WO2018130793A1

WO2018130793A1 - Control system for a rotating electrical machine

Info

Publication number: WO2018130793A1
Application number: PCT/FR2018/050077
Authority: WO
Inventors: Luc Kobylanski; François-Xavier Bernard
Original assignee: Valeo Equipements Electriques Moteur
Priority date: 2017-01-16
Filing date: 2018-01-12
Publication date: 2018-07-19
Also published as: DE112018000391T5; CN110612662B; FR3062003B1; CN110612662A; FR3062003A1

Abstract

A control system for a multiphase and synchronous rotating electrical machine comprising a stator (31) and a rotor (30), said control system comprising: - an electronic card (16) for generating stator switching signals according to a current vector (I) in a Fresnel reference frame; - an inverter (29) capable of switching a voltage source (1) according to the stator switching signals, in order to deliver to each of the windings of the stator (8, 9, 10) a voltage and a current having an electric pulse (we), such that the stator generates a stator magnetic flux (PHI), the stator magnetic flux (PHI) having PHId and PHIq components after a Park transformation; the invention provides that, when changing from a vector control mode with amplitude width modulation (22) to a full-wave control mode (24), the inverter (29) and the electronic card (16) are configured to operate according to a control mode with a set voltage (23), wherein the inverter (29) and the electronic card (16) operate according to a control mode with amplitude width modulation in which a component Iq of the current vector (I) is controlled, the module of a corresponding voltage vector (V) having a value determined by the electronic card (16).

Description

CONTROL SYSTEM FOR A ROTATING ELECTRIC MACHINE

TECHNICAL FIELD OF THE INVENTION

The invention relates to a control system for a rotary electric machine and to its corresponding control method. This system comprises in particular an AC-DC power converter also called inverter.

The invention applies more particularly to rotating electrical machines of the type reversible polyphase, said alternator-starters, which are used in the automotive industry.

BACKGROUND TECHNOLOGY

An inverter is used to generate the polyphase currents required for the operation of a polyphase rotating electrical machine from a DC power source. Generally an inverter comprises switching elements forming a plurality of power arms, each having two switching elements in a conventional two-level bridge architecture.

The midpoint of a pair of switching elements of the same power arm is connected to a phase winding of the stator of the rotating electrical machine.

French patent application FR2745445 of the company VALEO ELECTRONIQUE discloses a rectifier bridge at the stator output of the alternator which also serves as a bridge for controlling the phases of the electric motor, the power transistors of the arms of the bridge being controlled by sequences of square signals delivered by a control unit. Such a so-called full-wave control is well known to those skilled in the art.

The switching elements can also be controlled by pulse width modulation methods known as MLI (or PWM in English, acronym for "Pulse Width Modulation"). FIG. 1 is a summary of the principle of controlling amplitude-modulated vector control, the electric machine 104 being represented in the three-phase case.

For this command, two values Id and Iq are regulated which are the components of an intensity vector in a Fresnel frame using two control values Vd and Vq which are the components of a vector voltage in a reference frame. Fresnel.

A transformation T ^"1 , for example of inverse Park, is made on the two values Vd and Vq, and voltages 100 are deduced for each of the phases From the voltages 100, switching signals 102 are determined for each of the elements of switching of an inverter 29 by a calculation 101. The switching signals 102 are calculated so that the voltages delivered on the electrical phases of the machine take the values 100. These switching signals 102 are of PWM type. inverter 29 of the currents 103 for each of the phases of the machine 104.

We then make a transformation T, for example a Park transformation to determine from currents 103, the two values Id and Iq in a Fresnel frame. The two values Id and Iq are subtracted from reference values, depending, for example, on a reference torque C of the machine and then subjected to a Proportional Integral Derivative type derivative to deduce Vd and Vq, respectively.

The French patent application FR2895598 by the company VALEO ELECTRICAL EQUIPMENT MOTOR describes a specific PWM control method of a polyphase inverter which allows both a reduction of switching losses and a reduction of an effective current in the capacitor of decoupling of to reduce the ripple of the supply voltage. It is known from the French patent application FR3004299 by the company VALEO EQUIPEMENTS ELECTRIQUES MOTEUR to change the control strategy for example according to the speed of rotation of the rotor of the rotating electrical machine. Canadian patent application CA2027983 describes a transition strategy between a MLI command to a full command with the increase of the speed of rotation. In particular, a switching between the two commands is provided when the number of hatches of the current exceeds a certain number. It is also described an analog embodiment of the transition strategy.

The Canadian patent application CA2631299 describes the establishment of a transition phase between the passage of a MLI command to full wave.

However, these two patent applications do not specify the control of the electrical variables of the machine during the transition. In general, when switching between the PWM command and the full wave command, the maximum value of the vector module voltage also called also maximum waveable voltage varies. This modulus difference of the voltage vector between the two modes prohibits a perfect transition and will generate an annoying transient current. OBJECT OF THE INVENTION

The object of the invention is to respond to this desire while at the same time remedying at least one of these aforementioned drawbacks.

According to the invention there is provided a control system for a multiphase and synchronous rotating electrical machine comprising a stator and a rotor, said control system comprising:

an electronic card for generating stator switching signals as a function of an intensity vector in a Fresnel frame;

an inverter capable of switching a voltage source according to the stator switching signals to deliver to each of the windings of the stator a voltage and an intensity having an electric pulsation, so that the stator generates a stator magnetic flux, the stator magnetic flux having PHId and PHIq components after a Park transformation;

a sensor of the currents of the phase windings of the stator; anda detector of the rotational speed of the rotor and its position; wherein the inverter and the electronic board are configured to operate in an amplitude-amplitude modulated vector control mode with a maximum wavable voltage and a modulation index having a maximum value and in a full-wave control mode with a modulation index having a fixed value,

According to a general characteristic of the invention, when switching between the amplitude-modulated vector control mode and the full-wave control mode, the inverter and the electronic board are configured to operate in accordance with a control mode. fixed voltage, in which the inverter and the electronic card operate in an amplitude-width modulated control mode in which a component Iq of the intensity vector is regulated, the modulus of a corresponding voltage vector having a value determined by the electronic card.

