Integrated gate-commutated thyristor (IGCT)-based hybrid cascaded H-bridge multi-level high-voltage inverter

Abstract

The invention relates to an integrated gate-commutated thyristor (IGCT)-based hybrid cascaded H-bridge multi-level high-voltage inverter, which belongs to the technical field of electric drive. The inverter comprises a rectification unit, a DC unit, an inversion unit and a dv/dt filter, wherein the secondary side of a multi-winding rectifier transformer is connected with the input of the rectification unit; the output of the rectification unit is connected with the input of the DC unit; the output of the DC unit is connected with the inversion unit; and the output of the inversion unit is connected with the dv/dt filter. The inverter solves the problem that 10 kV high-voltage high-capacity output is obtained without realizing direct series connection by IGCT devices, less impacts a power grid in a working process, increases the sine degree of output voltages, has relatively lower difficulties in control and enhanced reliability, improves the working stability of a system, effectively inhibits current harmonics on a power grid side, and makes the distortion rate of line current on an input side meet standard requirements.

Description

technical field [0001] The invention relates to an IGCT-based hybrid series H-bridge multilevel high-voltage frequency converter, which belongs to the technical field of electric drive. Background technique [0002] In today's world, energy has become the pillar of national economic development, and energy conservation and environmental protection have become common concerns of both developed and developing countries. Now there is a requirement to simultaneously develop energy and save energy, and put saving first. Energy saving, in the final analysis, is mainly the saving of electric energy. At present, high-voltage and high-power motor equipment such as medium and high-pressure fans, water pumps, compressors and mixers are widely used in mining, metallurgy, chemical, petroleum, textile and other enterprises, water plants, and power plants, and baffles and valves are often used to adjust flow , or operate at a working condition far below the rated power all the year round,...

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Problems solved by technology

[0008] The present invention is mainly to solve the problems existing in the prior art that each group of inverters of series multiple inverters is connected to a multi-winding phase-shifting transformer to obtain a high-voltage and high-power output of 10kV. Due to the introduction of the output transformer, the inverter The volume and cost are greatly increased and other technical problems; a structure using a multi-winding phase-shifting transformer and six sets of independent rectifiers is provided, which can reduce the harmonic interference of the high-voltage frequency converter to the power grid during the working project and ensure the input current The total harmonic distortion rate THD is less than 5%, which also reduces the size and cost of the inverter. IGCT-based hybrid series H-bridge multi-level high-voltage inverter

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