Research on security evaluation and improvement measures of distribution network under the background of high charging penetration rate

Abstract Under the conditions of scarcity of fossil energy and increasing environmental pollution, solar energy as an important renewable energy source has been emphasized by countries all over the world due to its cleanliness, large reserves, and sustainable use. With the increasing penetration rate of distributed photovoltaic, the distribution network has started to show new features such as diversified operation modes, bidirectional currents, and complex stabilization mechanisms, which brings new challenges to the safe and stable operation of the distribution network in the new situation. Therefore, this paper investigates the security evaluation and improvement measures of the distribution network under the background of high charging penetration rate. First, considering the uncertainty of photovoltaic (PV) output and load demand, a distribution network operation risk assessment method based on the improved put forward Monte Carlo sampling is proposed, and the low deviation sequence is improved by combining randomization and linear scrambling, while the improvement measures are studied based on the real-time tariff model and the demand response mechanism of the residential load model. Finally, the simulation analysis is carried out using the IEEE-34 node system. The results show that with the increasing penetration rate of distributed PV, the risk of node voltage overrun and the risk of partial branch current overrun also increase, and compared with the traditional method, the risk value obtained by the method proposed in this paper can reflect the real situation more accurately and stably.