The fixed voltage control mode makes it possible to judiciously choose the value of the module of the voltage and by regulating the value of the intensity as a function, on the one hand, of avoiding a deviation of the voltage module when switching between the mode of amplitude-modulated vector control and full-wave control mode and secondly stable control.

For example, a fixed voltage control mode is chosen according to which, at the time of its activation from the amplitude-modulated vector control mode, the module of the voltage delivered to the stator is equal to the module of the voltage delivered. to the stator during amplitude-modulated vector control mode.

Similarly, it is possible to choose a fixed voltage control mode according to which at the moment of activation of the full wave control mode, the module of the voltage delivered to the stator is equal to the module of the voltage delivered to the stator during the full-wave control mode.

This allows a continuity of the value of the voltage module and the modulation index. However, by regulating the component Iq, it is possible with this command to regulate the value of the torque exerted by the electric machine.

According to other characteristics taken separately or in combination:

the electronic card is configured so that the fixed voltage control mode is activated when the rotational speed of the rotor exceeds a triggering speed, the amplitude-modulated vector control mode then being deactivated.

It is advisable to switch from the PWM control mode to another control mode with an increase in the speed of rotation of the electric machine. Indeed, in synchronous electrical machines, the increase in the speed of rotation corresponds to an increase in the electrical pulse making the PWM command less effective.

Thus, by providing for the activation of the fixed voltage control mode when a trigger rotation speed is exceeded, the fixed voltage control mode is inserted when the PWM command becomes less efficient.

the electronic card is configured so that the full wave control mode is activated when the rotation speed of the rotor exceeds a stop speed, the fixed voltage control mode then being deactivated.

Likewise, when according to the voltage command set the value of the modulation index or the module of the voltage vector reaches their value which they would have according to the full-wave control mode, it is possible to switch to the full-wave control mode.

according to the fixed voltage control mode, the electronic card and the inverter are configured to operate according to a control mode to amplitude-width modulation in which a Vd component of the voltage vector is controlled to regulate the Iq component, and a Vq component of the voltage vector is determined using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), wherein mod (V) = (^) xm, wherein

".. (mPO-mMLI max)

m = max MMLI H - - x (N - MAX N MLI), N being at speed

(N_PO_MIN-N_MLI_MAX) ^" 'rotation of the rotor of the machine.

It is thus possible to have a modulation index which varies between the speed of rotation N_MLI_MAX and N_PO_MIN and which takes at these two speeds respectively the value mMLI_max and mPO. This ensures a continuity in the value of the modulation index.

the electronic card is configured so that the full wave control mode is activated after an activation duration of the fixed voltage control mode, the fixed voltage control mode then being deactivated. A control mode is used which is active a certain duration DT.

according to the fixed voltage control mode, the electronic board and the inverter are configured to operate in an amplitude width modulation controlled mode in which a component Vd of the voltage vector is controlled to regulate the vector component Iq intensity, and a component Vq of the voltage vector is determined using the equation: Vq = (mod (V) ^A 2 -Vd ^A 2), in which mod (V) = x xm, in which

_" .. (mPO-mMLI max) _r _

m = mMLI_max + ¹ - xt, t G [0, DT].

It is thus possible to have a modulation index which varies between the time t = 0 and the time t = DT and which takes at these two instants respectively the value mMLI_max and mPO. This ensures a continuity in the value of the modulation index. the electronic card is configured so that the fixed voltage control mode is activated when the rotational speed of the rotor N exceeds a stop speed, the amplitude-amplitude-modulated vector control mode then being deactivated, and the fixed voltage control mode is then deactivated after a certain delay, the full wave control mode then being activated.

One uses a mode of control which is active a certain duration DT and that while the speed of rotation is N_PO_MIN, ie in principle a speed higher than N_MLI_MAX. according to the fixed voltage control mode, the voltage vector module increases linearly as a function of the rotational speed of the rotor.

There is thus a linear increase in the value of the module of the voltage delivered, which is advantageous because it makes it possible to avoid any transient effect.

according to the full-wave control mode, the electronic card and the inverter are configured so that a component Vd of the vector voltage is controlled to regulate the component Iq of the intensity vector, and a component Vq of the voltage vector is determined at using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = ^ x mPO. the rotor comprising a coil, according to the amplitude-modulated vector control mode, the inverter and the electronic card are configured to operate according to a transient control mode, in which the inverter and the electronic card operate according to an amplitude-amplitude-modulated vector control mode which regulates the Iq component of the intensity vector and in which a component Id of the intensity vector or a coil current is regulated so that the modulus of the voltage vector takes a value determined by the electronic card.

The transient control mode makes it possible to make the value of the voltage vector module tend to a value greater than what it would have been if the operating point of the PWM control mode were kept. classic vector. This allows a less marked transition to the full-wave control mode since the voltage module deviation is smaller. However, the value of the voltage vector module is less than the maximum wavable voltage so that control according to a vector PWM mode is possible.

the electronic card is configured so that the transient control mode is activated when the rotational speed of the rotor exceeds an activation speed.

the electronic card is configured so that the transient control mode is deactivated after a certain delay, the fixed voltage control mode then being activated.

the electronic card is configured so that the transient control mode is deactivated when the rotational speed of the rotor exceeds a triggering speed, the fixed voltage control mode then being activated.

according to the transient control mode, the voltage vector module increases linearly as a function of the rotational speed of the rotor.

There is thus a linear increase in the value of the module of the voltage delivered, which is advantageous because it makes it possible to avoid any transient effect. according to the transient control mode, the component Id or the coil current is regulated so that the voltage vector module takes the value of the maximum undervoltage voltage.

The transient control mode then makes it possible to set the value of the voltage vector module to the maximum value that it can expect according to a vector PWM control mode. The modulation index of the modulation index value of a full-wave control is thus brought closer together.

the electronic card determines the value of the component Id of the intensity vector by means of a function applied on the component PHId, the component PHId being determined from a maximum magnetic flux stator and the component PHIq. Thus assuming that the magnetic flux of the stator takes a maximum value and controlling the PHId component in function, one continues to regulate PHIq which is directly related to the torque of the machine while allowing the voltage vector module increases. This allows a control in which the torque developed by the machine remains around the value required by an engine control.

the electronic card during the transient control mode determines the value of the coil current by means of a function applied to the PHId component, the PHID component being determined from a maximum stator magnetic flux and from the PHIq component .

