This paper presents the model predictive control (MPC)
application
on the solar power system with microturbine and thermochemical energy
storage (TCES). To investigate the potential of a solar-powered turbine,
a solar receiver and a TCES are introduced to the Brayton cycle as
the replacement of the combustor. MPC is applied to offer the constrained
multi-variable real-time optimization control. To increase the practicability
in the solar industry, a custom-made multi-modeling approach is proposed
based on the close relationship between direct normal irradiance and
system states. Feedback correction mechanisms are designed to improve
the prediction and target tracking accuracies. During the regulatory
control under both extreme and realistic conditions, the multi-MPC
(MMPC) shows stronger adaptability and reliability than proportional–integration–differentiation
(PID) and higher tracking accuracies than the single-linear-model-based
MPC. Although the control performance could be further improved by
employing nonlinear MPC (NMPC), the much longer optimization time
of NMPC was unsuitable for real-time control. MMPC is further adapted
to track the grid demand, which is technically unachievable by PID
in the current system. While the output power precisely follows the
demand, the performance parameters can still stay close to their design
values, retaining a high system efficiency. Overall, the proposed
MMPC enables power demand tracking operation of solar air turbine
systems, and can ensure high stability and system efficiency.