Pre-unloading power reduction system and method

1. A work machine comprising:

a supporting structure;

a harvester assembly coupled to the supporting structure;

ground engaging mechanisms coupled to the supporting structure;

a tank coupled to the supporting structure and configured to contain harvested crop harvested by the harvester assembly;

an engine configured to drive rotation of the ground engaging mechanisms to move the supporting structure during operation of the work machine;

a controller operatively coupled to the engine, the controller including a memory and a first power curve and a second power curve stored in the memory, the second power curve having a lesser power level relative to the first power curve over a range of engine speeds;

an operator input device operatively coupled to the controller and configured to send signals to the controller;

a crop sensor operatively coupled to the controller and configured to identify an amount of harvested crop in the tank;

wherein the controller is configured to operate the engine, in response to signals received from the operator input device, in: (i) a nominal mode associated with the first power curve; (ii) a reserve mode associated with the second power curve; and (iii) an automatic mode associated with the first power curve and the second power curve;

wherein, in the automatic mode, the controller is configured to change operation of the engine from operation in accordance with the first power curve to operation in accordance with the second power curve in response to at least one sensed factor associated with the harvested crop; and

wherein the at least one sensed factor associated with the harvested crop includes a determination that the amount of harvested crop in the tank is above a predetermined upper threshold crop level.

2. The work machine of claim 1 , wherein the crop sensor is configured to identify a flow rate of harvested crop into the tank; and

wherein the at least one sensed factor associated with the harvested crop further includes the flow rate of harvested crop into the tank.

3. The work machine of claim 1 , further comprising a moisture sensor operatively coupled to the controller and configured to identify the moisture level of harvested crop in the tank;

wherein the at least one sensed factor associated with the harvested crop includes the moisture level of harvested crop in the tank.

4. The work machine of claim 1 , further comprising an unloading device coupled to the engine and arranged to contact harvested crop contained in the tank;

wherein the unloading device is configured to be switched on and off;

wherein the unloading device is configured to remove harvested crop from the tank when switched on; and

wherein, in automatic mode, the controller is configured to change operation of the engine from operation in accordance with the first power curve to operation in accordance with the second power curve prior to the unloading device being switched on.

5. The work machine of claim 4 , wherein the controller includes a third power curve stored in the memory that has a greater power level over the range of engine speeds relative to the first power curve;

wherein the controller is configured to operate the engine in a boost mode associated with the third power curve; and

wherein the controller is configured to change operation of the engine from operation in accordance with the second power curve to operation in accordance with the third power curve when the unloading device is switched on.

6. The work machine of claim 1 , wherein the controller includes a plurality of additional power curves stored in the memory, each additional power curve of the plurality of additional power curves having a power level between that of the first power curve and the second power curve over the range of engine speeds; and

wherein, in automatic mode, the controller is configured to change operation of the engine from operation in accordance with the first power curve to operation in accordance with each additional power curve successively, and subsequently, to operation in accordance with the second power curve in response to at least one sensed factor associated with the harvested crop.

7. The work machine of claim 1 , wherein the harvester assembly is one of: a grain harvester for harvesting grain and a corn harvester for harvesting corn; and

wherein the work machine further comprises a harvester sensor operatively coupled to the controller and configured to identify whether the harvester assembly is a grain harvester or a corn harvester.

8. The work machine of claim 7 , wherein the controller includes a first supplementary power curve and a second supplementary curve stored in the memory, the second supplementary curve power curve having a lesser power level relative to the first supplementary power curve power curve over the range of engine speeds;

wherein the difference in power level of the first supplementary power curve relative to the second supplementary power curve over the range of engine speeds is greater than the difference in power level of the first power curve relative to the second curve over the range of engine speeds;

wherein, in automatic mode, the controller is configured to change operation of the engine from operation in accordance with the first supplementary power curve power curve to operation in accordance with the second supplementary curve power curve in response to at least one sensed factor associated with the harvested crop;

wherein, in automatic mode, in response to determining that the harvester assembly is a grain platform, the controller is configured to operate the engine in accordance with the first power curve and subsequently the second power curve; and

wherein, in automatic mode, in response to determining that the harvester assembly is a corn header, the controller is configured to operate the engine in accordance with the first supplementary power curve power curve and subsequently the second supplementary curve power curve.

