The primary purpose of writing this book is to make available to the students, researchers and is prepared for case study projects. To ensure an uninterrupted power supply, power plant equipment must be properly operated. When understanding the dynamic behaviour of a rotating machine in order to make it work smoothly, vibration signatures generated by the machine are an important factor to consider. Many new and used machines of various designs and equipment integrations are used to meet the current demand for electricity. There are 60 and 50 Hz versions of these turbomachines available. The 60 Hz machine must be converted to 50 Hz before it can be used in our country. The rotor dynamics of a system, such as turbine configuration, bearings, couplings, gearboxes, and the correct rotor dynamic analysis of generators, are discussed in this book.This work will be examined to investigate the theoretical aspects and software available, as well as various aspects of the above-mentioned set's design and condition monitoring. As a 50 Hz case study, a typical refurbished 50 MW, 60 Hz turbo generator system set to 50 MW is presented.