Similarly, one continues to regulate PHIq which is directly related to the torque of the machine while allowing that the voltage vector module increases since it is assumed that the flow of the stator takes its maximum value. This allows a control in which the torque developed by the machine remains around the value required by an engine control.

the PHIq component is determined using the currents in the phase windings.

For this, one can for example use a map of the rotating electrical machine. the maximum stator flux is determined by the electronic card using the maximum wavable voltage and the electric pulsation.

According to another aspect, the subject of the invention is also a control method for a multiphase and synchronous rotating electrical machine comprising a stator and a rotor, said control method comprising: a generation of stator switching signals as a function of a intensity vector I in a Fresnel landmark;

a switching by an inverter of a voltage source according to the stator switching signals to deliver to each of the stator windings a voltage and an electric pulse intensity we, so that the stator generates a stator magnetic flux PHI, the stator magnetic flux PHI having PHId and PHIq components after a Park transformation;

a measurement of the currents of the phase windings of the stator;

a detection of the speed of rotation of the rotor and of its position; a control of the inverter of the amplitude-modulated vector control type with a maximum wavable voltage and a modulation index having a maximum value; and

a control of the inverter of the full-wave control type with a modulation index having a fixed value. According to a general characteristic, the control method comprises during the transition between the control of the amplitude-amplitude modulated vector control type and the control of the full wave control type, a fixed voltage control of the inverter of the amplitude width modulation control type in which a component Iq of the intensity vector is regulated, the module of a corresponding voltage vector having a determined value .

According to other characteristics taken separately or in combination:

the fixed voltage control is activated when the rotational speed of the rotor N exceeds a triggering speed, the amplitude-modulated vector control type control being then deactivated.

the control of the full wave control type is activated when the rotational speed of the rotor N exceeds a stop speed, the fixed voltage control being then deactivated. according to the fixed voltage command, a component Vd of the voltage vector is controlled to regulate the Iq component, and a voltage vector component Vq is determined using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = (-) xm, wherein

(DFO-mMLI_max)

m = mMLI_max + x (N - N_MLI_MAX), N being the speed

(N_PO_MIN-N_MLI_MAX)

rotation of the rotor of the machine.

the control of the full wave control type is activated after a duration of activation of the fixed voltage control mode, the fixed voltage control being then deactivated.

the set voltage control a component Vd of the voltage vector is controlled to regulate the component Iq of the intensity vector, and a component Vq of the voltage vector is determined using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = - xm, in which

(DFO-mMLI_max)

m = mMLI_max + X t, t G [0, DT].

DT

the fixed voltage control is activated when the rotational speed of the rotor N exceeds a stop speed, the control of the amplitude-modulated vector control type being then deactivated and in that the fixed voltage control is then deactivated after a certain period of time, the control of the full wave control type being then activated.

according to the fixed voltage command, the voltage vector module V increases linearly as a function of the rotation speed of the rotor N. According to the full-wave control, a component Vd is controlled to regulate the component Iq, and a component is determined Vq using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = ^ x mPO.

the rotor comprising a coil, the amplitude-modulated vector control type control comprises an amplitude-amplitude-modulated vector control transient control which regulates the Iq component of the intensity vector and in which a Id component of the current vector or a coil current is regulated so that the voltage vector module takes a determined value.

the transient control is activated when the rotational speed of the rotor N exceeds an activation speed. the transient control is deactivated after a certain delay, the fixed voltage control being then activated.

the transient control is deactivated when the rotational speed of the rotor N exceeds a triggering speed, the fixed voltage control then being activated. according to the transient control, the voltage vector module increases linearly as a function of the rotational speed of the rotor N.

according to the transient control, the component Id or the coil current is regulated so that the module of the voltage vector takes the value of the maximum undulatory voltage. in the transient control, the value of the component Id of the intensity vector is determined by means of a function applied to the component PHId, the component PHId being determined from a maximum stator magnetic flux PHIM and the component PHIq.

during the transient control, the value of the coil current is determined by means of a function applied to the PHId component, the PHID component being determined from a maximum stator magnetic flux PHIM and the PHIq component.

the PHIq component is determined using the currents in the phase windings. the flow of the maximum stator PHIM is determined using the maximum waveable voltage and the electrical pulsation.

BRIEF DESCRIPTION OF THE FIGURES Other characteristics and advantages of the invention will appear on examining the detailed description of embodiments and embodiments, in no way limiting, and the appended drawings in which:

FIG 1 is a summary of the principle of a vector pulse width modulation control according to the state of the art;

FIG. 2 represents a control system for a rotating electrical machine according to the invention;

FIG. 3 represents an evolution of the modulation index according to one embodiment of the invention; FIG. 4 represents a control method for an electric machine according to one embodiment of the invention;

FIG. 5 represents a control method for an electric machine according to another embodiment of the invention;

FIG. 6 represents a control method for an electric machine according to one embodiment of the invention; and

FIG. 7 represents a control method for an electric machine according to one embodiment of the invention.

Identical, similar or similar elements retain the same reference from one figure to another. DESCRIPTION OF EXAMPLES OF EMBODIMENT OF THE INVENTION

In the rest of the description, the MLI acronym well known to those skilled in the art is used to denote pulse width modulation.

