An adaptive control for supporting village power grid integrating residential PV power generation

Abstract

Building a robust and capable village power networks plays an important role for responding to national strategic goals of “village revitalization”, “peak carbon dioxide emission” and “carbon neutrality”. At present, user-side distributed photovoltaic (PV) power is encouraged to be implemented in rural areas in China which brings about tremendous pressure to village power grids. Those power grids are already under vulnerable and inferior conditions in reality. Since PV power systems featuring volatility and randomness are commonly implemented in different lines across low-voltage distribution networks (LVDN) in village power networks in Chinese rural area, power imbalance affects the reliability of power supply. There is an urgent need for developing adaptive control strategies for managing this kind of distributed PV systems. This paper firstly studies the topology of a three-phase-four-line LVDN with regulated parameters. Afterwards, by analyzing the operational costs of the power grid and equipment reliability, a two-stage control scheme is proposed. Furthermore, the imbalance of three phase power systems, network losses, transformer losses are considered to form a multi-objective optimization problem which is solved by tuning transformer voltage, reactive power from PV inverters, energy storage system and demand response schemes. An actual LVDN and associated parameters from a real power distribution networks in Bijie region in Guizhou province, China are used in this study. The effectiveness of the proposed method is tested where 32.1% of power loss is reduced with three-phase imbalance being obviously mitigated accordingly.

Keywords

• Adaptive control
• Distributed photovoltaic power system
• Low-voltage distribution network
• Power substitution
• Two-stage control scheme