CONTROL OF AN ELECTRIC LATHE

Description

Technical field

[0001] The present invention relates to the field of control of rotating electrical machines. Etat de la technique antérieure

[0002] An electric machine can be used in all industrial sectors. For example, certain electric machines with high torque, low inertia and fast response times are advantageously used in the motorization of actuators, particularly in aircraft embedded systems.

[0003] Generally speaking, an electrical machine, for example an electric motor, is equipped with a control or piloting device designed to regulate the voltage at its terminals according to the electrical feedback data and, above all, a precise measurement of the angular position. i of the rotor. This information usually comes from a resolver or position sensor, often mounted on the shaft of the electric machine, to measure the mechanical angle. I'm a mechanic. (in rad) of the rotor, also called mechanical position.

[0004] The mechanical position measured by the resolver is a crucial input for controlling the electrical machine. Indeed, the electrical position I am here. which results from this is used to perform frame transformations (for example, Park transforms and inverse Park transforms) associated with the control of the electric machine.

[0005] Furthermore, this information about the mechanical position is used to estimate the mechanical rotational speed and to perform coordinate system changes in the control system. Typically, a derivative is used to estimate the mechanical speed from the measured mechanical position of the rotor. The electrical speed oh elec deduced from the mechanical speed can be used at the machine control level to ensure decoupling between the d and q axes in a rotating synchronous frame (d,q).

[0006] However, the position signal generated by the resolver is not clean in the sense that it contains harmonics which may be of vibrational origin on the shaft of the electrical machine and which may possibly be superimposed on signals from a Resolver-to-Digital Converter (RDC).

[0007] Furthermore, the classical calculation of mechanical velocity is based on calculating a derivative of mechanical position i contains the same harmonics. Any frequency harmonic that overlaps with these two quantities, position and velocity, could generate torque vibrations on the shaft and additional iron and copper losses in the electrical machine.

[0008] One solution found in the state of the art involves using digital low-pass filters to attenuate the harmonic content of the two signals, velocity and position. However, the velocity information may be attenuated because the harmonics in question are very often low-frequency. Indeed, to be effective, the cutoff frequency chosen for the low-pass filter must be close to the DC signal, which has zero frequency. Furthermore, the angle information may be delayed due to the phase shift introduced by the digital low-pass filter. These two consequences can compromise the stability and feasibility of the electrical machine control.

[0009] Documents US2018 / 052009, WO2021 / 121770, and FR3104856 describe examples of control devices for rotating electrical machines, according to the prior art. The object of the present invention is therefore to propose a method and a system for determining control parameters (position and speed), overcoming the aforementioned drawbacks, allowing for high accuracy in determining an electrical position free of harmonics and without phase shift relative to the mechanical position, thus enabling the control of an electrical machine with high stability and reliability. Presentation of the invention

[0010] The invention is defined in independent claims 1 and 10. The present invention relates to a method for determining control parameters of a rotating electrical machine, comprising the following steps: mechanical position measurement I'm a mechanic.from the axis of a rotor of the rotating machine, construction of two fictitious two-phase signals x a , x b Based on the measurement of said mechanical position, an open-loop determination of an estimate of the electrical velocity, called the estimated open-loop electrical velocity, is performed. oh estflt , using said fictitious two-phase signals, injection of said two fictitious two-phase signals x α , x β and of said estimated open-loop electrical speed oh estflt in a phase-locked loop, and generation by said phase-locked loop, of the effective electrical position i of the rotating machine.

[0011] This process allows for the determination with high precision of the electrical angular position free of harmonics and without phase shift relative to the measured position of the rotor axis of the rotating machine.

[0012] The measurement of mechanical position I'm a mechanic.can be achieved by a position sensor mounted on the shaft of the electric machine.

[0013] Advantageously, the construction of said two fictitious two-phase signals involves the following steps: calculate an estimate of an electrical position, called the estimated electrical position the elec, by multiplying the mechanical position I'm a mechanic. by the number p of pole pairs of the electrical machine, and calculate from said estimated electrical position the elec, two normalized sinusoidal signals, offset from each other by 90°, thus forming the said two fictitious two-phase signals.

