UV Power Supply
To ensure trouble-free operation, the UV is equipped with three independent and one standby power unit for the emergency ascent purposes.
Each power unit operation is absolutely independent from other power units. Each power unit has its own ballast system circuit and is connected to the UV only with a disconnect valve joining the pump-in and pump-out pipelines together. Each power unit is fit with the complete navigation equipment set and the control system. Aboard the base vessel, where they carry out the maintenance and repairs of the power units, there are standby power units – assuming one standby unit per a vehicle.
UV Power Supply System Overview
The power unit is a specially designed structure containing engines, fuel tanks, high pressure pumps, and a control system. Each set is placed within a separate hermetically sealed body and capable of regulating its own operation depending on the necessity.
In the course of designing the power unit, the engineers created special conditions for the engine to operate in a sealed space, and arranged the engines operation system. The mechanical power is transferred to the pumps that either pump out or inject the water to the multitiered ballast system. The operation of each of such power units is absolutely autonomous. Each unit has its own ballast systems loop and connection with the UV by a hydraulic fuse connecting only the pump-out and pump-in pipelines.
The ballast water is pumped into the power unit for transferring the water into the ballast tanks (in the course of immersion), and then in the course of pumping out (in the course of operation and ascending while maneuvering) the water under pressure returns to the power unit and from that point it is transferred with the help of pumps through the pipelines to the points where the mechanical power is needed, and through the turbine that converts the water stream under pressure into the mechanical power and drives, in its turn, the chain ladles for nodules collection and other equipment. The generators convert the required amount of energy to electric power for the control and illumination systems. The advantage of such power unit consists in the fact that all necessary equipment operating under the atmospheric pressure is placed in the protective housing, and only the ballast water is transferred through the valves under pressure, thus transmitting the energy for mechanical operations. After surfacing, the power units are replaced and repaired within a short time.
General view of the power unit in the assembled condition and in the course of repairs and preventive maintenance operations
The power unit structure and technical parameters
UV Operating Motion Devices
For the longitudinal movement of the vehicle in the horizontal plane, 4 propulsion units (propeller engine) are used. They are located in the horizontal cylindrical channels of the left and right sides of the vehicle. The propellers ensure synchronization of the vehicle linear velocity with the angular velocity of rotation of the nodule-mining tool.
To move the vehicle in a vertical plane, 4 propellers are located in the vertical cylindrical channels in the bow and stern of the vehicle.
To keep the vehicle “on track” and to prevent its driftage, another propeller is located in a horizontal channel in the forebody of the vehicle.
The turbine for conversion of the water stream energy to the mechanical power.
UV Hydraulic System
The water from the ballast system is pumped by the hydraulic system of the vehicle. The system includes submersible high-pressure pumps. The pump drives are submersible brushless DC motors. All pipelines have safety valves that control the flow in the hydraulic system.
UV Emergency System
The vehicle ballast system is divided into three independent tiers. Each of the 3 tiers of the ballast system is supplied by separate power units. In case of failure of two of three ballast tiers, the vehicle switches over to positive buoyancy and surfaces. In order to switch the vehicle over to positive buoyancy at full load, 20 cubic meters of positive buoyancy is required.
The vehicle is equipped with an emergency ballast discharge device. In case of failure when the device is submerged, while the pumps do not pump out ballast water and the sensors at a depth of 500 meters to the bottom do not determine the vehicle speed decrease, the front plate is discharged, and the vehicle gets positive buoyancy for the vehicle surfacing.
The emergency power unit technical parameters: