Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C9/00—Controlling gas-turbine plants; Controlling fuel supply in air- breathing jet-propulsion plants
  • F02C9/26—Control of fuel supply
  • F02C9/30—Control of fuel supply characterised by variable fuel pump output
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/22—Fuel supply systems
  • F02C7/236—Fuel delivery systems comprising two or more pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C9/00—Controlling gas-turbine plants; Controlling fuel supply in air- breathing jet-propulsion plants
  • F02C9/26—Control of fuel supply
  • F02C9/42—Control of fuel supply specially adapted for the control of two or more plants simultaneously
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2220/00—Application
  • F05D2220/30—Application in turbines
  • F05D2220/32—Application in turbines in gas turbines
  • F05D2220/323—Application in turbines in gas turbines for aircraft propulsion, e.g. jet engines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/84—Redundancy
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2270/00—Control
  • F05D2270/01—Purpose of the control system
  • F05D2270/09—Purpose of the control system to cope with emergencies

Definitions

• TITLE SYSTEM FOR PUMPING AND DOSING A FLUID FOR A TURBOMACHINE AND METHOD FOR CONTROLLING SUCH A SYSTEM
• the present invention relates to a fluid pumping and metering system for a turbomachine, a turbomachine comprising it and a method for controlling such a system.
• turbomachines comprise numerous fluid pumping members, for example a main pumping member of a fuel circuit of a turbomachine, a low-pressure pumping member of a fuel circuit of a turbomachine or a pumping unit of an oil circuit of a turbomachine. These fluid circuits require hydraulic power generation and possibly fluid flow metering.
• the main hydraulic power generation is carried out by means of one or more pumps (so-called high-pressure pump(s)) driven mechanically via the gas generator of the turbomachine.
• the proper functioning of the high pressure pump(s) may require a generation of additional hydraulic power upstream which can be achieved by means of one or more pumps (so-called low pressure pump(s), or "engine booster pump” in English) also driven mechanically via the gas generator of the turbomachine.
• the fuel metering, downstream of the high pressure pumps is generally carried out by a hydraulic device controlled by an electronic controller.
• mechanically driven pumps have many disadvantages. Indeed, the pump(s) is (are) sized for the worst case of operation, for example aged pump, worst conditions of the flight envelope, worst temperature of the fluid...
• the hydraulic power delivered by the pump(s) is generally greater than the current need of the turbine engine, generating a withdrawal of unnecessary mechanical power from the gas generator and a rise in the temperature of the fluid.
• the mass of the mechanical drive (drive gears and gearbox housings) and the hydraulic components or organs themselves (pumps, metering valves, pressure regulator) is significant.
• control and actuation members are generally redundant, unlike the hydromechanical metering members (speed regulator differential pressure, valve).
• hydromechanical metering members speed regulator differential pressure, valve
• a blockage of the metering system leads to a loss of operability of the turbomachine.
• the elimination of the mechanical drive of the oil and fuel pumps is an essential step towards the total elimination of the accessory gearbox of the turbomachines, allowing in particular a gain in the drawing off of mechanical power from the gas generator.
• the turbomachine uses a main high-pressure pump, also called a metering pump, comprising an electric motor to drive it, which ensures both the main generation of hydraulic power and the metering fuel flow.
• a main high-pressure pump also called a metering pump
• these metering pumps also called “motor pumps”
• the present invention aims to remedy at least some of these drawbacks.
• the invention proposes a system for pumping and metering a fluid for a turbomachine comprising a first and a second motor pump for the fluid and an electronic computer configured to determine the flow rate of the fluid to be distributed to the turbomachine, each motor pump comprising a pump and a motor configured to drive the pump, the pumping and metering system being characterized in that the electronic computer comprises a first control loop intended to control at least the first motor-driven pump and a second control loop intended to control at least the second motor-driven pump , and wherein the first motor pump and the second motor pump are arranged in series between a fluid reservoir and a member of the turbomachine to be supplied with fluid.
• the invention proposes an alternative to mechanically driven fluid metering and pressurization systems offering the same level of safety as the latter.
• the invention allows a saving in mass for the pumping and metering system.