[0014] Advantageously, the determination of the estimated electric speed oh estflt It involves the following steps: generation of two pulsed signals at the zero crossings of said fictitious two-phase signals x a ,x b ,determination of a preliminary estimate of an electrical speed, called preliminary electrical speed oh, from the sum of said two pulsating signals and a maximum useful electrical frequency associated with a maximum rotational speed, and determination of the estimated open-loop electrical speed oh estflt by applying a selective bandpass filter to said preliminary electrical velocity oh, that's it.

[0015] Advantageously, the determination of these two pulse signals involves the following steps: transform the two fictitious sinusoidal two-phase signals into square signals of predetermined width, and generate said two pulsating signals by detecting the changes in rising and falling edges of said square signals.

[0016] Advantageously, the generation by said phase-locked loop of the effective electrical position iThe rotating machine process involves the following steps: apply a rotation matrix to the fictitious two-phase signals x α , x β to extract a continuous component xd of the fictitious signal along the d-axis of a rotating synchronous frame, control the DC component xd to an instruction x d * zero, determine a compensator y based on the difference between said setpoint and said DC component, determine an estimate of a phase-locked electrical speed oh PLL, by adding said corrector y to the estimated electrical speed oh estflt in open loop, determine an estimate of a preliminary angular position ϑ v by integrating said phase-locked electrical speed oh PLL, and determine the effective electrical position of the electric machine by compensating for a delay in the preliminary angular position estimation ϑ v of the shaft of the electric machine.

[0017] Advantageously, according to a first embodiment, the method involves determining an effective electrical speed ω of the electrical machine by applying active low-pass filtering to the phase-locked electrical speed oh PLL.

[0018] Advantageously, according to a second embodiment, the process involves determining an effective electrical speed oh of the electrical machine by applying a selective bandpass active filter to the DC component xd of the fictitious signal along the axis d of the rotating synchronous frame, the effective electrical speed oh corresponding then to the phase-locked electrical speed oh PLL .

[0019] Advantageously, according to a third embodiment, the process involves determining an effective electrical speed ohof the electric machine by applying a velocity observer to the effective electrical position of the electric machine, the effective electrical velocity oh corresponding then to a filtered image of the electrical velocity obtained by said velocity observer.

[0020] The invention also relates to a method for controlling a rotating machine comprising determining control parameters according to the previous aspect.

[0021] The invention also relates to a system for determining control parameters of a rotating electrical machine, comprising: a dummy two-phase reference frame module configured to construct two dummy two-phase signals ( x a ,x b ) based on a measurement of the mechanical position I'm a mechanic.From the axis of a rotating machine rotor, received from a position sensor, an open-loop module configured to determine, in open loop, an estimate of the electrical speed, called the estimated open-loop electrical speed oh estflt , using said fictitious two-phase signals, a phase-locked loop module configured to generate the effective electrical position i of the rotating machine from said two fictitious two-phase signals ( x α , x β ) and using said estimated open-loop electrical velocity oh my god received from the open loop module.

[0022] The invention also relates to a control device for a rotating electrical machine comprising a system for determining electrical parameters according to the above characteristics.

[0023] The invention also relates to a rotating electrical machine comprising the control device according to the above characteristics. Brève description des figures

[0024] Other features and advantages of the invention will become apparent upon reading preferred embodiments of the invention shown with reference to the accompanying figures, among which: [ Fig. 1 ] schematically represents a rotating electrical machine comprising a system for determining control parameters of the electrical machine, according to an embodiment of the invention; [ Fig. 2 ] schematically represents a system for determining control parameters, according to a preferred embodiment of the invention [ Fig. 3A ] ] Fig. 3B ] ] Fig. 3C ] are curves showing the result on the position of the electrical machine, according to the method of the invention; [ Fig. 4] is a zoom comparing the electrical speed obtained according to the state of the art with that obtained according to the process of the invention; and [ Fig. 5 ] And [ Fig. 6 ] schematically represent control parameter determination systems, according to second and third preferred embodiments of the invention. Description of the modes of realization

[0025] The concept of the invention is to perform digital processing on the measurement signal of the mechanical position of the rotor shaft of an electric machine by creating a fictitious two-phase reference frame and using this two-phase reference frame as input data for a phase-locked loop to generate a resulting position free of harmonics. Furthermore, this phase-locked loop is also used to calculate the speed.

[0026] There Fig. 1schematically represents a rotating electrical machine comprising a system for determining control parameters of the electrical machine, according to an embodiment of the invention.

[0027] The rotating electrical machine 1 (in motor or generator mode) typically comprises stator windings 3 and a rotor 5 with p pairs of poles (of which only one pair is represented, i.e. p = 1).

