Air start unit for starting and servicing jet engines in aircraft

Abstract

An air start unit for starting and servicing jet engines in aircraft and other flying machines, wherein at least one compressor is provided for generating air and a power supply for supplying electrical power consumers. The air start unit drives the compressor with at least one electric motor, with the electric motor drawing the electrical energy for operation from a high-voltage battery. The electric motors then in turn drive the compressor, which generates compressed air from ambient air for the purpose of starting and servicing the jet engines in aircraft and other flying machines. With an appropriate battery capacity, the air start unit can also supply power consumer of these aircraft and other flying machines via the power supply.

Claims

1. An air start unit for starting and servicing jet engines of aircraft and other flying machines, the air start unit comprising: at least one compressor configured to produce compressed air; a voltage supply to supply electrical power; wherein the at least one compressor is driven by at least one electric motor; wherein electrical energy for operating the at least one electric motor is supplied from at least one high voltage battery, wherein a voltage converter is provided in the air start unit that converts a high voltage of the at least one high voltage battery to a low voltage, wherein the low voltage is a direct voltage or an alternating voltage, and wherein a low voltage battery is provided in the air start unit and is connected downstream of the voltage converter and upstream of the voltage supply, and wherein the voltage supply is directly connected to the low voltage battery and directly connected to the voltage converter.

2. The air start unit as claimed in claim 1, wherein the electrical energy supplied from the at least one high voltage battery is converted into three-phase electricity for the at least one electric motor by at least one inverter.

3. The air start unit as claimed in claim 2, wherein an air conditioning system is provided in the air start unit that heats and cools the at least one inverter, the at least one high voltage battery, the at least one compressor and the at least one electric motor.

4. The air start unit as claimed in claim 2, wherein the at least one compressor, the at least one electric motor, the at least one inverter, a charging controller, the at least one high voltage battery, an air conditioning system, an oil module, a voltage converter, a low voltage battery and the voltage supply are mounted in the air start unit in modular form and thereby replaceable and configurable to be customer specific.

5. The air start unit as claimed in claim 1, wherein the voltage supply draws electrical energy from the low voltage battery and/or the voltage converter.

6. The air start unit as claimed in claim 1, wherein a charging controller is provided in the air start unit that controls a charging process for the at least one high voltage battery.

7. The air start unit as claimed in claim 1, wherein the at least one compressor comprises an air inlet and at least one air outlet.

8. The air start unit as claimed in claim 1, further comprising an oil module that provides oil supply for elements of the air start unit that require lubrication, the elements including the at least one compressor and the at least one electric motor.

9. The air start unit as claimed in claim 1, wherein the at least one compressor is driven by the at least one electric motor by a belt drive.

10. The air start unit as claimed in claim 1, wherein the at least one compressor is a radial compressor.

11. The air start unit as claimed in claim 1, wherein the at least one compressor includes at least two compressors that are used to produce the compressed air in multiple stages.

12. The air start unit as claimed in claim 1, wherein a housing is disposed around the air start unit, the housing being equipped with sound insulation and/or thermal insulation.

13. The air start unit as claimed in claim 1, wherein a mounting panel is provided on which the air start unit is constructed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

(2) FIG. 1 shows a perspective representation of an air start unit according to the invention, and

(3) FIG. 2 shows a block diagram of an air start unit according to the invention.

DETAILED DESCRIPTION

(4) In FIG. 1, components of an air start unit according to the invention are shown as a perspective representation. For this the components are mounted on a mounting panel.

(5) Two compressors 1 for producing compressed air are mounted on the mounting panel. An electric motor 2 is associated with the compressors 1 in order to drive the compressors 1.

(6) The electric motors 2 shown are implemented here as three-phase motors, for which reason they are supplied with electrical energy by means of inverters 3. The inverters 3 in turn draw the electrical energy thereof from a high voltage battery 5 that is embedded in the mounting panel. The high voltage battery 5 now supplies the inverters 3 with high voltage (HV), for example a direct voltage of 600 Volts. For the description of the present invention, any voltage above the low voltage level is referred to as a high voltage.

