A hydrogen peroxide electric pump for throttleable hybrid rocket motor

The prosperity of commercial space drives the development of advanced rocket engines and propellants. Extensive research has shown that the electric pump feed system has good prospects in liquid rocket engine for its simplicity and controllability. However, the combination of electric pump feed system and hybrid motor has not been studied adequately. In this paper, design of a hydrogen peroxide electric pump for throttleable hybrid rocket motor is completed. In the scheme, a centrifugal pump is driven by a permanent magnet synchronous motor rated 75 kW and 36000 rpm with a sensor-less controller. The design of an axial backflow circulation is adopted in consideration of bearing lubrication and heat dissipation. The results of simulation and experiments show that the head and mass flow rate of the electric pump meets the requirement of target hybrid motor and the total efficiency reaches 58.6% under rated condition. The heat protection design is effective for the temperature rise during the operation is safe for hydrogen peroxide. Nonetheless, the acceleration of the motor still needs improvement. The results of this paper provide experimental verification of electric pump feed system for hybrid rocket motor.