[0028] A resolver or position sensor 9 (for example, a Hall effect sensor) is mounted on the shaft of the electrical machine 1 to measure the mechanical position θ m of the rotor shaft 5.

[0029] According to the invention, the electrical machine 1 is equipped with a control parameter determination system 11. This system 11 receives the mechanical position signal. θ mmeasured by position sensor 9 to filter out low frequency harmonics that may be present in this signal without introducing phase shift.

[0030] The control parameter determination system 11 thus transmits useful positioning signals to a control device 13 i of the rotor and possibly on the rotational speed devoid of harmonics.

[0031] The control device 13 uses the specific signals received from the control parameter determination system 11, as well as the usual electrical feedback data, to control or drive the operating point of the electrical machine 1 according to the actual position i of rotor 5.

[0032] The control parameter determination system 11 includes an electronic circuit 15 configured to perform digital filtering processing on the mechanical position signal θ mmeasured by position sensor 9. The resulting angular position is then free of harmonics. The electronic circuit 15 is also configured to calculate the resulting mechanical speed without propagating harmonics and without attenuating the signal.

[0033] According to one embodiment of the invention, the electronic circuit 15 comprises a two-phase dummy reference module 17, an open-loop module 19, and a phase-locking loop module 21.

[0034] The dummy two-phase reference module 17 is configured to construct two dummy two-phase signals ( x a ,x b ) based on the measurement of the mechanical position θ m .

[0035] The open-loop module 19 is configured to determine an estimate of the electrical speed, called the estimated open-loop electrical speed oh estflt , using fictitious two-phase signals ( x a , x b ).

[0036] The two fictitious two-phase signals ( x α , x β ) and the estimated open-loop electrical speed oh estflt are injected into the phase-locked loop module 21. The latter 21 exploits the fictitious two-phase signals ( x α , x β ) as input data to determine the electrical position of the electric machine while using the estimated open-loop electrical speed oh estflt to improve the dynamics of the position control system. This allows the phase-locked loop module 21 to generate an effective electrical position i very precise rotor 5 of electric machine 1 and free of harmonics.

[0037] It should be noted that modules 17, 19, and 21 can be hardware and / or software modules. Digital processing can then be performed by a microprocessor included in the electronic circuit 15. Furthermore, the electronic circuit 15 can be included in the control device 13.

[0038] There Fig. 2 schematically represents a system for determining control parameters, according to a preferred embodiment of the invention.

[0039] As on the Fig. 1 , the control parameter determination system 11 comprises an electronic circuit 15 including a two-phase dummy reference module 17, an open loop module 19, and a phase-locking loop module 21.

[0040] The two-phase dummy reference frame module 17 comprises a multiplier element 171 and an orthonormalization element 172. The multiplier element 171 multiplies the mechanical position signal I'm a mechanic.derived from position sensor 9 by the number p of pole pairs of the electrical machine 1. At the output of this multiplier element 171, an estimate of an electrical position is obtained, called the estimated electrical position. the elec in radians, of the angular position of the rotor: θ elec = p ⋅ θ meca

[0041] The orthonormalization element 172 then calculates, from the estimated electrical position the elec, two normalized sinusoidal signals, shifted from each other by 90°, thus forming two fictitious two-phase signals ( x α , x β ) : x α = sinθ é lec x β = cosθ é lec

[0042] The two fictitious two-phase signals ( x a , x b ) form a fictitious two-phase reference frame constituting input data for the open loop modules 19, and phase-locked loop 21.

[0043] The open loop module (symbolized "flt") 19 comprises three units: a pulse generation unit 191, an average value generation unit 192 and a selective filtering unit 193.

[0044] The pulse generation unit 191 is configured to generate two pulse signals at the zero crossings of the dummy two-phase signals ( x a ,x b ) . More specifically, this pulse generation unit 191 includes first 194 and second 195 detection elements and an addition element 196.

[0045] The first 194 and second 195 detection elements are configured to generate, at the zero crossings of their respective input signals x α And x α pulses whose duration is inversely proportional to a maximum useful electrical frequency f-max associated with a maximum rotation speed of the electric machine 1.

[0046] Each zero-crossing detection is coded so that the output of the first 194 and second 195 detection elements yields first and second pulsating signals. fronts xα , fronts xb respectively.

