Question

5.) (Application): Nowadays, more and more houses have solar panels to compliment the energy supplied by the power system. In several cases, the energy produced by those solar panels is more than what the house needs for its own consumption and thus the house may have the option to give this power to the power system grid. Consider that the power system grid works as a voltage source and the solar panel works as second power source with the same and both will be connected in parallel with the load. Using superposition theorem, discuss how a bad synchronization between the phases of both power supplies may damage generators or electronic converters frequency

Answer 1

Now a days , each and every house has an built - in solar panel in order to satisfy their needs without getting power from grid. If the power generated by the panels is more, the excess power can be stored in batteries and when no solar energy is available the stored power can be given to power grid. According to superposition theorem, in a linear network containing several sources, the overall response in any branch in network equals the algebraic sum of response of each individual source considered separately with all other sources made inoperative. On synchronizing the panel power with the main power grid, many factors like phase of voltage, frequency etc must be matched. If the phases of both power grid and panel is not matched, then there will be a difference in rotor angle and stator fwx angle which results in high transient torque when synchronized to power grid. This also causes large damage to generator windings