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The increasing use of power electronic based loads such as adjustable Speed drives, Switch mode power supplies, etc to improve system efficiency and Controllability is increasing concern for harmonic distortion levels in end use facilities and on overall power system. The application of passive tuned filters creates new system resonances, which are dependent on specific system conditions. In addition, passive filters often need to be significantly overrated to account for possible harmonic absorption from power system. Passive filter ratings must be coordinated with reactive power requirements of the loads and it is often difficult to design the filter to avoid leading power factor Operation for some load conditions. There are different ways to enhance power quality problems in transmission and distribution systems. Among these, the D-STATCOM is one of the most effective devices. A new PWM-based control scheme has been implemented to control the electronic valves in the DSTATCOM. The D-STATCOM has additional capability to sustain reactive current at low voltage, and can be developed as a voltage and frequency support by replacing capacitors with batteries as energy storage. STATCOM is often used in transmission system. When it is used in distribution system, it is called D-STATCOM in Distribution system). D-STATCOM is a key FACTS controller and it utilizes power electronics to solve many power quality problems commonly faced by distribution systems. Potential applications of D-STATCOM include power factor correction, voltage regulation, load balancing and harmonic reduction. Comparing with the SVC, the D-STATCOM has quicker response time an