Three Phase Auto Recloser Scheme
In this project an involuntary tripping system is to be built for 3-ÃƒÂ¸ supply system. The output of the project resets automatically after a transient interruption in the case of temporary fault occur otherwise it remains tripped in event of permanent fault. There may be any type of failures due to some faults which can be temporary or permanent in natue Ingrid substation or network through which the supply is delivered to the consumers i.e. domestic, industrial and commercial. These faults are the cause of significant detriment to the power system equipments. It is commonly observed In India that the failures in power system are due to the faults that occur during the transmission or distribution of electrical power. The faults can be LG (Line to Ground), LL (Line to Line), LLL (three phase) in the supply systems and these faults in3-ÃƒÂ¸supply system can affect the power system drastically. To deal with this problem an involuntry operating system is built, which can determine these faults and instinctively disconnects the supply to avoid severe damage to the switch gears and equipments in the electrical grid network. Six 1-ÃƒÂ¸ transformers are used in which 3 transformers are wired in star input and star output, and 3 transformers are wired in delta connections, having input 220V and output at 12V to develop the system. As it is hazardous to simulate faults on mains line so it is advised to follow the concept of low voltage testing of fault conditions? To determine the short duration and long duration fault conditions 555 timers are used. For the LL, LG and 3L fault creation in low voltage side, a number of fault simulator switches are used which activates the tripping mechanism. When the Short duration fault are subjected to system the tripping mechanism returns the supply to the load immediately and it is called as temporary trip while when the long duration faults occur in the system the tripping mechanism completely disconnects the faulty system from healthy system and it is called as permanent trip system.