Abstract:
A power converter for an electrical machine drive system that includes a power source and an electrical machine including a shaft. The power converter includes a first converter coupled to the power source, a second converter coupled to the electrical machine, and at least one direct current (DC) link coupled to and between the first and second converters. The DC link includes an inductor configured to maintain a magnetic flux during system operation. The power converter also includes at least one auxiliary converter electrically isolated from the power source and the electrical machine and including an auxiliary power supply and an auxiliary inductor coupled to the auxiliary power supply and electromagnetically coupled to the inductor. The auxiliary inductor is configured to alternately energize and de-energize to alternately apply and remove, respectively, a corrective magnetic flux to the inductor to dampen harmonic oscillations of the electrical machine.
Abstract:
The subject of the invention is a method and a device for determination of a torsional deflection of a rotation shaft in the electromechanical drivetrain. The method according to the invention uses a current and voltage signals measurement of the driving electrical machine (1) and an angular speed measurement of the shaft (3) of the drivetrain and comprises the step of measuring of a voltage U DC of the DC link unit (10) of a converter (5); the step of calculating a value of a load torque T load of the driving electrical machine (1); the step of detecting of an oscillation O SC (T load ) in the load torque T load and calculation magnitudes of characteristic frequencies of Fast Fourier Transform FFT(U DC ) of the voltage U DC of DC link unit (10); the step of determining of a timestamp indicators t Tload for oscillations O SC (T load ) and t FFT of U DC for magnitudes of characteristic frequencies of FFT(U DC ) of the voltage U DC of DC link unit (10); the step of comparing the value of the timestamp indicators t Tload and t FFT and determining a torsional deflection of the rotation shaft if t Tload FFT ; the step of presenting the result of the comparison to the user in a diagnostic unit (6).
Abstract:
A dynamic linear motor is controlled by determining a relative proximity of a moving rotor of the linear motor to a fixed stator segment of the linear motor using a current location of the moving rotor. A current driving characteristic of the linear motor at the current location of the moving rotor is determined. Settings for the fixed stator segment when the moving rotor reaches the fixed stator segment are identified based on the current driving characteristic. The fixed stator segment is driven based on the settings when the moving rotor reaches the fixed stator segment.
Abstract:
Die Erfindung betrifft ein Verfahren zum Steuern eines Synchrongenerators einer getriebelosen Windenergieanlage, wobei der Synchrongenerator einen elektrodynamischen Rotor und einen Stator aufweist, zum Erzeugen elektrischer Leistung durch einDrehen des Rotors relativ zum Stator, umfassend die Schritte Erzeugen eines mehrphasigen Ausgangsstroms am Stator, Zuführen des Ausgangsstroms einem Gleichrichter,Steuern des Ausgangsstroms durch den Gleichrichter so, dass eine Drehmomentwelligkeit des Generators verringert wird.
Abstract:
A system for controlling an electric motor which includes three coils and a rotor, comprising a motion-profile-generator for generating a rotor-motion-profile and for producing a position-command, a position-controller for determining a velocity-command and a position-feedforward, for determining a forward-velocity according to the prediction of the velocity required to reach said posit ton-command. The system further includes a first summer for producing a modified velocity, a velocity controller, for determining a current-command, a velocity feedforward, for determining a forward-current and a second summer for producing a modified-current. The system also includes a commutator, for determining respective modified-coil-currents for each of at least three current-control-loops and for dividing said modified-coil-currents between the said current-control-loops according to the position of said rotor. Each current-control-loop includes a current-controller, for determining a respective voltage-command for the respective coil thereof an h-bridge for providing said voltage command to the respective coil thereof.
Abstract:
一种三相开关磁阻电机转矩脉动两电平抑制方法,在转子位置区间[0°,θ r /3]设置第一组转矩阈值,在转子位置区间[θ r /3,θ r /2]设置第二组转矩阈值,对相邻的A相和B相供电励磁,A相供电励磁比B相供电励磁超前θ r /3,A相关断,B相开通,A相到B相的整个换相过程分为两个区间,在转子位置区间[0°,θ 1 ]A相使用第二组转矩阈值,B相使用第一组转矩阈值,临界位置θ 1 是在换相过程中自动出现的,无需额外进行计算,总转矩控制在[T e +th2 low ,T e +th2 up ]之间;在转子位置区间[θ 1 ,θ r /3]A相继续使用第二组转矩阈值,B相继续使用第一组转矩阈值,总转矩被控制在[T e +th1 low ,T e +th1 up ]之间,从而抑制了三相开关磁阻电机转矩脉动。
Abstract:
A motor-drive controller has an inverter supplying an AC power to a motor, a switching angle database outputting a set of phase angles between pulses of an inverter output voltage on the basis of a current flowing to the motor. The inverter is controlled by control signals having a switching pattern on the basis of the set of phase angles, whereby the inverter output voltage has a symmetric pattern for a reduction of harmonics.