Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
  • H02P27/02—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using supply voltage with constant frequency and variable amplitude
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L50/00—Electric propulsion with power supplied within the vehicle
  • B60L50/10—Electric propulsion with power supplied within the vehicle using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L50/00—Electric propulsion with power supplied within the vehicle
  • B60L50/10—Electric propulsion with power supplied within the vehicle using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines
  • B60L50/15—Electric propulsion with power supplied within the vehicle using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines with additional electric power supply
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
  • H02P23/0004—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/64—Electric machine technologies in electromobility
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Definitions

• the present invention relates to a method for controlling the power supply of a variable reluctance electrical machine, in particular for driving a motor vehicle.
• FIG. 1 shows an example of a conventional embodiment of a motor vehicle drive assembly 2.
• This assembly comprises an electric machine 6 with variable reluctance 12/8 double saliency, or
• the assembly may comprise a three-phase electrical machine variable reluctance double salient whose numbers of stator and rotor teeth are multiples of 6/4 (eg 12/8, 24/16, etc.).
• the electrical machine 6 is controlled by a power control device 1 comprising in particular a control unit 10 and an inverter 12.
• the control unit comprises in particular software means such as computer programs for governing the operation of the device 1 of power control.
• the assembly 2 furthermore comprises a position sensor and / or a speed sensor 14 enabling the unit 10 to know, at each instant, a measurement of the speed of the machine 6.
• a method of controlling such a vehicle drive assembly is used to control the torque delivered by this drive assembly.
• such a method of controlling a vehicle drive assembly has for objective, for a given supply voltage, and for a given inverter / machine unit with reluctance, to make the set of training according to certain criteria such as in particular the energy efficiency and the comfort of the vehicle (both in engine mode and generator mode).
• a first parameter denoted "INm” is a limit value that the intensity of the phase current must not exceed.
• ON is the electrical angle of initiation, that is to say the electrical angle identifying the position of the rotor at the beginning of supply of a phase of the electric machine.
• the electrical angles identifying the rotor positions change by 360 ° between two successive positions of conjunction of a rotor tooth with two consecutive stator teeth.
• the electric angle is zero when the rotor tooth considered is in conjunction with a stator tooth.
• ⁇ p is the electrical angle of supply also called “electric conduction angle", that is to say the electrical angle defining the duration of the periods of supply of a phase of the machine electric.
• This power supply is characterized by conduction angles of less than 180 ° and a limitation of the supply current to its limit value INm.
• the duty cycle of the periods of supply of a phase is less than 50%. That is, a phase is powered less than half the time when the machine operates according to a batch power control mode.
• These periods of supply are defined by closures and openings of controlled switches of the inverter. Time graphs of changes in voltage and phase supply current values are shown in Figure 4.
• a power control mode is used continuous characterized by periods of supply or conduction of the controlled switches of the inverter greater than 180 °.
• the cyclical ratio of the durations of the feeding periods of a phase is greater than 50%. That is, one phase is energized more than half the time when the machine is operating in a continuous power control mode.
• This intrinsically unstable power supply control mode is therefore for this reason avoided and is only used to achieve high torque torque-speed operating points that could not be achieved by a discontinuous power control mode.
• control unit 10 As illustrated in FIG. 1, it is known to control the control of the machine 6 by the control unit 10 by means of control laws derived from tables which give the initiation angles ON, conduction ⁇ p and the limiting current INm according to the speed of the machine obtained from the sensor 14. These quantities are also determined according to the torque to be delivered. Optionally, it will also be possible to take into account the DC supply voltage VDC of the inverter if it is likely to vary, as well as other parameters such as the temperature of the windings for example.
• a pointer is defined according to these external parameters (speed, supply voltage, winding temperature, etc.) and the torque setpoint. This pointer then addresses the parameter tables that provide the command parameters (ON, Op, INm) at low speed and (ON, Op) at intermediate speed.
• the torque delivered by the machine 6 at constant speed is proportional to the energy transmitted by a phase of the engine. It is therefore proportional to the area delimited by a curve in a phase-phase magnetic-current flow diagram.
