Quantitative Assessment of Short-Term Photovoltaic Output Estimation Based on Sensor Measurements in an Actual Japanese Distribution Network

The importance of considering the photovoltaic (PV) output in distribution system operations and planning has increased. Voltage violations and equipment overloads may occur during PV output peaks, making accurate power flow analysis under such conditions essential. However, the PV output is typically measured as 30 min aggregated values by smart meters, which may underestimate the peak output and related power flow fluctuations. Installing high-resolution sensors at all the PV sites can address this issue; however, the associated costs are high. As a cost-effective alternative, high-resolution sensors can be deployed at representative PV sites, and their measurements can be used to estimate short-term outputs at surrounding PV sites. Implementing such an approach requires a quantitative evaluation of the relationship between the sensor number and PV output estimation accuracy. In the Chubu area of Japan, a trial region with sufficient high-resolution PV sensors exists, enabling detailed evaluation. This study developed a framework to estimate short-term PV outputs from representative sensors and used field data from the demonstration area to quantitatively assess the relationship between sensor deployment and estimation accuracy. These results provide guidance for designing cost-effective sensor placement strategies for practical network operations.