[0047] An example of coding is given below for the case of the first pulsed signal fronts xα knowing that the coding is similar for the second pulse signal fronts xβ .

[0048] Initially, the sinusoidal input signal x α is transformed into a square wave varying between 0 and 2, such that the maximum value 2 indicates a positive alternation of the sinusoidal signal x α and the minimum value 0 of the square wave signal indicates a negative alternation of x α , as follows: square = 2 , si x α > 0 square = 0 , si x α < 0 square = 1 , si x α = 0

[0049] Next, the rising and falling edges of the square wave signal are detected and interpreted by pulses of period Δt, equal to: Δ t = 1 2 ⋅ f max

[0050] More specifically, each of the first 194 and second 195 detection elements includes two rising and falling monostable circuits (not shown) so that the square signals are injected into these two monostable circuits.

[0051] For example, the rising monostable circuit is defined in relation to a sampling period You, in the following way: si y > − T e , alors fronts montants alpha = 1 sinon , fronts montants alpha = 0 Or y = k - T e and where the value k is defined according to the value of a binary variable u, in the following way: si u ≠ 0 , alors k = 1 2 ⋅ f max − ε si u = 0 , alors k = z − 1 ⋅ y

[0052] Furthermore, the following truth table (Table 1) allows us to deduce the value of the binary variable u: [Tab. 1] a = Z − 1 ⋅ fronts montants alpha ¯ b = 1 , si square alpha > Z − 1 ⋅ square alpha 0 , si square alpha ≤ Z − 1 ⋅ square alpha u = a ET b 0 0 0 0 1 0 1 0 0 1 1 1

[0053] Note that the logic of the descending monostable circuit is equivalent to that of the ascending monostable circuit. The only difference lies in the calculation of the binary parameter "b", which becomes as follows: b = 1 , si z − 1 ⋅ square alpha > square alpha 0 , si z − 1 ⋅ square alpha ≤ square alpha

[0054] The addition element 196 of the generation unit 191 is configured to add the two pulse signals fronts xα, fronts xβ. Thus, at the output of this addition element 196, we have a superposition signal ZC: ZC = fronts x α + fronts x β

[0055] Furthermore, the average value generation unit 192 is configured to determine a preliminary estimate of an electrical speed, called the preliminary electrical speed oh, that's it. This preliminary electrical speed oh yes is calculated from the ZC superposition signal and the maximum useful electrical frequency fmax. More specifically, the ZC superposition signal is multiplied by 2πf max and divided by 2, according to the following formula: ω est = ZC ⋅ 2 ⋅ π ⋅ f max 2

[0056] In addition, the selective filtering unit 193 of the open-loop module 19 is configured to apply a selective bandpass filter to the preliminary electrical velocity oh, that's it. At the output of this selective filter 193, and therefore at the output of the open-loop module 19, we obtain an estimate of the electrical speed, called the estimated open-loop electrical speed oh estflt .

[0057] Advantageously, this estimated open-loop electrical speed oh estflt is injected into the direct chain of the position control of the phase locking loop module 21, thereby improving the dynamics of this module 21.

[0058] The phase-locked loop module (symbolized as "PLL" for Phase-Locked Loop) 21 is a servo loop configured to converge the electrical position signal to a useful signal from an effective electrical position iof the electrical machine 1 devoid of harmonics. This effective electrical position i is a filtered image of the position measured by position sensor 9. The phase-locked loop module 21 is further configured to provide the effective electrical speed oh of the electrical machine also devoid of harmonics.

[0059] According to a first embodiment, the phase-locking loop module 21 comprises the following units (or sub-modules): a rotation unit 211, a control unit 212, a speed addition unit 213, an integration unit 214, a delay compensation unit 215, a position compensation unit 216, and an active filtering unit 217.

[0060] The rotation unit 211 is configured to apply a rotation matrix of an angle ϑ PLLcomp to fictitious two-phase signals x a ,x breceived from the dummy two-phase reference frame module 17. This allows the extraction of a DC component xd of the fictitious signal along the d-axis of a rotating synchronous frame of the Park frame type. Thus, the DC component xd The fictitious signal can be defined as follows: x d = x α ⋅ cosϑ PLL comp + x β ⋅ sinϑ PLL comp

[0061] The control unit 212 is a proportional-integral type controller applied to the error along the d-axis of the rotating synchronous frame. More specifically, the control unit 212 comprises a servo element 221 and a correction element 222.

