US 11,988,156 B2
Engine assembly and method of operation
Peter Schober, Kleinmachnow (DE)
Assigned to ROLLS-ROYCE DEUTSCHLAND LTD & CO KG, Blankenfelde-Mahlow (DE)
Appl. No. 17/416,037
Filed by Rolls-Royce Deutschland Ltd & Co KG, Blankenfelde-Mahlow (DE)
PCT Filed Dec. 12, 2019, PCT No. PCT/EP2019/084955
§ 371(c)(1), (2) Date Jun. 18, 2021,
PCT Pub. No. WO2020/126848, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 10 2018 222 890.6 (DE), filed on Dec. 21, 2018.
Prior Publication US 2022/0065176 A1, Mar. 3, 2022
Int. Cl. F02C 9/26 (2006.01); F01D 15/10 (2006.01); F02C 6/14 (2006.01)
CPC F02C 9/26 (2013.01) [F01D 15/10 (2013.01); F02C 6/14 (2013.01); F05D 2220/323 (2013.01); F05D 2220/76 (2013.01); F05D 2240/128 (2013.01); F05D 2260/42 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A power plant assembly, with
a turbine for driving at least one rotor shaft,
a combustion chamber for generating the driving energy for the turbine,
at least one electric machine, which is coupled to the rotor shaft and which is operable both in a generator mode and in a motor mode, and
at least one energy storage system, which is connected to the at least one electric machine, that stores energy generated by the at least one electric machine in the generator mode of the at least one electric machine,
control electronics which are configured to operate the combustion chamber above a permissible minimum value to ensure that the combustion chamber is operated with a lean fuel-air mixture when demanded power of the power plant assembly is below a minimum power of the turbine needed to maintain a lean-mixture operation of the combustion chamber by determining conditions in the combustion chamber, by determining a minimum power draw to avoid combustion chamber extinction and, by operating the at least one electric machine selectively in the generator mode or in the motor mode, depending on the power to be produced by the power plant assembly, as follows,
in the generator mode, to add to a total power draw on the turbine, when a propulsive power draw on the turbine would otherwise fall below a value to maintain the permissible minimum value, and
in the motor mode, to decrease the total power draw on the turbine, when the propulsive power draw on the turbine is otherwise sufficiently above a value to maintain the permissible minimum value during a decrease in the total power draw on the turbine due to the operation of the at least one electric machine in the motor mode.