Abstract: A method for minimizing a fuel consumption rate of a vehicle and a method for tracking an optimal state of charge function for a hydrostatic accumulator are provided. The first method includes the steps of providing a motor and pump, determining an efficiency of the motor and pump using an efficiency map, providing a power source, and controlling the motor independent from the pump with a controller. The controller employs the efficiency of the motor and the pump to minimize the fuel consumption rate of the vehicle. The second method includes the steps of determining the optimal state of charge control function, calculating an optimal state of charge of the hydrostatic accumulator, determining a state of charge error, calculating a corrective value, and adjusting a state of a charge based on the corrective value and the state of charge error by adjusting the charge of the hydrostatic accumulator.

Abstract: A method for minimizing a fuel consumption rate of a vehicle and a method for tracking an optimal state of charge function for a hydrostatic accumulator are provided. The first method includes the steps of providing a motor and pump, determining an efficiency of the motor and pump using an efficiency map, providing a power source, and controlling the motor independent from the pump with a controller. The controller employs the efficiency of the motor and the pump to minimize the fuel consumption rate of the vehicle. The second method includes the steps of determining the optimal state of charge control function, calculating an optimal state of charge of the hydrostatic accumulator, determining a state of charge error, calculating a corrective value, and adjusting a state of a charge based on the corrective value and the state of charge error by adjusting the charge of the hydrostatic accumulator.

Abstract: A hydrostatic driveline for a vehicle, a method for minimizing a fuel consumption rate of the vehicle, and a method for tracking an optimal state of charge function for a hydrostatic accumulator are provided. The driveline includes a power source, a drive axle, a first fluid accumulator, a second fluid accumulator, an auxiliary circuit including a first pump drivingly engaged with the power source, and a drive circuit including a second pump drivingly engaged with the power source, a motor drivingly engaged with the drive axle, and a directional valve. The second pump is in fluid communication with the directional valve and the directional valve in fluid communication with the first fluid accumulator and the second fluid accumulator. The directional valve may be selectively controlled to direct fluid from the second pump and the motor to the first fluid accumulator and the second fluid accumulator.