Variable dissolved oxygen set-points operation

© Springer International Publishing Switzerland 2017. In this chapter the higher level control of a two-level hierarchical structure is proposed using BSM1 as testing plant. The lower level is composed of the MPC+FF controllers described in the previous chapter.The higher level controller has to manipulate SO set-points of the lower level controllers according to SNH,5. The biological treatment of SNH and SNO is the result of various processes given by ASM1.When SNH increases, more SO is needed for nitrification. On the contrary, when SNH decreases, less SO is required, producing less SNO (Fig. 5.1). In this chapter, three alternatives are tested for the higher level: An MPC, an affine function and a FC. For each of these alternatives a range of tuning parameters is proposed. The control alternatives have been tested only by controlling the fifth reactor.