Rotating machine and method for balancing its rotor, computer program

Abstract

The invention relates to a method for balancing the rotor of a rotating machine (1), characterized by a rotor balancing controller (6) capable of regulating the heating power. The method comprises the following steps (E10, E20, E30) for, at each iteration k: measuring, by the sensor (4), an amplitude Vk of a vibration V of the rotor (3) and a phase αk of the vibration V; identifying a value Hk of the adjustment parameter H and a value βk of the adjustment parameter β, located within the stable zone (101) of the prescribed stability map; for which, by the controller (6), heating power is applied via the heat treatment head (7) to the rotor (3) in the presence of the vibration V measured by the sensor (4). Figure 10 is shown for the abstract.

Description

Title of the invention: Rotating machine and method for balancing the rotor thereof, computer program

[0001] The invention relates to a rotating machine, as well as a method for balancing the rotor of the rotating machine.

[0002] The field of the invention relates to all types of rotating machines, in particular high-power rotating machines, such as, for example, steam turbines, hydraulic turbines and primary motor pump units of nuclear power plants for producing electricity. The examples of rotating machines indicated are not limiting.

[0003] One of the problems with rotating machines is that they are subject to vibrations when the rotor of the machine rotates relative to its stator.

[0004] The invention seeks to reduce, or even eliminate, these vibrations.

[0005] Several defects can cause a rotor to vibrate excessively. Mechanical unbalance (or imbalance) of the rotor is the most common defect, because it is impossible to manufacture a perfect rotor, that is, a rotor with a homogeneous distribution of mass around its axis of rotation. Indeed, a non-homogeneous distribution creates a centrifugal force field that causes the vibration of the machine. In addition to unwanted noise, these vibrations can cause deterioration of seals and premature fatigue of the mechanical components constituting the rotating machine, such as ball bearings, couplings or bearing supports. Normally, rotors of rotating machines are balanced during the manufacturing phase to minimize mass imbalance around the axis of rotation and keep vibrations at acceptable amplitudes.Unfortunately, in some machines, the unbalance can change over time in operation, leading to excessive vibrations. This change can be caused by erosion, cavitation phenomena, corrosion, fouling, the so-called "Newkirk" effect or the so-called "Morton" effect.

[0006] Cavitation is a phenomenon caused by the depression of a liquid below its saturated vapor pressure. Vapor bubbles then form transiently before imploding in a manner that can be so violent that the pressure and temperature inside the bubble can reach several thousand bars and several thousand degrees Celsius. The implosion also generates a shock wave in the liquid that can erode solid surfaces, thereby causing a loss of mass, generating the creation of mechanical imbalance.

[0007] Corrosion results from the chemical reaction of a material constituting a part rotating part (rotor, blade, disc, etc.) of the machine with an oxidant. This reaction alters the composition of the material and can cause a loss of material (this is the case of the trailing edges of the blades) consequently leading to the creation of mechanical imbalance.

[0008] The Newkirk effect refers to vibrations induced by rotor deformation following asymmetric heating of the latter. The heating is created by friction between the rotor and a fixed part, for example between the rotor and a seal. This phenomenon can become unstable and lead to vibrations that increase continuously over time. Conventional balancing methods cannot solve the problem posed by the Newkirk effect.

[0009] The Morton effect refers to vibrations induced by rotor deformation following asymmetric heating of the latter. The heating is created by the shearing of the oil in the hydrodynamic bearings. There is then a coupling between the rotor vibrations and the quantity of heat generated by shearing. This coupling can be unstable like the Newkirk effect. Conventional balancing methods cannot resolve the problem posed by the Morton effect.

[0010] When the imbalance generates an unacceptable level of vibration, it is necessary to balance the rotor.

[0011] A conventional method for balancing the rotor consists of adding and / or subtracting masses at specific axial positions of the rotor in order to obtain a symmetrical distribution of mass around the axis of rotation. The disadvantage of the conventional method is that it is expensive and time-consuming, resulting in very high downtime because adding and / or removing masses requires stopping the machine. In addition, the conventional method only allows balancing the rotor for a limited set of operating conditions. For example, the vibration behavior of a steam turbine depends strongly on the rotation speed, the power generated, the temperature of the source of the water supplied to the turbine (water temperature of the river, sea or ocean, which vary according to the seasons), the temperature of the steam and its quality.More specifically, the centrifugal force generated by the mass imbalance around the rotational axis varies with the rotational speed of the rotor. In the majority of cases, balancing is carried out at a single rotational speed which is often the nominal rotational speed, which is the operating speed of the rotating machine. The correction necessary to reduce vibrations at the nominal speed can aggravate vibrations at other operating speeds (for example that of a wind turbine) or during transients of rotational speed increases and decreases.

[0012] As an example, let us take the balancing of the turbo-alternator group of a nuclear power plant. This rotating machine is composed of several coupled rotors ri carefully. Each rotor is balanced after machining at the manufacturer's premises. Assembling the rotors on the operating site generates an imbalance due to coupling imperfections. To correct this type of defect, balancing is carried out at the rotors' nominal rotation speed of 1500 rpm. In many cases, correcting the defect at the nominal speed does not reduce vibrations at other rotation speeds. In addition, the improvement provided by balancing is only effective for a given power or condenser vacuum pressure. Indeed, the characteristics of the aerodynamic flow (pressure, humidity and temperature) of the steam depend on the condenser vacuum pressure. The change in temperature and the thermomechanical deformations of the rotor modify the distribution of masses around the axis of rotation.In addition, erosion of the turbine blades or changes in the thermal state of the machine lead to an imbalance that evolves slowly over time. Therefore, balancing must be carried out when the thermal state of the machine is stabilized. Achieving a stabilized thermal state requires several hours or even several days of operation due to the very high thermal inertia of the rotors. Given these constraints, the use of the above-mentioned conventional method leads to very high unavailability of the turbine and forces the operator to use the machine with a set of parameters of the rest of the installation close to those observed during balancing, which has an adverse impact on the maneuverability of the machine when, for example, it is necessary to modify these parameters in order to adapt the power generated to the demand of the electrical network (load following).Indeed, maneuverability will become an increasingly important issue with the introduction of intermittent renewable energies, requiring us to move beyond nominal parameters.

[0013] Thus, according to the conventional method, today, in the vast majority of cases, the correction of the mass imbalance around the axis of rotation is carried out by adding masses or removing masses at specific axial positions of the rotor. These axial positions are called balancing planes, these planes normally intersecting the axis of rotation. When it exists, a balancing plane most often consists of a set of holes distributed uniformly around the axis of rotation. Masses are placed in these balancing holes to allow the imbalance to be corrected. The number of holes as well as the way in which the balancing planes are placed along the rotor have a direct influence on the quality of the balancing of the machine.

[0014] These known methods require several stops and starts of the machine, which are expensive and time-consuming to implement. In addition, these known methods only allow the rotor to be balanced for a limited set of operating conditions. Furthermore, these known methods have the disadvantage to be intrusive in the rotor. Furthermore, document FR-A-2 303 277 discloses a balancing device for a rotating machine comprising, in order to balance the rotor while it is in operation by imposing a deformation on it by asymmetric thermal effect, a sensor capable of detecting an imbalance of the rotor and a signal transducer associated with this sensor, an energy source, capable of using a laser beam, capable of delivering unilateral energy pulses to a chosen portion of the rotor to cause asymmetric heating thereof, and a control device transmitting the signals from said sensor to the energy source for the purpose of adjusting the angular positions of the energy pulses relative to the rotor, the frequency of these energy pulses being in an integral ratio with the speed of the rotor.

[0015] The balancing device known from document FR-A-2 303 277, however, poses the following problem.

[0016] The balancing device known from document FR-A-2 303 277 is empirical and does not provide a calculation method for correctly adjusting the heating carried out by the energy source in order to obtain balancing of the rotor. Thus, a disadvantage of this is that the adjustment of the heating of the energy source is not precise, leading to uncertainties in obtaining balancing of the rotor. This device cannot solve the problem of vibrations which would be induced by the Newkirk effect or the Morton effect.

[0017] However, the problem is that we are seeking to improve the precision and speed of the adjustment of the energy source leading more reliably to the balancing of the rotor.

[0018] An objective of the invention is to obtain a rotating machine, as well as a method for balancing the rotor thereof, which make it possible to balance the rotor to reduce its vibrations when it rotates, by solving the problem mentioned above and by overcoming the drawbacks mentioned above.

