronic component and a photovoltaic solar module, we undertook to study the thermal field beforehand. The turbulent model has applied a realizable k-ε two equations model and the two-dimensional Reynolds Averaged Navier-Stokes (RANS) equations are discretized with the second order upwind scheme. The SIMPLE algorithm, which is developed using control volumes, is adopted as the numerical procedure. Calculations were performed for a wide variation of the Reynolds numbers. Our results reveal, on the one hand, that the use of an air-ground heat exchanger accelerates the dispersion of the thermal field around the PV panel. On the other hand, with increasing Reynolds number, the instabilities appear in the wake zone, showing an oscillatory flow, also called von Karman Vortex Street. Our air-ground heat exchanger has an important influence on the diffusion process of the thermal field. Comparison of numerical results with the experimental data available in the literature is satisfactory.展开更多
为应对大规模分布式光伏(photovoltaic,PV)接入引起的主动配电网电压越限问题,降低控制策略的时序复杂性,提出一种考虑节点功率储备与节点影响力(global importance of each node,GIN)的主动配电网动态集群电压控制方法。首先,通过考虑...为应对大规模分布式光伏(photovoltaic,PV)接入引起的主动配电网电压越限问题,降低控制策略的时序复杂性,提出一种考虑节点功率储备与节点影响力(global importance of each node,GIN)的主动配电网动态集群电压控制方法。首先,通过考虑系统各节点的功率储备度,定义聚类算法的电压灵敏度-功率储备度(voltage sensitivity-power reserve,VS-PR)综合电气距离量度。进而,以GIN算法改进亲和力传播(affinity propagation,AP)聚类算法,实现网络集群划分与主导节点选取。然后,建立主动配电网集群电压控制模型,并通过动态粒子群算法(dynamic particle swarm optimization,D-PSO)进行模型求解。最后,通过建立基于MATLAB 2021b平台的IEEE 33节点仿真算例对比分析,验证了所提动态集群划分与电压控制方法的正确性和有效性。展开更多
文摘Rural electrification remains a great challenge for Sub-Saharan Africa (SSA) as access to electricity is a prerequisite to accelerate its development. The present paper reviews the measures adopted to promote access to electricity in rural and remote areas of SSA. The main barriers to rural electrification in these developing countries are presented before showing technologies used for the aforementioned purpose. Then, adopted methods for enhancing the use of renewable energy in SSA are shown. Moreover, the policy adopted by decision makers and project planners are also highlighted. In addition, the optimal solutions proposed by researchers are given such as the cost-effective off-grid system type that might be a viable alternative to diesel power generation.
文摘Domestic off-grid renewable energy systems have become common place in many areas of the world, as humanity seeks to keep abreast with global technological changes and advancements. This paper aims to present a cost-effective energy monitoring system which may be used to analyze and evaluate the operation of a domestic off-grid PV system. Parameters which are monitored include the output voltage and current from a 55 W polycrystalline PV panel. The output voltage and current from a power regulation circuit (which could be a DC-DC converter, solar charger or MPPT) is also monitored with this singular system which incorporates a data logging interface circuit, a data logger and a personal computer.
文摘In order to more easily highlight the influence of cooled ambient air through an air-ground heat exchanger on the process of diffusion and mixing of heat around an electronic component and a photovoltaic solar module, we undertook to study the thermal field beforehand. The turbulent model has applied a realizable k-ε two equations model and the two-dimensional Reynolds Averaged Navier-Stokes (RANS) equations are discretized with the second order upwind scheme. The SIMPLE algorithm, which is developed using control volumes, is adopted as the numerical procedure. Calculations were performed for a wide variation of the Reynolds numbers. Our results reveal, on the one hand, that the use of an air-ground heat exchanger accelerates the dispersion of the thermal field around the PV panel. On the other hand, with increasing Reynolds number, the instabilities appear in the wake zone, showing an oscillatory flow, also called von Karman Vortex Street. Our air-ground heat exchanger has an important influence on the diffusion process of the thermal field. Comparison of numerical results with the experimental data available in the literature is satisfactory.