• the system for pumping and metering a fluid may comprise one or more of the following characteristics, taken separately from each other or in combination with each other: - the system for pumping and metering a fluid is configured to generate a fluid flow, the fluid being fuel or lubricating oil;
• the fluid pumping and metering system is configured to pressurize the fluid, the fluid being fuel intended to supply a main metering system of the turbomachine;
• the system for pumping and metering a fluid comprises a first non-return device arranged in parallel with the pump of the first motor-driven pump and a second non-return device arranged in parallel with the pump of the second motor-driven pump.
• the present invention also relates to a turbomachine, characterized in that it comprises at least one system for pumping and metering a fluid according to the invention and as described above.
• the present invention also relates to an aircraft comprising at least one such turbomachine.
• the present invention also relates to a method for controlling such a system for pumping and metering a fluid, a first control channel comprising a first acquisition unit, the first control loop of the electronic computer and at least the motor motor of the first motor pump and a second control channel comprising a second acquisition unit, the second control loop of the electronic computer and at least the electric motor of the second motor pump, the method being characterized in that it comprises the steps consisting in: a) authorizing the first control channel comprising the first regulation loop to control at least the first motor pump; b) establishing a hydraulic power or flow setpoint for at least the first motor pump of the first control channel authorized by the first regulation loop from data supplied by at least the first acquisition unit of the first control channel permitted; and c) in the event of failure of at least one element chosen from the list comprising the first acquisition unit, the first regulation loop and at least the electric motor or the pump of the motor pump of the first authorized regulation channel, transfer the control authorization from the first control channel to the second control channel, and establish a hydraulic power or flow setpoint
• the two motor pumps are controlled to both supply the requested flow rate.
• the power required for pumping is distributed between the two motor pumps.
• the other is already controlled at the rotation speed adapted to the flow rate requested. There is therefore no disturbance to the flow rate when the failure occurs. Moreover, it is not even imperative to detect the failure of one motor pump to adapt the control of the other.
• control method according to the invention allows hydraulic flow or power to be shared between the motor pumps, with the advantageous technical effects of allowing optimization of the sizing of the motor pumps, of improving their aging and their response time in the event of failure of an element of the piloting channel with authority.
• the piloting method according to the invention may comprise one or more of the following characteristics, which may be taken alone or in combination with each other:
• each regulation loop of a control channel is intended to control a single electric motor
• each regulation loop of a control channel is authorized to control the first and second electric motors
• the establishment of a flow rate or hydraulic power setpoint comprises a step consisting in establishing a distribution of hydraulic power or flow rate to be supplied to the turbine engine between the two electric motors;
• the first regulation loop and the second regulation loop are adapted to exchange data
• the hydraulic flow or power setpoint is applied in full to the second electric motor ;
• each control channel is adapted to control the first electric motor and the second electric motor
• the first regulation loop is configured to jointly control the first electric motor and the second electric motor according to the flow rate or hydraulic power setpoint established except in case of failure of at least one element of the first authorized piloting channel
• the second regulation loop is connected and configured to jointly control the first electric motor and the second electric motor according to a flow or power setpoint established by the second loop regulation of the second control channel to which the authorization is transferred;
• the flow rate or hydraulic power setpoint is such that the other pump connected to the second electric motor provides the entire flow rate or hydraulic power to the turbomachine;
• control process includes a preliminary step during which, when starting the turbine engine and until idle speed is established, only one pump supplies all of the power to the turbine engine;
• control method includes a step of alternating the pump supplying all of the power requested each time the turbine engine is started; - the distribution of flow or power is established as a function of at least one factor among the operating point of the turbomachine, the state of health of each control loop of the computer, the state of health of each motor pump, the margin at extinction or surge, the current acceleration/deceleration, the power supplied by the turbomachine, the flight conditions;
• control process includes a step for monitoring the efficiency of the electric motors and the pump(s);
• the fluid is fuel or lubricating oil.
