When there is overload current and non-periodic current in the electrical circuit, it is easy to cause overheating of the line, and then cause electrical fire. However, the amount of existing electrical data is not enough to support the training of the electrical circuit over-temperature warning model, so it is necessary to simulate and model the causes of electrical circuit over-temperature. A simulation model for overload current and non-periodic current conditions in electrical circuits was proposed, which aims to simulate the current changes of electrical circuits under actual working conditions. The model is mainly composed of a constant power load module, a non-periodic current module, and a master control module. The results show that the model has a good simulation ability for the overload current of 1.1 ~ 1.4 times of the electrical circuit and the non-periodic current of 0 ~ 0.2 s and 0.1 ~ 0.4 s after the wavefront, and a large amount of data can be generated through the model simulation, which provides effective data support for the prediction and prevention of electrical fires.