ABSTRACT:
Recently,
a lot of distributed generations such as wind power generation are going to be installed
into power systems. However, the fluctuation of these generator outputs affects
the system frequency. Therefore, introduction of battery system to the power
system has been considered in order to suppress the fluctuation of the total
power output of the distributed generation. For frequency analysis, we use the interconnected
2-area power system model. It is assumed that a small control area with a large
penetration of wind power plants is interconnected into a large control area.
In this system, the tie line power fluctuation is very large as well as the
system frequency fluctuation. It is shown that the installed battery can suppress
these fluctuations and that the effect of battery on suppression of
fluctuations depends on the battery capacity. Then, the required battery capacity
for suppressing the tie line power deviation within a given level is calculated.
KEYWORDS:
1. Battery
2. Distributed Generation
3. Frequency
4. Load
Frequency Control (LFC)
5. Power
System
6. Tie
Line Power
7.
Wind Power Generation
SOFTWARE:
MATLAB/SIMULINK
2-AREA POWER SYSTEM:
Fig. 1. 2-area power system model for frequency
control.
EXPECTED SIMULATION RESULTS:
Fig.2.
Impact of LFC control method.
Fig.
3. Behaviors of tie line power flow, system frequency and battery
output
with/without battery (Kb = 0.5, Tb = 0.5).
Fig.
4 Behaviors of tie line power and output and stored energy of battery
(9OMWh,
1500MW)
CONCLUSION:
In
this paper, we have analyzed the impact of installed wind power generation and
battery on the system frequency and the tie line power. In 2-area power
systems, the tie line power fluctuation is remarkably large as well as the system
frequency fluctuation. It has been made clear that the installed battery can
suppress these fluctuations and that the effect of battery on suppression of
these fluctuations depends on battery capacity. If the stored energy of battery
reaches the full capacity, the battery output changes to zero suddenly and the large
fluctuation is caused. Therefore, the stored energy needs
to be controlled within the rated storage capacity Based on this need, the required
battery capacity for suppressing the tie line power deviation within a reference
level has been calculated. If battery and LFC generator are controlled cooperatively,
installation of battery with a larger capacity makes it possible to decrease LFC
capacity of the conventional generators.
In the near future, a new method to calculate the optimal battery storage capacity (MWh) and the appropriate
power converter capacity (MW) for various kinds of wind power generation
patterns and an effective control method of the battery system for reducing the
battery capacity and LFC capability of the conventional power plants will be
studied.
REFERENCES:
[1]
W. El-Khattam and M. M. A. Salama, "Distributed generation technologies,
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[2]
N. Jaleeli, L. S. VanSlyck, D. N. Ewart, L. H. Fink, and A. G. Hoffmann,
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[3]
A. Murakami, A. Yokoyama, and Y. Tada, "Basic study on battery capacity evaluation
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Japanese)
[4]
P. Kunder, "Power System Stability and Control, " McGraw-Hill, 1994.
[5]
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