[0019] To this end, a first object of the invention is a method for balancing the rotor of a rotating machine, the rotating machine comprising a stator, the rotor being capable of rotating around an axis of rotation relative to the stator, the rotating machine comprising at least one rotor vibration sensor, the vibration sensor being mounted on the stator, at least one heat treatment head, which occupies a determined angular range of less than 360° around the axis of rotation opposite the rotor, which is without contact with the rotor and which is capable of applying to the rotor without contact with the rotor in the determined angular range a heating power, being mounted on the stator, at least one sensor of angular position in rotation of the rotor around the axis of rotation relative to the stator being mounted on the stator, the machine comprising a rotor balancing controller, characterized in that the rotor balancing controller is able to adjust the heating power P = r ■ H • V eJl} where H is a parameter for adjusting an amplitude of a bending moment of the rotor, created by the heat treatment head, and is a real greater than or equal to zero, [3 is a parameter for adjusting a phase of the heating power, r is a coefficient of sensitivity of bending of the rotor to the heating power applied by the heat treatment head, the coefficient r of sensitivity being pre-recorded in the balancing controller, at least one prescribed stability map of the rotor for at least one determined rotational speed of the rotor around the axis of rotation relative to the stator and for at least one axial position of the heat treatment head, being pre-recorded in the balancing controller and indicating at least one stable zone and at least one unstable zone for pairs of values ​​of H and [3, the stability map being parameterized by a vibration reduction factor Fr determined at least in the stable zone, the method comprising at least the following steps, carried out iteratively during rotation of the rotor around the axis of rotation relative to the stator at the determined rotational speed, for, at each iteration k: during a first step, measuring, by the vibration sensor, an amplitude Vk of a vibration V of the rotor and a phase ak of the vibration V of the rotor with respect to a phase reference according to the equation V — Vk - e^, in a second step, identify a value Hk of the adjustment parameter H and a value [3k of the adjustment parameter [3, which are located in the stable zone of the prescribed stability map and for which F r < 1, by the balancing controller, in a third step, apply the heating power p — r U y ) by the heat treatment head via the controller kkk balancing on the rotor and in the presence of the vibration V measured by the vibration sensor.

[0020] According to an embodiment of the invention, the coefficient r of sensitivity of bending of the rotor to the heating power applied by the heat treatment head is prescribed in the balancing controller as being equal to the ratio of a determined and non-zero real value Pb of the heating power to a measured or calculated value of bending moment of the rotor, caused by the application of the real value of the heating power by the heat treatment head via the balancing controller to the rotor.

[0021] According to one embodiment of the invention, • H - Vk < where Pmax is a maximum, positive, non-zero real value of the heating power.

[0022] According to one embodiment of the invention, the rotor is guided in rotation around its axis of rotation relative to the stator by at least two bearings spaced apart from each other along the axis of rotation, the heat treatment head and the vibration sensor being placed between the bearings, [3k = 0° for the machine whose rotor has a mass overhanging one of the bearings, which is less than an intermediate mass of the rotor located between the bearings and for the machine operating at a rotational frequency of the rotor, which is greater than a frequency of a first bending mode of the rotor.

[0023] According to one embodiment of the invention, the rotor is guided in rotation around its axis of rotation relative to the stator by at least two bearings spaced apart from each other along the axis of rotation, the heat treatment head and the vibration sensor being placed between the bearings, [3k = 180° for the machine whose rotor has a mass overhanging one of the bearings, which is less than an intermediate mass of the rotor located between the bearings and for the machine operating at a rotational frequency of the rotor, which is less than a frequency of a first bending mode of the rotor.

[0024] According to one embodiment of the invention, the first, second and third steps are carried out in an iterative manner for at least one previous iteration k and at least one following iteration k+1, for, during the second step of the following iteration k+1: set by the balancing controller the value Hk+i of the adjustment parameter H such that II __ , nk+i~ rv” / v+1 where Vk+i is the amplitude of the rotor vibration V, having been measured during the first step of the following iteration k+1, y is an iteration adjustment factor, which is a strictly positive real number and less than or equal to 1 and which is pre-recorded in the balancing controller, and identifying by the balancing controller the value j of the adjustment parameter [3 from the prescribed stability map making it possible to obtain the smallest value of the vibration reduction factor Fr among a finite set of determined values ​​of the vibration reduction factor Fr.

[0025] According to one embodiment of the invention, y = 1.

[0026] According to one embodiment of the invention, the first, second and third steps are performed iteratively for at least one previous iteration k and at least one following iteration k+1 until the value Hk+i of the parameter of adjustment H of the following iteration k+l reaches a prescribed threshold Hmax, for: during the second step of the following iteration k+1, adjusting by the balancing controller the value Hk+i of the adjustment parameter H and the value [3k+i of the adjustment parameter [3, with Hk+i equal to a prescribed function, increasing as a function of time up to the prescribed threshold Hmax, apply during the third step of the following iteration k+1, by the heat treatment head via the rotor balancing controller and in the presence of the vibration V measured by the vibration sensor, the heating power p_r. pp .y, °ù Vk+i cst the amplitude of the vibration V of the rotor, having been measured during the first step of the following iteration k+1.

[0027] According to one embodiment of the invention, the prescribed increasing function is a linear ramp increasing as a function of time up to the prescribed threshold Hmax or an affine ramp increasing as a function of time up to the prescribed threshold Hmax.

[0028] According to one embodiment of the invention, the method further comprises the following steps, carried out by the balancing controller before the first, second and third steps: identification of a pair of a target value Hc of the adjustment parameter H and a target value [3C of the adjustment parameter [3, which is located in the stable zone of the prescribed stability map and giving the smallest value of the vibration reduction factor Fr, strictly less than 1, among a finite set of determined values ​​of the vibration reduction factor Fr, identification of a pair of a starting value Hd of the adjustment parameter H and a starting value [3d of the adjustment parameter [3, which is located in the stable zone of the prescribed stability map and for which the vibration reduction factor Fr is strictly less than 1, the starting value Hd of the adjustment parameter H being less than the target value Hc of the adjustment parameter H, identification in the prescribed stability map of a path going from the pair of Hd and [3d to the pair of Hc and [3C by the successive pairs of values ​​of Hk and [3k, which are located in the stable zone of the prescribed stability map, the first, second and third steps being carried out in an iterative manner for the successive pairs of values ​​of Hk and [3k to go from the pair of Hd and [3d to the pair of Hc and [3C.

[0029] According to an embodiment of the invention, the method further comprises, before the first, second and third steps, a step of choosing a total, non-zero duration, tm to go from the pair of Hd and [3d to the pair of Hc and [3C, carried out by the balancing controller.

[0030] According to one embodiment of the invention, the first, second and third steps are performed iteratively for at least one previous iteration k and at least one following iteration k+1, for: if k=0 or Vk+i > Vk, identify by the balancing controller during the second step of the following iteration k+1 the value Hk+i of the adjustment parameter H and the value of the adjustment parameter [3, which are located in the stable zone of the prescribed stability map, and otherwise identify by the balancing controller during the second step of the following iteration k+1 the value Hk+i of the adjustment parameter H and the value of the adjustment parameter [3 with Hk+i= Hk and [3k+i= [3k.

[0031] According to one embodiment of the invention, the machine comprises m rotor vibration sensors c;, which are mounted on the stator, where m is a natural integer greater than or equal to 2 and i is an integer ranging from 1 to m, the method further comprises the following steps, before the first, second and third steps: - during a first preparatory step, measurement of the complex vibration measurement vector 1 7 by the m vibration sensors c;, where is Q , = a, ' the amplitude of the rotor vibrations measured respectively by the vibration sensor c; and is the phase of the rotor vibrations measured respectively by the vibration sensor c;, in a second preparatory step, calculation of the prescribed stability map in association with values ​​of the vibration reduction factor Fr by repeating the following sub-steps for each value of H and / 5 lying in the stable zone of the stability map by the balancing controller: - calculate Qf solution of the system of equations: 5 Qf=Qd with [ |7 Qf = \ qfe J l J i J - calculate the values ​​Fr (H, |3) of the vibration reduction factor Fr such that , . / f ] \ where the matrix S is calculated in the manner F r ( / f,^)=max kM next: — calculate a first matrix A such that A = -M • Q2 + j • Q ■ C + K the machine being represented by a finite element model, comprising finite element models, in which the heat treatment head is located between a node Ng of a mesh of the machine and a node Nd of the mesh of the machine and the vibration sensor is located opposite a node Ne of the mesh of the machine, where M is a prescribed mass matrix of the finite element model of the machine, C being a prescribed damping matrix of the finite element model of the machine, K being a prescribed stiffness matrix of the finite element model of the machine, O is the rotational speed, — calculate a second matrix II of degrees of freedom link, matrix II having the following values: — value 1 in its row tdryl, column tx, — value j in its row tdryl, column ty, — value j in its row tdrxl, column tx, — value -1 in its row tdrxl, column ty, — value -1 in its row tdry2, column tx, — value -j in its row tdry2, column ty, — value -j in its row tdrx2, column tx, — value 1 in its row tdrx2, column ty, — 0 elsewhere, where j is the complex number square root of -1, X is a first direction perpendicular to the axis of rotation, Y is a second direction perpendicular to the first direction X and to the axis of rotation, tx is the index of the degree of freedom of translational displacement along the X direction of node Ne, ty is the index of the degree of freedom of translational displacement along the Y direction of node Ne, tdrxl is the index of the degree of freedom of rotational displacement around the X direction of node Ng, tdryl is the index of the degree of freedom of rotational movement around the Y direction of the node Ng,tdrx2 is the index of the degree of freedom of rotational displacement around the X direction of node Nd, tdry2 is the index of the degree of freedom of rotational displacement around the Y direction of node Nd, , — calculate a third passage matrix R, having m rows and n columns, where i is the index for the rows of the matrix R, as well as respectively for the rotor vibration sensors Ci and ranges from 1 to m, n is the number of degrees of freedom of the finite element model, h is the index for the columns of the matrix R, as well as for the degrees of freedom of movement corresponding to respectively the rotor vibration sensors c; for i ranging from 1 to m, the passage matrix R having the following values: R(i, ti)=l ​​for i ranging from 1 to m, 0 elsewhere, — calculate the matrix E , having m rows and n columns, where E = Æ • - H ■ • A'1 - II) where A1 is the inverse matrix, having been calculated, of the matrix A.

