Reference Governors for Enforcing Compressor Surge Constraints

In turbocharged gasoline engines, the violation of the compressor surge constraint can be prevented by exploiting predictive control techniques based on the reference governor (RG). In this paper, two RG designs are considered: an inner-and an outer-loop RG. The inner-loop design governs the throttle command, and the outer-loop governs the requested air charge command. Numerical simulations and the experimental vehicle results are presented, showing that both designs enforce the surge constraint without the use of a compressor bypass valve, but that the inner-loop design requires scheduling in order to do so.