FIG. 2 illustrates a control system for a multiphase and synchronous rotating electrical machine comprising a stator 31 provided with three phase windings 8, 9 and 10, for example connected to a neutral point and a rotor 30. In the following description a voltage vector V, an intensity vector I in a Fresnel coordinate system, is defined. The voltage vector V has components Vd and Vq and can be connected by means of an inverse transform of Park at the voltages of each of the phase windings 8, 9 and 10 and the neutral point as appropriate. Similarly, the intensity vector I has components Id and Iq and is obtained using a Park transform on the intensities of each of the phase windings. The control system includes:

a sensor 15 of the currents of the phase windings of the stator.

an electronic card 16 for generating stator switching signals. These stator switching signals are generated as a function of the intensity vector I in a Fresnel frame. For example, the control voltage vector V is first calculated from the intensity vector I and the generation of stator switching signals is made from this control voltage vector V. The electronic card is for example equipped with a microprocessor 17.

an inverter 29 capable of switching a voltage source 1 supplying a DC voltage Vdc as a function of the stator switching signals in order to deliver to each of the phase windings of the stator 8, 9, and 10 a voltage and an electric pulse intensity we, so that the stator generates a stator magnetic flux PHI, the stator magnetic flux PHI having PHId and PHIq components after a Park transformation. According to this exemplary embodiment, the inverter 29 comprises three arms which are connected to the three phase windings respectively. Each arm comprises two transistors 2A, 2B, 4A, 4B, 6A, 6B and two diodes 3A, 3B, 5A, 5B, 7A, 7B. The diodes 3A, 3B, 5A, 5B, 7A, 7B are connected in parallel with the transistors 2A, 2B, 4A, 4B, 6A, 6B, respectively. The electronic card 16 is configured to transmit a stator switching signal to each of these transistors.

a detector 14 of the position and the speed of rotation of the rotor, also called the speed of rotation of the machine, for example the detector 14 comprises a module with Hall effect sensors. The rotor 30 comprises for example a coil 13 for generating a magnetic rotor flux PHIr intended to interact with the magnetic stator flux PHI, said coil 13 being fed by a coil current Ir, the coil current being generated by a rotor switching system 12 which modulates the voltage of the voltage source 1. The rotor switching system 12 is made for example by a transistor. The electronic board 16 is configured to output a rotor switching signal to the rotor switching system 12 to regulate the coil current, a diode 11 being connectable in parallel with the coil.

The electronic board and the inverter are configured to operate in amplitude-modulated vector control mode 22 with a maximum wavable voltage V_maxMLI and a modulation index m with a maximum value mMLI_max and in a full-wave control mode 24 with a modulation index m having a fixed value mPO.

According to the amplitude-modulated vector control mode 22, it is possible for example to provide that the two regulated values are the components Id and Iq of an intensity vector and that the two control values are the two components Vd and Vq. of a voltage vector, the voltage vector and the intensity vector being expressed in a Fresnel frame.

In this case, in a manner similar to the principle illustrated in FIG. 1, the electronic card will calculate from the currents of the phase windings of the stator using a Park transform, the components Id and Iq. Then, according to these values Id, Iq and functions relating to the operation of the electric machine such as in particular a torque to be exerted by the machine and the speed of rotation indicated by the detector 14, the electronic card will deduce the two values of commands Vd and Vq. The electronic card then applies an inverse Park transform to determine the corresponding polyphase voltages and the potential of the neutral point if necessary and to deduce the stator switching signals which are PWM signals.

The modulation index m then complies with the equation below: m = <mMLI max. The amplitude modulated vector control mode has a maximum wavable voltage V_maxMLI corresponding to the maximum acceptable module of the voltage vector. V_maxMLI has a value of ^ in the three-phase case. According to the full wave control mode 24, it is provided that the stator switching signals have a square shape and are of fixed width. These signals correspond to a voltage vector in a Fresnel frame whose only phase is adjustable and whose amplitude is fixed.

For example, in full-wave control mode, the board and the inverter are configured so that the Vd component of the voltage vector is controlled to regulate the Iq component of the intensity vector, and the Vq component of the voltage vector is determined. using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = ^ x mPO, mod (V) corresponding to the vector V modulus.

Thus, knowing the shape of the full-wave phase signal and considering the fundamental of this signal, the modulus of the vector voltage in a Fresnel frame is fixed and is equal to ^^. _m

The difference between λ and corresponds to the deviation of the modulus of the voltage vector V between the two PWM and full wave modes already mentioned in the introduction of the subject of the invention.

The modulus of the voltage vector can be directly linked to the modulation index m according to the formula: m = in which mod (V) represents the modulus of the voltage vector V. Thus mMLI_max and mPO are respectively equal to - = and ^ according to this embodiment.

FIG. 3 illustrates the evolution of the modulation index m as a function of the speed of rotation of the rotor and as a function of the modulation mode. More precisely, FIG. 3 represents two curves 27 and 28 in a reference frame comprising an axis 19 corresponding to the value of the modulation index and an axis 18 corresponding to the value of the speed of rotation of the machine.

The curve 27 corresponds to the maximum value that can take the modulation index, this value depends in particular on the control mode of the rotating electrical machine.

Curve 28 corresponds to the value of the modulation index, the modulation index being directly connected to the voltage vector module, by the aforementioned formula: m = ^{mod (v)}

Vdc / 2

When switching between the amplitude-modulated vector control mode 22 and the full-wave control mode 24, the inverter and the electronic board are configured to operate in a fixed voltage control mode 23. This mode of fixed voltage control 23 plays the role of transition between the two control modes which mutually have a modulus of variation of the vector or a variation of modulation index.

As can be seen in FIG. 3, during amplitude-modulated vector control mode 22, the modulation index m is variable and can take the maximum value: mMLI_max. Thus, the curve 27 is superimposed with the value mMLI_max. While in the full-wave control mode 24 delimited by the interval 24 in FIG. 3, the modulation index m has a fixed value mPO which is superimposed with the curve 27 and also the curve 28.

In the fixed voltage control mode 23 delimited by the interval 23 in FIG. 3, the modulation index m has a variable value between mMLI_max and mPO.

According to the fixed voltage mode, the intensity of the intensity vector as a function of the intensities in each of the stator phase windings is determined by Park transform, and then the control components Vd and Vq are determined. An inverse Park transform is then carried out to determine the voltage values at the terminals of each windings and the neutral point, where appropriate, from which the stator switching signals for each of the arms of the inverter are derived.

More precisely, the component Iq of the intensity vector I is regulated by means of pulse width modulation using the voltage vector V as a control, the voltage vector module V having a value determined by the electronic card.

