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Design of an Automatic Control Algorithm for Energy-Efficient ...

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8 System <strong>an</strong>d functionality integration 88<br />

0 if the constraint is satisfied <strong>an</strong>d values greater th<strong>an</strong> zero if not, as it is common <strong>for</strong><br />

optimisation problem <strong>for</strong>mulations [31].<br />

The constraints <strong>for</strong> the temperature <strong>an</strong>d the humidity <strong>of</strong> the inlet air are limited<br />

through the maximum heating/cooling power <strong>an</strong>d depend on the air flow. Equation 3.1.1<br />

<strong>an</strong>d equation 3.2.3 c<strong>an</strong> be used to implement a maximum <strong>an</strong>d minimum temperature<br />

constraint as well as a minimum humidity.<br />

The electric power limitation <strong>an</strong>d the upper air flow limit given by the cold air<br />

prevention have to be realised in this way, too. Other limitations <strong>for</strong> connected design<br />

variables, <strong>for</strong> example icing c<strong>an</strong> be integrated by a special objective.<br />

8.3 Parameters <strong>for</strong> the objectives<br />

In the following Table 8.2 <strong>an</strong> overview <strong>of</strong> the objectives so far presented <strong>an</strong>d their scaling<br />

method is given. The scaling c<strong>an</strong> be import<strong>an</strong>t <strong>for</strong> the compromise finding in combination<br />

with the weight. Moreover, possible priorities, weights <strong>an</strong>d limits are shown. Objectives<br />

regarding the application <strong>of</strong> a heat pump in a more general thermal m<strong>an</strong>agement are not<br />

listed since they depend a lot on the system.<br />

The objectives derived from the constraints are the simplest to parameterise. They<br />

have the highest priority, are not weighted <strong>an</strong>d have - with the st<strong>an</strong>dard <strong>for</strong>mulation as<br />

used be<strong>for</strong>e - the limit zero.<br />

For the objectives, a ���� <strong>of</strong> 255 is used. There<strong>for</strong>e, listed limits <strong>of</strong> 255 me<strong>an</strong> “no<br />

limit” since they c<strong>an</strong>not be exceeded. For the power consumption objectives it is not<br />

useful to set a limit since the calculation is based on the maximum powers. The air speed<br />

objective does not require <strong>an</strong>y limit since it is not very import<strong>an</strong>t. The humidity control<br />

will also not be limited as it is limited by physics (0-100% relative humidity). Another<br />

factor <strong>for</strong> this decision is that it is not completely controllable (cf. Section 8.2). For the<br />

fogging affinity a limit is given by the sensor accuracy to predict fogging. The air quality<br />

is required to stay below the OEL-value (cf. Section 2.2.4). In the case <strong>of</strong> the thermal<br />

com<strong>for</strong>t, a limit is used together with its p<strong>an</strong>ic h<strong>an</strong>dler (see Section 6.3.10) in order to<br />

guide a way out <strong>of</strong> a very uncom<strong>for</strong>table state.<br />

Priorities are chosen by import<strong>an</strong>ce. Safety related objectives, fogging <strong>an</strong>d air

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