Unit for generating non-propulsive electrical power

Abstract

A unit (1, 10, 100) for generating non-propulsive electrical power for use on board an aircraft, the unit (1, 10, 100) comprising an electricity production device (3, 30) comprising a gas turbine (31) and an electricity generator (32) mechanically connected to an outlet shaft (33) of the gas turbine (31), said electricity generator (32) including output electrical connections (320) for being electrically connected to an electrical power supply network (2, 20, 200) on board an aircraft. The unit (1, 10, 100) includes energy storage means (5) and regulator means (6) configured to control the speed of rotation of the gas turbine (31) as a function of the electrical power required by the on-board electrical power supply network (2, 20, 200).

Claims

1. A unit for generating non-propulsive electrical power for use on board an aircraft, the unit comprising: an electricity production device including a gas turbine, and an electricity generator mechanically connected to an outlet shaft of the gas turbine, said electricity generator including output electrical connections to be electrically connected to an electrical power supply network on board the aircraft; energy storage means comprising a battery; regulator means configured to control the speed of rotation of the gas turbine as a function of the electrical power required by the on-board electrical power supply network, the regulator means receiving feedback from the on-board electrical power supply network to control the speed of rotation of the gas turbine as the function of the electrical power required by the on-board electrical power supply network; second power converter means connected between the energy storage means and the electricity production device, the second power converter means comprising a mechanical transmission gearbox coupled to the outlet shaft of the gas turbine and including a mechanical coupling shaft, and an electrical machine mechanically coupled to the mechanical transmission gearbox via the mechanical coupling shaft and electrically coupled to electrical terminals of said energy storage means; and power management means comprising a first module configured, in a first mode, to cause at least part of power produced based on operation of the electricity production device to be recovered and stored in said energy storage means, and a second module configured, in a second mode, to cause the on-board electricity power supply network to be powered by both electricity produced from the gas turbine and energy from the energy storage means when electricity required by the on-board electricity power supply network is greater than a predetermined threshold, wherein the power management means is configured to actuate the first module when the speed of rotation of the gas turbine is at a maximum and the level of charge in the energy storage means is below a charge threshold so that the electrical machine delivers energy to the energy storage means, and actuate the second module when electricity required by the on-board electricity power supply network is greater than the predetermined threshold by using the enemy stored by the energy storage means to operate the electrical machine to rotate the outlet shaft of the gas turbine via the mechanical transmission gearbox and the mechanical coupling shaft so as to assist acceleration of the gas turbine.

2. The unit according to claim 1, wherein the regulator means are configured to cause an increase in the speed of rotation of the gas turbine to a speed higher than that required for generating the electrical power required by the on-board electrical power supply network, the power management means actuating the first module so as to recover the excess power for recharging the energy storage means.

3. The unit according to claim 1, wherein the electricity production device includes first power converter means, said output electrical connections of the electricity generator being to electrically connect to the on-board electricity power supply network via the first power converter means.

4. The unit according to claim 1, wherein the second power converter means further comprise a power converter, the electrical terminals of the energy storage means being electrically connected to said electrical machine via the power converter.

5. An aircraft including comprising: a unit for generating non-propulsive electrical power coupled to an on-board electricity power supply network, the unit comprising an electricity production device comprising a gas turbine and an electricity generator mechanically connected to an outlet shaft of the gas turbine, said electricity generator including output electrical connections for being electrically connected to an electrical power supply network on board the aircraft; energy storage means comprising a battery; regulator means configured to control the speed of rotation of the gas turbine as a function of the electrical power required by the on-board electrical power supply network, the regulator means receiving feedback from the on-board electrical power supply network to control the speed of rotation of the gas turbine as the function of the electrical power required by the on-board electrical power supply network; second power converter means connected between the energy storage means and the electricity production device, the second power converter means comprising a mechanical transmission gearbox coupled to the outlet shaft of the gas turbine and including a mechanical coupling shaft, and an electrical machine mechanically coupled to the mechanical transmission gearbox via the mechanical coupling shaft and electrically coupled to electrical terminals of said energy storage means; and power management means comprising a first module configured, in a first mode, to cause at least part of power produced based on operation of the electricity production device to be recovered and stored in said energy storage means, and a second module configured, in a second mode, to cause the on-board electricity power supply network to be powered by both electricity produced from the gas turbine and energy from the energy storage means when electricity required by the on-board electricity power supply network is greater than a predetermined threshold, wherein the power management means is configured to actuate the first module when the speed of rotation of the gas turbine is at a maximum and the level of charge in the energy storage means is below a charge threshold so that the electrical machine delivers energy to the energy storage means, and actuate the second module when electricity required by the on-board electricity power supply network is greater than the predetermined threshold by using the energy stored by the energy storage means to operate the electrical machine to rotate the outlet shaft of the gas turbine via the mechanical transmission gearbox and the mechanical coupling shaft so as to assist acceleration of the gas turbine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention can be better understood on reading the following description given by way of non-limiting indication and with reference to the accompanying drawings, in which:

