Development of an Arduino based program to handle automatic phase selection for reliable power distribution

Abstract

The aim of this research was to develop and implement an automatic phase selector that will be used to provide a reliable power supply to the load in distribution system. It explains why the selection of a good power quality phase (live wire) among the 3 phases in distribution system using Arduino is preferable than employing a manual phase selection in case of a power failure especially when one phase (live wire) is missing. This thesis had revised the previous studies done on phase selection system and suggested the areas of improvement. Both voltage transformers, relays, diodes, Arduino and GSM have been used for the implementation of this project. This device will be used for single phase load; the 3 phases will be fed to this device and Arduino will compare the voltage of every phase so that the good phase will be supplied to the load when one phase is missing the supply authority will be informed via SMS. As an expected result when one phase failed another good power quality phase will be automatically selected and fed the load without any notice of phase failure to the load. To solve the effect of phase failure problem in power systems, this research suggested a powerful Arduino based program using c programming to handle the problem. For the selection of phases, the implemented circuit first check voltage range of each phase that is 207V minimum if the voltage is within the range the corresponding LED is ON showing that this phase is ready to supply the Load unless the LED is OFF. The highest phase voltage is only allowed to supply the load when the allowed phase is overloaded, the circuit compare the inputs voltage and select another phase that supply the load. If also the selected phase is missing the circuit again select another good phase to supply the load. Experiment shows that the indicator(LEDs) are on only if the corresponding phase voltage is within the accepted voltage rage for example if voltage on phase R is 216.21V, voltage on phase Y is 209.84V and Phase on voltage 201.05V; only Red and Yellow LEDs are ON while blue LED is Off. Also experiment shows that the allowed voltage range phase supplies the load for example if Voltage on phase R is 196.66V, voltage on phase Y is 209.84V and voltage on phase B is 201.05V the load is supplied by phase Yellow. If all phases are within the range the circuit selects the highest phase voltage to supply the load for example if voltage on phase R is 210V, voltage on phase Y is 215V and Voltage on phase B is 220V the Blue phase selected to supply the load. iv But for avoiding switching of relays many times, the phase greater than other phases atleast volts above 3V will be allowed to supply the load. For example, if phase R is 214 V, phase Y is 203.91V and B is 218.41V the load is supplied by Phase B. But for example if phase R becomes 219.95V even if this voltage is greater than phase B, for avoiding switching ON and OFF relays many times the phase B continue to supply the load. And if the allowed phase is missing another phase is automatically selected to supply the load.