[0032] A second object of the invention is a rotating machine comprising a stator, a rotor capable of rotating about an axis of rotation relative to the stator, at least one vibration sensor of the rotor, the vibration sensor being mounted on the stator, at least one heat treatment head, which occupies a determined angular range of less than 360° around the axis of rotation opposite the rotor, which is without contact with the rotor and which is capable of applying to the rotor without contact with the rotor in the determined angular range a heating power, being mounted on the stator, at least one angular position sensor in rotation of the rotor around the axis of rotation relative to the stator being mounted on the stator, a rotor balancing controller, characterized in that the rotor balancing controller is able to adjust the heating power P = r- H -V eJ P where H is a parameter for adjusting a bending moment amplitude created by the heat treatment head and is a real number greater than or equal to zero, [3 is a parameter for adjusting a phase of the heating power, r is a coefficient of sensitivity of the rotor bending to the heating power applied by the heat treatment head, the sensitivity coefficient r being pre-recorded in the balancing controller, at least one prescribed rotor stability map for at least one determined rotational speed of the rotor around the rotational axis relative to the stator and for at least one axial position of the heat treatment head, being pre-recorded in the balancing controller and indicating at least one stable zone and at least one unstable zone for pairs of values ​​of H and [3, the stability map being parameterized by a vibration reduction factor Fr determined at least in the stable zone, the rotor balancing controller and the vibration sensor being configured to implement at least the following steps, carried out iteratively during rotation of the rotor around the rotational axis relative to the stator at the determined rotational speed, for, at each iteration k: during a first step, measurement, by the vibration sensor, of an amplitude Vk of a vibration V of the rotor and of a phase ak of the vibration V of the rotor with respect to a phase reference according to the equation V = Vk • during a second step, identification of a value Hk of the adjustment parameter H and a value [3k of the adjustment parameter [3, which are located in the stable zone of the prescribed stability map and for which F r < 1, by the balancing controller, during a third step, application of the heating power p _r y by the heat treatment head via the controller / v To the balancing on the rotor and in the presence of the vibration V measured by the vibration sensor.

[0033] A third subject of the invention is a computer program, comprising code instructions for implementing at least the second and third steps of the method for balancing the rotor of a rotating machine as described above, when the computer program is executed on a controller.

[0034] The invention will be better understood on reading the description which follows, given solely by way of non-limiting example with reference to the figures below of the attached drawings.

[0035] [Fig-1] represents a schematic front view of a rotating machine following a embodiment of the invention.

[0036] [Fig.2] represents a schematic front view of the rotor of the rotating machine according to an embodiment of the invention.

[0037] [Fig.3] represents a schematic side view of a rotating machine according to an embodiment of the invention.

[0038] [Fig.4] represents a timing diagram of activation time of a treatment head in the rotating machine according to an embodiment of the invention.

[0039] [Fig.5] represents a schematic front view of a deformation caused by a temperature differential on the rotating machine according to an embodiment of the invention.

[0040] [Fig.6] represents a schematic side view of a rotating machine according to an embodiment of the invention.

[0041] [Fig.7] represents a schematic side view of a rotating machine according to an embodiment of the invention.

[0042] [Fig.8] represents a schematic side view of a rotating machine according to an embodiment of the invention.

[0043] [Fig.9] represents a schematic front view of a rotating machine according to an embodiment of the invention.

[0044] [Fig. 10] represents a flowchart of the balancing method according to the invention.

[0045] [Fig. 11] represents an example of a stability map used in the balancing method according to the invention.

[0046] [Fig. 12] represents another example of a stability map used in the balancing method according to the invention.

[0047] [Fig. 13] represents an example of a finite element model used in the balancing method according to the invention.

[0048] [Fig. 14] represents a flowchart of a first embodiment of the balancing method according to the invention.

[0049] [Fig. 15] represents a flowchart of a second embodiment of the balancing method according to the invention.

[0050] [Fig. 16] represents an example of a function that can be used in the second embodiment of the balancing method according to the invention.

[0051] [Fig. 17] represents a flowchart of a third embodiment of the balancing method according to the invention.

[0052] [Fig. 18] represents a flowchart of a fourth embodiment of the balancing method according to the invention.

[0053] [Fig. 19] represents a flowchart of a fifth embodiment of the balancing method according to the invention.

[0054] In Figures 1, 2, 3, 6, 7, 8 and 9, the rotating machine 1 according to the invention comprises a stator 2 and a rotor 3 capable of rotating relative to the stator 2 around an axis 30 of rotation of this rotor 3. The stator may comprise one or more first electrical windings distributed around the axis 30. The stator 2 is considered to be the fixed part of the rotating machine 1 and may comprise elements other than the first electrical windings, such as a frame or others. The rotor 3 comprises a shaft rotating around the axis 30 of rotation and may comprise one or more magnetic elements and / or second electrical windings, distributed around the axis 30 and fixed to the shaft. The rotor 3 is guided in rotation around its axis 30 by one or more bearings 20 fixed to the stator 2. The rotor 3 may have one or more discs 21 fixed to the shaft.

[0055] In a first case, the rotating machine 1 can operate as an electricity generator, that is to say that the rotor 3 is capable of being fixed to a mechanical rotation source, driving the rotor 3 in rotation around the axis 30 to generate electric current in the first electrical windings of the stator 2. The rotation of the rotor 3 induces a variable magnetic field by its magnetic elements and / or second electrical windings set in rotation. The variable magnetic field induces at the terminals of the first windings of the stator 4 an electric voltage called electromotive force. The stator 4 comprises one or more phases each having one or more connection terminals with the outside, to supply to the outside the electric current produced in the first electrical windings of the stator 4 when the rotor 3 is set in rotation around the axis 30.The rotating machine operating as an electricity generator can be used in a power generation plant. The source of . mechanical rotation can be for example a turbine for a rotating generator machine 1 formed by an alternator or a turbo-alternator. The source of mechanical rotation can be an electric motor, this is the case of a primary motor pump unit of a nuclear power plant for electricity production. The source of mechanical rotation can be driven by hydraulic energy, for example in a hydraulic power plant for electricity production. The source of mechanical rotation can be a combined cycle gas turbine.

[0056] In a second case, the rotating machine 1 can operate as a motor, that is to say that the variable electric current sent from the outside to the first electric windings of the stator 2 drives the rotor 3 in rotation around the axis 30 by means of the magnetic elements and / or second electric windings of the rotor 3.

[0057] On the stator 2 is fixed one (or more) vibration sensors 4 making it possible to provide vibration measurements of the rotor 3. Each sensor has a determined position on the stator 2. The sensor(s) 4 make it possible to measure the vibrations in the radial direction of the rotor 3. The sensors 4 can be distributed in different positions along the axis 30 of rotation and can be aligned in a direction parallel to the axis 30 of rotation. The sensors 4 can be distributed around the axis 30 of rotation. The vibrations measured can be displacements, speeds or accelerations. The vibration sensor 4 can be a displacement sensor, an acceleration sensor, a speed sensor, or others. N denotes the number of vibration sensors 4 used.

[0058] The stator 2 comprises one (or more) sensors 5 of the instantaneous angular position ô in rotation of the rotor 3 around the axis 30 of rotation relative to the stator 2. This sensor 5 of the angular position ô in rotation of the rotor 3 can measure the elapsed time from a time reference and can use the period T necessary for the rotor 3 to perform a complete rotation around the axis 30, to determine at each instant t the instantaneous angular position ô of the rotor 2 from the difference between this instant and this period T, the angular position ô returning for example to zero at each elapsed period. When this sensor 5 measures the angular position of the rotor, it is called multi-top-turn. If the sensor 5 measures only the instants between which the rotor performs a complete rotation, it is called "top-turn". The sensor 5 makes it possible to make the link between the phase of the vibration signals and the angular position of the rotor 3.Sensor 5 also makes it possible to measure the rotation period and therefore the rotation speed of the rotor.