(2) FIG. 1 is a diagram of a unit for generating non-propulsive electrical power on board an aircraft in a first embodiment;

(3) FIG. 2 is a diagram of a unit for generating non-propulsive electrical power on board an aircraft in a second embodiment;

(4) FIG. 3 is a diagram of a unit for generating non-propulsive electrical power on board an aircraft in a third embodiment;

(5) FIG. 4 is a diagram of a unit for generating non-propulsive electrical power on board an aircraft in a fourth embodiment;

(6) FIG. 5 is a diagram of a unit for generating non-propulsive electrical power on board an aircraft in a fifth embodiment; and

(7) FIG. 6 is a diagram of a unit for generating non-propulsive electrical power on board an aircraft in a sixth embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

(8) FIG. 1 is a diagram of a unit 1 for generating non-propulsive electrical power on board an aircraft in a first embodiment.

(9) In the first embodiment shown in FIG. 1, the unit 1 is connected to an electricity power supply network 2 on board an aircraft that operates with alternating current (AC) at variable frequency.

(10) The unit 1 comprises an electricity production device 3 comprising a gas turbine 31 and an electricity generator 32. The electricity generator 32 is mechanically connected to the gas turbine 31 via an outlet shaft 33 of the gas turbine 31. The electricity generator 32 is coupled to the outlet shaft 33 via a reduction gearbox (not shown). The electricity generator 32 has three electrical connections 320 each connected to a respective phase of the on-board electrical power supply network 2 in order to supply AC directly to the network 2, with the frequency of the AC delivered by the electricity generator 32 being capable of varying as a function of the load on the network 2.

(11) In a variant, the electricity generator 32 may be coupled directly to the outlet shaft 33 without a gearbox, in particular when electricity generators are used that are capable of operating at the speed of the gas turbine.

(12) The unit 1 also has power converter means 4 and a storage battery 5 having terminals 51. In the first embodiment, the power converter means 4 comprise an AC-DC power converter 41 having three first terminals 411 connected to the three electrical connections 320 of the electricity generator 32, and two second terminals 412 connected to the two terminals 51 of the battery 5.

(13) The unit 1 also has regulator means 6 that control the gas turbine 31. The regulator means 6 are configured to regulate the speed of rotation of the gas turbine 31 as a function of the electrical power required by the network 2.

(14) The unit 1 also has power management means 7 comprising a first module 71 configured, in a first mode, to cause at least a portion of the power produced by the electricity production device 3 to be recovered and stored in the battery 5 via the AC-DC power converter 41, and a second module 72 configured, in a second mode, to cause the on-board electricity power supply network 2 to be powered with electricity produced both from the gas turbine 31 and from the battery 5, the power management means 7 being configured to actuate the first module 71 when the speed of rotation of the gas turbine 31 is at a maximum and the level of charge in the battery is less than a charge threshold, e.g. 30% of the maximum charge of the battery 5, and to actuate the second module 72 when detecting variation in the electricity required by the on-board network 2. The power management means 7 may decide to accelerate the electricity production device 3 to a level greater than that required by the network 2 in order to bring the level of charge to the value needed for the second mode of powering the electricity network 2 to be functional.

(15) FIG. 2 is a diagram of a unit 10 for generating non-propulsive electrical power on board an aircraft in a second embodiment.

(16) Elements identical to the first embodiment are given the same numerical references.

(17) In the second embodiment, the electricity power supply network 20 on board the aircraft is a direct current (DC) network.

(18) In order to power the DC network 20 of the aircraft, the unit 10 of the second embodiment differs from the unit 1 of the first embodiment in that the electricity production device 30 also includes an AC-DC power converter 9 having first terminals 91 that are electrically connected to the three electrical connections 320 of the electricity generator 32, and two second terminals 92 each coupled to a respective one of the two lines of the network 20.

(19) The generator 32 is thus not electrically connected directly to the network 20.

(20) The power converter means 40 of the unit 10 in the second embodiment further comprise a DC-DC power converter 42 having two first terminals 421 electrically connected to the two second terminals 92 of the AC-DC power converter 9 of the electricity production device 30, and two second terminals 422 electrically connected to the two terminals 51 of the battery 5. The AC-DC power converter 42 is configured to modulate the direct current between the battery 5 and the network 20.

(21) In possible variants of the first and second embodiments, not only does the electricity converter that is optionally provided in the electricity production device 3 enable the electricity delivered by the electricity production device to be adapted, but also the unit 1 or 10 can further comprise additional power converter means connected between the output terminals of the electricity production device 3 or 30, i.e. the electrical connections 320 of the electricity generator 32 or the second terminals 92 of the power converter 9, and the lines of the power supply network 2 or 20. These additional power converter means thus serves to adapt the electricity delivered to the network from the electricity delivered by the electricity production device. The characteristics of the electricity produced by the electricity generator can thus be maintained at the same values by using additional power converter means between the electricity production device and the network.

(22) Thus, the additional power converter means may be an AC-AC, an AC-DC, a DC-AC, or a DC-DC power converter.

