Transmission-distribution long-term volt-var planning considering reactive power support capability of distributed PV

Nguyen, Quan H.; Ke, Xinda; Samaan, Nader A.; Holzer, Jesse T.; Elizondo, Marcelo A.; Zhou, Huifen; Hou, Zhangshuan; Huang, Renke; Vallem, Mallikarjuna R.; Vyakaranam, Bharat GNVSR; Ghosal, Malini; Makarov, Yuri V.

doi:10.1016/j.ijepes.2022.107955

DOE OSTI · 1995237

Transmission-distribution long-term volt-var planning considering reactive power support capability of distributed PV

Nguyen, Quan H.·Ke, Xinda·Samaan, Nader A.·Holzer, Jesse T.·Elizondo, Marcelo A.·Zhou, Huifen·Hou, Zhangshuan·Huang, Renke·Vallem, Mallikarjuna R.·Vyakaranam, Bharat GNVSR·Ghosal, Malini·Makarov, Yuri V.

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Abstract

High penetration of grid-edge, inverter-based photovoltaic (PV) can cause significant voltage fluctuations not only at the distribution but also at the sub-transmission levels due to PV output intermittency. Traditional reactive power planning approaches do not consider intermittency, nor the possibility of coordinating the control of existing and future volt-ampere reactive resources. This paper proposes a reactive power planning tool for sub-transmission systems to mitigate voltage violations and fluctuations caused by high PV penetration and intermittency with a minimum investment cost. The planning tool coordinates with an optimization-based volt-var operational tool for: a) modeling the coordination of all existing var assets in both sub-transmission and distribution systems to reduce the need of new equipment, and b)selecting a set of scenarios with voltage violations, derived from PV intermittency c) testing the final investment decision. The tool obtains an investment need for each intermittency scenario with a proposed optimal power-flow framework with efficient techniques to handle a high number of discrete variables. Two options are provided for final planning decision: i) a conservative direct combination of investment need solutions and ii) a machine learning-based selection of representative investment needs at most time steps. The final investment decision options are verified using a realistic large-scale sub-transmission system and 5-minute PV and load data. The results show a significant voltage performance improvement with a lower investment cost for additional var equipment compared to conventional approaches.

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14 SOLAR ENERGY optimal power flow photovoltaic principle component analysis reactive power planning volt-var control

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Nguyen, Quan H., Ke, Xinda, Samaan, Nader A., Holzer, Jesse T., Elizondo, Marcelo A., Zhou, Huifen, Hou, Zhangshuan, Huang, Renke, Vallem, Mallikarjuna R., Vyakaranam, Bharat GNVSR, Ghosal, Malini, Makarov, Yuri V.. 2022-01-13. Transmission-distribution long-term volt-var planning considering reactive power support capability of distributed PV. https://doi.org/10.1016/j.ijepes.2022.107955

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