[0059] According to the invention, the stator 2 comprises one (or more) heat treatment heads 7, which occupy a determined angular range 0 (non-zero) of less than 360° around the axis 30 of rotation opposite the rotor 3. The heat treatment head 7 is located at a predetermined and non-zero distance from the circumference 31 of the rotor 3. The heat treatment head 7 may be at a distance or next to the bearing(s) 20 or any part of the stator 2 surrounding the rotor 3 around the axis 30 of rotation. The rotor 3 extends in length along the axis 30 of rotation and may have, for example and in a non-limiting manner, a length of several meters. The heat treatment head 7 is without contact with the rotor 3 and is facing the rotor 3.

[0060] The machine 1 comprises a controller 6 for balancing the rotor 3 by the heat treatment head 7. The vibration sensor 4, the angular position sensor 5 and the heat treatment head 7 are connected to the controller 6. The controller 6 for balancing the rotor 3 may be or comprise one (or more) calculators 61, one (or more) computers, one (or more) processors, one (or more) microprocessors, one (or more) microcontrollers, one (or more) actuators, one (or more) permanent memories 62, one (or more) non-permanent memories 62, one (or more) computer programs.

[0061] The invention is described below with reference to Figures 1, 9 and 10 to 19.

[0062] The heat treatment head(s) 7 is / are capable of applying a heating power P to the rotor 3. The heat treatment head(s) 7 is / are therefore a contactless heating head 7.

[0063] The balancing controller 6 of the rotor 3 is configured to adjust the heating power P such that P=rH-V e'P.

[0064] H and [3 are two parameters for adjusting the heating power P of the heat treatment head(s) 7.

[0065] H is a parameter for adjusting an amplitude of the bending moment created by the heat treatment head 7 and is a real greater than or equal to zero and whose unit is Nm / m (bending moment per unit length). The parameter H for adjusting the amplitude of the bending moment created by the heat treatment head 7 is calculated by the balancing controller 6.

[0066] [3 is a parameter for adjusting a phase of the heating power P. The parameter [3 of adjustment of the phase of the heating power P is calculated by the balancing controller 6.

[0067] r is a coefficient of sensitivity of bending of the rotor 3 to the heating power applied by the heat treatment head 7 and is pre-recorded in the memory 62 of the balancing controller 6. The coefficient of sensitivity of bending of the rotor 3 to the heating power applied by the heat treatment head 7 is prescribed to the balancing controller 6. This coefficient r of sensitivity of bending of the rotor 3 can be equal to the ratio r = — of a determined and non-zero real value Pb, of the power M । P of heating on a value Mi of bending moment of the rotor 3, which was measured or calculated and which is caused by the application of the actual value Pi of the heating power P by the heat treatment head 7 via the balancing controller 6 to the rotor 3. Of course, the coefficient r of bending sensitivity of the rotor 3 to the heating power applied by the heat treatment head 7 could be different from this ratio and depend on other functions of Pi and Mb

[0068] V is a vibration of the rotor 3, measured by the vibration sensor(s) 4.

[0069] The adjustment parameter H of the bending sensitivity of the rotor 3 can be calculated by the balancing controller 6 such that r ■ H ■ V k< Pmax^ where Pmax is a maximum, positive and non-zero real value of the heating power P. Of course, the adjustment parameter H of the bending sensitivity of the rotor 3 could be different.

[0070] As shown by way of example in Figures 11 and 12, in the balancing controller 6 (in the memory 62) is pre-recorded one (or more) prescribed stability map 100 of the rotor 3 for one (or more) determined rotational speed of the rotor 3 around the axis 30 of rotation relative to the stator 2 and for one (or more) axial position of the heat treatment head 7 along the axis 30 of rotation. The prescribed stability map 100 comprises one (or more) stable zone 101 for pairs of values ​​of H and [3 and one (or more) unstable zone 102 for pairs of values ​​of H and [3. For example, in Figures 11 and 12, the stable zone(s) 10 of the stability map 100 and the unstable zone(s) 102 of the stability map 100 are represented as a function of the values ​​of H on the abscissa and as a function of the values ​​of [3 on the ordinate (of course, this could also be the reverse).A stable zone is an area in which the amplitude of vibrations converges to a constant value. An unstable zone is an area in which the amplitude of vibrations increases indefinitely.

[0071] In the stability map 100 (in the memory 62) is also pre-recorded a vibration reduction factor Fr determined at least in the stable zone(s) 101 for the pairs of values ​​of H and [3. The vibration reduction factor Fr is therefore also a parameter of the stability map 100. For example, in FIGS. 11 and 12, the vibration reduction factor Fr is represented by constant value lines (or level line) as a function of certain values ​​of H and [3. There may be, as shown in FIGS. 11 and 12, constant value lines of the vibration reduction factor Fr, which are located partly in the stable zone 101 and partly in the unstable zone 102 (as shown in FIGS. 11 and 12), and / or constant value lines of the vibration reduction factor Fr, which are located entirely in the stable zone 101 (as shown in [Fig.12]), and / or lines of constant value of the vibration reduction factor Fr, which are located entirely in the unstable zone 102 (as shown in [Fig. 11]). There may be in the prescribed stability map 100, as shown in Figures 11 and 12, lines of value . constant of the vibration reduction factor Fr, which are greater than one, a line of constant value of the vibration reduction factor Fr equal to one, and lines of constant value of the vibration reduction factor Fr, which are less than one.

[0072] [Fig. 10] represents a flowchart of the method for balancing the rotor 3 of the rotating machine 1 according to the invention.

[0073] The balancing method according to the invention comprises the following steps E10, E20, E30, which are carried out at each iteration k during the rotation of the rotor 3 around the axis 30 of rotation relative to the stator 2 at the determined rotation speed.

[0074] During the first step E10 of each iteration k, the vibration sensor(s) 4 measures an amplitude Vk of the vibration V of the rotor 3 and a phase ak of the vibration V of the rotor 3 relative to a phase reference according to the equation V = Vk ■ e^.

[0075] During a second step E20 subsequent to the first step E10, the balancing controller 6 identifies a value Hk of the adjustment parameter H and a value [3k of the adjustment parameter [3, which defines a point located in the stable zone 101 of the prescribed stability map 100 in the or one of the stable zones 101 of the prescribed stability map 100. This value Hk of the adjustment parameter H and this value [3k of the adjustment parameter [3 are chosen by the balancing controller 6 in the stable zone 101 of the prescribed stability map 100 so that the corresponding vibration reduction factor Fr in the prescribed stability map 100, corresponding to this value Hk of the adjustment parameter H and to this value [3k of the adjustment parameter [3, is smaller than 1.

[0076] During a third step E30 subsequent to the second step E20, the balancing controller 6 controls the heat treatment head 7 so that the heat treatment head 7 sends (without contact) the heating power n _ u \ r ai+^' ) in the presence of the vibration V measured by the sensor 4 of rk~f 'nk' vk' ev vibrations on the rotor 3.

[0077] This makes it possible to quickly inject this heating power Pk into the rotor 3 to counteract the vibrations, without having to wait for the vibrations to stabilize. The invention thus makes it possible to solve the problem of vibrations which would be induced by the Newkirk effect or the Morton effect.

[0078] In first and second examples of application of the invention, shown in [Fig. 13], the rotor 3 is guided in rotation about its axis 30 of rotation relative to the stator 2 by two (or more than two) bearings 20a and 20b spaced apart from each other along the axis 30 of rotation. In these first and second examples, the heat treatment head 7 and the vibration sensor 4 are placed between the bearings 20a and 20b. In these first and second examples, the rotor 3 of the machine 1 has a mass Mi cantilevered to the left of the left bearing 20b, which is less than the intermediate mass Mo of the rotor 3 located between the left bearing 20b and the right bearing 20a. In these first and second examples, the rotor 3 of the machine 1 has a mass M2 cantilevered to the right of the right bearing 20a, which is less than the intermediate mass Mo of the rotor 3 located between the left bearing 20b and the right bearing 20a.

[0079] In the first example where the rotor 3 rotates around the rotation axis 30 at a rotation frequency greater than a frequency of a first bending mode of the rotor 3 (or critical frequency), the balancing controller 6 chooses the value [3k = 0° of the adjustment parameter [3 during the second step E20. This first example corresponds for example to [Fig. 12]. In the example of [Fig. 12], the rotation frequency of the rotor 3 is equal to 1500 revolutions per minute.

[0080] In the second example where the rotor 3 rotates around the rotation axis 30 at a rotation frequency lower than a frequency of a first bending mode of the rotor 3 (or critical frequency), the balancing controller 6 chooses the value [3k = 180° of the adjustment parameter [3 during the second step E20. This second example corresponds for example to [Fig. 11]. In the example of [Fig. 11], the rotation frequency of the rotor 3 is equal to 1200 revolutions per minute.

[0081] In a first embodiment of the invention, shown in Figure 14, the first, second and third steps E10, E20, E30 are carried out in an iterative manner for at least one previous iteration k and at least one following iteration k+1, so that, during the second step E20 of the following iteration k+1, the balancing controller 6 adjusts the value Hk+i of the adjustment parameter H such that rj _ . ^+l“r.yi+t

[0082] Vk+i is the amplitude of the vibration V of the rotor 3, having been measured during the first step E10 of the following iteration k+1.

