Abstract: A method for controlling a variable speed drive comprising Ni low-voltage power cells connected in series for each phase among multiple phases, i being a phase index. The method comprises repeating P iterations comprising: activating at least one cell of one or more phases and deactivating the other power cells of the variable speed drive, wherein the at least one activated cell is selected on the basis of predefined activation controls depending on an iteration index; and receiving at least one output voltage of the variable speed drive across the terminals of the electrical device for at least one phase. The method moreover comprises, at the end of the P iterations, determining, from the measured output voltages of the variable speed drive, values of rectified voltage at the output of respective rectification stages of the power cells of the variable speed drive, and storing the rectified voltages obtained, which are respectively associated with the power cells of the variable speed drive.

Abstract: A method for controlling a variable speed drive supplying power to an electric motor, the variable speed drive comprising a plurality of at least Ni low-voltage power cells connected in series, comprising: upon reception of a speed command, determining a number Mi of cells sufficient to supply power to the motor at a target voltage V that is determined based on the speed command; and activating the Mi power cells from among the Ni power cells, and deactivating the Ni-Mi other power cells in order to supply power to the motor in accordance with the speed command.

Abstract: A method for identifying a resistance value (Rr) of the rotor of an electric induction motor (M), including determining a reference voltage (urefS) on the basis of a chosen value ({circumflex over (R)}r) for the resistance of the rotor of the electric motor, applying a control voltage (uS) to the electric motor, the control voltage being determined on the basis of the reference voltage (urefS), acquiring the values of the currents (i1, i2, i3) measured in the three phases of the electric motor, so as to deduce a stator current (iS) of the electric motor therefrom, comparing the obtained stator current (iS) with a predetermined value (irefS), correcting the value ({circumflex over (R)}r) used for the resistance (Rr) of the rotor and applying steps a) to d) until obtaining a stator current (iS) equal to the predetermined value.

Abstract: A method identifies magnetic saturation parameters of an asynchronous electric motor. The method consists in a monitoring and identification sequence including one or several iterations. The method includes applying at the input of the control law of a reference voltage or a reference flux trajectory or a reference range in order to obtain a magnetization current, building a real profile of magnetic saturation including estimate magnetization flux and measures magnetization current, and determining magnetic saturation parameters corresponding to the real profile already obtained.

Abstract: A method for controlling an electric motor, implemented in a variable speed drive, the variable speed drive being connected to the electric motor through a transformer, the method including; executing an identification sequence of the transformer for determining gain data corresponding to an inverse function of a transfer function of the transformer; generating a transfer module based on said determined gain data; determining a start-up sequence of the electric motor to be implemented by the variable speed drive by executing the transfer module on a reference current path.

Abstract: A method identifies magnetic saturation parameters of an asynchronous electric motor. The method consists in a monitoring and identification sequence including one or several iterations. The method includes applying at the input of the control law of a reference voltage or a reference flux trajectory or a reference range in order to obtain a magnetization current, building a real profile of magnetic saturation including estimate magnetization flux and measures magnetization current, and determining magnetic saturation parameters corresponding to the real profile already obtained.

Abstract: A control method implemented in a variable speed drive for starting a synchronous electric motor, said method including the application, as input, of a reference speed according to a predefined speed profile, the determination of a reference position based on the reference speed that is applied as input, the determination of a voltage in a rotating frame of reference, based on the reference speed that is applied as input, the determination of control voltages to be applied to each output phase depending, on the one hand, on the determined reference position and, on the other hand, on said voltage determined in the rotating frame of reference, and the application of the control voltages to each output phase to obtain an alignment of the position of the rotor of said motor with the reference position.

Abstract: A method for identifying a resistance value (Rr) of the rotor of an electric induction motor (M), including determining a reference voltage (urefS) on the basis of a chosen value ({circumflex over (R)}r) for the resistance of the rotor of the electric motor, applying a control voltage (uS) to the electric motor, the control voltage being determined on the basis of the reference voltage (urefS), acquiring the values of the currents (i1, i2, i3) measured in the three phases of the electric motor, so as to deduce a stator current (iS) of the electric motor therefrom, comparing the obtained stator current (iS) with a predetermined value (irefS), correcting the value ({circumflex over (R)}r) used for the resistance (Rr) of the rotor and applying steps a) to d) until obtaining a stator current (iS) equal to the predetermined value.

Abstract: A method for controlling an asynchronous electrical motor, implemented in a processing unit associated with a power converter connected to the electrical motor, the method including an identification phase, which includes generating a speed trajectory in input of a control law of the motor in order to make the speed reference take several determined successive values, for each value taken by the speed reference, determining the voltage at the terminals of the electrical motor, for each value taken by the speed reference, determining and storing the flux value for which the voltage at the terminals of the electrical motor is equal to a determined threshold value.

Abstract: A method for controlling an asynchronous electrical motor, implemented in a processing unit associated with a power converter connected to the electrical motor, the method including an identification phase, which includes generating a speed trajectory in input of a control law of the motor in order to make the speed reference take several determined successive values, for each value taken by the speed reference, determining the voltage at the terminals of the electrical motor, for each value taken by the speed reference, determining and storing the flux value for which the voltage at the terminals of the electrical motor is equal to a determined threshold value.

