Functional Design of the mCCHP-RES System - Design for Micro-Combined Cooling, Heating and Power Systems - page 309

Battery voltage

49

V ref

48.5

48

47.5

47

0 0.5 1 1.5 2 2.5

x 10 5

Time [s]

Fig. 64 Battery voltage evolution in winter regime, model 2

Electrical power

3.5

3

2.5

2

1.5

1

0.5

0

0 1 2

0.5 1.5 2.5

x 10 5

Time [s]

Fig. 65 Evolution of the electrical power produced by Stirling engine in winter regime, model 2

The evolutions of the battery voltage and of the electrical power delivered by the
Stirling engine are presented in Figs. 64 and 65 , respectively. The control loop
within the electrical subsystem manages to maintain the voltage average value at a
setpoint equal to 48.5 V. In the same time, the control loop within the thermal
subsystem maintains the temperature of the thermal agent in the accumulation tank
at a setpoint equal to 72 C (Fig. 66 ). The electrical power of the Stirling engine is

greater than the one mentioned in the case of model 1 (see Fig. 52 ), due to the fact
that the PV source is missing. Consequently, the average value of the pellet boiler
power (Fig. 67 ) is smaller than in the case of model 1 (see Fig. 51 ).

°

4.5.2 Modeling and Numerical Simulation of the System
in Summer Regime

The numerical simulation scheme is given by Fig. 53 , in which the PV source was
removed from the block. The evolutions of the controlled

values and of the powers controlled by the two controllers are presented in Figs. 68 ,
69 , 70 , and 71 . One can notice that a permanent regime is obtained in the battery

“ Electrical battery ”