• the energy resulting from the electromechanical conversion is thus characterized by the area (or energetic cycle) delimited by the path traveled by the phase flow and the phase current during an electric period. It can be seen that at high speed, in discontinuous power control mode, the surface of the energy cycle is very small compared to the amount of potentially usable energy, that is to say as delimited by the inductances of minimum phases (opposing teeth), maximum (teeth in conjunction), and the maximum allowable phase current INm. At low speed, however, it is found that the energy cycle is better used, the trajectory traveled delimiting almost the entire maximum area.
• the continuous supply control mode In order to increase the available torque on the motor shaft at high speed, it is proposed the continuous supply control mode mentioned above.
• FIG. 10 shows the advantage of the continuous power control mode: for the same inverter-machine assembly and the same supply voltage, a high torque gain can be obtained at high speeds.
• the batch power control mode only the operating points under the curve entitled
• FIG. 7 shows the evolution, under the effect of the application of a continuous power control mode, of the energy transmitted over several electrical periods with a constant rotation speed.
• the progressive saturation from period to period produces an increase in the energy cycle (that is to say of the defined area) and thus the available torque on the motor shaft.
• FIG. 6 illustrates, for the same operating point, the variations of magnetic flux and of the phase current during a transient phase of setting up a continuous power control mode (over about thirty cycles).
• FIG. 8 illustrates the variations in the conduction angle and the progressive increase in the average torque delivered by the machine over each electrical period, with respect to the first period, under the same operating conditions as those of FIGS. and 7.
• the gain in torque depends on:
• the continuous power control mode is advantageous in that it allows a high torque gain in high speeds.
• the average torque increases over several electrical periods before reaching its set point (unlike a conventional operation, in batch power control mode, for which the desired average torque is obtained from the first electrical period).
• the response of the system to a desired target torque is therefore unreactive.
• EP 0 534 761 proposes to stabilize operation in continuous power control mode, obtained by means of an increase of the duration of conduction of the machine beyond half an electric period, in order to take advantage of the high speed torque gain offered by this mode of operation.
• This document shows that it is possible to regulate the flow, and thus indirectly the torque, by varying the conduction angle ⁇ p. But this document merely uses pre-programmed control parameters stored in a lookup table and does not specify how the conduction angle ⁇ p is changed. A fortiori, this document does not envisage any dynamic driving law of the conduction angle ⁇ p. Furthermore, this document does not address the issue of the low reactivity of the DC mode system to achieve a set torque.
• Application FR 2 878 662 also discloses a method for controlling the power supply of an electric machine making it possible to stabilize its operation in a continuous power control mode. This method is based on a method of dynamic adjustment of the conduction angle.
• an additional stator winding is provided for this purpose which encroaches on the main winding and thus downgrades the performance of the machine in addition to requiring a second converter (in addition to the inverter). to power this additional winding.
• the optimal angles ON are deduced from FIG. 9. They correspond to the points of maximum torque and minimum of filter current for a given machine current.
• the object of the invention is to provide a method for controlling the power supply of an electric machine that obviates the aforementioned drawbacks and improves the control methods known from the prior art.
• the control method according to the invention is simple to implement and makes it possible to improve the efficiency of a drive assembly, to limit the wear and / or the dimensioning of the components of the assembly of driving and improve the comfort and driving pleasure of a motor vehicle equipped with a drive assembly powered according to the method of the invention.
• the invention also relates to a control device for implementing such a method.
• the method for controlling the power supply of a variable reluctance electric machine that can be powered according to a discontinuous power control mode or according to a control mode Continuous feed is characterized in that the machine is primarily driven according to the continuous feed control mode.
• the continuous power control mode may include successive periods of supply of the phase or phases of the engine.
• the successive periods of supply of the phase or phases of the motor may have a temporal duty cycle greater than 50%.
• the feed periods can start, at a given speed of rotation, at a constant starting angle.
• the machine is powered according to the continuous feed control mode as soon as the speed and torque conditions of the machine permit this feed control mode.
• the machine can be powered according to the batch feed control mode if the speed and torque conditions of the machine do not permit the continuous feed control mode.
• a device for controlling the power supply of a variable reluctance electrical machine is characterized in that it comprises hardware means and software means for implementing the method defined above.
• a drive assembly comprises a previously defined control device and a variable reluctance electric machine.
• a motor vehicle comprises a drive unit defined above.