• FIG. 1 is a schematic view of a system for pumping and metering a fluid according to one embodiment of the invention
• - Figure 2 illustrates a generalization of a system for pumping and metering a fluid according to the invention adapted to implement a control method according to the invention
• - Figure 3 is a block diagram illustrating steps of an embodiment of a method for controlling a system for pumping and metering a fluid according to the invention
• FIG. 4A illustrates a control method according to a first embodiment of the invention in normal operation
• FIG. 4B illustrates the control method according to the first embodiment of the invention in the event of failure of a channel of the computer;
• FIG. 4C illustrates the control method according to the first embodiment of the invention in the event of a sensor failure
• FIG. 4D illustrates the control method according to the first embodiment of the invention in the event of a motor pump failure
• FIG. 5A illustrates a control method according to a second embodiment of the invention in normal operation
• FIG. 5B illustrates the control method according to the second embodiment of the invention in the event of failure of a channel of the computer
• FIG. 5C illustrates the control method according to the second embodiment of the invention in the event of a sensor failure
• - Figure 5D illustrates the control method according to the second embodiment of the invention in the event of failure of a motor pump
• - Figure 6A illustrates a control method according to a third embodiment of the invention in normal operation
• - Figure 6B illustrates the control method according to the third embodiment of the invention in the event of failure of a channel of the computer
• FIG. 6C illustrates the control method according to the third embodiment of the invention in the event of a sensor failure
• FIG. 7 illustrates an example of a motor pump load law applicable to the control methods of FIGS. 5 and 6 in “all operational” operating mode
• FIG. 8 illustrates an example of the motor pump load law applicable to the control methods of Figures 5 and 6 in the event of failure of one of the motor pumps;
• FIG. 9 illustrates another example of a motor pump load law as a function of the operating phase of the turbine engine for the control methods of FIGS. 5 and 6;
• FIG. 10 illustrates another example of a motor pump load law between starting and idling of the turbomachine for the control methods of FIGS. 5 and 6;
• - Figure 11 illustrates an example of a motor pump load law for the control methods of Figures 5 and 6 in the particular case where there is an emergency power regime.
• the example described relates to a fuel pumping and metering system configured to generate a fuel flow
• this example is not limiting and that the invention also applies to any other generation system hydraulic power of an aeronautical fluid, requiring more or less control precision.
• the invention could apply to a fuel boost pressure generation system located upstream of a main hydraulic power generation system, or to an oil flow generation system used for lubrication or cooling of turbomachines.
• the invention proposes a fluid pumping and metering system, in particular for a turbomachine, comprising two hydraulic fluid pumps, each configured to be driven by an electric motor and to be controlled by a two-channel electronic computer for controlling the electric motors driving the pumps.
• FIG. 1 illustrates an embodiment of a pumping and metering system 300 according to the invention, with two hydraulic pumps 312, 314 arranged in series between a fluid reservoir (fluid inlet) and a component of the turbomachine supply fluid.
• Each pump 312, 314 is driven by a respective and dedicated electric motor, 322, 324.
• the first pump 312 is driven by an electric motor called the first electric motor 322 and the second pump 314 is driven by another electric motor, called second electric motor 324.
• Each hydraulic pump 312, 314 can be, for example, a centrifugal pump or a positive-displacement pump, for example of the gear, vane or gerotor type, or any other pump technology making it possible to generate hydraulic power.
• Each electric motor 322, 324 is powered by an electric power source not shown in Figure 1.
• an electric motor can be integrated into a hydraulic pump.
• Such an assembly is known as a motor pump.
• a motor+pump assembly is designated by the term motor-driven pump.
• two non-return flow devices 326, 328 are provided, such as for example a non-return valve or any other device making it possible to perform this function.
• Each flow check device 326, 328 is arranged in parallel on a respective pump.
• the two valves are arranged in series between the fluid reservoir and the member to be supplied.
• These flow non-return devices 326, 328 make it possible to compensate for any differences in flow between the two pumps, or to ensure a privileged path for the fluid in the event of the stoppage of one of the pumps (bypass) .
• the pumping and metering system 300 further comprises an electronic computer (not shown in Figure 1) to control the electric motors controlling the pump.
• the electronic computer comprises regulation loops independent of each other, supplying a control command or instruction to each electric motor of the pumping and metering system.
• each regulation loop establishes its control setpoint from data supplied by a set of respective sensors.
• Each control channel includes a set of sensors providing input data, a control loop from the electronic computer, an electric motor to a hydraulic pump.
