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Decentralized Energy-Management to Control Smart-Home <strong>Architecture</strong>s 159<br />

controll<strong>in</strong>g system, we are leav<strong>in</strong>g out the aspect <strong>of</strong> learn<strong>in</strong>g on the controller. In<br />

further work, we will <strong>in</strong>vestigate the controller’s aspect <strong>of</strong> learn<strong>in</strong>g, as proposed<br />

<strong>in</strong> Sect. 3. The observer/controller-architecture is an appropriate framework to<br />

implement learn<strong>in</strong>g techniques.<br />

Depend<strong>in</strong>g on the appliance’s degree <strong>of</strong> freedom and the planned schedule,<br />

an optimized schedule can be computed, which is based on the 24h-signal <strong>of</strong> the<br />

energy supplier. E. g., a dishwasher is <strong>of</strong>ten switched on after lunch at 12:10 p. m.<br />

on a certa<strong>in</strong> weekday. It will probably be switched on dur<strong>in</strong>g the same weekday’s<br />

timeslot <strong>in</strong> the next week. S<strong>in</strong>ce this timeslot is rated with a high demand by<br />

the 24h-signal, it is beneficial to re-schedule the start<strong>in</strong>g time <strong>of</strong> the dishwasher<br />

to a timeslot, where the demand for energy is as low as possible. The appliance’s<br />

degree <strong>of</strong> freedom has to be respected. The optimiz<strong>in</strong>g process has to determ<strong>in</strong>e<br />

the best start<strong>in</strong>g timeslot <strong>of</strong> each appliance. For that purpose, the function <strong>of</strong><br />

the demand-set and the 24h-signal’s rat<strong>in</strong>g are considered for each possible start<strong>in</strong>g<br />

timeslot. The appliance’s start is scheduled to the timeslot with the lowest<br />

<strong>in</strong>tegral value which is consistent with the operat<strong>in</strong>g constra<strong>in</strong>ts.<br />

5.4 Integration <strong>of</strong> an Electric Vehicle<br />

Additionally, the mobile storage <strong>in</strong> the electric vehicle is used to support the<br />

balanc<strong>in</strong>g process <strong>of</strong> demand and generation. Via the battery’s charge controller,<br />

the SHMD is able to manage the charge- and feed-back-process. Some appliances<br />

<strong>in</strong> the house with a poor degree <strong>of</strong> freedom cannot be re-scheduled <strong>in</strong>to a period<br />

<strong>of</strong> low demand. E. g., a stove is <strong>of</strong>ten switched on for cook<strong>in</strong>g before lunchtime,<br />

but this is a period with an extremely high demand. In this case, a vehicle’s<br />

battery can be used to feed-back electrical energy <strong>in</strong>to the grid. The SHMD<br />

can send a control signal to the controller <strong>of</strong> the electrical vehicle to request<br />

the feed-back <strong>of</strong> a certa<strong>in</strong> amount <strong>of</strong> electrical power. The start <strong>of</strong> the charg<strong>in</strong>g<br />

process <strong>of</strong> the car’s battery can also be scheduledbytheSHMD.Thecharg<strong>in</strong>g<br />

<strong>of</strong> a car battery causes a high electrical load. Thus, it is beneficial to re-schedule<br />

the charg<strong>in</strong>g process <strong>in</strong>to periods <strong>of</strong> low demand.<br />

6 Results<br />

In the upper diagram <strong>of</strong> Fig. 5, the forecast for the next 24 hours based on<br />

the history data’s analysis is visualized. Each <strong>of</strong> the <strong>in</strong>telligent appliances is<br />

scheduled <strong>in</strong> the time slot <strong>in</strong>terval, where it has been typically powered on dur<strong>in</strong>g<br />

the considered period. The lower diagram represents the optimized schedule by<br />

the SHMD. The gray curve shows the behavior request from the grid operator<br />

(motivated <strong>in</strong> Sect. 5). It is shown that, e. g., devices like the breadmaker, the<br />

dishwasher, and the stove are located <strong>in</strong> periods <strong>of</strong> high demand, hence they<br />

should be re-scheduled.<br />

The breadmaker and the dishwasher have a sufficient degree <strong>of</strong> freedom. Thus,<br />

they can be re-scheduled to periods <strong>of</strong> lower demand, as shown <strong>in</strong> the lower<br />

diagram <strong>of</strong> Fig. 5. The stove has a poor degree <strong>of</strong> freedom. Therefore, it cannot

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