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US 12,515,809 B2Granted
Electrically starting a gas turbine engine
AssigneeROLLS-ROYCE plc
InventorsDavid R. Trainer, Mark Sweet, Matthew S. Cartwright
Life of this patent
Estimating the term…
Abstract
An aircraft power and propulsion system includes a gas turbine engine having first and second spools, the first spool being a starting spool; first and second DC electrical networks having first and second operating voltages; a first electrical machine joined with the first spool, the first electrical machine having first and a second winding sets; a second electrical machine joined with the second spool; a first, second and third AC:DC converter; and a controllable switching arrangement configured so that a connection to an AC-side of the third AC:DC converter is switchable between a winding of the second electrical machine or the second DC electrical network via an inductor.
Claims20
An aircraft power and propulsion system, comprising:
- a gas turbine engine having a first spool and a second spool, the first spool being a designated starting spool;
- a first DC electrical network having a first operating voltage;
- a second DC electrical network having a second operating voltage different from the first operating voltage;
- a first electrical machine mechanically coupled with the first spool, the first electrical machine having a first winding set and a second winding set;
- a second electrical machine mechanically coupled with the second spool;
- a first AC:DC converter, wherein an AC-side of the first AC:DC converter is connected to the first winding set of the first electrical machine, and a DC-side of the first AC:DC converter is connected to the first DC electrical network;
- a second AC:DC converter, wherein an AC-side of the second AC:DC converter is connected to the second winding set of the first electrical machine, and a DC-side of the second AC:DC converter connected to the second DC electrical network;
- a third AC:DC converter, a DC-side of the third AC:DC converter connected to the first DC electrical network;
- a controllable switching arrangement configured so that a connection to an AC-side of the third AC:DC converter is switchable between:
- a winding of the second electrical machine;
- and
- the second DC electrical network via an inductor.
9 more elements
A method of starting a gas turbine engine of an aircraft power and propulsion system, the aircraft power and propulsion system comprising:
- a gas turbine engine having a first spool and a second spool, the first spool being a designated starting spool;
- a first DC electrical network having a first operating voltage;
- a second DC electrical network having a second operating voltage different from the first operating voltage;
- a first electrical machine mechanically coupled with the first spool, the first electrical machine having a first winding set and a second winding set;
- a second electrical machine mechanically coupled with the second spool;
- a first AC:DC converter, wherein an AC-side of the first AC:DC converter is connected to the first winding set of the first electrical machine, and a DC-side of the first AC:DC converter is connected to the first DC electrical network;
- a second AC:DC converter, wherein an AC-side of the second AC:DC converter is connected to the second winding set of the first electrical machine, and a DC-side of the second AC:DC converter connected to the second DC electrical network;
- a third AC:DC converter, a DC-side of the third AC:DC converter connected to the first DC electrical network;
- and a controllable switching arrangement,
- the method comprising:
- receiving, by a control system of the power and propulsion system, a request to start or restart the gas turbine engine;
- controlling the switching arrangement to disconnect the AC side of the third AC:DC converter from the winding of the second electrical machine and to connect the AC side of the third AC:DC converter to the second DC electrical network;
- supplying electrical power from one or more electrical power sources to the first DC electrical network;
- and
- supplying electrical power from the first DC electrical network to the first winding set of the first electrical machine via the first AC:DC converter;
- supplying electrical power from the first DC electrical network to the second winding set of the first electrical machine via the second AC:DC converter by operating the third AC:DC converter and the inductor as a DC:DC converter that converts DC electrical power supplied by the first DC electrical network at the first operating voltage to DC electrical power at the second operating voltage.
13 more elements
A method of starting a gas turbine engine of the aircraft power and propulsion system, the aircraft power and propulsion system comprising:
- a gas turbine engine having a first spool and a second spool, the first spool being a designated starting spool;
- a first DC electrical network having a first operating voltage;
- a second DC electrical network having a second operating voltage different from the first operating voltage;
- a first electrical machine mechanically coupled with the first spool, the first electrical machine having a first winding set and a second winding set;
- a second electrical machine mechanically coupled with the second spool, the second electrical machine having a first winding set and a second winding set;
- a first AC:DC converter, wherein an AC-side of the first AC:DC converter is connected to the first winding set of the first electrical machine, and a DC-side of the first AC:DC converter is connected to the first DC electrical network;
- a second AC:DC converter, wherein an AC-side of the second AC:DC converter is connected to the second winding set of the first electrical machine, and a DC-side of the second AC:DC converter connected to the second DC electrical network;
- a third AC:DC converter, a DC-side of the third AC:DC converter connected to the first DC electrical network;
- a fourth AC:DC converter, wherein an AC-side of the fourth AC:DC converter is connected to the second winding set of the second electrical machine, and a DC-side of the fourth AC:DC converter is connected to the second DC electrical network;
- and
- a controllable switching arrangement,
- the method comprising:
- receiving, by a control system of the power and propulsion system, a request to start or restart the gas turbine engine;
- controlling the switching arrangement to disconnect the AC side of the third AC:DC converter from the first winding set of the second electrical machine and to connect the AC side of the third AC:DC converter to the first winding of the transformer;
- controlling the switching arrangement to disconnect the AC side of the fourth AC:DC converter from the second winding set of the second electrical machine and to connect the AC side of the fourth AC:DC converter to the second winding of the transformer;
- supplying electrical power from one or more electrical power sources to the first DC electrical network;
- and
- supplying electrical power from the first DC electrical network to the first winding set of the first electrical machine via the first AC:DC converter;
- supplying electrical power from the first DC electrical network to the second winding set of the first electrical machine via the second AC:DC converter by operating the third AC:DC converter, the fourth AC:DC converter and the transformer as a DC:DC converter that converts DC electrical power supplied by the first DC electrical network at the first operating voltage to DC electrical power at the second operating voltage.
16 more elements
Dependencies are inferred from the claim text.