According to a first example, the Vd component of the voltage vector is controlled to regulate the Iq component according to a pulse width modulation control, and the Vq component of the voltage vector is determined using the equation: Vq = V (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = (^) xm, in which m = mMLI max + ^{(mP0 ~ mMLI} - ^max) χ (N-N MAX ML), (EQUATION 1)

(N_PO_MIN-N_MLI_MAX) - - y. \ /

N being the rotational speed of the rotor of the machine.

Thus, the value of the voltage vector module is fixed using the modulation index. The modulation index being determined using the speeds of N_PO_MIN, N_MLI_MAX, mPO and mMLI_max and a value proportional to the speed of rotation.

According to a second example, the Vd component of the voltage vector is controlled to regulate the Iq component of the intensity vector, and the Vq component of the voltage vector is determined using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), where mod (V) = ^ xm, where m = m_i + xt, t G [0, DT]. (EQUATION 2) with -m_i representing the initial value of the modulation index during the fixed voltage control and taking in order to ensure the continuity of the modulation index, the value of the modulation index m at the time of the switching from the vector PWM type control mode 22 to the fixed voltage control mode 23, for example m = mMLI_max

-m_f representing the final value of the modulation index during the fixed voltage control and taking the value m_f = mPO to ensure continuity of the modulation index when switching to the full wave mode.

-DT corresponds to a duration of time. For example DT corresponds to the duration of activation of the fixed voltage control mode.

Thus, the value of the voltage vector module is fixed using the modulation index. The modulation index being determined using mPO and mMLI_max and DT which is equal to the duration given to the fixed voltage control mode 23 for changing the modulation index by an equal value, for example at the maximum modulation index of the pulse width modulation to the value of the full wave modulation index, mPO.

According to the first and second examples, the two values of control variables Vd and Vq of the pulse width modulation are thus available in order to regulate the current vector I of components Id and Iq.

According to the first and second examples, in order to regulate Iq using the command Vd, it is possible, for example, to connect Vd to Iq, using the formulas connecting the fluxes to the intensities in a rotating electrical machine, considering the permanent mode only, that is to say by canceling ^ in a formula of the type Vd = R x Id + L x ^ - we x Fu, in which R represents the resistance of the stator windings, we the electrical pulsation, Fu the magnetic flux of the stator and L the inductance of the stator windings.

Moreover, since the value of the voltage vector module is directly related to the modulation index m, in the case of the first example, the value of the voltage vector module increases linearly as a function of the rotational speed of the rotor N. Similarly, for the second example, in the case where the rotational speed of the rotor increases linearly with time, that is to say along a ramp then the value of the voltage vector module increases linearly as a function of the speed of rotation of the rotor. According to the speed of the electric machine, the amplitude-modulated vector control mode 22 is active on the interval represented in FIG. 3 up to a triggering speed N_MLI_MAX and the operating mode Full wave control 24 is active on the slot 24 from a stop speed N_PO_MIN in Figure 3. For example, N_MLI_MAX is a value set by a period number of the PWM signal in an electrical period. One can for example choose, N_MLI_MAX = 4500 rpm.

For example, N_PO_MIN is a value set according to the F.E.M of the electric machine so that the current in the electric machine is not too big. One can for example choose, N_PO_MIN = 5000 rpm.

Between amplitude-modulated vector control mode 22 and full-wave control mode, there is provided the fixed voltage control mode 23 which is active on the gap 23 in FIG.

In other words, the electronic card is configured on the one hand so that the fixed voltage control mode 23 is activated when the rotational speed of the rotor N exceeds the triggering speed N_MLI_MAX, the modulated vector control mode amplitude width 22 is then deactivated and secondly so that the full wave control mode 24 is activated when the rotational speed of the rotor N exceeds the stop speed N_PO_MIN, the fixed voltage control mode 23 being disabled.

According to another embodiment, it can be provided that the electronic card is configured so that the fixed voltage control mode is activated when the rotational speed of the rotor N exceeds a stop speed N_PO_MIN or the triggering speed N_MLI_MAX, the vector control mode amplitude amplitude modulation being then deactivated and the fixed voltage control mode is then deactivated after a certain delay for example DT, the full wave control mode then being activated.

It can also be provided as illustrated in FIG. 3 that the amplitude-modulated vector control mode 22 comprises two operating modes delimited respectively by the intervals 25 and 26 in FIG.

The interval 25 delimits the vector control mode with conventional amplitude width modulation 25 according to which it is expected to calculate according to the currents Id and Iq, a vector V in order to optimize the efficiency of the machine for example.

The interval 26 delimits a transient control mode 26 according to which the components Id and Iq of the intensity vector I or the component Iq and the coil current Ir are regulated, the module of the voltage vector having a value determined by the electronic card. In other words, according to the transient control mode, the component Iq being regulated, the component Id of the intensity vector I or a coil current Ir is regulated so that the module of a corresponding voltage vector V takes a determined value.

More precisely, the transient control mode 26 is a vector PWM control mode in which the voltage vector V is used as control for the regulation of the components Id and Iq or the component Iq and the coil current Ir.

For example, it is possible to predict that the modulus of the voltage vector is determined by another relationship explained below. In any case, the value of the voltage vector module is less than or equal to the maximum undervoltage voltage. That is, the voltage vector module is less than or equal to dans in the case of a three-phase electric machine.

According to a first example, it can be provided that according to said other relation the voltage module takes the value of the maximum undulating voltage. That is, the voltage vector module is equal to dans in the case of a three-phase electric machine. According to the first example, it is possible, in a first case, to determine the value of the component Id of the intensity vector using a function applied to the component PHId. For this, the function connecting PHId and Id is determined by means of a cartography previously carried out on the rotating electrical machine and which is stored in the control card 16.

According to the first example, it is possible in a second case to determine the value of the coil current of the rotor Ir by means of a function applied to the component PHId. For this purpose, the function connecting PHId and Ir is determined using a cartography previously carried out on the rotating electrical machine and stored in the control card 16.