[0062] The servo element 221 is configured to servo the DC component xd of the fictitious signal on the d-axis to a setpoint x d ∗ zero. The difference ε between the setpoint x d ∗ and the continuous component xd is then: x d ∗ − x d = ε

[0063] The correction element 222 is configured to determine a correction y based on the deviation between the setpoint x d ∗ and the continuous component xd This controller is of the proportional-integral type "PI" which is expressed according to a deactivated or activated state, as follows: y = K p PLL ⋅ x d ∗ − x d + T e ⋅ z z − 1 ⋅ K i PLL ⋅ x d ∗ − x d + y 0 with, Si Enable PLL = 0 , alors Reset = 1 et T e ⋅ z z − 1 ⋅ K i PLL ⋅ x d ∗ − x d + y 0 = y 0 : integrator disabled Si Enable PLL = 1 , alors Reset = 0 et T e ⋅ z z − 1 ⋅ K i PLL ⋅ x d ∗ − x d + y 0 = T e ⋅ z z − 1 ⋅ K i PLL ⋅ x d ∗ − x d + y 0 : integrator activated And, y 0 = 0 .

[0064] The gains { K pPLL , K iPLL} are calculated based on the phase-locked loop parameters according to the following two formulas: K p PLL = 2 ⋅ ξ PLL ⋅ ω n PLL x α ^ K i PLL = ω n PLL 2 x α ^

[0065] The values ​​of these phase-locked loop parameters are defined in Table 2 below: [Tab. 2] Parameter Expression / value Comment ξ PLL 0.707 Amortization factor of the PLL x α ^ 1 Valeur maxima des signals d'entrées f sPLL 15 [Hz] Example of PLL cutoff frequency value ω nPLL 2 · p · fs PLL [rad / s] Bande passante de la PLL sous forme de frequence angularaire

[0066] The y output of the correction element 222 is a correction (in rad / s) of the electrical speed which is used to obtain more precise information on the angular position of the shaft 5 of the electrical machine 1.

[0067] Electric speed ω is true The value estimated by the open-loop module 19 (based on zero-crossing detection) is injected into the forward loop via a predictive "FeedForward" action. This FeedForward action improves the dynamics of the PLL and allows the loop to converge towards the useful value of the shaft speed 5, especially when the PLL is activated at a non-zero shaft speed (for example, 15,000 rpm).

[0068] The addition unit 213 is an adder that is configured to add the y-corrector from the correction element 222 to the estimated electrical speed ω is trueinjected from the open-loop module 19. Thus, at the output of the addition unit 213, an estimate of a phase-locked electrical speed is obtained ω PLL: ω PLL = y + ω est flt

[0069] Next, the 214 integration unit is configured to integrate phase-locked electrical speed ω PLL , At the output of the integration unit 214, we then obtain an estimate of a preliminary angular position ϑ v referenced in relation to the signal x α , in the following way: ϑ v = T e ⋅ z z − 1 ⋅ ω PLL + ϑ v 0 with : si Enable PLL = 0 , alors Reset = 1 et ϑ v = ϑ v 0 : int é grateur d é sactiv é si Enable PLL = 1 , alors Reset = 0 et ϑ v = T e ⋅ z z − 1 ⋅ ω PLL + ϑ v 0 : int é grateur activ é And ϑ v 0 = 0 .

[0070] The 215 delay compensation unit is configured to compensate for a delay in the preliminary angular position estimation. ϑ vThis delay is compensated by taking into account the rotation of the electrical machine shaft at the scale of the sampling step used to generate the position used in the rotation matrix. Thus, at the output of the delay compensation unit 215, a compensated angular position is obtained. ϑ PLLcomp defined as follows: ϑ PLL comp = T e ⋅ z − 1 ⋅ ω PLL + z − 1 ⋅ ϑ v

[0071] The angular position compensation unit 216 of the shaft of the electric machine 1 is also configured to return the angle estimated by the phase-locked loop to the reference x α Indeed, the phase-locked loop is based on solving the following equation: x d ∗ − x d = 0

[0072] This is equivalent to solving the following trigonometric equation: x α ⋅ cos ϑ PLL comp + x β ⋅ sin ϑ PLL comp = 0

[0073] Solving this trigonometric equation leads to the following solution (modulo 2π): ϑ PLL = ϑ PLL comp + π 2

[0074] This solution gives the effective electrical position of the electrical machine 1.

