Application of Two Parallel-Connected DSTATCOMS for Distribution Substation Feeding Industrial Park
Power quality improvement is extremely important for an industrial park, not only from the point of view of consumers but also from the utility point of view. Therefore, it is advisable to mitigate the power quality issues, such as, voltage sag, voltage swell, poor power factor and source current harmonics in order to avoid overheating of equipment, vibrations and noise in motors, increased losses in different components and reduced efficiency of system. A novel method of connecting two DSTATCOMs at the receiving substation of industrial park is discussed in this paper. Simulation studies done using MATLAB/SIMULINK R2009a with voltage sag and swell and the different combinations of load have shown that, using two DSTATCOMs, simultaneous improvements can be achieved related to the various aspects of power quality, such as, voltage regulation, power factor improvement and harmonic reduction. Using one DSTATCOM, the utility can improve either the power factor or voltage regulation, but not both. Hence, application of two DSTATCOMs are discussed in this paper, so that one DSTATCOM takes care of power factor improvement and the other DSTATCOM maintains voltage regulation, and significant reduction in harmonics in line currents can also be obtained even with three-phase unbalanced load, non-linear load, open-conductor fault or line-to-line short-circuit fault at the load end. Keywords - DSTATCOM, power factor improvement, voltage regulation, harmonic reduction, power quality improvement.