Wind Energy Harvesting System - Energy Harvesting Autonomous Sensor Systems - page 59

Main : 25 k 50 s/div

Voltage (V)

V cap

3

2

V in

1

I cap

0 50 100 150 200 250 300 350 400 Time (sec)

With WEH
without MPPT

With WEH
and MPPT

Without
WEH and
MPPT

FIGURE 2.21
Operation of the sensor node under various powering schemes.

Main : 25 k 50 s/div

Voltage (V)
2.9 V

V cap

3

2.75 V

2

1 I cap

0 50 100 150 200 250 300 350 400 Time (sec)

V in

With WEH, Without MPPT
Discharge Time = 350 sec

With WEH and MPPT
Charge Time = 150 sec

FIGURE 2.22
Performance of the WEH system with MPPT and without MPPT.