[0075] Furthermore, the signals from this phase-locked loop are canceled when the loop is deactivated: ω = Enable PLL ⋅ ω PLL θ = Enable PLL ⋅ ϑ PLL , modulo 2 π with, Enable PLL = 0 , si la PLL est d é sactiv é e Enable PLL = 1 , si la PLL est activ é e

[0076] Advantageously, the phase-locked loop module 21 includes an active filter 217 configured to apply active low-pass filtering to the phase-locked electrical speed ω PLL To determine an effective electrical speed ω of the shaft of electrical machine 1. This filtering is carried out according to the equations below: ω PLL flt = T e ⋅ z z − 1 ⋅ y it, y = T e ⋅ z z − 1 − a ⋅ z − 1 ⋅ y − b ⋅ z − 1 ⋅ ω PLL flt + b ⋅ ω PLL With, ξ flt = 0.707, damping factor of the second-order filter ω nflt , filter cut-off angular frequency a = 2 ζω n flt b = ω n flt 2

[0077] THE Figs. 3A-3C are curves showing the result on the position of the electric machine, according to the method of the invention.

[0078] More specifically, the Fig. 3A illustrates the signal S1 from the position sensor 9 measuring the position of the electrical machine 1. This signal S1 shows the presence of low frequency harmonics.

[0079] There Fig. 3B illustrates the theoretical ideal signal S2 of the position of the electrical machine 1 devoid of harmonics.

[0080] There Fig. 3C Figure illustrates the signal S3 of the position of the electrical machine 1, as processed by the method or system according to the present invention. It is clearly visible that this signal S3 is harmonic-free and superimposed on the ideal signal S1 of the Fig. 3B This demonstrates the effectiveness of the system and method according to the invention in extracting useful information from a perturbed position measurement.

[0081] There Fig. 4 is a zoom comparing the electrical speed obtained according to the state of the art with that obtained according to the process of the invention.

[0082] The electrical speed in this figure relates to a turbine start-up profile over a wide range of speeds.

[0083] More specifically, curve C1 shows the electrical velocity signal obtained according to the prior art with a filtered derivative applied to the position measurement. Curve C2 shows the ideal theoretical electrical velocity signal if the measured position had been free of harmonics. Curve C3 shows the electrical velocity signal obtained according to the method of the present invention. The shape of curve C3 is identical to that of the ideal curve C2, demonstrating the effectiveness of the harmonic filtering. Furthermore, curve C3 is only slightly offset from C2, demonstrating the minimization of electrical velocity attenuation according to the present invention.

[0084] There Fig. 5schematically represents a system for determining control parameters, according to a second preferred embodiment of the invention.

[0085] This second embodiment differs from that of the Fig. 2 solely by the fact that it includes a selective bandpass active filter applied to the DC component xd (of the fictitious signal along the d-axis of the rotating synchronous frame) at the input of the phase-locked loop. In this case, the active low-pass filter 217 of the Fig. 2 is eliminated. Indeed, the effective electric speed ω According to this second embodiment, it corresponds to the phase-locked electrical speed ω PLL .

[0086] There Fig. 6 schematically represents a system for determining control parameters, according to a third preferred embodiment of the invention.

[0087] This third embodiment differs from that of the Fig. 2 solely by virtue of the fact that it includes a velocity observer 417 applied to the signal of the effective electrical position of the electric machine. The velocity observer 417 is configured to obtain a filtered image of the electrical velocity. In this case, the active low-pass filter of the Fig. 2 is removed. The effective electric speed ω according to this third embodiment corresponds to the image obtained by the speed observer.

[0088] The present invention thus makes it possible to attenuate, or even eliminate, harmonics. Furthermore, it preserves the accuracy and integrity of the position measurement by avoiding phase shift or signal attenuation. It does not generate any additional phase shift between the measured position of the rotor axis and the digitally processed position. Moreover, it allows for the calculation of harmonic-free and attenuated position and speed control signals or data. These control data, used as input for the control device, then enable very stable and precise control of the electric machine.

