Autonomous voltage inverters in the electrical supply systems of underwater objects

Reducing energy losses in autonomous voltage inverters and reducing thermal loads on power switches is becoming particularly relevant in electrical supply systems for underwater facilities. This is due to the difficulty of removing heat from the power elements located in the robust housings of the device and having a number of layout limitations. The use of resonant circuits with constant tuning is limited, since the process of contactless energy transfer is accompanied by a wide range of changes in the load of the inverter, which is associated with possible axial displacements of the primary and secondary parts of the transformer, as well as a change in the gap between these parts when the device is automatically moored to the bottom mooring device. A significant reduction in switching losses in the inverter can be achieved by combining the soft switching mode with minimizing the current of the opposing diodes with a corresponding change in the switching frequency. This property is implemented in the proposed control method. The research of an autonomous voltage inverter on a computer model confirmed the high efficiency of the proposed method for generating inverter control signals. Switching losses in the inverter have been reduced tenfold compared to both conventional control with hard switches and soft switches with constant tuning of the resonant circuit. This property is maintained over a wide range of load variations of the inverter. Solutions to reduce switching losses in contactless energy transmission systems will be useful in power supply systems via a ROV cable line or other tethered underwater facilities as ways to increase the overall efficiency of underwater robotics systems.