[0083] y is an iteration adjustment factor, which is a strictly positive real number and less than or equal to 1 and which is pre-recorded in the balancing controller 6 (memory 62). The iteration adjustment factor F is therefore prescribed to the balancing controller 6. For example, the iteration adjustment factor F may be equal to 1. Of course, the iteration adjustment factor F may be other than 1.

[0084] The balancing controller 6 identifies, during the second step E20 of the following iteration k+1, the value of the adjustment parameter [3 from the prescribed stability map 100 and selects the smallest value of the vibration reduction factor Fr from a finite set EFr of determined values ​​of the vibration reduction factor Fr. This finite set EFr of determined values ​​of the vibration reduction factor Fr has been pre-recorded in the balancing controller 6 (memory 62). This makes it possible to have the fastest possible vibration reduction. to reach with the 7.heat treatment head.

[0085] In a second embodiment of the invention, shown in [Fig. 15], the first, second and third steps E10, E20, E30 are carried out in an iterative manner for at least one previous iteration k and at least one following iteration k+1 until the value Hk+i of the adjustment parameter H of the following iteration k+1 reaches a prescribed threshold Hmax. In the second step E20 of the following iteration k+1, the balancing controller 6 sets the value Hk+i equal to a prescribed function f, this function f being increasing as a function of time up to the prescribed threshold Hmax. In the second step E20 of the following iteration k+1, the balancing controller 6 sets the value [3k+i of the adjustment parameter [3.

[0086] During the third step E30 of the following iteration k+1, the balancing controller 6 controls the heat treatment head 7 so that the heat treatment head 7 sends (without contact) the heating power n — jj at rotor 3 in the presence of the measured vibration V 0+1 -r'Hk+l' v À-+1 ' e by the vibration sensor 4. Vk+i is the amplitude of the vibration V of the rotor 3, having been measured during the first step E10 of the following iteration k+1.

[0087] For example, as shown in [Fig. 16], the prescribed increasing function f is a linear ramp increasing as a function of time up to the prescribed threshold Hmax or an affine ramp increasing as a function of time up to the prescribed threshold Hmax.

[0088] In a third embodiment of the mention, shown in [Fig. 17], the balancing controller 6 further performs the following steps E1, E2, E3 before the first, second and third steps E10, E20, E30.

[0089] During step E1, the balancing controller 6 identifies in the or one of the stable zones 101 of the prescribed stability map 100 a couple Cc of a target value Hc of the adjustment parameter H and a target value [3C of the adjustment parameter [3, which gives the smallest value of the vibration reduction factor Fr, strictly less than 1, among a finite set EFr of determined values ​​of the vibration reduction factor Fr, as shown by way of examples in FIGS. 11 and 12.

[0090] During step E2, the balancing controller 6 identifies in the or one of the stable zones 101 of the prescribed stability map 100 a torque Cd of a starting value Hd of the adjustment parameter H and a starting value [3d of the adjustment parameter [3, for which the vibration reduction factor Fr is strictly less than 1, as shown by way of examples in FIGS. 11 and 12.

[0091] The starting value Hd of the adjustment parameter H may for example be lower than the target value Hc of the adjustment parameter H. This makes it possible to reduce the power required to carry out the balancing.

[0092] During step E3, subsequent to steps E1 and E2, the balancing controller 6 identifies in the or one of the stable zones 101 of the prescribed stability map 100 a path 103 going from the starting torque Cd of Hd and [3d to the target torque Cc of Hc and [3C, this path 103 passing through the successive pairs of values ​​of Hk and [3k, which are located in the or one of the stable zones 101 of the prescribed stability map 100, as shown by way of examples in FIGS. 11 and 12.

[0093] The first, second and third steps E10, E20, E30 are carried out in an iterative manner for the successive pairs of values ​​of Hk and [3k of this path 103 to go from the starting pair Cd of Hd and [3d to the target pair Cc of Hc and [3C.

[0094] During a step E4, the balancing controller 6 can further choose a total, non-zero duration, tm to go from the starting torque Cd of Hd and [3d to the target torque Cc of Hc and [3C by the successive pairs of the values ​​of Hk and [3k.

[0095] In a fourth embodiment of the mention, represented in figure 18, the first, second and third steps E10, E20, E30 are carried out in an iterative manner for at least one previous iteration k and at least one following iteration k+1. The balancing controller 6 examines during the iterations whether k=0 or Vk+i > Vk (step E20' in figure 18). In the case where k=0 or Vk+i > Vk, (case YES in figure 18), the balancing controller 6 identifies during the second step E20 of the following iteration k+1 the value Hk+[ of the adjustment parameter H and the value Y of the adjustment parameter [3, which are located in the or one of the stable zones 101 of the prescribed stability map 100. In the case where k=0 or Vk+i > Vk are not verified (case NO in figure 18), the balancing controller 6 identifies during the second step E20 of the following iteration k+1 the value Hk+i of the adjustment parameter H and the value of the adjustment parameter [3 with Hk+[= Hk and [3k+i= [3k.

[0096] In a fifth embodiment of the invention, shown in [Fig. 19], the machine comprises m sensors c; of vibrations of the rotor 3 (sensors 4), which are mounted on the stator 2. The natural integer m is greater than or equal to 2 and i is an integer ranging from 1 to m. The method further comprises the following steps, before the first, second and third stages E10, E20, E30.

[0097] During a first preparatory step E01, the m vibration sensors Cj measure the complex vibration measurement vector • ] T for i going q, 67½ 1 d; from 1 to m. The vibration sensor c; measures the vibration q forming the component i of this measured vector Qd, where the amplitude of the vibrations of rotor 3 is measured respectively by the vibration sensor c; and the phase ^.of the vibrations of the rotor 3 is measured respectively by the vibration sensor c;.

[0098] During a second preparatory step E02, the balancing controller 6 calculates the prescribed stability map 100 in association with values ​​of the vibration reduction factor Fr by repeating the following sub-steps E021, E022 for each value of H and P lying in the stable zone 101 of the stability map 100. During sub-step E021, the balancing controller 6 calculates the vector Qt solution of the system of equations: 3 • Qf = Qd with [ i T for i ranging from 1 to m. j In sub-step E022, the balancing controller 6 calculates the values ​​Fr(H, |3) of the vibration reduction factor Fr such that . . / l'Ai \ Prior to sub-step E021, the controller \ 1 * > zefM / 6 balancing calculates the matrix S of sub-step E021 by performing the following other steps E0221, E0222, E0223 and E0224.

[0099] During step E0221, the balancing controller 6 calculates a first matrix A such that A = -M • Q2 + j • Q ■ C + K ■

[0100] As shown by way of example in [Fig.13], the balancing controller 6 calculates a finite element model representing the machine 1, in which the heat treatment head 7 is located between a node Ng of a mesh of the machine 1 and a node Nd of the mesh of the machine 1 and in which the vibration sensor 4 is located opposite a node Ne of the mesh of the machine 1.

[0101] M is a prescribed mass matrix of the finite element model of the machine 1 and is pre-recorded in the balancing controller 6 (memory 62). The model can be a one-dimensional finite element model along the axis 30 of rotation, as shown for example in [Fig. 13].

[0102] C is a prescribed damping matrix of the finite element model of the machine 1 and is pre-stored in the balancing controller 6 (memory 62).

[0103] K being a prescribed stiffness matrix of the finite element model of the machine 1 and is pre-recorded in the balancing controller 6 (memory 62).

[0104] £2 is the rotational speed, and can be either prescribed or measured by the sensor 5. In step E0222, the balancing controller 6 calculates a second matrix H of degrees of freedom linkage, the matrix n having the following values: — value 1 in its line tdryl, column tx, — value j at its line tdryl, column ty, — value j at its line tdrxl, column tx, — value -1 in its line tdrxl, column ty, — value -1 in its line tdry2, column tx, — value -j at its line tdry2, column ty, — value -j at its line tdrx2, column tx, — value 1 in its line tdrx2, column ty, — 0 elsewhere, where j is the complex number square root of -1. Matrix II is a sparse matrix (due to the presence of 0s).

[0105] X is a first direction perpendicular to the axis 30 of rotation. Y is a second direction perpendicular to the first direction X and to the axis 30 of rotation. tx is the index of the degree of freedom of translational movement along the X direction of the node Ne, ty is the index of the degree of freedom of translational movement along the Y direction of the node Ne, tdrxl is the index of the degree of freedom of rotational movement around the X direction of the node Ng, tdryl is the index of the degree of freedom of rotational movement around the Y direction of the node Ng, tdrx2 is the index of the degree of freedom of rotational movement around the X direction of the node Nd, tdry2 is the index of the degree of freedom of rotational displacement around the Y direction of node Nd.