• FIG. 2 illustrates a pumping and metering system 400 according to the invention comprising two electric motors for controlling the distribution of fluid to the member to be supplied, in particular by controlling the flow rate of fluid.
• Each electric motor drives its own pump, the motor+pump assembly being designated by the term motor pump in the following description.
• the pumping and metering system 400 therefore comprises two motor pumps 412, 414.
• the motor pumps 412, 414 are arranged in series as illustrated in FIG. 1.
• Each motor pump, 412, 414 corresponds to its own regulation loop 432, 434 of an electronic computer 430.
• Each regulation loop receives its own data from an acquisition unit, 442, 444, to establish a power setpoint for the associated motor pump, 412, 414.
• the data are those provided by one or more external sensors, and/or by each pump, when the pumps incorporate corresponding electronics.
• the electronic computer 430 comprises a first regulation loop 432 supplying a control command or instruction to the first electric motor of the first motor pump 412 and a second regulation loop 434 independent, providing a control command to the second electric motor of the second motor pump 414.
• the electronic computer 430 is configured to determine the flow rate of the fluid to be distributed by each motor pump from the data acquired by these acquisition units 442, 444, in each of the two regulation loops.
• Such an architecture defines two control channels 452, 454, each having its acquisition unit 442, 444, its control loop 432, 434 of the computer and its motor pump 412, 414.
• a first control channel 452 includes the first acquisition unit 442, the first control loop 432 of the computer and the first motor pump 412.
• a second control channel 454 includes the second acquisition unit 444, the second control loop 434 of the computer and the second motor pump 414.
• Such an architecture of a pumping and metering system according to the invention allows the implementation of an improved control method, integrating failure management satisfying the safety criteria imposed in vehicles in the aeronautical field....
• FIG. 3 illustrates the steps of a control method 500 according to the invention of the pumping and metering system 400 of FIG. 2, in which each regulation loop 432, 434 is intended to control at least one electric motor or motor pump 412, 414.
• the method 500 includes at least the following steps:
• a step 502 authorize a control channel among the first control channel 452 and the second control channel 454 to control at least one of the motor pumps 412, 414.
• this control channel has "full authority” is the only piloting channel that can establish flow rate or hydraulic power setpoints in order to control the motor pump(s) 412, 414 during operation of the turbomachine.
• the regulation loop having authority the regulation loop of the piloting channel having full authority.
• the first steering channel 452 is arbitrarily chosen as the authority channel or the control channel.
• the regulation loop of the authorized piloting channel here the first regulation loop 432 determines, from the acquisition data received, the flow rate of the fluid or the hydraulic power to be supplied to the turbomachine by at least the authorized pilot lane motor pump.
• the first regulation loop 432 then establishes, during a step 508, a flow rate or hydraulic power setpoint for at least the motor pump of the authorized control channel from the flow rate of the fluid or the hydraulic power determined.
• the piloting authorization is transferred to the other piloting channel, here the second piloting channel 454, during a step referenced 510.
• the first piloting channel 452 no longer has the authority to pilot the or motor pumps.
• Only the second control channel 454 has "full authority" and can establish hydraulic flow or power setpoints in order to control the motor pumps 412, 414 during operation of the turbomachine.
• FIG. 4 to 6 illustrate three embodiments of this piloting method. More specifically, each FIG. 4 to 6 illustrates a decision matrix corresponding to an embodiment of the control method, these decision matrices illustrating normal operation of the control channel having authority and three different cases of failure that may occur in this channel. piloting.
• each control loop 432, 434 is intended to drive a single electric motor or motor pump 412, 414.
• the regulation loops 432 and 434 of the computer advantageously communicate with each other by a so-called “interchannel” connection 460 between the two regulation loops, allowing a exchange of data between the two control channels.
• the third embodiment of the invention illustrated in Figure 6 corresponds to an improved control method in which each control loop 432, 434 is authorized to jointly and directly control the two motor pumps 412, 414 of the system.
• control channel having authority is the control channel whose regulation loop is represented in bold lines.
• FIGS. 4A to 4D illustrate a decision matrix of a first embodiment of the steering method in which each regulation loop 432, 434 is intended to drive a single electric motor or motor pump 412, 414.
