2results about How to "Applicable frequency range is wide" patented technology

The application discloses a grid-connected inverter current harmonic suppression method and system based on wide-frequency virtual inductance, relates to the technical field of current transformer control, and solves the problem that existing technologies do not have the ability of inter-harmonic suppression, resulting in the problem that the harmonic suppression effect of the grid-connected inverter is reduced or even invalid. The application constructs an additional control loop for the non-power frequency component of the inverter output current, introduces wide-frequency virtual inductance in the additional control loop to increase the equivalent output impedance of the grid-connected inverter, so that the wide-frequency harmonic current of the grid-connected inverter under the grid voltage distortion condition is suppressed. The application can suppress the harmonic current of the grid-connected inverter caused by the integer harmonic and unknown frequency inter-harmonic in the grid voltage without harmonic frequency detection or pre-known harmonic frequency, so that the adaptability of the grid-connected inverter harmonic suppression under the complex grid condition is improved.

This invention addresses the technical problems of insufficient vibration noise suppression and limited measurement accuracy in existing cold atom interferometric gravimeters by proposing a cold atom interferometric gravimeter and its gravity measurement method that uses a laser interferometer to monitor vibration noise. The invention includes a laser interferometer system, a Raman laser system, a cold atom interferometer physical system, and a vibration isolation platform. The laser interferometer system is mounted on the vibration isolation platform, and the cold atom interferometer physical system is positioned above the laser interferometer system with their gravity sensing axes aligned. The Raman laser output from the Raman laser system enters the laser interferometer system as its working light source. This invention utilizes a dual-frequency laser interferometer to directly monitor the vertical displacement of the Raman laser reflector, achieving precise filtering of vibration noise across a wide frequency range, improving the measurement accuracy of the cold atom interferometric gravimeter, reducing accuracy drift, and expanding the applicable frequency range.