Functional Design of the mCCHP-RES System - Design for Micro-Combined Cooling, Heating and Power Systems - page 299

var3
PV power
source

1000

Electrical power
of sources

Surplus/deficit

kW-W1

Vb

1
s
Integrator

2
Pe_St

1000 Vm+(VM-Vm)/(WM-Wm)*(u(1)-Wm) 3

Battery model

kW-W

3
Ce

var_st.mat
To File

Electrical
consumption

Accumulated
energy

1/0.7 4

Pe 5

Pe1

kW-W2

Fig. 42 “ Electrical battery ” simulation block

Electrical power profile graph

2
Out2
1
Out1

var2
24h power profile

1000

kW

Gain1

Fcn

1
In1

sgn(u) 0.202

Electrical power consumption
in domestic water circuit

Fig. 43 The detailed scheme of the “ electric consumption ” block

Choosing such a long interval was justi ed by the necessity to obtain the permanent

regime of the system, that is, to exhaust the transitory component, which is in

u-
enced by the initialization of the system (for example, the initial charging/dis-
charging regime of the battery).
Figures 42 and 43 present in detail the “ Electrical battery ” and the “ Electrical

consumption ” blocks. The operating conditions are given by the following imposed

requirements:

the thermal power consumed in the domestic water circuit is given by Fig. 44 ;

￿

the consumed electrical power is given by Fig. 45 . The evolution of this power
results based on a permanent load graph, given by Fig. 46 , to which the con-
sumption of the pumps from the domestic water circuit is added, when these
start to operate.

￿

Figure 47 gives the time evolution of the battery voltage and Fig. 48 shows the
energy accumulated in the battery. It can be noticed that, after the transitory regime,
these evolutions practically indicate a permanent one. That means the electrical