It is considerably easier to analyze a maline power system on one of the simulators and to follow the state changes by the appropriate simulation model. The simulation model does not endanger operating conditions, the parts of the plant (generator) do not suffer significant damage, the test limits can be reached (short circuit), and there is no danger for the lives of the crew and the plant itself. Simulation ensures quantitative analysis of the process, which implies that this process takes place over a period of time, that it includes random variables, and uses system resources and a large number of intenelated elements. Simulation of ce1tain processes will provide us with answers to the questions such as: What if the machine in operation fails? What if the need for greater fuel efficiency increases? ... For certain systems, several methods were used, but they are difficult to compare. When creating the model, only those parameters that contributed to achieving the research objectives were included. Some other parameters were either ignored or their impact reduced to minimum, so that the model could achieve easier solution. The evaluation of simulation models required creation of a series of models. Each of them was created in special conditions. Some of them were even taken as finished and served only as one part in creation of a larger number of simulation models. Larger number of samples leads to better solutions. This paper deals with simulations as well as measurements in the simulator. Creating new models results in optimizing the marine power system and proposing more efficient solutions, with intention to create an environment in which crew can meet the demands of new technologies, to develop guidelines for diagnosis and to create a modem simulator which provides redundancy.