Abstract: To address limited communication bandwidth and information eavesdropping risks in distribution network coordinated operation, this paper proposes a lightweight secure quantization-based transmission method with dynamic step sizes. Based on the cyber-physical coupled distribution network architecture, a multi-resource coordinated optimization model is established. A dynamic stochastic quantizer with error feedback is designed to reduce data volume via quantization and ensure transmission privacy through its inherent stochasticity. To mitigate steady-state oscillations induced by quantization deviation, a truncation error compensation mechanism is introduced, and a distributed coordinated algorithm directly processing quantized information is developed. Case studies conducted on a practical regional distribution network in Jiangsu Province demonstrate that the algorithm reduces bandwidth consumption and enhances privacy while guaranteeing convergence to optimal results, enabling reliable distributed coordination under bandwidth constraints, eavesdropping attacks, and intermittent communication packet loss scenarios.

Key words: distribution networks, data lightweighting, privacy protection, electric heating loads, consensus algorithm