• FIG. 4A represents the case of normal operation in which all the elements of the control channel are operational, that is to say all the elements of the first piloting channel 452 which in this illustrated example has authority.
• the second control channel 454 is on standby or “stand-by”.
• saying that the control channel 454 is on stand-by means that the output signal from the regulation loop 434 is not applied to the second motor pump 414, as shown by a switch in the open position.
• the second control loop 434 does not have the authority to control the second motor pump 414.
• the first motor pump 412 provides all of the flow rate or the hydraulic power requested by the turbine engine, on power or flow set point established by the first control loop 432 of the control channel which has authority.
• the control channel in control In the event of a failure in the channel in control, that is to say the control channel which has authority (regulation loop in bold in the figures), whether it is a failure of the regulation loop 432 (FIG. 4B) , of the acquisition unit 442 or of one of its essential sensors (FIG. 4C) or of the motor pump 412 (motor and/or pump) (FIG. 4D) of the channel in control: there is switching of the channels of piloting in standby and in control.
• the control authorization is transferred from the first control channel 452 to the second control channel 454.
• the first control channel 452 is then on hold as shown by a switch in the open position at the output of the first loop regulation 432 while the switch at the output of the second regulation loop 434 is in the closed position.
• the second control channel 454 has full authority to control the second motor pump 414 by establishing a flow rate or hydraulic power setpoint from the data transmitted by the second acquisition unit 444.
• the second regulation loop 434 drives the motor pump 414 which then supplies all of the hydraulic power required for the operation of the turbomachine.
• this step of transfer of authority or switching of piloting channel in the event of failure of an element of the piloting channel having authority can lead to a non-negligible transient state, due to the time necessary for the second motor pump 414 to take over the entire power load hitherto carried out by the first motor pump 412.
• this method responds to a philosophy of piloting and therefore of managing breakdowns of current aeronautical turbomachines in a piloting channel having a regulation loop having piloting authority only over a single motor-driven pump.
• FIGS. 5A to 5D represent a decision matrix corresponding to a second embodiment of the control method of FIG. 3, advantageously making it possible to reduce the duration of the transient state.
• This second embodiment is particularly suitable for pumping and metering systems in which the two regulation loops 432, 434 of the electronic computer 430 are adapted to exchange data via a so-called "interchannel" link 460.
• the data exchanged are measurements or diagnostic data provided by the acquisition units 442, 444 or else a setpoint established by a regulation loop of the piloting channel in control to pilot the motor pump of the other piloting channel.
• the piloting channel having authority receives data both from the first acquisition unit 442 and from the second acquisition unit 444. Then the regulation loop 432 of the first control channel 452 (having authority) determines from these data the flow rate of the fluid or the hydraulic power to be supplied to the turbine engine by each of the motor pumps 412, 414 (step 506 of FIG. 3) and establishes a flow rate or hydraulic power setpoint for each motor pump 412 , 414 in order to be able to control them simultaneously for the operation of the turbine engine (step 508 of FIG. 3).
• the regulation loop 432 of the first control channel 452 determines a distribution of the flow rates or hydraulic powers to be supplied to the turbomachine by each electric motor or motor pump 412, 414, based in particular on the data exchanged between the two regulation loops via the interchannel link 460.
• the second regulation loop 434, of the standby control channel 454, can in this case be enabled to control the second motor pump 414, with limited authority, to supply part of the hydraulic flow or power necessary for the turbomachine.
• limited authority it is meant that the second control loop 434, of the standby control channel 454, controls the second motor pump 414 from the set point established by the first control loop 432 of the first control channel 452 (having full authority).
• the second control loop 434, of the standby control channel 454 does not establish the setpoint for controlling the second motor pump 414, it receives it from the first control loop 432.
• the control channel having authority is the first control channel 452 (shown in bold) which determines the total flow rate or total hydraulic power necessary for the turbomachine and distributes it between the two motor pumps 412, 414 active.
• the second control loop 434 of the second control channel 454 is on standby, with a "limited authority", to transmit the flow rate or hydraulic power setpoint established by the first regulation loop 432 to the second motor pump 414 in order to control it.
• the second regulation loop 434 (“having authority”) establishes a setpoint in this direction.
