The results of an experimental study of the operating characteristics of an electric fan unit with frequency control on a marine vessel

The individual and total capacities of electric drives of fan installations have significant values, which requires monitoring their electrical energy consumption in nominal and start-up operating modes to prevent overloading of the ship's network, the occurrence of power exchange fluctuations between generators, and a decrease in the quality of electricity. High-quality operation of electric drives of fan installations on modern ships is carried out using frequency converters that allow smooth starts, stops and speed control. In the conducted experimental studies, an Optimus Drive AD80-4TD75 frequency converter is used to power an asynchronous fan electric motor, which includes an uncontrolled rectifier and an autonomous inverter. The oscillograms of voltage, current, and electric motor revolutions obtained in the start and braking modes using linear and S-shaped control laws show good results. The use of the S-shaped control law has some advantages over the application of the linear law, because transients are smoother and the electric drive operates more smoothly. The special capabilities of the Optimus Drive AD80-4TD75 frequency converter make it possible to maintain constant pressure and flow in the air duct when using feedback in the electric drive. It is proved that the application of the proportional frequency control law of the supply voltage does not ensure the maintenance of pressure and frequency when changing the position of the air dampers, while the introduction of a constant integration time when using the proportional integral control law ensures stable maintenance of the set values of pressure and flow over the entire range of changes in the position of the air dampers.