According to the first and second cases, the PHId component can be determined from a maximum stator magnetic flux PHIM and PHIq component. For this, we can use the formula:

PHId = (PHIm ^A 2 - PHIq ^A 2). According to the first and second cases, the PHIq component is determined using the currents in the phase windings. For example, the PHIq component is determined as a function of Iq, PHiq = G (lq). To determine the function G, it is possible, for example, to use a pre-mapping of the rotating electrical machine which is stored in the control card 16.

Moreover, according to the first and second cases, the flow of the maximum stator PHIM is determined by the electronic card using the maximum wavable voltage V_maxMLM and the electric pulse we. More precisely, we can use the formula PHIm = ^v - ^maxMU

we For the first and second cases, according to a way of calculation, we can determine a function F by mapping, according to which, PHId = F (ld + k.lr), with k a constant. Thus by fixing the relative value of the component Id with respect to Ir, one can according to this way of calculation, determine the component Id and the value of the current Ir as a function of PHId. In other words, according to an embodiment of the first example, PHIM can be determined with the formula PHIm = ^v - ^maxMLI determine PHIq at

we

using the formula PHiq = G (lq), from which one can deduce PHId and by inverting the function F, ie by applying the function F ^"1 , one deduces Id and Ir with a fixation of the value relative of the component Id with respect to the current Ir.

With the aid of the components Id and Iq, the value of the two control variables of Vd and Vq of the vector pulse width modulation control is deduced so that the voltage vector module is V_maxMLI.

According to a second example, as illustrated in FIG. 3, according to said other relation, the modulus of the mod vector voltage (V) increases linearly as a function of the rotation speed of the rotor N, without being greater than the maximum undulating voltage. That is, the voltage vector module is less than λ in the case of a three-phase electric machine.

One can for example apply the calculations used for the first example for a large number of rotational speeds of the electric machine with the formula PHIm = ^{mod (v}

we

According to this second example, it is possible to provide for the activation of the transient control mode to choose a voltage vector module equal to that obtained by the conventional vector PWM 25 so as to ensure a continuity of the modulation index.

The activation of the transient control mode 26 is for example triggered by the speed of rotation of the rotor N which exceeds an activation rate N_MLI_OPTI_MAX.

It is possible, for example, to provide that N_MLI_OPTI_MAX is a value fixed not too far from N_MLI_MAX when a fixed voltage control mode 23 is provided in addition to the transient mode so as not to degrade the efficiency too much. When a fixed voltage control mode 23 is not provided in addition to the transient mode, one can for example choose N_MLI_MAX with respect to N_PO_MIN. However, we can choose example N_MLI_OPTI_MAX = 4300 rpm. With regard to the deactivation of the transient control mode, it is possible, for example, to configure the electronic card so that the transient control mode is deactivated after a certain delay, the fixed voltage control mode being then activated. It is also possible that the electronic card is configured so that the transient control mode is disabled when the rotational speed of the rotor N exceeds a triggering speed N_MLI_MAX, the fixed voltage control mode then being activated.

However, it is possible according to another embodiment, as in the corresponding method illustrated in FIG. 6, to provide that the amplitude-modulated vector control mode 22 comprises the vector control mode with conventional amplitude width modulation. 25 and transient control mode 26 without there being a fixed voltage control mode 23. In other words, in this embodiment, one passes directly from the transient control mode 26 belonging to the mode of control. amplitude-amplitude modulation vector control 22 to the full wave control mode 24. In this embodiment, it is possible, for example, to provide a transient mode according to the first or second case of the first example, that is to say in particular with the vector module voltage equal to ^ in the case of a three-phase electric machine.

In FIG. 3, one can also see intervals 21 and 20 which respectively correspond to a vector-type command 21 and to a scalar-type command. The interval 21 corresponds to the interval 22 of amplitude-modulated vector control mode. Indeed, in the amplitude-amplitude vector control mode, it is intended to regulate two quantities namely Id and Iq using two magnitudes Vd and Vq, for example.

The interval 22 includes in particular the interval 26 which is a PWM vector control mode. Indeed, according to the transient control mode the values Id and Iq or Ir and Iq are regulated using the MLI so that the V voltage vector module takes a determined value. However, according to the transient control mode, the value of the voltage vector module is less than the maximum value that can be obtained with a vector pulse width modulation. This value, also called maximum wavable voltage V_maxMLI is equal to ^ in the case of a three-phase electric machine.

The interval 20 corresponds to the interval 23 and also to the interval 24.

Indeed, the full-wave control mode 24 is a scalar control mode in which only one parameter is regulated since a voltage vector is used as control, of which only the phase is variable.

Similarly, the fixed voltage control mode 23 is a scalar control mode in which only one of the two components of the intensity is regulated by PWM modulation the other component taking an incident value due to the setting of the value of the voltage vector module. According to the fixed voltage control mode, the value of the voltage vector module is greater than that which can be obtained with a vector pulse width modulation also called the maximum wavable voltage V_maxMLI. The maximum waveable voltage is equal to ^ in the case of a three-phase electric machine. FIG. 4 illustrates a control method for an electric machine according to one embodiment of the invention. This includes the following steps:

22: amplitude-amplitude modulated vector control mode 22 which comprises both sub-steps 25 and 26. in step 25: the aforementioned conventional amplitude-width modulated vector control mode according to which provision is made for calculate according to the currents Id and Iq, a vector V to optimize the efficiency of the machine for example. in step 26: the transient control mode 26 above. According to which, according to the first example comprising the first and the second case As explained above, it is possible for the module to take the modulus of the vector voltage equal to dans in the case of a three-phase electric machine. According to the second example explained above, the modulus of the mod vector voltage (V) increases linearly as a function of the rotational speed of the rotor N. 23: the fixed voltage control mode 23 mentioned above. According to the above-mentioned first and second examples, the component Vd of the voltage vector is controlled to regulate the component Iq according to a pulse width modulation command, the modulus of the voltage vector mod (V) is fixed and determined. the component Vq of the vector voltage using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = (^) x m. The modulation index can be determined using Equation 1 or Equation 2.

