Actuator Fault Tolerant System For Cryogenic Combustion Bench Cooling Circuit

Abstract

In this paper a method is proposed to design a fault tolerant control strategy based on a pressure and mass flow rate model, as well as a fault detection and isolation scheme to improve the reliability of a cryogenic bench operation. The fault is detected by the fault detection and isolation scheme composed of an extended unknown input observer, a cumulative sum algorithm and an exponentially moving average chart. Then the goal is to provide a fault tolerant system reconfiguration mechanism with a control law which compensates for the estimated actuator additive faults to maintain the overall system stability. For that purpose we use a linear quadratic regulator on an equivalent system where the unknown input is expressed as a function of the known state and known input vectors. The model and the estimation part were validated on the real Mascotte test bench (ONERA/CNES) data, and the reconfiguration control law was validated in realistic simulations.