A method for controlling a converter, preferably a generator-side active rectifier of a power converter of a wind power installation, comprising: specifying a target value for the converter; specifying a carrier signal for the converter; capturing an actual value; determining a distortion variable from the target value and the actual value; and determining driver signals for the converter on the basis of the distortion variable and the carrier signal.

The present disclosure provides a method based on a motor stall protection and a motor stall protection apparatus. The method may includes: obtaining a rotational speed of a motor rotor and an output current of a motor stator; performing a pre-stall protection in response to the rotational speed being less than a first rotational speed threshold and the output current being greater than a first current threshold, the performing a pre-stall protection comprises obtaining a power module temperature, a stall decision value and a first current accumulation value; performing the stall protection in response to the first current accumulation value obtained being greater than the stall decision value. The method based on the motor stall protection provided in the present disclosure may determine a timing of performing the stall protection by periodically comparing the first current accumulation value and the stall decision value.

Provided are a motor control method, a motor control device and a variable frequency drive. The method includes: performing an amplitude limiting on a command torque to obtain a target torque; calculating a target current based on the target torque; determining whether an amplitude of the target current is greater than a current limiting amplitude; performing an amplitude limiting on current components of the target current, when the amplitude of the target current is greater than the current limiting amplitude; and controlling a motor based on the current components of the target current after being performed the amplitude limiting. Thus, an amplitude limiting on current of a motor is achieved by performing amplitude limiting on torque and current.

An embodiment of a control system includes a current command module configured to receive a torque command and output a current command for controlling a direct current (DC) motor, and a supply current limiting module configured to receive a supply current limit as an input and actively compute a motor current limit based on the supply current limit, the supply current limiting module configured to limit the current command based on the motor current limit.

According to one embodiment, a controller of a stepping motor includes a table generating unit and a current controlling unit. The table generating unit generates a data table of a threshold by using values of induced voltage at frequencies of switching signal that changes a set value of a drive current, the threshold being proportional to a frequency of the switching signal within an operation region in which the frequency of the switching signal is lower than a predetermined frequency, the values of the induced voltage including a first induced voltage generated at a first frequency of the switching signal and a second induced voltage generated at a second frequency of the switching signal. The current controlling unit controls a value of the drive current in accordance with a comparison result between the threshold and an induced voltage that is detected at a frequency lower than the predetermined frequency.

A first torque calculation unit 114 calculates torque TQ_DC currently generated by a motor 106 based on a DC current DC1. A second torque calculation unit 115 calculates torque TQ_UVW currently generated by the motor 106 based on U-phase, V-phase, and W-phase currents. A torque limit calculation unit 116 calculates a torque limit TQ_LMT1 using a torque limit characteristic map measured in advance based on a current limit DC_LMT1. A torque limit correction unit 117 compares first torque TQ_DC with second torque TQ_UVW to calculate a torque variation degree KP1. Then, the torque limit TQ_LMT1 is corrected using the variation degree KP1 to calculate a torque limit TQ_LMT2. As a result, even if required torque reaches the torque limit, the DC current does not exceed the current limit, and the output of the motor can be fully utilized by approaching the current limit.

A method performed by a control system of a power electronics converter. A first part of a grid-side current controller runs a first feedback control algorithm having a first control cycle time and includes at least proportional control using a proportional gain. A third part of the controller runs a third feedback control algorithm having the first control cycle time and acting on an output from the first control algorithm after SOA limits have been applied and includes counteracting the proportional control of the first feedback control algorithm. A second part of the controller runs a second feedback control algorithm having a second control cycle time, less than the first control cycle time, and acting on an output from the third control algorithm with the same polarity as the first control algorithm and includes proportional control using the proportional gain.

A motor controller includes a power constant controller configured to receive a target power of a permanent magnet synchronous motor (PMSM) and generate a first target speed based on the target power; a first signal generator configured to generate a second target speed; a speed constant controller switchably coupled to the power constant controller and the first signal generator, where the speed constant controller is configured to switchably receive the first target speed and the second target speed, and regulate a motor speed of the PMSM based on the received first target speed or the received second target speed; a first switch configured to switchably couple the speed constant controller to the power constant controller to receive the first target speed or the second target speed; and a first switch controller configured to control a switching state of the first switch based on the motor speed of the PMSM.

A pulse pattern generation device generating a pulse pattern for controlling switching elements provided in an inverter that operates a motor, the pulse pattern generation device includes a current calculation unit that calculates a current flowing through a coil when a voltage that is applied to the motor during the operation of the motor is virtually applied to the coil of the motor, an effective current calculation unit that calculates an effective current from the current calculated by the current calculation unit, an iron loss estimation unit that estimates an iron loss which originates in a core of the motor, and a pattern generation unit that generates a pulse pattern using an evaluation function including the iron loss estimated by the iron loss estimation unit and the effective current calculated by the effective current calculation unit as evaluation items.

A control device for controlling the current of a rotating field machine of a motor vehicle, includes a current controller for determining a fundamental of an output voltage for a respective operating point, a controller for modulating the output voltage by driving a rectifier of the control device based on a pulse pattern optimized offline for the respective operating point, and a current sensor for sampling a harmonics-impacted output current, resulting from the pulse pattern that is used, of the rectifier and for returning the sampled output current to the current controller. Sampling times for sampling the output current are optimized offline in a manner specific to the pulse pattern and are predetermined as those times at which a deviation between the harmonics-impacted output current and a fundamental of the output current is less than a predetermined threshold value.