ABSTRACT:
KEYWORDS:
1. Bidirectional power flow
2. Distributed generator
3. Droop controller
4. Ac/dc hybrid microgrid
SOFTWARE: MATLAB/SIMULINK
CONTROL DIAGRAM:
Figure 1. General Converter-Based Dg Control Structure.
EXPECTED SIMULATION
RESULTS:
Figure 2. Dynamic Responses For Dc To Ac Power Flow Condition
Without Ic Reactive Power Support.
Figure 3. Dynamic Responses For Dc To Ac Power Flow Condition
With Ic Reactive Power Support.
Figure 4. Dynamic Responses For Ac To Dc Power Flow Condition.
Figure 5. Dynamic Responses For An Increase In The Ac Power Generation
Capacity.
Figure 6. Dynamic Responses For An Increase In The Dc Power Generation
Capacity.
Figure 7. Dynamic Responses For Ac To Dc Power Flow Condition
In Case
Of (Pac V ) And (Qac !) Droop Control In The Ac Subgrid. Figure 16. Dynamic Responses For Ac
To Dc Power Flow Condition In Case Of (Pac V ) And (Qac !) Droop Control In The Ac Subgrid.
CONCLUSION:
The
operating point including the amount and direction of the power flow between ac
and dc subgrids in an HMG largely affects the stability. Thus, this paper
investigated the impact of the power flow on the stability of HMGs formed by
the interconnection of ac and dc subgrids through bidirectional ICs. It is
observed that as the power flow from the ac to dc subgrid increases, the
stability margin of the HMG may be reduced. This is mainly because when the
power is exchanged from the ac to dc subgrid, the dynamics associated with the ac
subgrid have greater influence on the HMG stability as compared to those of the
dc subgrid. Moreover, an increase in the generation capacity of the ac subgrid
increases the power flow from the ac to dc subgrid to supply the dc load power,
which could degrade the stability of the HMG. Thus, it is technically advised
to design the HMG such that the ac subgrid receives power from the dc subgrid.
The stability analysis presented in this paper is not meant to emphasize that
the amount and direction of the power transfer could always jeopardize the
stability but rather, precaution should be exercised when transferring power from
one subgrid to the other.
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