Abstract: For utilizing the domestic low grade waste heat resources, a Roots-type steam engine is developed. To make the roots engine stably output electric energy, an efficient constant power control system needs to be designed. The controlled object characteristics of the roots engine are analyzed; the modeling of the control system is established; and on this basis the fuzzy control algorithm is introduced. The fuzzy adaptive PID controller for the roots power machine constant power output is designed and the related MATLAB simulation is carried out. The results show that the Roots type steam power machine with fuzzy adaptive PID control algorithm can effectively eliminate the steam disturbance to achieve satisfactory control effect, which provide a strong theoretical guidance and basis for the engineering practice for the follow-up of roots engine constant power output control system.

Key words: roots-type power machine, fuzzy adaptive PID, control system simulation, low pressure steam generator