Under the background of "carbon peak and carbon neutralization", the demand for automatic control system in new energy power stations will be higher and higher. Therefore, the overall construction scale of photovoltaic power stations will be further expanded. In order to ensure safe and stable operation, automatic generation control (AGC) and automatic voltage control (AVC) have been applied in photovoltaic power plants. This paper introduces an intelligent photovoltaic monitoring system, which uses hierarchical control technology to provide voltage control and active power control functions for photovoltaic power plants. The control system aims to make full use of the active and reactive power control capability of the PV generator set. Through the rapid coordination and control of photovoltaic generating units and additional devices, the accurate control of active and reactive power of photovoltaic stations and parallel nodes can be realized to meet the technical requirements of power grid upgrading.