Implementation of a Microcontroler Based Multiple Source Power Supply Selector with Priority Option

Abstract

Increasing global use of technology in everyday chores has raised the need for electric power in our lives the need for constant power thereby becomes very paramount for the smooth running of modern systems. In Nigeria incessant outages have led to failures in systems and sometimes lives, necessitating the use of multiple sources of power for homes, offices and industries, each of which costs differently to use. This work presents the design and implementation of a microcontroller based multiple source power selector with priority selector. The inclusion of priority selection means each source can be selected for use based on its cost or quality/availability. When cost is prioritized by selection then mains power is first selected for use before generator, and when both are absent then solar is optionally available for selection. When uninterruptible power (UP) is prioritized then the source with better quality is selected for use. The three sources are each stepped down using three separate step down transformers, The output of which are rectified and sampled to an ATmega328 microcontroller which is programmed using C++ language to select the most appropriate output based on the Cost or quality/availability, the microcontroller commands relays that perform the switching action i.e. connecting the load to the most appropriate source. The system was simulated in Proteus simulation environment, Simulation result show that in all cases of performance the source that is supplied to the output is based on the priority mode selected. This system can be used in economy mode for homes where cost of power is the criteria while in hospitals the UP-priority mode is recommended because availability is what matters. This device reduces the possibility of complete power outage in the event of a power failure in any specific source. Users can connect their electronic gadgets to the device, which reduces the response time needed to switch from one power source to another.