Abstract: A process for controlling a variable-reluctance synchronous electric motor is implemented in a processing unit coupled to a power converter connected to the electric motor. The process includes a phase of identifying a flux inductance value of the electric motor, which includes a step of generation of a reference current (?d) at the input, for each reference-current value (?d), a step of determination of a current value (?d) in the output phases, for each reference-current value (?d), a step of determination, by an identification module, of an inductance value (?dEST) as a function of a reference-current value applied at the input, of the corresponding current value measured in the output phases, and of a predetermined or variable inductance value ({circumflex over (L)}d).

Abstract: The invention relates to a control method implemented in a variable speed drive for starting a synchronous electric motor (M), said method comprising the following steps: the application, as input, of a reference speed (?s) according to a predefined speed profile; the determination of a reference position (?s) based on the reference speed that is applied as input; the determination of a voltage (Vdq) in a rotating frame of reference, based on the reference speed that is applied as input; the determination of control voltages (Va, Vb, Vc) to be applied to each output phase depending, on the one hand, on the determined reference position and, on the other hand, on said voltage determined in the rotating frame of reference; the application of the control voltages (Va, Vb, Vc) to each output phase to obtain an alignment of the position of the rotor of said motor with the reference position (?s).

Abstract: A control system included in a speed selector connected by output phases to a synchronous electric motor, the synchronous electric motor being controlled according to a control law implemented by the speed selector. A first speed of the synchronous electric motor is determined by a first speed estimator. A second speed estimator is used to determine a second speed of the synchronous electric motor. The system includes a signal generator module configured to apply, to the output phases, voltages taking account of a non-constant current signal. The second speed estimator is configured to recover the current response on the output phases, to deduce therefrom the second speed of the synchronous electric motor.

Abstract: A control method used in a control unit of a power converter, connected by three output phases to a synchronous electric motor, the method being used for starting the motor and including a first step for determining the voltages to be applied to the output phases depending on a reference current, a second step for determining a frequency to be applied to the stator depending on a stator frequency, a step for application of the first step and the second step for a given duration, so as to allow the rotor of the synchronous electric motor to rotate at the stator frequency applied. The method is particularly effective for an architecture including a transformer and a sinus filter between the power converter and the electric motor.

Abstract: A control method used in a control unit of a power converter, connected by three output phases to a synchronous electric motor, the method being used for starting the motor and including a first step for determining the voltages to be applied to the output phases depending on a reference current, a second step for determining a frequency to be applied to the stator depending on a stator frequency, a step for application of the first step and the second step for a given duration, so as to allow the rotor of the synchronous electric motor to rotate at the stator frequency applied. The method is particularly effective for an architecture including a transformer and a sinus filter between the power converter and the electric motor.

Abstract: A control system included in a speed selector connected by output phases to a synchronous electric motor, the synchronous electric motor being controlled according to a control law implemented by the speed selector. A first speed of the synchronous electric motor is determined by a first speed estimator. A second speed estimator is used to determine a second speed of the synchronous electric motor. The system includes a signal generator module configured to apply, to the output phases, voltages taking account of a non-constant current signal. The second speed estimator is configured to recover the current response on the output phases, to deduce therefrom the second speed of the synchronous electric motor.

Abstract: A power converter including a rectifier stage connected to plural phases of a network delivering an input current at a determined fundamental frequency, a DC power supply bus and a bus capacitor connected to the DC power supply bus. The converter includes a controlled current source situated on the DC power supply bus, the current source making it possible to control a rectifier current, flowing on the DC power supply bus, and a controller for the controlled current source to control a rectifier current, flowing on the DC power supply bus. The controller is configured to implement a regulation loop into which are injected a first harmonic and a second harmonic synchronized respectively at six times and twelve times the fundamental frequency of the input current delivered by the network, the amplitude and phase of these harmonics being determined to limit the THDi and the PWHD.

Abstract: A method for connecting a second motor to a variable speed drive in parallel with at least one existing motor under load and controlled by the variable speed drive is provided. The method disconnects the existing motor from the variable speed drive and a state estimator calculates transient state of the existing motor including at least the speed of the existing motor based on a previously established load model. The method then connects the second motor to the variable speed drive and the second motor is operated using a suitable directive until the actual state of the second motor attains the calculated transient state of the existing motor at a given time. Upon attaining the calculated transient state, the existing motor is reconnected to the variable speed drive such that no current spike is generated in the aforementioned process.

Abstract: A method for connecting a second motor to a variable speed drive in parallel with at least one existing motor under load and controlled by the variable speed drive is provided. The method disconnects the existing motor from the variable speed drive and a state estimator calculates transient state of the existing motor including at least the speed of the existing motor based on a previously established load model. The method then connects the second motor to the variable speed drive and the second motor is operated using a suitable directive until the actual state of the second motor attains the calculated transient state of the existing motor at a given time. Upon attaining the calculated transient state, the existing motor is reconnected to the variable speed drive such that no current spike is generated in the aforementioned process.

Abstract: A power converter including a rectifier stage connected to plural phases of a network delivering an input current at a determined fundamental frequency, a DC power supply bus and a bus capacitor connected to the DC power supply bus. The converter includes a controlled current source situated on the DC power supply bus, the current source making it possible to control a rectifier current, flowing on the DC power supply bus, and a controller for the controlled current source to control a rectifier current, flowing on the DC power supply bus. The controller is configured to implement a regulation loop into which are injected a first harmonic and a second harmonic synchronized respectively at six times and twelve times the fundamental frequency of the input current delivered by the network, the amplitude and phase of these harmonics being determined to limit the THDi and the PWHD.