Analysis of the Impact of Distributed Power Sources on Distribution Network Voltage Stability Based on Newton Raphson Method

The connection of a high percentage of distributed PV to the distribution grid may lead to increased voltage fluctuations and instability at various nodes in the grid. The stochastic and intermittent power generation characteristics of the PV system may lead to power fluctuations in the grid, which in turn may affect the voltage level at each node. Especially during the peak hours of PV power generation, the voltage may increase, leading to unstable power system operation and even affecting the normal operation of user equipment. Therefore, it must be analyzed in order to better facilitate human life. Traditional power flow calculation methods, such as Gaussian Seidel method, tend to have difficult convergence features for sick condition systems. Therefore, it is not suitable for large-scale use. In this paper, based on Newton Raphson's method, we write a program to calculate the tidal current through Matlab, simulate the model of distributed power supply access to the distribution network and carry out the tidal current calculation, and finally analyze the steady state impact of distributed power supply access to the distribution network. The simulation results show that in the case of a large number of distributed photovoltaic connections, the Newton-Raphson method is used to calculate the power flow, which is fast and accurate. In practice, it can well avoid the phenomenon that the fault occurs and cannot be dealt with in time, and provides more accurate data for the relay protection system. In addition, it also provides a reliable reference for the access location of distributed photovoltaics, and can quickly obtain the degree to which the voltage of each location is affected by distributed photovoltaics after different locations are connected to distributed photovoltaics.