Abstract:The design objective of the complex dual-tank system is to track the set-value of liquid level of the two sewer tanks. In order to achieve good performance of liquid level control, infinite horizon performance index of liquid level control is constructed, and mathematical description of infinite time performance optimization problem of complex dual-tank is established. Then, based on decomposition and coordination of time, the hierarchical optimization and rolling optimization idea of predictive control are introduced into the control problem of water tank. The large-scale parameter optimization problem caused by longer optimization horizon is decomposed into independent small-scale parameter optimization problem at each time point, and the explicit optimization solution is obtained, which achieves better performance of tank liquid level control.