ABSTRACT
This
paper presents an implementation of sliding mode controller (SMC) along with a
proportional and integral (PI) controller for a DSTATCOM (Distribution STATic
COMpensator) for improving current induced power quality issues and voltage
regulation of three-phase self-excited induction generator (SEIG). The use of
SMC for regulating the DC link voltage of DSTATCOM offers various advantages
such as reduction in number of sensors for estimating reference currents and
the stable DC link voltage during transient conditions. The use of PI
controller for terminal voltage control gives the error free voltage regulation
in steady state conditions. The voltage regulation feature of DSTATCOM offers the
advantages of single point voltage operation at the generator terminals with
the reactive power compensation which avoids the saturation in the generator.
Other offered advantages are balanced generator currents under any loading
condition, harmonic currents mitigation, stable DC link voltage and the reduced
number of sensors. The SMC algorithm is successfully implemented on a DSTATCOM
employed with a three-phase SEIG feeding single phase or three phase loads. The
performance of the proposed control algorithm is found satisfactory for voltage
regulation and mitigation of power quality problems like reactive power
compensation, harmonics elimination, and load balancing under nonlinear/linear
loads.
SOFTWARE:
MATLAB/SIMULINK
SCHEMATIC DIAGRAM:
Fig.
1 Configuration of DSTATCOM supported induction generator
a
Schematic diagram of induction generator supported by VSC-based DSTATCOM
CONTROL DIAGRAM:
b
Control algorithm of DSTATCOM for estimation of reference currents using SMC
with
PI controller
EXPECTED SIMULATION RESULTS
Fig.
2 Simulation results of DSTATCOM
a
Performance of DSTATCOM under three-phase and single-phase non-linear load
b,
c Harmonic content of load current ila and generator current
CONCLUSION
A
DSTATCOM supported induction generator has been implemented with the SMC with
PI control algorithm for mitigating the power quality problems and it has
enhanced the active power capability of the generator. The SMC has been verified
for the dynamics in the DC-link voltage and found robust and acceptably fast to
avoid large variations in DC-link voltage. Moreover, from the experimental
results it has been inferred that the sliding mode control with PI controller
algorithm has been found capable of meeting various functionalities of DSTATCOM
such as voltage regulation, source currents balancing, harmonics mitigation,
and reactive power compensation.
REFERENCES
1
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2
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3
Rai, H., Tandan, A., Murthy, S.S., et al.: ‘Voltage regulation of self-excited induction
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4
Singh, B., Shilpakar, L.: ‘Analysis of a novel solid state voltage regulator
for a self-excited induction generator’, IEE Proc. Gener. Transm. Distrib.,
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5
Singh, B., Murthy, S.S., Gupta, S.: ‘A solid state controller for self-excited induction
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