Method for operating a vehicle and for decoupling a hybrid drive train from an energy supply of the vehicle

A system for operating a vehicle including a combustion engine, a first drive shaft, a second drive shaft, a first electric machine selectively coupled to the first drive shaft and coupled to the second drive shaft, a second electric machine selectively coupled to the second drive shaft, a front axle with front driving wheels, a rear axle with rear driving wheels, at least one electric module, at least one primary power transmission device, and at least one secondary power transmission device, wherein the at least one primary power transmission device, in operation, is closed and opened, wherein the at least one secondary power transmission device, in operation, is closed and opened, wherein the at least one primary power transmission device selectively connects the first electric machine to at least one of the driving wheels of a first one of the front axle and the rear axle while the at least one primary power transmission device is closed and separates the first electric machine from the at least one of the driving wheels of the first one of the front axle and the rear axle while the at least one primary power transmission device is open, wherein the at least one primary power transmission device selectively connects the combustion engine and the second electric machine to at least one of the driving wheels of a second one of the front axle and the rear axle while the at least one primary power transmission device is closed and separates the combustion engine and the second electric machine from the at least one of the driving wheels of the second one of the front axle and the rear axle while the at least one primary power transmission device is open, and wherein the at least one secondary power transmission device selectively connects the first electric machine to the combustion engine while the at least one secondary power transmission device is closed and separates the first electric machine from the combustion engine while the at least one primary power transmission device is open, the system comprising:

• a control unit that, in operation, controls performance of a first energy transfer function and a second energy transfer function for the vehicle, when the vehicle is stationary;
• wherein the control unit, while the first energy transfer function and the second energy transfer function are performed, controls the at least one primary power transmission device to separate the first electric machine from the at least one of the driving wheels;
• wherein the control unit, while the first energy transfer function and the second energy transfer function are performed, controls the at least one secondary power transmission device to connect the first electric machine to the combustion engine;
• wherein the control unit, while the first energy transfer function is performed, controls the first electric machine to carry out a generator operation in which mechanical energy of the combustion engine is transformed into electrical energy by the first electric machine and provided to the at least one electric module;
• wherein the control unit, while the second energy transfer function is performed, controls the first electric machine to carry out a motor operation in which electric energy from the at least one electric module is transformed into mechanical energy and provided to the combustion engine.