It has been required to install a large number of renewable energy (RE), such as photovoltaic systems (PVs) to solve the environmental problem. However, an electricity grid with RE occurs problems of power shortages and surpluses because of uncertainties in generating RE outputs. In addition, demand response (DR) can restrain both shortages and surpluses caused by PV outputs, but, on the other hand, DR may increase the impact of power shortages and surpluses due to the uncertainties of DR capabilities. Energy storage systems (ESSs) can be used to solve supply reliability problems, but the number of installed ESSs should be minimized considering their high cost. This study demonstrates that the optimal allocation of PVs and ESSs can be achieved that satisfies minimization of installed ESSs, the PVs installation target, and the constraints of the probabilistic indices for shortage and surplus to evaluate uncertainties of PV outputs and DR capabilities. The results show that PVs and ESSs are allocated in each bus, satisfying the PV installation target and the constraints of the supply reliability.

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Spacecraft drag-free control is an effective way to make satellite orbit only shaped by gravity and to achieve accurate and quiet alignment of the spacecraft axes to their reference. Essential measurements come from fine accelerometers. Exploiting the experience of the GOCE satellite drag-free and attitude control, the paper provides an integrated modelling and control design procedure which encompasses accelerometer and spacecraft control. Essential to this framework is the stochastic modelling and prediction of the unknown disturbance class to be counteracted. Stochastic modelling of disturbance is the key asset of the Embedded Model Control methodology. Among other advantages it allows robust decoupling of state prediction and control for complex dynamic systems.

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In this research, liquid level control of separator in an ocean thermal energy conversion (OTEC) experimental plant with Uehara cycle is considered. A linear control system representation is obtained from a liquid level model of separator in the OTEC experimental plant via weighted least squares by taking into account noises. The control mechanism for liquid level control is constructed based on LQG control theory. In order to verify the behavior of the constructed control system, a simulation was conducted.

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