Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
auto selection of any available phase in 3 phase supply system pdf
#1

The project is designed to provide uninterrupted AC mains supply i.e., 230 volt to a single phase load. This is achieved by automatic changeover of the load from the missing phase to the next available phase in a 3 phase system.

It is often noticed that power interruption in distribution system is about 70% for single phase faults while other two phases are in normal condition. Thus, in any commercial or domestic power supply system where 3 phase is available, it is advisable to have an automatic changeover system for uninterrupted power to critical loads in the event of missing phase.

In this system auto selection is achieved by using a set of relays interconnected in such a way that if one of the relay feeding to the load remains energized always. Under the phase failure condition the corresponding step down transformer secondary delivers zero voltage which is duly rectified to DC and then fed to the logic gates comprising of AND & OR to switch on the next relay that delivers the power to the load.

It also has a provision of connecting to an inverter source which delivers uninterrupted power to the load incase all the 3 phases go missing. The project is supplied with three transformers connected to the 3 phases supply.

Further the project can be enhanced by incorporating power semiconductor devices such as thyristors/IGBTs for instantaneous changeover to the next available phase. This overcomes the drawback of the changeover time generally witnessed by relay switching operations.
Reply

#2
The main concept of this project is to maintain continuous AC supply to a single-phase load by an auto-changeover of load from the missing phase to any available phase in a three-phase system.

The proposed system uses a rectified-power supply. In this system, three phases areconnected to the control circuit through an Optoisolatorafterreducing the voltage level and rectifying it to DC using a step-down transformer and a half-wave rectifier, respectively. The load is selected from any of the availablethree phases, automatically, using relays,which are interfaced to the relay driver IC. The logic gates are used for detecting the availability of the phase.

The circuit is connected in such a way that the relays connected to the phase feeding the load are always energized. In case of the failure of this phase, the logic gates automatically generate an output to drive, so that the next relay is activated to connect the other available phases to feed the load.

This project in future can be enhanced by incorporating power semiconductor devices such as thyristors/IGBTs for instantaneous changeover to the next available phase. This overcomes the drawback of the change over time generally witnessed by the relay switching operations.
Reply

#3
Hi am Mohamed i would like to get details on auto selection of any available phase in 3 phase supply system pdf ..My friend Justin said auto selection of any available phase in 3 phase supply system pdf will be available here and now i am living at .. and i last studied in the college/school .. and now am doing ..i need help on ..etc
Reply

#4
I want to make this project as a final year project.
Reply



Forum Jump:


Users browsing this thread:
1 Guest(s)

Powered By MyBB, © 2002-2024 iAndrew & Melroy van den Berg.