Development of In-Phase Bus Transfer Scheme Using Matlab Simulink

Main-tie-main reticulation configuration is used to improve reliability of power supply in power plant unit auxiliary systems due to its redundant characteristic. Two main supplies are used to supply power to two sets of loads respectively, while both supplies serve as back-up supplies to each other in the event that one of the supplies is lost as a result of upstream equipment failure. Combination of various boiler auxiliary loads such as pumps, fans and mill, coupled with slow circuit breaker operating times makes it difficult to guarantee fast bus transfer execution when main power supply is lost. The paper focusses on the design of in-phase bus transfer scheme, which is relatively faster than residual voltage bus transfer scheme; and therefore making it the most preferred back-up transfer scheme to fast bus transfer. The paper also investigates its characteristic and impact on the electrical system as well as the driven load insofar as the transient accelerating current and torque is concerned using Matlab Simulink. The results indicate that in-phase bus transfer process is relatively smooth for the motor and the driven load.