ABSTRACT:
In
the current scenario, integration of renewables, growth of non-linear
industrial and commercial loads results in various power quality issues. Among
commercial utilities connected to the grid, hospital-operated loads include
sensitive, linear, non-linear, and unbalanced loads. These loads are diverse as
well as prioritized, which also causes major power quality issues in the local
distribution system. Due to its widespread divergence, it leads to harmonic
injection and reactive power imbalance. Distribution Static Compensator
(DSTATCOM) is proposed as a solution for harmonic mitigation, load balancing,
reactive power imbalances, and neutral current compensation. The present work
utilizes Interval Type-2 Fuzzy Logic Controller (IT2FLC) with Recursive Least
Square (RLS) filter for generating switching pulses for IGBT switches in the
DSTATCOM to improve power quality in the Local Distribution Grid. The proposed
approach also shows superior performance over Type 1 fuzzy logic controller and
Conventional PI controller in mitigating harmonics. For effective realization,
the proposed system is simulated using MATLAB software.
KEYWORDS:
1. Local
distribution grid
2. DSTATCOM
3. Interval
type 2 fuzzy logic controller
4. Power
quality and recursive least square filter
SOFTWARE: MATLAB/SIMULINK
SCHEMATIC DIAGRAM:
Figure 1. Proposed Dstatcom Configuration With
Interval Type-2 Fuzzy Logic Controller.
EXPECTED SIMULATION RESULTS:
Figure 2. Source And Load Current
Waveforms Of The Hospital Loads Connected To Ldg Without Dstatcom.
Figure 3. Phase B Harmonic
Spectrum.
Figure 4. Source Current Waveforms
Of The Hospital Loads Connected To Ldg With Dstatcom.
Figure 5. Load Current Waveforms
Of The Hospital Loads Connected To Ldg With Dstatcom.
CONCLUSION:
The
performance of IT2FLC based DSTATCOM has been validated in this work and
satisfactory results corroborate its effectiveness when sensitive loads are
connected to the grid. With proficient behavior of control along with its fast response,
it has been proved effective in mitigating harmonics. The simulated results and
tabulation highlight the efficacy of the proposed controller over conventional
ones. This paper paid close attention to the effective operation of the local distribution
grid with sensitive loads which are the source of disturbances from the
generation viewpoint. Integration of IT2FLC based DSTATCOM in the system
significantly reduces the total harmonic distortion in the system and the RLS
filter helps in _ne-tuning it to the acute levels. Also, substantial improvement
in the total harmonic distortion is aided by reducing the harmonic value of
currents at the source side and provides a much better profile of voltage and
current waveforms. Neutral current flow due to unbalanced loads is mitigated
with the help of the fourth leg of VSC. Summarized results show that THD levels
are less when compared with PI controller and T1FLC at various time instant.
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