Application of voltage sensitivity analysis in a probabilistic context for characterizing low voltage network operation

The proliferation of residential photovoltaic (PV) prosumers leads to detrimental impacts on the low-voltage (LV) distribution network operation such as reverse power flow, voltage fluctuations and voltage imbalances. This is due to the fact that the strategies for the PV inverters are usually designed to obtain the maximum energy from the panels. The most recent approach to these issues involves new inverter-based solutions. This paper proposes a novel comprehensive control strategy for the power electronic converters associated with PV installations to improve the operational performance of a four-wire LV distribution network. The objectives are to try to balance the currents demanded by consumers and to compensate the reactive power demanded by them at the expense of the remaining converters’ capacity. The strategy is implemented in each consumer installation, constituting a decentralized or distributed control and allowing its practical implementation based on local measurements. The algorithms were tested, in a yearly simulation horizon, on a typical Portuguese LV network to verify the impact of the high integration of the renewable energy sources in the network and the effectiveness and applicability of the proposed approach.

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A voltage sensitivity-based method for assessment of distributed energy resources impact in unbalanced low-voltage grids

2020 IEEE International Conference on Environment and Electrical Engineering and 2020 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe) ◽

10.1109/eeeic/icpseurope49358.2020.9160857 ◽

2020 ◽

Author(s):

Julian Sainz ◽

Andres Cortes ◽

Julia Merino ◽

Esther Torres

Keyword(s):

Low Voltage ◽

Energy Resources ◽

Distributed Energy Resources ◽

Voltage Sensitivity ◽

Distributed Energy

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Investigation of Var Compensation Schemes in Unbalanced Distribution Systems

Complexity ◽

10.1155/2019/7824743 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Yinuo Huang ◽

Licheng Wang ◽

Kai Wang

Keyword(s):

Distribution System ◽

Distribution Systems ◽

Low Voltage ◽

Current System ◽

Voltage Regulation ◽

Voltage Sensitivity ◽

Compensation Methods ◽

Distribution System Planning ◽

Var Compensation ◽

Phase Conductors

Distributed rooftop photovoltaic (PV) generators prospered distributed generation (DG) in recent years. Certain randomness of rooftop PV connection may lead to significant PV power imbalance across three phases, especially in low-voltage distribution systems. Due to interphase line coupling, traditional Var compensation methods which typically have competent voltage regulation performance may become less effective in such PV imbalance scenarios. In this paper, the limitation of traditional Var compensation methods in voltage regulation with unbalanced PV power integration is demonstrated and comprehensively analyzed. After describing the voltage regulation challenge, based on the voltage sensitivity analysis, it is revealed that PV power unbalanced level together with equivalent mutual impedance among phase conductors has a significant impact on the effectiveness of traditional Var compensation methods on voltage regulation. On this basis, to improve the performance of voltage regulation methods, some suggestions are proposed for both current system operation and future distribution system planning. Numerical studies demonstrate the effectiveness of the proposed suggestions. Future rooftop PV integration in LV systems can benefit from this research.

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