Why Use Series Capacitor Compensation in Distribution Systems?
Shunt compensation essentially reduces the current flow everywhere upto the point where capacitors are located and all other advantages follow from this fact.But series compensation acts directly on the series reactance of the line. It reduces the transfer reactance between supply point and the load and thereby reduces the voltage drop. Series capacitor can be thought of as a voltage regulator, which adds a voltage proportional to the load current and there by improves the load voltage. Series compensation is employed in EHV lines to 1) improve the power transfer capability 2) improve voltage regulation 3) improve the load sharing between parallel lines. Economic factors along with the possible occurrence of sub-synchronous resonance in the system will decide the extent of compensation employed. Series capacitors, with their inherent ability to add a voltage proportional to load current, will be the ideal solution for handling the voltage dip problem brought about by motor starting, ar
