A method for mitigating voltage disturbances at a point of interconnection (POI) of a grid-forming inverter-based resource (IBR) due to flicker includes receiving a voltage reference command and a voltage feedback. The voltage feedback contains information indicative of the voltage disturbances at the POI due to the flicker. The method also includes determining a power reference signal for the IBR based on the voltage reference command and the voltage feedback. Moreover, the method includes generating a current vector reference signal based on the power reference signal, the current vector reference signal containing a frequency component of the voltage disturbances. Further, the method includes generating a transfer function of a regulator based on the frequency component to account for the flicker effect. In addition, the method includes generating a current vector based on a comparison of the current vector reference signal and a current vector feedback signal. Thus, the method includes regulating a voltage vector command using the current vector to mitigate the voltage disturbances.

A method for mitigating voltage disturbances at a point of interconnection (POI) of a grid-forming inverter-based resource (IBR) due to flicker includes receiving a voltage reference command and a voltage feedback. The voltage feedback contains information indicative of the voltage disturbances at the POI due to the flicker. The method also includes determining a power reference signal for the IBR based on the voltage reference command and the voltage feedback. Moreover, the method includes generating a current vector reference signal based on the power reference signal, the current vector reference signal containing a frequency component of the voltage disturbances. Further, the method includes generating a transfer function of a regulator based on the frequency component to account for the flicker effect. In addition, the method includes generating a current vector based on a comparison of the current vector reference signal and a current vector feedback signal. Thus, the method includes regulating a voltage vector command using the current vector to mitigate the voltage disturbances.

In a method for determining the rotor position of a three-phase machine without using a rotary encoder, and to a device for controlling a three-phase motor without using a rotary encoder, the three-phase machine is fed by a converter that can be operated by pulse-width modulation, and the converter has model variables for the rotor angle and the current indicator of the three-phase machine, and the converter has device(s) by using which, in control operation, at least two values are measured which represent a measure of the local inductances of the machine which represent a measure of the local inductances of the machine, the error of the model rotor angle is determined in that, depending on the model rotor angle and the model current indicator, at least two weighting factors are determined, and in that a weighted sum is formed from the at least two measured values and the at least two weighting factors, and in that a further offset value is substracted from the sum, which is likewise determined on the basis of the model rotor angle and the model current indicator.

Multiphase generator-conversion systems are disclosed. The system includes a multiphase generator having one rotor and m+1 number of electromagnetically coupled stators, each stator having a plurality of phase legs. The system includes a converter having m+1 conversion lines, each conversion line connected to the plurality of phase legs of one of the m+1 stators. Each conversion line has a rectification module. At most m of the m+1 rectification modules has an active filtering converter. At least one of the m+1 rectification modules has a passive rectifier. At least one of the active filtering converters is configured to directly control its current to vary the magnetic flux of the stator to which it is connected and indirectly affect the magnetic flux of the rest of the stators through the electromagnetic coupling. Also disclosed are wind turbines that include generation conversion systems and methods of mitigating harmonics in multi-phase generator-conversion systems.

Multiphase generator-conversion systems are disclosed. The system includes a multiphase generator having one rotor and m+1 number of electromagnetically coupled stators, each stator having a plurality of phase legs. The system includes a converter having m+1 conversion lines, each conversion line connected to the plurality of phase legs of one of the m+1 stators. Each conversion line has a rectification module. At most m of the m+1 rectification modules has an active filtering converter. At least one of the m+1 rectification modules has a passive rectifier. At least one of the active filtering converters is configured to directly control its current to vary the magnetic flux of the stator to which it is connected and indirectly affect the magnetic flux of the rest of the stators through the electromagnetic coupling. Also disclosed are wind turbines that include generation conversion systems and methods of mitigating harmonics in multi-phase generator-conversion systems.

A system and method for sensing rotor position of a three-phase permanent magnet synchronous motor (PMSM) includes a controller coupled with the PMSM and causing a plurality of voltage pulses to be applied thereto. A timer and/or an analog-to-digital converter is coupled with the PMSM and measures a plurality of values (measured values) from a three-phase inverter coupled with the PMSM. Each measured value may correspond with one of the plurality of voltage pulses and includes a current value or time value corresponding with an inductance of the PMSM. One or more logic elements calculates, based on the measured values and on one or more position algorithms, a position of a rotor of the PMSM relative to a stator of the PMSM. The system is configured to calculate the position of the rotor when the rotor is in a stopped configuration and when the rotor is in a rotating configuration.

A system and method for sensing rotor position of a three-phase permanent magnet synchronous motor (PMSM) includes a controller coupled with the PMSM and causing a plurality of voltage pulses to be applied thereto. A timer and/or an analog-to-digital converter is coupled with the PMSM and measures a plurality of values (measured values) from a three-phase inverter coupled with the PMSM. Each measured value may correspond with one of the plurality of voltage pulses and includes a current value or time value corresponding with an inductance of the PMSM. One or more logic elements calculates, based on the measured values and on one or more position algorithms, a position of a rotor of the PMSM relative to a stator of the PMSM. The system is configured to calculate the position of the rotor when the rotor is in a stopped configuration and when the rotor is in a rotating configuration.

A system and method for sensing rotor position of a three-phase permanent magnet synchronous motor (PMSM) includes a controller coupled with the PMSM and causing a plurality of voltage pulses to be applied thereto. A timer and/or an analog-to-digital converter is coupled with the PMSM and measures a plurality of values (measured values) from a three-phase inverter coupled with the PMSM. Each measured value may correspond with one of the plurality of voltage pulses and includes a current value or time value corresponding with an inductance of the PMSM. One or more logic elements calculates, based on the measured values and on one or more position algorithms, a position of a rotor of the PMSM relative to a stator of the PMSM. The system is configured to calculate the position of the rotor when the rotor is in a stopped configuration and when the rotor is in a rotating configuration.

A motor controller includes a square wave voltage generator and adding circuitry for adding the square wave voltage to a first drive voltage that is connectable to the stator windings of a motor. A current monitor for monitoring the input current to the motor as a result of the square wave voltage. A device for determining the position of the rotor based on the input current.

A motor controller includes a square wave voltage generator and adding circuitry for adding the square wave voltage to a first drive voltage that is connectable to the stator windings of a motor. A current monitor for monitoring the input current to the motor as a result of the square wave voltage. A device for determining the position of the rotor based on the input current.