Hybrid turbine starter for a gas turbine engine
View Patent ↗A Hybrid Turbine Starter (HTS) for a gas turbine engine. The HTS has a turbine member, a turbine shaft, an electric machine, and a Power Electronic Converter (PEC). The electric machine has a rotor and an electric machine drive shaft. The PEC has a current sensor, a voltage sensor, and a controller module. The controller module is configured to selectively supply a sequence of electrical pulses to the electric machine.
1 . A Hybrid Turbine Starter (HTS) for a gas turbine engine, the HTS comprising:
a turbine member;
a turbine shaft coupled to the turbine member;
an electric machine having a rotor and an electric machine drive shaft, the electric machine drive shaft being rotatable about a rotational axis and selectively coupled to the turbine shaft; and
a Power Electronics Converter (PEC) module, comprising:
a current sensor configured to provide a current signal indicative of a current supplied to the electric machine from a supply of electrical power;
a voltage sensor configured to provide a direct current (DC) voltage value indicative of a voltage supplied to the electric machine from the supply of electrical power; and
a controller module configured to, during a mode of operation of the electric machine:
supply an electrical power from the supply of electrical power to the electric machine;
receive the current signal and the DC voltage value based on the supply of electrical power to the electric machine; and
based on the current signal and the DC voltage value, determine an instantaneous rotational position of the rotor.
2 . The HTS of claim 1 , wherein the mode of operation is a rotisserie mode of operation and the controller module is configured to:
selectively supply the electrical power from the supply of electrical power in a form of a first electrical pulse of a sequence of electrical pulses to the electric machine;
receive the current signal and the DC voltage value of the first electrical pulse; and
based on the current signal and the DC voltage value, determine a voltage value required to create a next electrical pulse in the sequence of electrical pulses.
3 . The HTS of claim 2 , wherein the next electrical pulse in the sequence of electrical pulses from the first electrical pulses is a second electrical pulse, and the controller module is configured to selectively supply the electrical power from the supply of electrical power in a form of the second electrical pulse to the electric machine.
4 . The HTS of claim 3 , wherein the controller module is configured to:
receive the current signal and the DC voltage value of the second electrical pulse; and
based on the current signal and the DC voltage value of the second electrical pulse, determine a voltage value required to create a next electrical pulse in the sequence of electrical pulses.
5 . The HTS of claim 4 , wherein the PEC is configured to:
selectively supply the first electrical pulse at a first time;
wait a wait time after the first time; and
selectively supply the second electrical pulse at a second time after the first time and the wait time.
6 . The HTS of claim 3 , wherein the PEC is coupled to a temperature sensor that provides a temperature signal indicative of a temperature of the gas turbine engine after shutdown of the gas turbine engine.
7 . The HTS of claim 6 , wherein the controller module is configured to selectively supply the sequence of electrical pulses based on the temperature signal.
8 . The HTS of claim 1 , wherein the mode of operation is a field-oriented mode of operation of the electric machine and the controller module is configured to:
continuously supply the electrical power from the supply of electrical power to the electric machine; and
continuously receive the current signal and the DC voltage value based on the supply of electrical power to the electric machine.
9 . The HTS of claim 8 , wherein after the field-oriented mode of operation, the controller module is configured to operate the electric machine according to a rotisserie mode of operation of the electric machine by:
selectively supplying a sequence of electrical pulses from the supply of electrical power to the electric machine;
receiving the current signal and the DC voltage value for each respective electrical pulse of the sequence of electrical pulses; and
based on the current signal and the DC voltage value, determining an instantaneous rotational position of the rotor after each respective electrical pulse of the sequence of electrical pulses.
10 . The HTS of claim 1 , further comprising an electric machine clutch configured to selectively couple the electric machine drive shaft to the turbine shaft.
11 . The HTS of claim 10 , wherein the controller module is configured to actuate the electric machine clutch such that that the electric machine clutch is engaged with the turbine shaft.
12 . The HTS of claim 1 , further comprising a housing defining an interior with the electric machine and the turbine member being located within the interior.
13 . The HTS of claim 1 , wherein the controller module is configured to selectively couple the supply of electrical power to the electric machine after shutdown of the gas turbine engine.
14 . The HTS of claim 13 , wherein after shutdown of the gas turbine engine and before selectively coupling the supply of electrical power to the electric machine, the controller module is configured to determine if the supply of electrical power is accessible to the HTS.
15 . The HTS of claim 1 , wherein the supply of electrical power is an on-board supply of electrical power that is permanently accessible to the HTS.
16 . The HTS of claim 1 , wherein the supply of electrical power is an off-board supply of electrical power that is accessible to the HTS after or during a shutdown of the gas turbine engine.
17 . A method of operating a Hybrid Turbine Starter (HTS) during a mode of operation, the HTS comprising a turbine member, a turbine shaft coupled to the turbine member, an electric machine having a rotor and an electric machine drive shaft selectively coupled to the turbine shaft, and a Power Electronics Converter (PEC), the method comprising:
supplying, via the PEC, a supply of electrical power to the electric machine;
receiving, via the PEC, a current signal from a current sensor indicative of a current being supplied to the electric machine from the supply of electrical power;
receiving, via the PEC, a direct current (DC) voltage value from a voltage sensor indicative of a voltage being supplied to the electric machine from the supply of electrical power; and
based on the current signal and the DC voltage value, determining, via the PEC, a rotational orientation of the rotor.
18 . The method of claim 17 , wherein the mode of operation is a rotisserie mode of operation and the method further comprises:
selectively supplying, via the PEC, the supply of electrical power in a form of a first electrical pulse of a sequence of electrical pulses to the electric machine;
receiving, via the PEC, a current signal from a current sensor indicative of a current of the first electrical pulse;
receiving, via the PEC, the DC voltage value from a voltage sensor indicative of a voltage being supplied from a supply of electrical power; and
based on the current signal and the DC voltage value, determining, via the PEC, a voltage value required to create a next electrical pulse in the sequence of electrical pulses.
19 . The method of claim 18 , wherein the next electrical pulse in the sequence of electrical pulses from the first electrical pulses is a second electrical pulse, and the method further comprises selectively supplying, via the PEC, the supply of electrical power in a form of the second electrical pulse to the electric machine.
20 . The method of claim 19 , further comprising:
receiving, via the PEC, a current signal from the current sensor indicative of a current of the second electrical pulse;
receiving, via the PEC, a direct current (DC) voltage value from the voltage sensor; and
based on the current signal and the DC voltage value of the second electrical pulse, determining, via the PEC, a voltage value required to create a next electrical pulse in the sequence of electrical pulses.