2011 International Conference on Alternative Energy in Developing Countries and Emerging Economies
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From the above simulation (figure 5) results, we have some
very important observations, which are summarized in Table I
below:
TABLE I
O
BSERVATIONS
F
ROM
HOMER S
IMULATION
Considering Factors
Without
Flywheel
With
Flywheel
Electrical
Properties
Excess Electricity
3.27%
1.94%
Renewable Fraction
0.238
0.272
Maximum Renewable
Penetration
65.5%
76.6%
Diesel
Generator
(D925)
Electricity Generation
3540199
kWh/yr
3382941
kWh/yr
Fuel Consumption
965505
L/yr
933848 L/yr
Hydrogen
Generator
(Gen3)
Hours of Operations
752/yr
317/yr
Number of Starts
43848/yr
18727/yr
Hydrogen
Consumption
7223
kg/yr
3345 kg/yr
Mean Electrical
efficiency
34.6%
34.8%
Operational Life
53.2 yr
126 yr
Emission
Carbon Dioxide
2552953
kg/yr
2459094 kg/yr
Carbon Monoxide
6349
kg/yr
6092 kg/yr
Unburned
Hydrocarbon
703 kg/yr
675 kg/yr
The observations are carried out for two conditions. One is
simulation with flywheel and the other one is simulation
without a flywheel. Results clearly shows that an addition of a
flywheel system will reduce excess electricity, increase
maximum renewable penetration, reduce fuel consumption,
and number of diesel starts per year, increase operational life
and reduce emissions. Therefore, we suggest an addition of a
25kWh flywheel system to Ramea hybrid power system.
IV. E
XPERIMENTAL
S
ET
U
P AND
C
ONTROL
S
YSTEM
D
ESIGN
A dc machine based FESS consist of a dc motor/generator
unit coupled with a flywheel disk, a controllable power supply
unit with control input voltage(dc), a main control unit, a dc-
dc converter, an inverter and its protection circuit. There is
also a field control power supply present in the system to
control the field of the dc machine.
(a)
(b)
Fig. 6.2 Experimental Set-up of DC Flywheel Storage, (a) Flywheel coupled
with DC machine (b) Current sensor, voltage sensor, controller and relay
driving circuitry.
Fig. 6.1. DC Flywheel Energy Storage.
