The objective is to design output feedback event-triggered controllers to stabilize a class of nonlinear systems. One of the main difficulties of the problem is to ensure the existence of a minimum amount of time between two consecutive transmissions, which is essential in practice. We solve this issue by combining techniques from event-triggered and time-triggered control. The idea is to turn on the event-triggering mechanism only after a fixed amount of time has elapsed since the last transmission. This time is computed based on results on the stabilization of time-driven sampled-data systems. The overall strategy ensures an asymptotic stability property for the closed-loop system. The results are proved to be applicable to linear time-invariant (LTI) systems as a particular case.

We address the robust stabilization of nonlinear systems subject to exogenous inputs using event-triggered output feedback laws. The plant dynamics is affected by external disturbances, while the output measurement and the control input are corrupted by noises. The communication between the plant and the controller is ensured by a digital channel. The feedback law is constructed in continuous-time, meaning that we ignore the communication network at this step. We then design the sampling rule to preserve stability. Two implementation scenarios are investigated. We first consider the case where the sampling of the plant measurements and of the control input are generated by the same rule, which leads to synchronous transmissions. We then study the scenario where two different laws are used to sample the measurements on the one hand, and the control input on the other hand, thus leading to asynchronous transmissions. In both cases, the transmission conditions consist in waiting a fixed amount of time after each sampling instant and then in checking a state-dependent criterion: when the latter is violated, a transmission occurs. In that way, Zeno phenomenon is a fortiori excluded. The proposed hybrid controllers are shown to ensure either an input-to-state stability property or an Lp stability property, depending on the assumptions. The results are applied to linear time-invariant systems as a particular case, for which the assumptions are formulated as linear matrix inequalities. The proposed strategy encompasses time-driven (and so periodic) sampling as a particular case, for which the results are new. The effectiveness of the approach is illustrated on simulations for a physical system.

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In this study, the I-V and P-V curves of PV system at different solar radiations and ambient temperatures have been determined based on five-parameter equations describing the PV module. Also, the wind turbine performance model has been developed and the predicted power-speed curves have been validated against data sheet and experimental data. Both PV module and wind turbine models have been carried out in PSIM software environment. The sizing of hybrid PV/wind/storage battery power generation system has been implemented in HOMER software environment. The sizing results demonstrate that at meteorological conditions of solar radiation, wind speed, and ambient temperature in Borg Elarab area the PV/storage battery system is more feasible than hybrid PV/wind/storage battery system. Consequently, the PV/storage battery system has Net Present Cost (NPC) of $43571 against $45232 for hybrid PV/wind/storage battery system. In addition, by using fuel cell system with PV/storage battery system the excess electricity production is reduced from 1973 kWh/yr (22.4%) to 986 kWh/yr (8.7%) and NPC is reduced from $43571to $29744 which corresponds to about 31.73% reduction in system cost.

In this study, the I-V and P-V curves of PV system at different solar radiations and ambient temperatures have been determined based on five-parameter equations describing the PV module. Also, the wind turbine performance model has been developed and the predicted power-speed curves have been validated against data sheet and experimental data. Both PV module and wind turbine models have been carried out in PSIM software environment. The sizing of hybrid PV/wind/storage battery power generation system has been implemented in HOMER software environment. The sizing results demonstrate that at meteorological conditions of solar radiation, wind speed, and ambient temperature in Borg Elarab area the PV/storage battery system is more feasible than hybrid PV/wind/storage battery system. Consequently, the PV/storage battery system has Net Present Cost (NPC) of $43571 against $45232 for hybrid PV/wind/storage battery system. In addition, by using fuel cell system with PV/storage battery system the excess electricity production is reduced from 1973 kWh/yr (22.4%) to 986 kWh/yr (8.7%) and NPC is reduced from $43571to $29744 which corresponds to about 31.73% reduction in system cost.

In this study, the I-V and P-V curves of PV system at different solar radiations and ambient temperatures have been determined based on five-parameter equations describing the PV module. Also, the wind turbine performance model has been developed and the predicted power-speed curves have been validated against data sheet and experimental data. Both PV module and wind turbine models have been carried out in PSIM software environment. The sizing of hybrid PV/wind/storage battery power generation system has been implemented in HOMER software environment. The sizing results demonstrate that at meteorological conditions of solar radiation, wind speed, and ambient temperature in Borg Elarab area the PV/storage battery system is more feasible than hybrid PV/wind/storage battery system. Consequently, the PV/storage battery system has Net Present Cost (NPC) of $43571 against $45232 for hybrid PV/wind/storage battery system. In addition, by using fuel cell system with PV/storage battery system the excess electricity production is reduced from 1973 kWh/yr (22.4%) to 986 kWh/yr (8.7%) and NPC is reduced from $43571to $29744 which corresponds to about 31.73% reduction in system cost.