3results about How to "Reduce Harmonic Distortion Rate" patented technology

This invention discloses a method for adjusting the operating mode of a floating multi-energy complementary power generation platform system. The method includes setting the wave energy generation unit to MEC mode; setting the photovoltaic power generation unit to MPPT mode; setting the grid-side inverter unit to current source mode (VOC control mode); setting the energy storage unit converter to power generation fluctuation smoothing mode, and switching the charging and discharging states of the energy storage unit through constant power control; setting the wave energy generation unit to MEC mode or shutdown operation mode; setting the photovoltaic power generation unit to MPPT mode or constant voltage control mode; setting the grid-side inverter unit to VF control mode; and setting the energy storage unit converter to DC bus voltage stabilization control mode. This invention reduces transmission losses while minimizing the power impact on the main grid during the grid-connected operation of the island microgrid based on the power generation platform, thus improving the system's operational reliability.

The utility model belongs to motor manufacturing technical field especially relates to a rotor structure and motor, and the rotor structure includes rotor core, and the equidistribution of multiple magnetic poles has along its circumference, and each magnetic pole is provided with at least two layers of magnetic steel slot group, and each layer of magnetic steel slot group is C type structure, and each layer of magnetic steel slot group includes two separate magnetic steel slots about direct axis symmetry distribution, and the both ends of each magnetic steel slot are closed, magnetic steel is provided with multiple sections in each magnetic steel slot. The utility model is favorable for improving the magnetic field magnetic circuit of motor, reduces the harmonic distortion rate, thereby improves electromagnetic excitation, reduces motor torque ripple, realizes better motor NVH performance.

The invention discloses a grid-connected inverter stability control method based on an improved phase-locked loop, and belongs to the technical field of new energy grid-connected control, and the method comprises the steps: firstly building a grid-connected inverter impedance model, and revealing a mechanism that the phase-locked loop introduces negative damping and reduces stability margin under a weak power grid; based on an impedance model, a composite control strategy fusing dynamic feed-forward compensation and an improved Kalman observer is designed, the former actively counteracts the negative impedance effect of a phase-locked loop, and the latter improves dynamic response through state reconstruction and advanced prediction. Finally, an improved cascade delay signal elimination phase-locked loop with a selective conduction harmonic filtering function is provided, and the improved cascade delay signal elimination phase-locked loop is deeply integrated with the control strategy and a multi-harmonic feedback link, so that high-precision phase locking and active harmonic suppression are realized. According to the method, the operation stability, the dynamic performance and the electric energy quality of the grid-connected system under the conditions of high background harmonic waves and weak power grids are remarkably improved.