• Figure 1 is a diagram of a drive assembly of a motor vehicle known from the prior art.
• Figure 2 is a diagram of a first embodiment of a drive assembly of a motor vehicle for carrying out the method according to the invention.
• Figure 3 is a diagram of a second embodiment of a drive assembly of a motor vehicle for carrying out the method according to the invention.
• Fig. 4 is a set of time graphs showing the variations of the phase supply voltage and current values of a low speed variable reluctance electric machine, which machine is fed into a batch power control mode.
• FIG. 5 is a set of time graphs showing the variations of the phase supply voltage and current values of a high speed variable reluctance electric machine, which machine is fed in a batch power control mode.
• FIG. 6 is a set of time graphs representing the variations of the magnetic flux and phase supply current values of a variable reluctance electrical machine, this machine being fed transiently according to a continuous power control mode.
• FIG. 7 is a graph showing the current phase-phase magnetic flux characteristic of a variable-reluctance electrical machine, which machine is transiently powered according to a continuous power control mode.
• FIG. 8 is a set of time graphs representing the variations of the conduction angle and of the delivered torque of a variable reluctance electrical machine, this machine being fed transiently according to a continuous power control mode.
• FIG. 9 is a set of graphs representing, for different phase currents and for two given speeds, the torque and the current flowing through a filtering capacitance of a driving assembly as a function of the initiation angle, in of continuous power control.
• Fig. 10 is a representative graph of the envelope curves of the couples in the batch power control mode and the continuous power control mode as a function of the speed. This graphic illustrates the principle on which the invention is based.
• FIG. 11 is a set of graphs showing, for two given speeds, the optimal starting angles as a function of the torque.
• the principle of the invention is to feed a variable reluctance electrical machine in a continuous power control mode as soon as possible, that is to say as soon as the operating point of the machine can be reached by the continuous power control mode. If this is not possible, the machine is fed into a batch power control mode.
• the control of the electric machine in a continuous power control mode can be implemented throughout the hatched area of FIG. 7.
• the machine will be driven according to the continuous power control mode for all the points of functioning in this hatched area.
• the machine will be driven according to the batch feed control mode.
• the hatched area is defined in its upper part by the envelope curve of the couples that can be reached in continuous power control mode and in its lower part by a dotted curve located below the envelope curve of the couples that can be reached in the batch power control mode.
• This dotted curve corresponds to the minimum torque achievable in continuous power control mode.
• the batch power control mode is mandatory. This corresponds in FIG. 11 to the intersection pairs of the two curves (dotted and continuous).
• the operating point of the machine changes statistically most often in the areas of intermediate torque. It is therefore in these areas that priority should be given to improving efficiency so as to obtain the best energy efficiency over the driving cycle.
• the shaded area previously mentioned covers precisely for a wide speed range the intermediate torque zones and it is noted that the continuous power control mode can significantly improve the performance of the drive assemblies. It follows that the fact of feeding primarily a variable reluctance electric machine improves its energy efficiency. Such priority power supply of the machine in the continuous power control mode is not described in any of the documents of the prior art mentioned above.
• the use of the DC power control mode makes it possible, in addition to improving the efficiency, to reduce the rms current which loads the filtering capacity of the inverter with respect to the effective current that would be observed if the same point was used. of operation the mode of discontinuous power control. This makes it possible either to increase the lifetime of the filtering capacity, or to reduce its size and therefore its cost.
• FIG. 9 shows that for a given machine operating as a generator (this can be generalized to any other machine, whether motor or generator), for different effective phase currents, the effective current flowing through the filtering capacitor of the inverter passes through a minimum while the ratio torque / current phase passes through a maximum. This means that for a given speed, the maximum torque is obtained with the minimum current (and therefore the minimum of joules losses or better energy efficiency). It should be noted that the losses being proportional to the square of the current, the gain in efficiency is significant. The juxtaposition of these two curves highlights that the optimal control parameters for minimize the rms current are also the optimal control parameters to maximize the energy efficiency of the electric machine. On the other hand, it can be seen that for operating points attainable in both continuous power control and batch power control mode, optimal operation is always achieved in DC power control mode.
• the drive assembly comprises a control device V provided with means for ensuring the stability of the flow and the current in the electric machine while it is in continuous supply control mode.