Claims

1. A method for determining control parameters of a rotating electric machine, including the following steps: - measuring the mechanical position θm of the axis of a rotor (5) of the electric machine (1), - constructing two imaginary two-phase signals (xα, xβ) based on the measurement of said mechanical position, said two imaginary two-phase signals being formed as two sinusoidal signals normalized and shifted from each other by 90°, characterized in that it further includes: - generating two pulse signals at the zero crossings of said imaginary two-phase signals (xα,xβ), - determining a preliminary estimate of an electrical speed, so-called the preliminary electrical speed ωest, from the sum of said two pulse signals and a maximum useful electrical frequency associated with a maximum rotational speed, - determining an open-loop estimated electrical speed ωestflt by applying a selective band-pass filter on said preliminary electrical speed ωest - injecting said two imaginary two-phase signals (xα,xβ) and said open-loop estimated electrical speed ωestfit into a phase-locked loop, and - generating, by said phase-locked loop, the actual electrical position θ of the electric machine (1).

2. The method according to claim 1, characterized in that the measurement of the mechanical position θ is carried out by a position sensor (9) mounted on the shaft of the electric machine (1).

3. The method according to claim 1 or 2, characterized in that the construction of said two imaginary two-phase signals includes the following steps: - calculating an estimate of an electrical position, so-called the estimated electrical position θ , by multiplying the mechanical position θ by the number p of pole pairs of the electric machine (1), and - calculating from said estimated electrical position θ , said two sinusoidal signals normalized and shifted from each other by 90° thereby forming said two imaginary two-phase signals.

4. The method according to any one of the preceding claims, characterized in that the determination of said two pulse signals includes the following steps: - transforming the two sinusoidal imaginary two-phase signals into square signals with a predetermined width, and - generating said two pulse signals by detecting changes in the rising and falling edges of said square signals.

5. The method according to any one of claims 1 to 4, characterized in that the generation, by said phase-locked loop, of the actual electrical position θ of the electric machine (1) includes the following steps: - applying a rotation matrix to the imaginary two-phase signals xα , xβ to extract a continuous component x of the imaginary signal according to the axis d of a rotating synchronous reference frame, - servo-controlling the continuous component x at a zero x d ∗ setpoint, - determining a corrector y based on the deviation between said setpoint and said continuous component, - determining an estimate of a phase-locked electrical speed ωPLL, by adding said corrector y to the electrical speed estimated ωestflt by the open loop, - determining an estimate of a preliminary angular position ϑv by integrating said phase-locked electrical speed ωPLL, and - determining the actual electrical position of the electric machine (1) by compensating for a delay in the estimate of the preliminary angular position ϑv of the shaft (5) of the electric machine.

6. The method according to claim 5, characterized in that it includes determining an actual electrical speed ω of the electric machine (1) by applying low-pass active filtering (217) to the phase-locked electrical speed ωPLL.

7. The method according to claim 5, characterized in that it includes determining an actual electrical speed ω of the electric machine (1) by applying selective band-pass active filtering (317) on the continuous component x of the imaginary signal according to the axis d of the rotating synchronous reference frame, the actual electrical speed ω then corresponding to the phase-locked electrical speed ωPLL.

8. The method according to claim 5, characterized in that it includes determining an actual electrical speed ω of the electric machine by applying a speed observer (417) to the actual electrical position of the electric machine, the actual electrical speed ω then corresponding to an image of the filtered electrical speed obtained by said speed observer.

9. A method for controlling a rotating electric machine comprising determining control parameters according to any one of the preceding claims10. A system for determining control parameters of a rotating electric machine, including: - a two-phase imaginary reference frame module (17) configured to construct two imaginary two-phase signals (xα, xβ) based on a measurement of the mechanical position θ of the axis of a rotor of the rotating machine received from a position sensor, said two imaginary two-phase signals being formed as two sinusoidal signals normalized and shifted from each other by 90°, and characterized in that the system further includes: - an open-loop module (19) configured to: generate two pulse signals at the zero crossings of said imaginary two-phase signals (xα, xβ); determine a preliminary estimate of an electrical speed, said preliminary electrical speed ωest, from the sum of said two pulse signals and a maximum useful electrical frequency associated with a maximum rotational speed; and determine an open-loop estimated electrical speed ωestflt by applying a selective band-pass filter on said preliminary electrical speed ωest, and - a phase-locked loop module (21) configured to generate the actual electrical position θ of the rotating machine from said two imaginary two-phase signals (xα, xβ) and using said open-loop estimated electrical speed ωestflt received from the open-loop module.

11. A device for controlling a rotating electric machine including the system (11) for determining electrical parameters according to claim 10.

12. A rotating electric machine including the control device (13) according to claim 11.