9. The work machine of claim 1 , further comprising a weight sensor operatively coupled to the controller and configured to identify the weight of harvested crop in the tank;

wherein the at least one sensed factor associated with the harvested crop includes the weight of harvested crop in the tank.

10. A work machine comprising:

a supporting structure;

a harvester assembly coupled to the supporting structure;

ground engaging mechanisms coupled to the supporting structure;

a tank coupled to the supporting structure and configured to contain harvested crop;

an unloading device that is configured to remove harvested crop from the tank when the unloading device is activated;

an engine coupled to the supporting structure and configured to provide power to the ground engaging mechanisms and the unloading device; and

a controller operatively coupled to the engine and including a memory having a first power curve, a second power curve, and a third power curve stored thereon,

wherein the second power curve has a lesser power level relative to the first power curve over a range of engine speeds, and the third power curve has a greater power level relative to the first power curve over the range of engine speeds;

wherein the controller is configured to change operation of the engine from operation in accordance with the first power curve to operation in accordance with the second power curve in response to at least one sensed factor associated with the harvested crop and, subsequently, to operate the engine in accordance with the third power curve when the unloading device is activated; and

wherein the at least one sensed factor associated with the harvested crop includes the amount of harvested crop in the tank.

11. The work machine of claim 10 , wherein the crop sensor is configured to identify a flow rate of harvested crop into the tank; and wherein the at least one sensed factor associated with the harvested crop further includes the flow rate of harvested crop into the tank.

12. The work machine of claim 10 , further comprising a moisture sensor operatively coupled to the controller and configured to identify the moisture level of harvested crop in the tank; wherein the at least one sensed factor associated with the harvested crop includes the moisture level of harvested crop in the tank.

13. The work machine of claim 10 , further comprising a weight sensor operatively coupled to the controller and configured to identify the weight of harvested crop in the tank; wherein the at least one sensed factor associated with the harvested crop includes the weight of harvested crop in the tank.

14. The work machine of claim 10 , wherein the controller includes a plurality of additional power curves stored in the memory;

wherein each additional power curve of the plurality of additional power curves has a power level between that of the first power curve and the second power curve over the range of engine speeds; and

wherein the controller is configured to change operation of the engine from operation in accordance with the first power curve to (i) operation in accordance with each additional power curve successively and subsequently to (ii) operation in accordance with the second power curve in response to at least one sensed factor associated with the harvested crop.

15. A method of operating a work machine comprising:

operating an engine of the work machine in accordance with a first power curve having a first power level over a range of engine speeds;

determining that a tank configured to contain harvested crop has been filled with harvested crop above a predetermined upper threshold crop level; and

operating the engine of the work machine in accordance with a second power curve having a second power level lesser than the first power level over the range of engine speeds, in response to determining that the tank has been filled with harvested crop above the predetermined upper threshold crop level.

16. The method of operating a work machine of claim 15 , further comprising:

activating an unloading device powered by the engine to remove harvested crop from the tank subsequent to operating the engine of the work machine in accordance with the second power curve.

17. The method of operating a work machine of claim 15 , further comprising:

operating the engine of the work machine, during operation of the unloading device, in accordance with a third power curve having a third power level greater than the first power level over the range of engine speeds.

18. The method of operating a work machine of claim 15 , further comprising:

determining that the moisture level of the harvested crop in the tank is above a predetermined harvested crop moisture level threshold prior to operating the engine of the work machine in accordance with the second power curve; and

wherein operating the engine of the work machine in accordance with the second power curve further includes:

operating the engine of the work machine in accordance with the second power curve in response to determining that the moisture level of the harvested crop in the tank is above the predetermined harvested crop moisture level threshold.