• a conduction angle setpoint ⁇ p adjusted to a variable reluctance machine is applied as a function of a control measure of the stability of operation of the machine in the continuous supply control mode.
• the conduction angle setpoint ⁇ p is constantly adjusted as a function of possible disturbances. Such an adjustment then makes it possible to regulate the flow so as to ensure its stability, and therefore that of the energy cycle.
• the stability measurement is a flow control measure.
• a value of the reference flow is compared to the flow estimate to obtain a flow control measure.
• the drive assembly 22 comprises a control device V differing from the control device 1 in that it comprises a means 17 for estimating the flow, a comparator 15 for calculating an error ⁇ on the flow, equal to the difference between the reference flow ⁇ commands and the estimated flow ⁇ estimated using the flow estimation means, and a corrector 16.
• This error ⁇ is processed by the corrector 16 adapted to integrate various correction laws (proportional - integral or other).
• the conduction angle ⁇ p is then modified so as to make the error ⁇ zero (the estimated flux then being equal to the setpoint flow).
• the corrector 16 can provide the additional conduction angle ⁇ p which, added to 180 °, provides the conduction angle ⁇ p greater than 180 ensuring operation in continuous power control mode.
• the conduction angle parameter ⁇ p thus obtained is supplied to the control unit 10 '.
• Flow control as described above stabilizes operation in continuous power control mode.
• the additional torque control provided by the DC mode may not be sufficiently accurate.
• it is used to determine the conduction angle parameter ⁇ p, not a flow control measure, but a torque control measure.
• the driving assembly comprises a control device 1 "having means for ensuring the stability of the torque in the electric machine while it is in a continuous feed control mode.
• variable reluctance machine a conduction angle setpoint ⁇ p adjusted according to a measure of control of the stability of the operation of the machine in continuous supply control mode.
• This measurement of the torque control measures the error ⁇ between the setpoint torque Csignal and an estimate of the torque Cestimé, which is obtained from the estimation of the flux ⁇ estimé. At a fixed speed, an estimate of the torque is determined using the estimation of the flux and then determining an estimate of the energy transmitted.
• the torque can actually be estimated by the difference between the energy transmitted during the magnetization phase and the energy returned during the demagnetization phase.
• the energy exchanged during the magnetization phase is calculated.
• the energy exchanged during the demagnetization phase is calculated.
• the converted energy corresponds to the difference of the two energies.
• the error ⁇ between the average setpoint torque and the estimated average torque is controlled by a corrector 18 which, by virtue of an appropriate law (proportional - integral, for example), provides the additional conduction angle ⁇ p making it possible to provide a conduction angle. ⁇ p above 180.
• This conduction angle parameter value is then supplied to the control unit 10 'which drives the inverter accordingly in the continuous power control mode.
• the DC power control mode can be used primarily to the batch power control mode to power the machine.
• the control unit 10 obviously comprises software means for interpreting the parameters supplied to it and for generating, consequently, control commands from the inverter, that is to say switching signals. state of the controlled switches of the inverter.
• the control unit 10 ' also comprises, unlike the control unit 10, means for determining whether it is possible to use the continuous power control mode and, if so, for apply to the inverter such a power control mode.
• the control unit 10 'further comprises means for applying to the inverter a discontinuous power control mode if this is not the case.
• the control unit 10 ' has a similar operation to the control unit 10 previously described, the conduction angle parameter ⁇ p being determined by the use of a pointer in a corner table or by interpolating values of a table of angles.
• the means for determining whether it is possible to use the continuous power control mode are, for example, of the software type and are based on the determination of the position of the operating point of the machine relative to the dotted curve of FIG.
• the control unit 10 comprises data for defining and / or characterizing this dotted curve. This data can for example be prerecorded in the control unit or be determined during a learning phase.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Control Of Electric Motors In General (AREA)

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• 2007
  • 2007-10-01 FR FR0706866A patent/FR2921772A1/fr not_active Withdrawn
• 2008
  • 2008-09-30 WO PCT/FR2008/051745 patent/WO2009050400A2/fr active Application Filing
  • 2008-09-30 EP EP08840545A patent/EP2193600A2/de not_active Withdrawn

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