(7) The high voltage supplied to the inverters 3 from the high voltage battery 5 is now converted by the inverters 3 into three-phase electricity and supplied to the electric motors 2. The electric motors 2 in turn drive the compressors 1. A belt drive has proved advantageous here, so that the compressors 1 are each driven by the motors 2 by means of a respective belt drive.

(8) In order to be able to charge the high voltage battery 5, a charging controller 4 is shown that comprises electrical connectors in order to supply said connectors with electrical energy from outside the air start unit for charging the high voltage battery 5.

(9) So that the compressors 1 operate frictionlessly, an oil module 7 is provided that supplies the movable parts of the compressors 1 with oil. Also shown is an air conditioning system 6 that controls the air start unit within certain temperature limits. The air conditioning system 6 thus ensures that the air within the air start unit and also the components do not fall below or exceed certain temperature ranges. For this purpose, the air conditioning system 6 is designed to be able to cool and/or heat the air in the air start unit.

(10) FIG. 2 illustrates once again the working principle of the proposed air start unit as a block diagram. The air start unit comprises a high voltage battery 5 that supplies high voltage (HV). The high voltage battery 5 can be charged by a charging controller 4. In this exemplary embodiment, the high voltage that is output is supplied to two inverters 3, which can convert three-phase voltages for two electric motors 2 from the high voltage battery 5. The use of inverters 3 has the further advantage that the starting and stopping process of the electric motors 2 can be optimally controlled by suitable starting up and stopping ramps. For this purpose, the inverter 3 controls the frequencies according to a mathematical function when starting up and stopping the electric motors 2.

(11) Two compressors 1 connected in series are driven by means of the electric motors 2 that are driven in this way, advantageously by means of a belt drive. In this exemplary embodiment the compressors 1 are connected in series in order to enable higher pressures of the compressed air. Normal air is thus supplied via an air inlet 11 to the first compressor 1, which produces compressed air in two stages from the supplied air. The second compressor stage is associated with an air outlet 12, so that the compressed air can be taken from the compressor 1. Jet engines or turbines of aircraft and other flying machines are then driven with said extracted compressed air for starting and servicing.

(12) With universally applicable air start units, it has proved advantageous to first operate two compressors in parallel and to connect a further third compressor downstream (not shown). With this operating principle, the system is fitted with two air outlets 12 in order to be able to transfer the required air flow, for example for starting the one engine with acceptable flow losses. Moreover, for this reason most aircraft are equipped with a plurality of air inlet ports so that the air can be supplied via a plurality of hoses.

(13) Likewise, FIG. 2 shows a voltage converter 8 that converts between the high voltage HV and a low voltage LV. In this exemplary embodiment, the low voltage is implemented as a direct voltage. Furthermore, a low voltage battery 9 that can store the low voltage is provided at the low voltage. A voltage supply 10 is provided for supplying and drawing the low voltage. This enables either the low voltage battery 9 to be charged or low voltage to be taken from the air start unit for operating electrical power consumers in aircraft or other flying machines. The voltage taken is then supplied from the low voltage battery 9 and/or the high voltage battery 5 with the voltage converter 8 connected between. The electrical power consumers of the air start unit are also supplied with the low voltage.

(14) The present invention is not limited to the aforementioned features. Rather, further embodiments are conceivable. Thus, instead of three-phase motors, d.c. motors could also be used as electric motors. In this case, the use of the inverter is dispensed with. It is also possible to use a plurality of high voltage batteries in order to increase either the capacity of the high voltage battery or the voltage that is drawn from the high voltage battery. Furthermore, it is possible to drive the compressors not by means of a belt drive between the electric motor and the compressors, but for example by means of direct drive, with which the compressor is connected to the shaft of the electric motor. In this case, it is also possible to control the revolution rate by means of a gearbox. The high voltage battery and also the compressors are of a modular design, so that depending on the power requirement suitable compressors and high voltage batteries can be used in the air start unit and may be replaced.

(15) The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims