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A high penetration of solar photovoltaic (PV) resources into distribution networks may create voltage rise problem when the generation from PV resources substantially exceeds the load demand. To reduce the voltage rise, the excess amount of power from the solar PV units needs to be reduced. In this paper, distributed storage systems are proposed for the mitigation of voltage rise problem. The surplus energy from the solar PV is used to charge the distributed storage units during midday, when the power from the solar PV would be typically higher than the load level. This stored energy is then used to reduce the peak load in the evening. An intelligent strategy for charging and discharging control to make effective use of the storage capacity is discussed. The proposed voltage rise mitigation strategy is verified on a practical low voltage distribution feeder in Australia. [ABSTRACT FROM PUBLISHER]

Distributed Generation is growing at important rates due to several reasons, including, in some countries, the strong penetration of renewable generating plants. Voltage rise is a considerable problem that prevents generators from injecting more active power into distribution networks. After a review of recently proposed mitigation techniques, a voltage rise mitigation technique is presented. The technique is based on a coordinated reactive power control of the distributed generators which takes into account the capability limits of the generators. It is suitable for utilization in distribution networks equipped with or without a dedicated communication infrastructure. [ABSTRACT FROM PUBLISHER]

Increasing load and the growing proportion of injected power from distributed energy generation lead to higher loading of distribution grids. Without suitable improvements like e. g. additional cables or substations, violations of voltage constraints in low voltage distribution grids have to be expected. A further alternative is represented by on-load tap-changers (OLTC) which are combined with distribution transformers. This paper presents an enhanced method for controlling them using a voltage range as input parameter. The voltage drop or rise between the substation and the first nodes of the strings is taken into account as it can be determined with little effort. This enables the consideration of similar loading in the strings of a distribution grid. The results of the simulations prove the advantages compared to the underlying approach. The improved method features less switching operations which leads to less wear and accordingly to lower maintenance effort. [ABSTRACT FROM PUBLISHER]

South Africa, with steep population and economic growth is suffering from energy deficit, like many other developing countries. The demand is becoming greater than the available generation in the country. Hence, much research is on in South Africa regarding deployment of alternative energy sources such as solar PV and wind plants for local energy generation to supply remote and off-grid areas. Currently, solar photovoltaic (PV) is expensive especially when it is off-grid. Lately much research has been going into the integration of on-grid home-based solar PV (HBSPV) systems to the grid such that customers can get both solar and utility grid power according to periods of sun and no-sun. Also, with proper legislation, the customers might also be able to sell excess solar power to the utility grid. However, it is important to investigate the impact of integrating HBSPV systems on the voltage quality in the grid. This paper investigates the problem of voltage rise in the grid which might be caused by high level of penetration of on-grid HBSPV systems. In this study, the HBSPV system is modeled as a static generator and different bus voltages were recorded and studied for different levels of HBSPV penetration on a 9-bus test system. [ABSTRACT FROM PUBLISHER]