[0106] During step E0223, the balancing controller 6 calculates a third passage matrix R, having m rows and n columns, where i is the index for the rows of the matrix R, as well as respectively for the sensors c; of vibrations of the rotor 3 and goes from 1 to m, n is the number of degrees of freedom of the finite element model, f is the index for the columns of the matrix R, as well as for the degrees of freedom of movement corresponding to the vibration sensors c; of the rotor 3 for i ranging from 1 to m. Generally speaking, R is the matrix of the passage which makes the values ​​of the numerical model correspond to those measured by the vibration sensors.

[0107] The balancing controller 6 calculates the third passage matrix R having the following values: R(i, ti)= 1 for i ranging from 1 to m, 0 elsewhere. The matrix R is a sparse matrix (due to the presence of 0s).

[0108] During step E0224, the balancing controller 6 calculates the matrix 3, having m rows and n columns, where S — R - ( / - H • • A"1 • Il ) 'A'1 being the inverse matrix, having been calculated 6 balance controller, matrix A.

[0109] I is the identity matrix.

[0110] According to one embodiment of the invention, the stability map 100 is predetermined by the balancing controller 6 using the finite element model. The balancing controller 6 can calculate the stability map 100 in the following manner.

[0111] For each pair of values ​​H and [3, the balancing controller 6 calculates the eigenvalues ​​v of the fourth matrix rp mentioned below:

[0112]

[0113] where / is the identity matrix of the same size as A. The matrices A and n have already been defined above.

[0114] If the real values ​​of all the eigenvalues ​​v of the fourth matrix T are strictly negative, then the pair H, [3 is said to be stable and is in the stable zone 101.

[0115] Mathematically, the stability condition is written:

[0116] max{^(v) such asdet^W - v • I) =0} <0}

[0117] where det denotes the determinant, max denotes the maximum,.

[0118] If this condition is not met, then the couple H, [3 is said to be unstable and is in the unstable zone 102.

[0119] The invention also relates to the rotating machine 1 comprising the stator 2 provided with the vibration sensor(s) 4, the rotor 3 described above, the heat treatment head 7 described above, the angular position sensor(s) 5 described above and the balancing controller 6 configured to implement the steps described above.

[0120] The invention also relates to a computer program comprising code instructions for implementing at least the second and third steps E20, E30 of the method for balancing the rotor 3 of the rotating machine 1 as described above, when the computer program is executed on the balancing controller 6 described above.

[0121] In a sixth embodiment, not shown, the vibration reduction factor Fr can be determined in a manner other than the fifth embodiment. For example, the balancing controller 6 can calculate the vibration reduction factor Fr of the prescribed stability card 100 by measuring by the sensor 5 the first amplitude Qeq of the vibrations V obtained for each heating power P mentioned above (i.e. for each pair of H and [3 set by the balancing controller 6 on the heat treatment head 7) during the rotation of the rotor 3, and by dividing this first amplitude Qeq by the second amplitude Qo of the vibrations V measured by the sensor 5 in the absence of this heating power P during the rotation of the rotor 3, i.e. F,= Qeq / Q0.

[0122] The third embodiment can be combined with the first embodiment or with the second embodiment.

[0123] The fourth embodiment can be combined with the first embodiment or with the second embodiment or with the third embodiment.

[0124] The fifth embodiment can be combined with the first embodiment or with the second embodiment or with the third embodiment or with the fourth embodiment.

[0125] The sixth embodiment can be combined with the first embodiment or with the second embodiment or with the third embodiment or with the fourth embodiment.

[0126] Other embodiments that can be combined with each of the embodiments and examples described above are described below.

[0127] According to an embodiment of the invention, shown in [Fig. 3], the heat treatment head 7 is configured to apply the heating power to a portion PT of the circumference 31 of the rotor 3, located opposite the determined angular range 0 during the rotation of the rotor 2 around the axis 30, as shown by way of example in [Fig. 2]. The determined angular range 0 may be relatively narrow. According to an embodiment, the determined angular range 0 may be less than or equal to 180° or 90°, in particular less than or equal to 45°, or less than or equal to 20°, or less than or equal to 5°, or less than or equal to 1°. The determined angular range 0 is greater than 0°, in particular greater than or equal to 0.1° or 0.5°.

[0128] According to an embodiment of the invention, shown in [Fig.2], the heat treatment head 7 occupies a determined length L (non-zero) parallel to the axis 30 of rotation opposite the rotor 3 and is capable of applying the heating power to the rotor 3 in the determined length L without contact with the rotor 3. The determined length L is greater than zero and for example greater than 5 mm.

[0129] According to an embodiment of the invention, shown in [Fig. 4], the balancing controller 6 of the rotor 3 is configured to adjust at least one instant Ti of activation of the contactless heating power of the heat treatment head 7 and / or at least one duration D of activation of the contactless heating power of the heat treatment head 7 from the activation instant Ti and / or an amplitude Pc of the heating power of the heat treatment head 7 as a function at least of the instantaneous angular position ô having been measured by the angular position sensor 5 of the rotor 3. The balancing controller 6 of the rotor 3 can control by a pulse signal controlling the heat treatment head 7. The amplitude Pc of the heating power can be in pulse form as a function of time t, as illustrated as an example in [Fig.4].

[0130] According to one embodiment, the balancing controller 6 makes it possible to adjust the duration D of activation of the heating power to the rotor 3 during each period T of rotation of the rotor 3 around the axis 30. The head 7 controlled by the controller therefore applies, in the determined angular range 0 and during the activation duration D, the heating power to the circumference 31 of the rotor 3. The controller 7 therefore controls the heat treatment head 7 to apply the heating power to a localized zone PT of the circumference 31 of the rotor 3. The controller 6, from the analysis of the vibrations recorded by the vibration sensor(s) 4, calculates the heating power, its duration D, as well as the angular sector ANG of the rotor 3 where the heating power is to be applied.

[0131] For example, as illustrated in [Fig.4], the duration D of activation of the non-zero amplitude Pc of the contactless heating power of the heat treatment head 7 from the activation time Ti is less than the period T of rotation of the rotor 3 to complete a 360° turn around the rotation axis 30 relative to the stator 2. [Fig.4] shows the amplitude AMP of the heat treatment sent by the head 7 on the ordinate as a function of the time t on the abscissa. Thus, in the example of [Fig.4], the duration D of activation of the contactless heating power of the heat treatment head 7 at the non-zero amplitude Pc from the activation time Ti is followed or preceded during the rotation period T by a duration I of inactivation of the head 7 so as not to apply heating power to the rotor 3 at zero amplitude or by a duration I of application of a second heating power AT2 having an amplitude lower than the amplitude Pc of duration D.The balancing controller 6 can be configured to perform pulse width modulation of the heating power.

[0132] According to an embodiment of the invention, the heat treatment head 7 therefore makes it possible to heat treat an angular sector ANG, determined and less than 360°, of the circumference 31 of the rotor 3 in rotation around the axis 30, having the duration D less than the period T of rotation of the rotor 3, the period T of rotation being the time taken by the rotor 3 to complete a 360° turn around the axis 30 of rotation. For example, the instant Ti of activation of the contactless heating power of the heat treatment head 7 is periodic with the same period as the period T of rotation and / or the duration D of activation of the contactless heating power of the heat treatment head 7 from the instant Ti of activation is periodic with the same period as the period T of rotation.This angular sector ANG of the rotor 3 corresponds in these cases to the duration D of activation of the contactless heating power of the heat treatment head 7 from the instant Ti of activation, extends . on ANG = 360°.D / T, starting at the angular position of the rotor 360°.Ti / T which corresponds to the instant u.T+Ti after the start uT of each period T of rotation, where u is a natural integer. This makes it possible to always process the same angular sector ANG of the circumference 31 of the rotor 2 by the head 7 during the successive rotations of the rotor 3 around the axis 30. Of course, in other embodiments, the instant Ti and the duration D could not be periodic.

[0133] According to one embodiment of the invention, the heat treatment head 7 is a contactless heating head 7. In this case, the head 7 increases the temperature of the circumference 31 of the rotor 3 in the determined angular range 0, and the heating power (then called hot spot) in the part PT of the circumference 31 of the rotor 3 (angular sector ANG) is positive and not zero. The heat treatment head 7 therefore sends heat in the determined angular range 0 and in the part PT (angular sector ANG) of the circumference 31 of the rotor 3. In the example illustrated in [Fig.2], the part PT located opposite the contactless heating head 7 is heated by this contactless heating head 7 and is the hottest PT zone of the circumference 31 of the rotor 3.The fibers of the material constituting the rotor 3 in the zones ZI located near this part PT heated by the heating head 7 will expand more than the zones Z2 far from the part PT heated by the heating head 7 on the rotor 3. The material of the rotor 3 in the zones ZI will therefore tend to move more than the material of the rotor 3 in the zones Z2 by moving away from the heating point PT located opposite the heating head 7, thus creating a tension of the parts ZI close to the heating zone PT. This tensioning is not uniform along the circumference 31 of the rotor 3 and will therefore cause a bending of the rotor 3 as illustrated in [Fig.5]. The bending thus created will generate a new distribution of the mass around the axis 30 of the rotor 3.By controlling the amplitude Pc and the angular position ANG of the heated portion PT, it is possible to modify the distribution of the mass around the axis 30 of rotation and thus to generate dynamic forces making it possible to oppose the forces generated by the defects of the rotor 3. The heating of the rotor 3 is carried out without any contact and in a non-intrusive manner. If the system is used to correct a mass imbalance of the rotor 3, then the correction is carried out without ever having to stop the rotation of the rotor 3, and without having to modify the rotation of the rotor. The correction can adapt to the speed of rotation of the rotor 3 around the axis 30 and to the appearance of new imbalances which would be created by other phenomena, for example cavitation erosion, the Newkirk effect or the Morton effect.

