Based on scraper conveyor soft start requirements, CST controllable starting device was taken as the research object, through AMESim software was used to create the scraper conveyer motor and control system of CST whole model, according to the actual situation of the simulation analysis and calculation, he simulation control system was finished by parameter analysis on the basis of CST, the no-load condition and the chain scraper conveyer in the cases of controllable start-up were studied, the results showed that the model could accurately reflect the actual operating characteristics, PID control system can achieve fast response card chain protection, verify the feasibility of model.