Page 23 - Renewable Energy Devices and System with Simulations in MATLAB and ANSYS

10 Renewable Energy Devices and Systems with Simulations in MATLAB and ANSYS ®
®

Fuel cell stack Power electronics system Power grid
+ Converter υ Inverter Transformer
Air/oxygen υ FC DC
OO υ g
HH
Hydrogen H H H H
storage H H HH – DC DC DC AC
O
HH υ
Water FC υ DC υ g
FIGURE 1.13 Fuel cell system with DC/DC and DC/AC power electronics converters for AC power grid
connection.

FIGURE 1.14 Low-temperature PEM fuel cell setup at Aalborg University with approximate 1.2 kW electri-
cal capacity (28 cells each of 43 W) and hydrogen as fuel.

Wave energy Power electronics system Power grid
Generator υ ge Rectifier υ DC Inverter Transformer
Gearbox υ
Wave G g

AC DC DC AC
υ ge υ DC υ g

FIGURE 1.15 Wave energy system including an electric generator and AC/DC and DC/AC power electron-
ics converters for AC power grid connection.

power output, increasing lifetime, simplification, and cost reduction. A major potential advantage is
considered to be the fact that energy can be stored in the form of hydrogen that could be produced
using different forms of renewable energy but which in turn would require a different infrastructure
than the legacy power systems.
More than 70% of the earth surface is covered by water, making oceans and seas a potentially huge
energy resource, which is yet largely untapped. In the example solution, as depicted in Figure 1.15,
the movement of waves engages a mechanical transmission that is coupled to an electric generator.
The very low speeds and large power variations require special solutions and may result in relatively
reduced conversion efficiencies. Long-term reliability under very harsh environmental conditions