EXPERT SYSTEMS AND SOLUTIONS 48, North Street, Aranarai, Perambalur, Tamil Nadu, India.

Email ID: expertsyssol@yahoo.com, Website: www.researchprojects.info

Phone: 9952749533,

THYRISTOR SWITCHED REACTIVE POWER COMPENSATION

Block Diagram of Thyristor switched RPC System. In addition to not being able to achieve the desired power factor it is also possible

that the use of fixed compensation can also result in leading power factor under

certain load conditions. This is also unhealthy for the installation as it can result in

over voltage, saturation of transformers, etc. It is therefore necessary to automatically

vary without manual intervention, the compensation to suit the load requirements.

Some loads (such as welding equipments, injection moulding equipment, starting of

large induction motors, traction loads) which demand, under certain operating

conditions, large amount of reactive power for very short duration of time. Thyristor

switched automatic power factor correction system (Fig) is used in this application

which have a response time in milliseconds. In this system, it is possible to switch in

capacitors such that the inrush transient currents are totally eliminated. In addition

the capacitors can be switched repetitively intent any limits since, there is no need

for allowing discharge of the capacitor before it is switched in.