Double in series high voltage frequency conversion device

Abstract

The invention relates to a high-voltage frequency conversion device, comprising a control drive circuit, an input unit group, an output unit group, a coupling unit group positioned between an input unit and an output unit. Each coupling unit is composed of a three-phase pulse transformer or three single-phase pulse transformers, and output coils of the pulse transformers respectively correspond to one phase of the output of the device. Each input unit in the input unit group comprises a capacitance for supporting a unit voltage, an electronic power element which forms a three phase inverter bridge, and a current-limiting resistance connected with a protection switch in a parallel way; one input unit corresponds to one or a plurality of output units. Each output unit comprises a high-frequency rectification circuit and the capacitance, the polarity of the high-frequency rectification circuit can be controlled, the high-frequency rectification circuit is connected with the pulse transformer output end of a coupling unit, and all the output units are in series connected to form a three-phase output. The array sequences of the input units and the corresponding input unit space are accordant. The invention realizes the input-output double series through an electronic power device, and an input transformer is reformed, so as to lead the unit power cost of a high-voltage transducer to be close to that of a general low-voltage transducer.

Description

Technical field [0001] The invention relates to a high-voltage frequency conversion device for realizing frequency conversion and speed regulation of medium and high-voltage AC motors. Background technique [0002] As we all know, in production practice, where the frequency of the AC power supply is higher or lower than the grid frequency, or where the frequency is required to be adjustable, the inverter must be used. In industry, AC motors are used to achieve power transmission ratios. DC motors are simpler in structure, easier to manufacture, cheaper, and more convenient to maintain. Therefore, AC motors of various capacities have been widely used. Most of these machines use constant-speed AC transmission, and the output adjustment is carried out by means of baffles, valves or air discharge return, which loses a lot of electric energy in vain. Therefore, the use of frequency conversion speed regulation on this type of machinery, and the use of electrical means to change the out...

AI Technical Summary

Problems solved by technology

However, due to the rising prices of raw materials such as copper and iron, and the rising cost of environmental protection, the cost of transformers with iron cores, coils and insulating materials as the main components continues to increase, resulting in increasingly high prices for high-voltage inverters.

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