Structural Design of the mCCHP-RES System - Design for Micro-Combined Cooling, Heating and Power Systems - page 139

food preparation. Moreover, complementary functions like lifts, garden, or
garage equipment may occur.
Estimation is done under two aspects: (a) the monthly consumption for

ful lling each function, (b) the form of energy consumed to support each

function. Further, by consumptions aggregating, the diagrams of the power
and heat consumption at system level are obtained.
The sixth step is Load estimation and consists in (a) construction of the load
diagrams at system level based on the consumption diagrams at the same level
(which have been obtained in the previous step), and (b) sharing this load on each
supplier, based on a load sharing strategy, which was previously established.
Finally, the load diagram of every system component is obtained.
The seventh step is Performance evaluation and consists in (a) evaluation
of the performance indicators for each potential structural model established in
the fourth step, and (b) elimination of the less ef cient models. Thus was made

up the set of structural models, which will be fully analyzed in the functional
design stage. One of these will be actually implemented.
(b) Functional design
This stage begins with the eighth step of the design process, namely System
functional modeling. Two actions take place within this step: (a) building the
potential functional models, and (b) sizing the system components.
The s structural

models into functional models, by completing them with the auxiliary com-
ponents (work

first action consists in the transformation of the system '

fluid recirculation pumps, ventilators, ventilator-convectors,
heat and power accumulators, heat exchangers, pipes, etc.).
The second action consists in determining the nominal values of the
components output which, on the one hand, should cover the components load
(estimated in the sixth step) and, on the other hand, should satisfy all the
balance equations regarding energy and mass ows.

The ninth step consists in elaborating the System operation and control
strategies. Starting point in this step is the observation that the momentary
values of the residence consumption modify permanently, depending on the
momentary necessities of the residence. In essence, these strategies regard the
manner in which the load of the system ed, so that

it might supply the residence with the necessary energy at all times.
The tenth step is System dynamics analysis and consists of the numerical
modeling of the mCCHP system and then of the simulation of the dynamic
operation for the electric and thermal subsystems in summer and winter
modes. The modeling and simulation are carried out for each functional
model, in view of comparatively analyzing the results obtained. These results
describe the behavior of the system in each particular case and allow a good
technical characterization.
The eleventh step is Design of the control subsystem and consists in car-
rying out two actions. The

' s components will be modi

first action is the design of the monitoring and
control system, which includes choosing the field equipment (transducers,