[0134] Different embodiments of this contactless heating head 7 are given below, with reference to figures 3, 6, 7, 8 and 9.

[0135] According to an embodiment of the invention, illustrated in [Fig. 3], the heat treatment head 7 is a head 7 for emitting a heating magnetic induction in the determined angular range 0 towards the rotor 3 and without contact with the rotor 3. The heat treatment head 7 comprises one (or more) coils 71 or inductances 71. The coil 71 or inductance 71 is configured to generate a magnetic field B, for example radial relative to the axis 30 of rotation, in the determined angular range 0, when the coil 71 or inductance 71 is crossed by an electric current sent by an electric current source of the controller 6 to the two ends 73 and 74 of the coil 71 or inductance 71. This magnetic field B makes it possible to heat the part PT of the circumference 31 of the rotor 3 rotating around the axis 30. The coil 71 or inductance 71 comprises for example one or more turns 72 between the two ends 73 and 74. The axis around which the coil 71 or inductance 71 or turn 72 is wound is normal or has a component normal to the surface 31 of the rotor 3.

[0136] According to an embodiment of the invention, illustrated in [Fig.6], the heat treatment head 7 is a head 7 for emitting RC radiation heating in the determined angular range 0 towards the rotor 3 and without contact with the rotor 3. The RC radiation touches the part PT of the circumference 31 of the rotor 3 rotating around the axis 30. The head 7 for emitting the RC radiation is without contact with the rotor 3.

[0137] According to another embodiment of the invention, illustrated in [Fig.7], the heat treatment head 7 is a head 7 for emitting a laser beam FL heating in the determined angular range 0 towards the rotor 3. The laser beam FL touches the part PT of the circumference 31 of the rotor 3 rotating around the axis 30. The head 7 for emitting the laser beam FL is without contact with the rotor 3.

[0138] According to one embodiment of the invention, the machine 1 comprises a single heat treatment head 7, a single rotor vibration sensor 4 and a single rotor angular position sensor 5 3.

[0139] According to another embodiment of the invention, the machine 1 comprises several heat treatment heads 7, which are mounted on the stator 2.

[0140] According to an embodiment of the invention, illustrated in [Fig.9], on the stator 2 is mounted a displacement device 22 for moving the heat treatment head 7 along the axis 30 of rotation and / or around the axis 30 of rotation. The displacement device 22 makes it possible to move along the axis 30 of rotation the part PT of the circumference 31 of the rotor 3 (angular sector ANG), to which the heat treatment head 7 applies the heating power without contact, for example to bring this part PT closer to a cantilevered mass of the rotor 3.

Claims

Claims

1. Method for balancing the rotor of a rotating machine (1), the rotating machine (1) comprising a stator (2), the rotor (3) being able to rotate about an axis (30) of rotation relative to the stator (2), the rotating machine (1) comprising at least one vibration sensor (4) of the rotor (3), the vibration sensor (4) being mounted on the stator (2), at least one heat treatment head (7), which occupies a determined angular range (0) of less than 360° about the axis (30) of rotation opposite the rotor (3), which is without contact with the rotor (3) and which is able to apply to the rotor (3) without contact with the rotor (3) in the determined angular range (0), a heating power, being mounted on the stator (2), at least one sensor of angular position in rotation of the rotor (3) about the axis (30) of rotation relative to the stator (2) being mounted on the stator (2), the machine comprising a controller (6) for balancing the rotor (3),characterized in that the rotor (3) balancing controller (6) is capable of adjusting the heating power P = r- H • V, where H is a parameter for adjusting an amplitude of a bending moment of the rotor (3), created by the heat treatment head (7), and is a real greater than or equal to zero, [3 is a parameter for adjusting a phase of the heating power, r is a coefficient of sensitivity of bending of the rotor (3) to the heating power applied by the heat treatment head (7), the sensitivity coefficient r being pre-recorded in the balancing controller (6), at least one prescribed stability map (100) of the rotor (3) for at least one determined rotational speed of the rotor (3) around the axis (30) of rotation relative to the stator (2) and for at least one axial position of the heat treatment head (7), being pre-recorded in the balancing controller (6) and indicating at least one stable zone (101) and at least one unstable zone (102) for pairs of values of H and [3,the stability map (100) being parameterized by a vibration reduction factor Fr determined at least in the stable zone (101), the method comprising at least the following steps (E10, E20, E30), carried out in an iterative manner during the rotation of the rotor (3) around, of the rotation axis (30) relative to the stator (2) at the determined rotation speed, for, at each iteration k: during a first step (E10), measuring, by the vibration sensor (4), an amplitude Vk of a vibration V of the rotor (3) and a phase ak of the vibration V of the rotor (3) relative to a phase reference according to the equation V — Vk • during a second step (E20), identifying a value Hk of the adjustment parameter H and a value [3k of the adjustment parameter [3, which are located in the stable zone of the prescribed stability map (100) and for which Fr < 1, by the balancing controller (6), during a third step (E30), applying the heating power p _ ra , y ak+Pk) Pæ" 'a heat treatment head (7) via the balancing controller (6) to the rotor (3) and in the presence of the measured vibration V by the vibration sensor (4).

2. Method according to claim 1, characterized in that the coefficient r of bending sensitivity of the rotor (3) to the heating power applied by the heat treatment head (7) is prescribed in the balancing controller (6) as being equal to the ratio (r _ pi ) of a determined and non-zero actual value Pb of the heating power to a measured or calculated value (MJ of bending moment of the rotor (3), caused by the application of the actual value (PO of the heating power by the heat treatment head (7) via the balancing controller (6) to the rotor (3).

3. Method according to any one of the preceding claims, characterized in that r ■ H ■ Vk< Pmax where Pmax is a maximum, positive and non-zero real value of the heating power.

4. Method according to any one of claims 1 to 3, characterized in that the rotor (3) is guided in rotation about its axis (30) of rotation relative to the stator (2) by at least two bearings (20a, 20b) spaced from each other along the axis (30) of rotation, the heat treatment head (7) and the vibration sensor (4) being placed between the bearings (20a, 20b), [3k = 0° for the machine (1) whose rotor (3) has a mass (Mb M2) cantilevered from one of the bearings (20a, 20b), which is less than an intermediate mass (Mo) of the rotor (3) located between the bearings (20a, 20b) and for the machine (1) operating at a rotation frequency of the rotor (3), which is greater than a frequency of a first bending mode of the rotor (3).

5. Method according to any one of claims 1 to 3, characterized in that the rotor (3) is guided in rotation about its axis (30) of rotation relative to the stator (2) by at least two bearings (20a, 20b) spaced from each other along the axis (30) of rotation, the heat treatment head (7) and the vibration sensor (4) being placed between the bearings (20a, 20b), [3k = 180° for the machine (1) whose rotor (3) has a mass (Mb M2) cantilevered from one of the bearings (20a, 20b), which is less than an intermediate mass (Mo) of the rotor (3) located between the bearings (20a, 20b) and for the machine (1) operating at a rotational frequency of the rotor (3), which is less than a frequency of a first bending mode of the rotor (3).

6. Method according to any one of claims 1 to 5, characterized in that the first, second and third steps (E10, E20, E30) are carried out in an iterative manner for at least one previous iteration k and at least one following iteration k+1, for, during the second step (E20) of the following iteration k+1: adjusting by the balancing controller (6) the value Hk+[ of the adjustment parameter H such that, WHERE Vk+i is the amplitude of the vibration V of the rotor (3), having been measured during the first step (E10) of the following iteration k+1, y is an iteration adjustment factor, which is a strictly positive real number and less than or equal to 1 and which is pre-recorded in the balancing controller (6),and identifying by the balancing controller (6) the value P of the adjustment parameter [3 from the prescribed stability map (100) making it possible to obtain the smallest value of the vibration reduction factor Fr among a finite set (EFr) of determined values of the vibration reduction factor Fr.,

7.

8. 7. Method according to claim 6, characterized in that y = L Method according to any one of claims 1 to 5, characterized in that the first, second and third steps (E10, E20, E30) are carried out in an iterative manner for at least one previous iteration k and at least one subsequent iteration k+1 until the value Hk+i of the adjustment parameter H of the subsequent iteration k+1 reaches a prescribed threshold Hmax, for: during the second step (E20) of the subsequent iteration k+1, setting by the balancing controller (6) the value Hk+i of the adjustment parameter H and the value [3k+i of the adjustment parameter [3, with Hk+i equal to a prescribed function (f), increasing as a function of time up to the prescribed threshold Hmax applying during the third step (E30) of the subsequent iteration k+1, by the heat treatment head (7) via the balancing controller (6) to the rotor (3) and in the presence of the vibration V measured by the vibration sensor (4), the heating power p -r.j4 .y . where Vk+i is the amplitude of the vibration V of the rotor (3), having been measured during the first step (E10) of the following iteration k+1.

