Abstract:To address the issues of electric submersible pumps (ESP) operating under complex working conditions and oilwell environments, including weak early abnormal features, significant inter-well data distribution drift, and the tendency of a single model to produce false positives and false negatives, we propose an ESP anomaly detection method based on large language models. By integrating data from multiple operating conditions and the corresponding oilwell background knowledge, we construct contextual inputs. We build a scalable ESP-domain instruction fine-tuning dataset, and based on multiple open-source small- and medium-parameter models, we build a collection of differentiated expert ESP anomaly diagnosis models via LoRA-based instruction fine-tuning, and employ a separate arbitration system to perform chain-of-thought reasoning and consistency verification over the set of expert outputs to generate the final decision. Experimental studies were conducted on ESP data from a drilling platform, validating the feasibility and stability of the proposed method; its accuracy is significantly superior to that of other mainstream machine learning or deep learning methods.