Abstract The widespread integration of photovoltaics (PVs) presents significant challenges to the operation and control of distribution systems, particularly in maintaining voltage stability at nodes with PV connections. To address these challenges, this paper proposes a voltage control algorithm based on distributed model‐free adaptive control (MFAC). The control objective is to achieve real‐time reactive‐power‐voltage coordination under constraints including PV power output limitations, voltage safety ranges, and the communication network topology. The proposed method estimates dynamic linearization parameters that represent the voltage control characteristics of the distribution systems by utilizing real‐time data from distributed PVs and enabling communication between adjacent nodes. Rather than relying on a precise network model, the algorithm achieves robust voltage control by estimating these parameters from historical and real‐time sampling data, employing a data‐driven approach to iteratively update control strategies. Multi‐scenario simulations of a 32‐bus power system demonstrated the effectiveness and robustness of the algorithm across diverse operating conditions.