Over the past few years, distributed generation with solar sources has been integrated into the distribution network. The power system control equipment installed prior to the large accommodation of photovoltaic (PV) generators is not designed to protect the system against overvoltages occurring at point of common coupling. Therefore, it is essential to appropriately set the control modes through regulation curve adjustments included in smart inverters to help mitigate voltage stability issues in the network from the perspectives of generation and distribution, that are areas where PV systems are most commonly installed. Besides, it is crucial to assess the effectiveness of the selected Volt-Watt and Volt-var curves through the simulation of the IEEE 34 bus medium voltage distribution system, with the incorporating PV generators using the software OpenDSS and Python. The results of the simulation demonstrated that the Volt-var curves had better performance in the implemented system as they prevented voltage violations, and the output power of the affected photovoltaic systems remained close to the maximum capacity. Key words: Distributed generation, overvoltage, Volt-var curve, Volt-Watt cu