Benefits and design aspects of Sao Joao do Piaui 500 kV series capacitors

In summer of 2003 the Sao Joao do Piaui series compensation system located in the Brazilian Maranhao-Bahia 500 kV AC-network has been ordered and designed for delivery, erection and commissioning. The power demand of the growing Brazilian industries requires an economical solution for an increase of power transfer capability with the existing lines. Fixed series compensation has been found as the appropriate choice not only to enable the desired power increase but also to stabilize the interconnected networks by reducing the connecting line impedance. Starting of commercial operation of two capacitors located in two serial lines is scheduled for August 2004. This paper will give an overview of the design philosophy of the capacitor system and for the choice of the component rating.