Marine drive unit

Abstract

An electrical drive system for a marine vessel is provided. The system comprises an electric machine arranged below a water level, an inboard electrical energy storage system, wherein the electric machine is connected to the inboard electrical energy storage system via at least one electric cable, and at least one cable cutter arranged to cut the at least one electric cable in the event of impact.

1 . An electrical drive system for a marine vessel, comprising:
 an electric machine arranged below a water level;   an inboard electrical energy storage system, wherein the electric machine is connected to the inboard electrical energy storage system via at least one electric cable; and   at least one cable cutter arranged to cut the at least one electric cable in the event of impact.   
     
     
         2 . The electrical drive system of  claim 1 , further comprising an elongate housing which encapsulates at least an electric motor of the electric machine. 
     
     
         3 . The electrical drive system of  claim 2 , wherein the elongate housing has a distal end portion. 
     
     
         4 . The electrical drive system of  claim 3 , wherein the distal end portion is cone-shaped. 
     
     
         5 . The electrical drive system of  claim 1 , further comprising a mechanical switch, wherein the cable cutter is activated by said mechanical switch upon impact. 
     
     
         6 . The electrical drive system of  claim 3 , wherein the switch is arranged in said distal end portion. 
     
     
         7 . The electrical drive system of  claim 1 , further comprising a fixture arranged to connect the electric machine and the inboard electrical energy storage system, wherein the at least one electric cable is arranged in said fixture. 
     
     
         8 . The electrical drive system of  claim 7 , wherein the cable cutter is arranged in said fixture. 
     
     
         9 . The electrical drive system of  claim 7 , wherein the cable cutter is activated once the fixture is deformed due to said impact. 
     
     
         10 . The electrical drive system of  claim 1 , wherein the cable cutter is mechanically driven. 
     
     
         11 . The electrical drive system of  claim 1 , wherein the cable cutter comprises a spring-loaded part. 
     
     
         12 . The electrical drive system of  claim 1 , wherein the cable cutter comprises a guillotine cutter. 
     
     
         13 . The electrical drive system of  claim 1 , wherein the cable cutter is configured to be arranged in a passive state and an active state, wherein the cable cutter is put in the active state in the event of an impact. 
     
     
         14 . A marine propulsion system for a marine vessel, comprising an electrical drive system according to  claim 1 . 
     
     
         15 . A marine vessel comprising an electrical drive system of  claim 1  and a marine propulsion system.