24: the wave control mode 24 above. According to which, as already mentioned, the Vd component of the voltage vector is controlled to regulate the Iq component of the intensity vector, and the Vq component of the voltage vector is determined using the equation: Vq = (mod (V ) ^A 2 - Vd ^A 2), in which mod (V) = ^ x mPO.

For example, the transient control 26 is activated when the rotational speed of the rotor N exceeds an activation speed N_MLI_OPTI_MAX.

It can be provided that the transient control 26 is deactivated after a certain period of time, the fixed voltage control 23 then being activated.

Provision can also be made for the transient control 26 to be deactivated when the rotational speed of the rotor N exceeds a triggering speed N_MLI_MAX, the fixed voltage control 23 then being activated.

For example, the fixed voltage control 23 is activated when the speed of rotation of the rotor N exceeds a triggering speed N_MLI_MAX, the amplitude-modulated vector control type control 22 is then deactivated.

It is also possible for the control of the full wave control type 24 to be activated when the rotational speed of the rotor N exceeds a stop speed N_PO_MIN, the fixed voltage control 23 then being deactivated.

According to another embodiment, the fixed voltage control 23 is activated when the rotational speed of the rotor N exceeds a stop speed N_PO_MIN or the triggering speed N_MLI_MAX, the control of the amplitude-modulated vector control type being then deactivated and the fixed voltage control 23 is then deactivated after a certain period of time, the control of the full wave control type then being activated.

Figure 5 illustrates a control method for an electric machine according to another embodiment of the invention. This is distinguished in that it does not include the fixed voltage control mode 23, so it comprises the following steps:

22: the amplitude-width modulated vector control mode 22 which comprises the two sub-steps 25 and 26 which are similar to those of the embodiment illustrated in FIG. 4.

24: the full wave control mode 24 full wave control mode which is similar to that of the embodiment illustrated in Figure 4.

For example, the transient control 26 is activated when the rotational speed of the rotor N exceeds an activation speed N_MLI_OPTI_MAX. It can be provided that the transient control 26 is deactivated after a certain delay, the full wave control mode 24 then being activated.

It is also possible that the transient control is deactivated when the rotation speed of the rotor N exceeds a triggering speed N_MLI_MAX, the full wave control mode is then activated. As illustrated in FIG. 6, the method further comprises the following steps:

32: a generation of stator switching signals as a function of an intensity vector I in a Fresnel frame; 33: a switching by an inverter of a voltage source according to the stator switching signals to deliver to each of the stator windings a voltage and an intensity,

34: a measurement of the currents of the phase windings of the stator. This measurement is performed for example using the current sensor 15. 35: a detection of the rotational speed of the rotor N. This detection is performed for example using the detector 14 of the rotational speed of the rotor.

For example, each of the steps or sub-steps 25, 26, 23, and 24 of the method illustrated in FIG. 4 or 25, 26, and 24 of the method illustrated in FIG. 5 comprises the steps 32, 33, 34 and 35 mentioned herein. above.

Whatever the steps or in steps 25, 26, 23, and 24 of the process illustrated in FIG. 4 or 25, 26, and 24 of the method illustrated in FIG. 5, during step 32, it is determined by transforming Park the components Id and Iq of the intensity vector as a function of the intensities measured during step 31 in each of the stator phase windings, and then the value of the control components Vd and Vq are determined. To determine these components one can use a Proportional Integral Derivative type corrector as shown in Figure 1 in principle of a MLI command. In this case, it will be necessary to initialize these correctors during the transition from one control mode to another. An inverse Park transform is then performed to determine the voltage values across each of the windings and the neutral point, where appropriate, from which the stator switching signals for each of the arms of the inverter are derived.

FIG. 7 illustrates, according to one embodiment, the passages between the different control modes: vector PWM type control mode 22, fixed voltage control mode 23 and the full control mode 24. The passages are numbered 2223, 2324, 2423 and 2322 depending on the number of the initial command mode and the control mode to which one passes.

According to the vector PWM control mode 22, the modulation index is connected to the voltage vector according to the following formula:

V (Vq ² + Vd ² ) ^. ..

m = - ^L - ⁱ <mMLI max.

Vdc / 2

According to the full-wave control mode, the modulation index which takes a fixed value mPO, for example equal to ^ and we can connect Vq to Vd using the formula Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = ^ x mPO.

According to the passage 2223, one switches from the vector PWM type control mode 22 to the fixed voltage control mode 23 when the speed of rotation of the rotating electrical machine is greater than the stop speed N_PO_MIN. In fixed voltage control mode, then the modulation index is used to determine the following: m = m _{J +} ^^ xt, t G [0, DT]. with

-m_i taking the value of the modulation index m at the time of the passage of the control mode of MLI vector type 22 to the fixed voltage control mode, for example m = mMLI_max

-m f = mPO

t = 0

-DT corresponds to a duration of time. For example DT corresponds to the duration of activation of the fixed voltage control mode. According to the passage 2324, one passes from the fixed voltage control mode 23 to the full wave control mode 24 when the speed of rotation of the rotating electrical machine is greater than the stop speed N_PO_MIN and t = DT. According to the passage 2423, one goes from the mode of full wave control 24 to the fixed voltage control mode 23 when the speed of rotation of the rotating electrical machine is lower than the stop speed N_PO_MIN. We then apply to determine the modulation index: m = m _{J +} ^^ xt, t G [0, DT]. with

-m_i = mPO -m_f = mMLI_max -t = 0

According to the passage 2322, one passes from the fixed voltage control mode 23 to the vector PWM control mode 22 when the speed of rotation of the rotating electrical machine is lower than the stop speed N_PO_MIN and t = DT.