• the second motor pump 414 was already in operation or “under load”, it sees a less pronounced transient regime than for the first embodiment of the control method of FIGS. 4A to 4D.
• FIGS. 6A to 6D represent a decision or steering matrix corresponding to a third improved embodiment of the steering method of FIG. 3.
• This third embodiment of the method is particularly suitable for pumping and metering systems in which each control loop 432, 434 is electrically connected to the two motor pumps 412, 414 and enabled to jointly control the two motor pumps 412, 414 of the pumping and metering system.
• the two control loops 432, 434 of the electronic computer 430 can also be adapted to exchange data via a so-called “interchannel” link 460.
• the piloting channel having authority is the first piloting channel 452 whose regulation loop 432 is connected to the two motor pumps 412, 414.
• the first regulation loop 432 determines the flow rate of the fluid or the hydraulic power to be supplied to the turbine engine by each of the motor pumps 412, 414 based on data from at least the first unit acquisition 442.
• the regulation loop 432 of the first control channel 452 (having authority) determines a distribution of the flow rates or hydraulic powers to be supplied to the turbomachine by each electric motor or motor pump 412, 414. Then, it establishes a flow rate or hydraulic power setpoint for each motor pump 412, 414 in order to be able to control them directly and simultaneously for the operation of the turbomachine (step 508 of FIG. 3).
• the second regulation loop 434 of the standby channel 454 does not establish any control setpoint for the motor pumps and does not control any of the motor pumps as schematized by the switches in the open position connected respectively to the first motor pump 412 and to the second motor pump 414 at the output of the second regulation loop 434. That is to say from the regulation loop 432 (FIG. 6B) and/or from the acquisition unit 442 (FIG. 6C), the control authority and consequently the establishment of the flow rate or hydraulic power setpoints are transferred from the first regulation loop 432 to the second regulation loop 434, which becomes the regulation loop of the control channel having authority.
• control loop 434 of the second control channel 454 determines a distribution of the flow rates or hydraulic powers to be supplied to the turbine engine by each electric motor or motor pump 412, 414. Then, it establishes a flow setpoint or of hydraulic power for each motor pump 412, 414 in order to be able to control them directly and simultaneously for the operation of the turbomachine.
• the second regulation loop 434 of the control channel has authority (control channel 454) is capable of establishing a hydraulic flow or power setpoint to control the second motor pump 414, the only functional motor pump, so that it provides the entire flow or the hydraulic power necessary for the operation of the turbomachine.
• the regulation loop 434 is also able to establish a flow rate or hydraulic power setpoint to control the first motor pump 412, the only functional motor pump, so that that it provides all of the hydraulic flow or power necessary for the operation of the turbomachine.
• the first control channel 452 has authority: if one of the motor pumps has a failure, the first control loop 432 of the control channel having authority is able to establish a setpoint in hydraulic flow or power to control the other of the still functional motor pumps, so that the latter provides all of the hydraulic flow or power necessary for the operation of the turbomachine.
• FIGS. 7 and 8 illustrate load laws for the two motor pumps corresponding to the decision matrices of the second and third embodiments of the control method described above (FIGS. 5 and 6) in the case of an equitable distribution of the powers between the two motor pumps: figure 7 for an “all operational” mode of operation and figure 8, in the event of failure of one of the motor pumps.
• FIGS. 7 and 8 illustrate load laws for the two motor pumps corresponding to the decision matrices of the second and third embodiments of the control method described above (FIGS. 5 and 6) in the case of an equitable distribution of the powers between the two motor pumps: figure 7 for an “all operational” mode of operation and figure 8, in the event of failure of one of the motor pumps.
• the flow rate or hydraulic power supplied by the second motor pump becomes zero (curve referenced C24) while the another motor pump 412 takes over and then supplies all of the flow rate or hydraulic power required for the operation of the turbomachine (curve referenced C24).
• Each motor pump is then sized to be able to provide all of the power required by the turbomachine.
• the distribution of flow rate or hydraulic power to be supplied by the two motor pumps can be fair or unspecified.
• one motor pump can provide the power corresponding to the anti-extinguishing flow of the turbomachine and the other the complement.