9. Method according to claim 8, characterized in that the prescribed increasing function (f) is a linear ramp increasing as a function of time up to the prescribed threshold Hmax or an affine ramp increasing as a function of time up to the prescribed threshold Hmax.

10. Method according to any one of the preceding claims, characterized in that the method further comprises the following steps (E1, E2, E3), carried out by the balancing controller (6) before the first, second and third steps (E10, E20, E30): identification (E1) of a pair of a target value Hc of the adjustment parameter H and a target value [3C of the adjustment parameter [3, which is located in the stable zone (101) of the prescribed stability map (100) and giving the smallest value of the vibration reduction factor Fr, strictly less than 1, among a finite set (EFr) of determined values of the vibration reduction factor Fr, identification (E2) of a pair of a starting value Hd of the adjustment parameter H and a starting value [3d of the adjustment parameter [3,which is located in the stable zone (101) of the prescribed stability map (100) and for which the vibration reduction factor Fr is strictly less than 1, the starting value Hd of the adjustment parameter H being less than the target value Hc of the adjustment parameter H, identification (E3) in the prescribed stability map (100) of a path (103) going from the couple of Hd and [3d to the couple of Hc and [3C by the, successive pairs of values of Hk and [3k, which are located in the stable zone (101) of the prescribed stability map (100), the first, second and third steps (E10, E20, E30) being carried out in an iterative manner for the successive pairs of values of Hk and [3k to go from the pair of Hd and [3d to the pair of Hc and [3

11. c* Method according to claim 10, characterized in that the method further comprises, before the first, second and third steps (E10, E20, E30), a step (E4) of choosing a total, non-zero duration, tm to go from the pair of Hd and [3d to the pair of Hc and [3C, carried out by the balancing controller (6).

12. Method according to any one of the preceding claims, characterized in that the first, second and third steps (E10, E20, E30) are carried out in an iterative manner for at least one previous iteration k and at least one following iteration k+1, for: if k=0 or Vk+i > Vk, identifying by the balancing controller (6) during the second step (E20) of the following iteration k+1 the value Hk+[ of the adjustment parameter H and the value j of the adjustment parameter [3, which are located in the stable zone (101) of the prescribed stability map (100), and otherwise identifying by the balancing controller (6) during the second step (E20) of the following iteration k+1 the value Hk+[ of the adjustment parameter H and the value of the adjustment parameter [3 with Hk+i= Hk and [3 k+l= [3k-

13. Method according to any one of the preceding claims, characterized in that the machine comprises m sensors c; of vibrations of the rotor (3), which are mounted on the stator (2), where m is a natural integer greater than or equal to 2 and i is an integer ranging from 1 to m, the method further comprises the following steps, before the first, second and third steps (E10, E20, E30): - during a first preparatory step (E01), measurement of the complex vibration measurement vector [ . T by the m sensors Q , = \ q, ' dt ldi C; of vibrations (4), where is the amplitude of the vibrations of the rotor (3) measured respectively by the sensor c; of vibrations (4) and is the phase of the vibrations of the rotor (3) measured respectively by the sensor C; of vibrations (4), in a second preparatory step (E02), calculating the prescribed stability map (100) in association with values of the vibration reduction factor Fr by repeating the following sub-steps for each value of H and fi lying in the stable zone (101) of the stability map (10) by the balancing controller (6): - calculate (E021) Qj solution of the system of equations: O nvpc { 1 T - calculate (E022) the values Fr (H, |3) of the vibration reduction factor Fr such that where the matrix E is calculated from the as follows: — calculate (E0221) a first matrix A such that A = -M-^2 + j-£lC + K the machine (1) being represented by a finite element model, comprising finite element models, in which the heat treatment head (7) is located between a node Ng of a mesh of the machine (1) and a node Nd of the mesh of the machine (1) and the vibration sensor (4) is located opposite a node Ne of the mesh of the machine (1), where M is a prescribed mass matrix of the finite element model of the machine (1), C being a prescribed damping matrix of the finite element model of the machine (1), K being a prescribed stiffness matrix of the finite element model of the machine (1), £2 is the rotation speed, — calculate (E0222) a second matrix II of degrees of freedom link, matrix II having the following values: — value 1 in its line tdryl, column tx, — value j at its line tdryl, column ty, — value j at its line tdrxl, column tx, — value -1 in its line tdrxl, column ty, — value -1 in its line tdry2, column tx, — value -j at its line tdry2, column ty, — value -j at its line tdrx2, column tx, — value 1 in its line tdrx2, column ty, — 0 elsewhere, where j is the complex number square root of -1, X is a first direction perpendicular to the axis (30) of rotation, Y is a second direction perpendicular to the first direction X and to the axis (30) of rotation, tx is the index of the degree of freedom of translational displacement along the X direction of the node Ne, ty is the index of the degree of freedom of translational displacement along the Y direction of the node Ne, tdrxl is the index of the degree of freedom of rotational displacement around the X direction of the node Ng, tdryl is the index of the degree of freedom of rotational displacement around the Y direction of the node Ng, tdrx2 is the index of the degree of freedom of rotational displacement around the X direction of the node Nd, tdry2 is the index of the degree of freedom of rotational displacement around the Y direction of the node Nd, — calculate (E0223) a third passage matrix R, having m rows and n columns, where i is the index for the rows of the matrix R, as well as for the rotor vibration sensors c; respectively (3) and ranges from 1 to m, n is the number of degrees of freedom of the finite element model, f is the index for the columns of the matrix R, as well as for the degrees of freedom of movement corresponding to the rotor vibration sensors Ci respectively (3) for i ranging from 1 to m, the passage matrix R having the following values: R(i, t;)= 1 for i going from 1 to m, 0 elsewhere, — calculate (E0224) the matrix S , having m rows and n columns, where S — R - (j - H - ■ A"1 • U ) °where A'1 is the inverse matrix, having been calculated, from the matrix A.

14. Rotating machine (1) comprising a stator (2), a rotor (3) capable of rotating around an axis (30) of rotation relative to the stator (2), at least one vibration sensor (4) of the rotor (3), the vibration sensor (4) being mounted on the stator (2), at least one heat treatment head (7), which occupies a determined angular range (0) of less than 360° around the axis (30) of rotation opposite the rotor (3), which is without contact with the rotor (3) and which is capable of applying to the rotor (3) without contact with the rotor (3) in the determined angular range (0) a heating power, being mounted on the stator (2), at least one sensor (5) of angular position in rotation of the rotor (3) around the axis (30) of rotation relative to the stator (2) being mounted on the stator (2), a rotor (3) balancing controller (6), characterized in that the rotor (3) balancing controller (6) is capable of adjusting the heating power P = r- H • V where H is a parameter for adjusting a bending moment amplitude created by the heat treatment head (7) and is a real number greater than or equal to zero, [3 is a parameter for adjusting a phase of the heating power, r is a coefficient of sensitivity of the rotor (3) to the heating power applied by the heat treatment head (7), the sensitivity coefficient r being pre-recorded in the balancing controller (6), at least one prescribed stability map (100) of the rotor (3) for at least one determined rotational speed of the rotor (3) around the axis (30) of rotation relative to the stator (2) and for at least one axial position of the heat treatment head (7), being pre-recorded in the balancing controller (6) and indicating at least one stable zone (101) and at least one unstable zone (102) for pairs of values of H and [3, the stability map (100) being parameterized by a vibration reduction factor Fr determined at least in the stable zone (101),the rotor (3) balancing controller (6) and the vibration sensor (4) being configured to implement at least the following steps (E10, E20, E30), carried out in an iterative manner during the rotation of the rotor (3) around the rotation axis (30) relative to the stator (2) at the determined rotation speed, for, at each iteration k:, during a first step (E10), measurement, by the vibration sensor (4), of an amplitude Vk of a vibration V of the rotor (3) and of a phase ak of the vibration V of the rotor (3) relative to a phase reference according to the equation V — • eP\ during a second step (E20), identification of a value Hk of the adjustment parameter H and a value [3k of the adjustment parameter [3, which are located in the stable zone of the prescribed stability map (100) and for which F r < 1, by the balancing controller (6), during a third step (E30), application of the heating power p _ r H y ^ / (by the heat treatment head (7) via the balancing controller (6) to the rotor (3) and in the presence of the vibration V measured by the vibration sensor (4).

15. Computer program, comprising code instructions for implementing at least the second and third steps (E20, E30) of the method for balancing the rotor (3) of a rotating machine (1) according to any one of claims 1 to 13, when the computer program is executed on a controller (6).

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