5results about How to "Suppress harmonic current" patented technology

This invention relates to the field of motor control and provides a harmonic suppression method, device, and system based on vector resonance active disturbance rejection control. The method includes the following steps: obtaining relevant parameters of a permanent magnet synchronous linear motor and establishing a current loop control model in the dq coordinate system; determining the q-axis vector resonance active disturbance rejection controller and the d-axis vector resonance active disturbance rejection controller based on the current loop control model; and obtaining the actual q-axis current i. q and the actual current i on the d-axis d ; Compare the given q-axis current with the actual q-axis current i q The difference between the input values ​​is fed into the q-axis vector resonant active disturbance rejection controller to obtain the q-axis given voltage and the d-axis given current and the actual d-axis current i. d The difference is input to the d-axis vector resonant active disturbance rejection controller to obtain the d-axis given voltage. This invention improves the traditional active disturbance rejection controller into a vector resonant active disturbance rejection controller, thereby realizing the driving of the motor and the suppression of current harmonics.

This application relates to the field of microgrid technology, and in particular to a current harmonic suppression method, an inverter, and a storage medium. The method includes: establishing the state equation of the grid-connected inverter based on the grid-connected inverter circuit and Kirchhoff's laws; establishing a transfer function from the disturbance voltage to the harmonic components of the grid-connected current based on the state equation; determining a calculation model for the modulation wave compensation term used to suppress the disturbance voltage based on the transfer function; extracting the harmonic components in the grid-connected current in real time, and obtaining the modulation wave compensation signal based on the calculation model of the harmonic components and the modulation wave compensation term; and superimposing the original modulation wave signal output by the current loop controller and the modulation wave compensation signal to obtain the final modulation wave signal. The method of this application can actively and accurately compensate for periodic voltage disturbances introduced by the switching of the power frequency bridge arm, thereby effectively suppressing the resulting current harmonics and zero-crossing distortion, and significantly reducing the THD of the grid-connected current.

The present application discloses a rectifier control method, system, device and computer-readable storage medium, which are applied to the field of rectifier control. The rectifier control method includes: obtaining the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determining the reference phase voltage among all phase voltages, and determining the phase voltages other than the reference phase voltage as the phase voltage to be adjusted; correcting each phase voltage to be adjusted so that the amplitude of the phase voltage of each phase after correction is balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage; obtaining the compensation phase voltage corresponding to each phase voltage to be adjusted; and performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages. The present application can suppress the harmonic current caused by the imbalance of the grid-side voltage amplitude.

This invention provides a three-phase single-stage multi-cavity parallel power conversion device, comprising: an AC / DC conversion circuit, the input port of which is connected to three-phase alternating current; the output port of the AC / DC conversion circuit including a first terminal, a second terminal, and a third terminal; and a DC / DC conversion circuit including at least three rectifier units, wherein the first input terminal of each rectifier unit is connected to the first terminal via a first switch, the first input terminal of each rectifier unit is connected to the second terminal via a second switch, and the first input terminal of each rectifier unit is connected to the third terminal via a third switch; the output ports of the plurality of rectifier units are connected in parallel. This invention enables power factor correction and output current or voltage regulation, improving the reliability, conversion efficiency, and power density of the power conversion device.

The invention provides a turn-to-turn short circuit fault-tolerant control method based on an open-winding five-phase FTFSCW-IPM motor, and the method comprises the following steps: building an open-winding five-phase FTFSCW-IPM motor mathematical model which comprises a flux linkage, a voltage, a torque and a motion equation; after the turn-to-turn short circuit fault is detected, an external resistor is connected, the fault reconstruction of the driving system is carried out, and a fault-tolerant control strategy is formulated for the reconstructed open-phase fault; and formulating a turn-to-turn short circuit fault-tolerant control strategy based on feed-forward compensation for the turn-to-turn short circuit fault and the open-phase fault after system reconstruction. The fault phase is connected with the external resistor, so that the short-circuit current of the fault phase can be effectively reduced, further diffusion of the fault is avoided, and stable and reliable operation of the open-winding five-phase motor driving system is ensured.