ABSTRACT
This paper presents a study on the
modeling of a STAT-COM (Static Synchronous Compensator) used for reactive power
compensation on a distribution network. The power circuits of the D-STATCOM and
the distribution network are modeled by specific blocks from the Power System
Blockset while the control system is modeled by Simulink blocks. Static and
dynamic performance of a E3 Mvar D-STATCOM on a 25-kV network is evaluated. An
“average modeling” approach is proposed to simplify the PWM inverter operation
and to accelerate the simulation for control parameters adjusting purpose.
Simulation performance obtained with both modeling approaches are presented and
compared.
SOFTWARE: MATLAB/SIMULINK
CIRCUIT DIAGRAM:
Fig.
1. The cascade H-bridge converter based DSTATCOM.
EXPECTED SIMULATION RESULTS
Fig.
2 Waveforms
illustrating the D-STATCOM dynamic
performance.
Fig. 3 Voltage and current waveforms during the change
from inductive to capacitive operation at t = 0.2 s.
Fig. 4 Comparison between responses of detailed and
average models
for a step change in the network
internal voltage.
CONCLUSION
A detailed model of a D-STATCOM has been
developed for use in Simulink environment with the Power System Blockset. Models
of both power circuit and control system have been implemented in the same Simulink
diagram allowing smooth simulation. Two modeling approaches (device and average
modeling) have been presented and applied to the case of a +3Mvar D-STATCOM
connected to a 25-kV distribution network. The obtained simulation results have
demonstrated the validity of the developed models. Average modeling allows a faster
simulation which is well suited to controller tuning purposes.
REFERENCES
[1] K.K. Sen, “STATCOM: Theory,
Modeling, Applications,” in IEEE PES
1999 Winter Meeting Proceedings,
pp. 11 77- 1183.
[2] Flexible AC Transmission Systems (FACTS), edited by Y.H. Song and A.T. Johns, The
Institution of Electrical Engineers,
London, UK, 1999.
[3] K.V. Patil, et al., “Application of
STATCOM for Damping Torsional Oscillations in Series Compensated AC Systems,” IEEE Trans. on Energy Conversion, Vol.
13, No. 3,Sept. 1998, pp.237-243.
[4] C.D. Schauder, H. Mehta, “Vector
Analysis and Control of Advanced Static VAR Compensators,” IEE Proceedings- [SI Power System Blockset For Use with Sirnulink,
User’s Guide, The MathWorks Inc., 2000. C, Vol. 140, NO. 4, July 1993,
pp. 299-306.