• the flow distribution can be established according to the operating point of the turbomachine, the state of health of each control loop of the electronic computer, the state of health of each motor pump, the extinction margin or pumping, the current acceleration/deceleration, the power supplied by the turbine engine, the flight conditions or even a combination of all these factors.
• FIG. 9 represents by a graph the evolution of the total hydraulic flow or power (referenced curve C10) available for the turbomachine, the evolution of the hydraulic flow or power of the first motor pump (referenced curve C32), the evolution of the flow or hydraulic power of the second motor pump (curve referenced C34) as a function of the power of the turbomachine, from start-up to the maximum power of the turbomachine when everything is operational and in the case of a static distribution, depending solely on the power of the turbomachine.
• the power supplied by the second motor pump corresponds from idling of the turbomachine to the flow rate or anti-extinction hydraulic power of the turbomachine and the first motor pump supplies the additional flow rate or hydraulic power (curve referenced C34). It is understood that the distribution may depend on the static or dynamic conditions of the operating point mentioned above.
• the method of control according to the invention advantageously comprises a step of alternating the so-called privileged pump each time the turbomachine is started in order to standardize the wear of the two motor pumps.
• the fuel flow requested by the combustion chamber is very low compared to the flow rates requested in flight. Nevertheless, it requires good metering precision to enable the combustion chamber to be ignited under good conditions.
• controlling an electric motor can be tricky at low load.
• the accuracy of a low power pump is difficult to ensure and requires tight manufacturing tolerances, matching or costly adjustments.
• the control method according to the invention comprises a prior step during which, when starting the turbomachine and until a idle speed, only one of the motor pumps supplies the entire flow rate or power required by the turbomachine as illustrated in FIG.
• a start attempt can fail for different reasons. The failure to start may be due to conditions exogenous to the metering and pressurization system, such as, for example, a fault in the ignition system (spark plugs) of the combustion chamber or a breakdown in a fuel distribution valve; or else under endogenous conditions, that is to say that the motor pump used is actually failing to follow the flow setpoint.
• the piloting method according to the invention advantageously comprises a so-called “second chance start” step.
• the computer detects a failed start, it cuts the starting accessories (starter, starter solenoid valve and igniters), waits for the gas generator speed to decrease sufficiently, then makes a second start attempt with the other motor pump, all of this automatically. If indeed the second attempt to start succeeds with this other motor pump, this may be a sign of a clear breakdown or a harbinger of degradation of the first motor pump. Provision can then advantageously be made to record corresponding information, as data useful for maintenance.
• each motor-driven pump can be required to supply all of the power demanded by the turbomachine and in particular the maximum power demanded by the turbomachine. , the two pumps and their electric motors are therefore sized accordingly.
• each motor pump of the pumping and metering system is sized to provide only the maximum between: - the maximum flow rate or power required in the configuration where the two turbines are operational (AEO Regime for "Ail Engines Operative” in English),
• control method according to the invention further comprises a step of monitoring or "monitoring" in English of the efficiency of the motor pumps by comparing the power of the electric motor with the speed of rotation of the pump to which it is coupled and the power and/or speed of the motor pump with the power of the turbine. This step makes it possible to monitor the state of health of each motor pump.
• this monitoring step is carried out for the same pump at a given speed or during start-up of the turbine, at low flow rate.
• the diagnosis concerning the state of health of the pump can advantageously be carried out by comparing the efficiency of the two pumps on similar speeds or between each start, if there is an alternation of the motor pumps at start-up.
• the three embodiments of a control method according to the invention as described above can be advantageously implemented by a system for pumping and metering a fluid according to the invention as described above.
• the second and third embodiments (FIGS. 5 and 6) of the control method according to the invention also allow hydraulic flow or power to be shared between the motor pumps, with the advantageous technical effects of allowing optimization of the sizing of the motor pumps, improve their aging and their response time in the event of failure of an element of the control channel having authority.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Control Of Non-Positive-Displacement Pumps (AREA)
• Control Of Positive-Displacement Pumps (AREA)

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• 2022
  • 2022-03-16 EP EP22712994.7A patent/EP4308805A1/de active Pending
  • 2022-03-16 WO PCT/FR2022/050477 patent/WO2022195224A1/fr active Application Filing
  • 2022-03-16 US US18/550,658 patent/US20240159192A1/en active Pending

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