Claims

1. A control system for a multiphase and synchronous rotating electrical machine comprising a stator (31) and a rotor (30), said control system comprising: an electronic card (16) for generating stator switching signals according to a vector intensity (I) in a Fresnel frame;

an inverter (29) able to switch a voltage source (1) according to the stator switching signals to supply to each of the stator windings (8, 9 10) a voltage and an intensity having an electric pulse (we), so that the stator generates a stator magnetic flux (PHI), the stator magnetic flux (PHI) having PHId and PHIq components after a Park transformation;

a sensor (15) of the currents of the phase windings of the stator (8, 9, 10); anda detector (14) of the rotational speed of the rotor (N) and its position; wherein the inverter (29) and the electronic board (16) are configured to operate in amplitude-modulated vector control mode (22) with a maximum wavable voltage (V_maxMLI) and a modulation index (m ) having a maximum value (mMLI_max) and a full wave control mode (24) with a modulation index (m) having a fixed value (mPO), characterized in that when switching between the modulated vector control mode amplitude width (22) and the full wave control mode (24), the inverter (29) and the electronic board (16) are configured to operate in a fixed voltage control mode (23), according to which the inverter (29) and the electronic card (16) operate in an amplitude-width modulated control mode in which a component Iq of the intensity vector (I) is regulated, the modulus of a vector voltage (V) correspondent having a value determined by the electronic card (16).

2. Control system according to the preceding claim, characterized in that the electronic card (16) is configured so that the fixed voltage control mode (23) is activated when the rotational speed of the rotor (N) exceeds a speed trigger (N_MLI_MAX), the vector control mode amplitude modulation modulation (22) is then disabled.

Control system according to claim 1 or 2, characterized in that the electronic card (16) is configured so that the full wave control mode (24) is activated when the rotational speed of the rotor (N) exceeds a stop speed (N_PO_MIN), the fixed voltage control mode (23) then being deactivated.

4. Control system according to the preceding claim when dependent on claim 2, characterized in that according to the fixed voltage control mode (23), the electronic card (16) and the inverter (29) are configured to operate according to an amplitude width modulated control mode in which a voltage vector component Vd is controlled to regulate the Iq component, and a voltage vector component Vq is determined using the equation: Vq = (mod ( V) ^A 2 - Vd ^A 2), wherein mod (V) = ()) xm, wherein

".. (mPO-mMLI max)

m = max MMLI H - - x (N - MAX N MLI), N being at speed

(N_PO_MIN-N_MLI_MAX) ^" 'rotation of the rotor of the machine.

5. Control system according to claim 1 or 2, characterized in that the electronic card (16) is configured so that the full wave control mode (24) is activated after an activation time (DT) of the control mode. fixed voltage control (23), the fixed voltage control mode (23) then being deactivated.

6. Control system according to the preceding claim, characterized in that according to the fixed voltage control mode (23), the electronic card (16) and the inverter (29) are configured to operate in a modulating control mode of amplitude width in which a component Vd of the vector voltage is controlled to regulate the component Iq of the intensity vector, and a component Vq of the voltage vector is determined using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = ^ xm, in which

. .. . (mPO-mMLI max) _ _r "" _,

m = mMLLmax + ¹ xt, t G [0, DT].

7. Control system according to claim 1, characterized in that the electronic card (16) is configured so that the fixed voltage control mode is activated when the rotational speed of the rotor (N) exceeds a stop speed (N_PO_MIN), the amplitude-modulated vector control mode (22) is then deactivated and in that the fixed voltage control mode (23) is then deactivated after a certain delay, the full-wave control mode (24) then being activated.

8. Control system according to one of the preceding claims, characterized in that according to the fixed voltage control mode (23), the voltage vector module (V) increases linearly as a function of the rotational speed of the rotor (N ).

9. Control system according to one of the preceding claims, characterized in that according to the full wave control mode (24), the electronic card (16) and the inverter (29) are configured so that a component Vd of vector voltage (V) is controlled to regulate the component Iq of the intensity vector (I), and a component Vq of the voltage vector (V) is determined using the equation: Vq = (mod (V) ^A 2 - Vd ^A 2), in which mod (V) = ^ x mPO.

10. Control system according to any one of the preceding claims, characterized in that the rotor comprising a coil (13), according to the amplitude-modulated vector control mode (22), the inverter and the card are configured to operate according to a transient control mode (26), in which the inverter (29) and the electronic board (16) operate in an amplitude-width modulated vector control mode which regulates the Iq component of the intensity vector (I) and in which a component Id of the intensity vector (I) or a coil current (Ir) is regulated so that the voltage vector module (V) takes a value determined by the electronic card.

1 1. Control system according to Claim 10, characterized in that the electronic card (16) is configured so that the transient control mode (26) is activated when the rotational speed of the rotor (N) exceeds an activation speed ( N_MLI_OPTI_MAX).

Control system according to Claim 10 or 11, characterized in that the electronic card (16) is configured so that the transient control mode (26) is deactivated after a certain delay, the fixed voltage control mode being activated.

Control system according to Claim 10 or 11, characterized in that the electronic card (16) is configured such that the transient control mode (26) is deactivated when the rotational speed of the rotor (N) exceeds a triggering speed (N_MLI_MAX), the fixed voltage control mode (23) then being activated.

14. Control system according to one of claims 10 to 13, characterized in that according to the transient control mode (26), the voltage vector module (V) increases linearly as a function of the rotational speed of the rotor (N ).

15. Control system according to one of claims 10 to 13, characterized in that according to the transient control mode (26) the component Id or the coil current (Ir) is regulated so that the voltage vector module (V ) takes the value of the maximum waveable voltage (V_maxMLI).

16. Control system according to the preceding claim, characterized in that the electronic card (16) determines the value of the component Id of the intensity vector by means of a function (F ^"1 ) applied to the component PHId, the PHId component being determined from a maximum magnetic flux stator (PHIm) and PHIq component.

17. Control system according to claim 15, characterized in that the electronic card (16) during the transient control mode (26) determines the value of the coil current (Ir) by means of a function (F ^"1 ) applied to the component PHId, the component PHId being determined from a maximum magnetic stator flux (PHIm) and the component PHIq.

18. Control system according to claim 16 or 17, characterized in that the PHIq component is determined using the currents in the phase windings (8, 9, 10).

19. Control system according to one of claims 16 to 18, characterized in that the maximum stator flux (PHIm) is determined by the electronic card (16) using the maximum wavable voltage (V_maxMLI) and the electric pulse (we).