(23) In addition, depending on the variant, the electricity generator of the electricity production device 3 or 30 may be a DC generator or an AC generator.

(24) Thus, depending on the type of electricity generator, the power converter of the electricity production device may be a power converter that is AC-AC, AC-DC as in the second embodiment, DC-AC, or DC-DC.

(25) FIG. 3 is a diagram of a unit 100 for generating non-propulsive electrical power on board an aircraft in a third embodiment.

(26) Elements that are identical to the first embodiment are given the same numerical references.

(27) In the third embodiment, the electricity power supply network 200 on board the aircraft is an AC network at constant frequency.

(28) To power the constant frequency AC network 200 of the aircraft, the unit 100 of the third embodiment differs from the unit 1 of the first embodiment in that the battery 5 has two first terminals 51 and two second terminals 52, and, as in the second embodiment, the electricity production device 30 includes an AC-DC power converter 9 having first terminals 91 that are electrically connected to the three electrical connections 320 of the electricity generator 32 and two second terminals 92 of the AC-DC power converter 9 that are coupled to the terminals 51 of the battery 5.

(29) The generator 32 is thus not electrically connected directly to the network 200.

(30) In addition, in the third embodiment, the unit 100 has an output AC-DC power converter 8 having two first terminals 81 coupled to the two second terminals 52 of the battery 5 and three second terminals 82 electrically connected to respective ones of the three phases of the three-phase network 200. The output AC-DC power converter 8 is configured to deliver AC at the constant frequency of the network 200 from the DC delivered by the battery 5.

(31) The two second terminals 52 of the battery 5 may be the same as the two first terminals 51 of the battery 5.

(32) FIG. 4 is a diagram showing a unit 1 for generating non-propulsive electrical power on board an aircraft in a fourth embodiment.

(33) Elements that are identical to the first embodiment are given the same numerical references.

(34) In the fourth embodiment, the electricity power supply network 2 on board the aircraft is a variable frequency AC network.

(35) In order to power the variable frequency AC network 2 of the aircraft, the three electrical connections 320 of the electricity generator 32 of the unit 1 of the fourth embodiment are each connected directly to a respective one of the three phases of the network 2, as for the unit 1 of the first embodiment.

(36) The unit 1 of the fourth embodiment differs from the unit 1 of the first embodiment in that the AC-DC power converter 41, and thus the power converter means 4, is replaced by the association of a mechanical power transmission gearbox 43 that is mechanically coupled to the outlet shaft 33 of the gas turbine 31, and an electrical machine 44 that is mechanically coupled to the transmission gearbox 43 via a shaft 45. The unit 1 also has power converter means 4 comprising a transmission gearbox 43 and an electrical machine 44, the electrical machine 44 having two electrical terminals 441 that are electrically connected to the terminals 51 of the battery 5.

(37) The power management means 7 are configured to control the electrical machine 44 so that it delivers electricity to the battery 5 or else takes electricity from the battery 5 in order to deliver additional mechanical power to the outlet shaft 33 of the turbine 31 via the transmission gearbox 43, thereby assisting the gas turbine 31 to accelerate without leading to overheating or other problems.

(38) FIG. 5 is a diagram of a unit 100 for generating non-propulsive electrical power on board an aircraft in a fifth converter.

(39) Elements identical to the fourth embodiment are given the same numerical references.

(40) In the fifth embodiment, the electrical power supply network 200 on board the aircraft is a constant frequency AC network.

(41) In order to power the constant frequency AC network 200 of the aircraft, the unit 100 of the fifth embodiment differs from the unit 1 of the fourth embodiment in that the power converter means 40 further comprises a DC-DC power converter 46 having two first terminals 461 electrically coupled to the two electrical terminals 441 of the electrical machine 44 and two second terminals 462 electrically coupled to the two terminals 51 of the battery.

(42) The DC-DC power converter 46 is configured to modulate the electricity delivered by the battery 5 at a frequency corresponding to the constant frequency of operation of the network 200.

(43) FIG. 6 is a diagram of a unit 10 for generating non-propulsive electrical power on board an aircraft in a sixth embodiment.

(44) Elements that are identical to the fifth embodiment are given the same numerical references.

(45) In the sixth embodiment, the electrical power supply network 20 on board the aircraft is a DC-DC network.

(46) In order to power the DC network 20 of the aircraft, the unit 10 of the sixth embodiment differs from the unit 100 of the fifth embodiment in that the electricity production device 30 of the unit 100 further comprises an AC-DC power converter 9 having three first terminals 91 electrically coupled to the three electrical connections 320 of the electricity generator 32 and two second terminals 92, each electrically connected to one of the two lines of the DC network 20.

(47) In a variant of this sixth embodiment, the unit could include an electricity production device 3 that has only the gas turbine 31 and the electricity generator 32, the unit further including additional power converter means comprising an AC-DC power converter connected between the electricity generator 32 and the DC network 20.

(48) The invention thus makes it possible with various different architectures to provide an auxiliary power unit enabling the consumption of its gas turbine to be limited as much as possible, thereby improving the efficiency with which electricity is produced.