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EP-3765342-B1 - SYSTEMS AND METHOD FOR OPTIMIZING ENGINE OPERATIONS IN GENSETS

EP3765342B1EP 3765342 B1EP3765342 B1EP 3765342B1EP-3765342-B1

Inventors

  • PIPER, ERIK L.
  • BOOKS, MARTIN T.
  • BOOTH, RICHARD A.

Dates

Publication Date
20260506
Application Date
20190311

Claims (15)

  1. A control system for a genset (101) that includes an engine (110) and a generator (120), the control system comprising: a controller (170) configured to be coupled to each of the engine (110) and the generator (120), the controller (170) configured to: compare an engine operating parameter value to a load demand value indicative of a load exerted by the generator (120) on the engine (110); determine that the engine operating parameter value fails to match the load demand value; determine an engine operating parameter threshold value at which the engine operating parameter value failed to match the load demand value; set the engine operating parameter threshold value as a maximum allowable engine operating parameter value for the engine (110); and characterized in that : responsive to a determination that the load demand value is greater than the engine operating parameter threshold value, turn off the engine (110).
  2. The control system of claim 1, wherein the controller (170) is configured to adjust the engine operating parameter value so as to match the load demand value as the load demand value changes over time.
  3. The control system of claim 1 or claim 2, wherein the controller (170) is further configured to: maintain the engine operating parameter value below the engine operating parameter threshold value.
  4. The control system of any of claims 1 to 3, wherein the engine operating parameter value comprises at least one of an engine speed, an engine power or an engine torque.
  5. The control system of any of claims 1 to 4, wherein the controller (170) is further configured to: determine a load demand threshold value at which the engine operating parameter value failed to match the load demand value; and set the load demand threshold value as a maximum allowable load demand value for the generator (120); wherein optionally the controller (170) is further configured to: maintain the load demand value below the load demand threshold value.
  6. A system (100), comprising: a generator (120); an engine (110) coupled to the generator (120), the engine (110) configured to provide mechanical power to the generator (120); and the control system of claim 1, the controller (170) being coupled to the engine (110) and the generator (120).
  7. The system (100) of claim 6, wherein the controller (170) is further configured to adjust the engine operating parameter value to match the load demand value as the load demand value changes over time.
  8. The system (100) of claim 6 or claim 7, wherein the controller (170) is further configured to: maintain the engine operating parameter value below the engine operating parameter threshold value.
  9. The system (100) of any of claims 6 to 8, wherein the engine operating parameter value comprises at least one of an engine speed, an engine power or an engine torque.
  10. The system (100) of any of claims 6 to 9, wherein the controller (170) is further configured to: determine a load demand threshold value corresponding to the engine operating parameter value at which the engine operating parameter value failed to match the load demand value, and set the load demand threshold value as a maximum allowable load demand value for the generator (120); wherein optionally the controller (170) is further configured to: maintain the load demand value below the load demand threshold value.
  11. The system (100) of any of claims 6 to 10, wherein the engine (110) is mismatched with the generator (120) such that the engine (110) has at least one of a peak torque, peak power or peak speed which is less than at least one of a peak torque, peak power or peak speed, respectively, of the generator (120).
  12. A method for controlling a genset (101) that includes an engine (110) and a generator (120), comprising: comparing an engine operating parameter value to a load demand value indicative of a load exerted by the generator (120) on the engine (110); determining that the engine operating parameter value fails to match the load demand value; determining an engine operating parameter threshold value at which the engine operating parameter value failed to match the load demand value; setting the engine operating parameter threshold value as a maximum allowable engine operating parameter value for the engine (110); and characterized in that : responsive to the load demand value being greater than the engine operating parameter threshold value, turning off the engine (110).
  13. The method of claim 12, further comprising adjusting the engine operating parameter value to match the load demand value as the load demand value changes over time; and/or. further comprising: maintaining the engine operating parameter value below the engine operating parameter threshold value.
  14. The method of claim 12 or claim 13, further comprising: determining a load demand threshold value corresponding to the engine operating parameter value at which the engine operating parameter value failed to match the load demand value; and setting the load demand threshold value as a maximum allowable load demand value for the generator (120).
  15. The method of claim 14, further comprising maintaining the load demand value below the load demand threshold value.

Description

Technical Field The present invention relates generally to control systems for preventing stalling in engines included in or with generator sets ("gensets"). Background Gensets such as those used in electrified vehicles include an engine coupled to a generator. The generator produces electricity when driven by the engine. Such gensets may be used, for example in hybrid vehicles in which the genset provides intermittent power to drive the vehicle along with a power source (e.g., batteries), or may be used in electric vehicles in range extender electric vehicles (REEV) as an on board source of electrical generation configured to provide electrical power to the vehicle once the primary power source starts to run low. The engine is generally matched to the generator so that the engine can match the load demand exerted by the generator on the engine. Generally, the engines included in gensets have more variation in power production than the generator. For example, a genset may be matched during calibration using a particular engine and generator combination, but when the genset is installed in a system (e.g., a vehicle), a different engine (e.g., a different engine of the same model) is used which may be mismatched with the generator. Furthermore, the engine may have been calibrated to match the generator up to a certain load demand, but due to wear-and-tear during operation, or because of environmental conditions, the engine may become mismatched from the generator. In such instances, the engine may be unable to match the load demand exerted on it by the generator. If the load demand exerted by the generator on the engine exceeds the power which the engine can produce, the engine may stall or lug and eventually shut down. Therefore, gensets are often controlled so as to provide a large buffer between the actual rated power of the engine (e.g., 150 kW) and the load demand that the generator may exert on the engine (e.g., 130 kW) so as to accommodate any mismatch and prevent lugging and stalling. However, this often results in the engine being used below the actual power that the engine may be capable of providing to the generator, thereby reducing the performance of the genset, and the system (e.g., a vehicle) including the genset. WO2012135258 discloses an electric power generation system including an engine, an electrical generator, and a system controller. The engine is configured to produce mechanical power and includes an engine controller and a turbocharger for raising air pressure to a boost pressure. The turbocharger is controlled by the engine controller during steady state operation of the system. The electrical generator is mechanically connected to the engine and converts mechanical power into electrical power. The system controller is configured to receive a signal indicative of an electrical load on the generator. During a transient condition during which the electrical load increases, the system controller is configured to directly control the turbocharger in order to change the configuration of the turbocharger in order to increase boost pressure. US2012306457 discloses a powertrain system which includes an electric machine mechanically coupled to an internal combustion engine mechanically coupled to a transmission. A method for operating the powertrain system includes determining an engine stall threshold rate during engine operation in a low load condition. A time-rate change in an accessory load is controlled by the electric machine operating in an electric power generating mode in response to the engine stall threshold rate during the engine operation in the low load condition. US2010106389 discloses a control system provided for a generator set coupled to supply electrical power to an external load. The control system may have an input device configured to receive input indicative of a desired adjustment to the external load, and a power control device operable to affect a power output of the generator set. The control system may also have a controller in communication with the input device and the power control device. The controller may be configured to determine a change in the power output of the generator set corresponding to the desired adjustment to the external load, and to operate the power control device to implement the change in power output of the generator set before the desired adjustment to the external load is initiated. Further prior art is known from WO2016046613. Summary Embodiments described herein relate generally to systems and methods for preventing stalling and/or lugging in an engine coupled to a generator. Particularly, systems and methods described herein are configured to dynamically determine an engine operating parameter threshold value corresponding to a load demand value exerted by the generator on the engine at which the engine starts to stall, and set the value as a maximum allowable engine operating parameter value. According to a first aspect of the inven