Topology and modulation method of single-phase current-type high-frequency chain-matrix power electronic transformer

Abstract

The invention discloses a single-phase current type high frequency chain matrix power electronic transformer topology and modulation method. The topology includes a sequentially connected power supply network, a front-stage matrix converter, a high-frequency transformer, a post-stage matrix converter, an output filter, and a load, using a high-frequency transformer for magnetic coupling and power transfer, and using a current-mode circuit topology to achieve the output voltage and frequency conversion. In order to make the bidirectional switch of the matrix converter work reasonably, a decoupling and coupling modulation strategy is proposed, which combines the integral unipolar frequency multiplication of the front-stage circuit of the transformer and the discrete type of the rear-stage circuit. The front stage adopts the integral control method to realize the safe commutation of the matrix converter, effectively suppressing the voltage peak caused by the transformer leakage inductance; the latter stage adopts the discrete control method to reduce the number of switching operations and reduce the device The switching loss improves the system efficiency. And a detailed modal analysis is carried out on the modulation principle and the working state of the main circuit.

Description

technical field [0001] The invention relates to the field of power electronic power converter topology and its modulation, in particular to a single-phase current-type high-frequency chain matrix power electronic transformer topology and modulation method. Background technique [0002] In the traditional power grid, the distribution network transformer plays a very important role as a device for voltage level conversion and energy transmission. Traditional power transformers have the advantages of simple structure, high reliability, and low cost. At the same time, traditional power electronic transformers have many disadvantages: large volume, heavy weight, high no-load loss, and environmental pollution caused by the use of insulating oil; traditional distribution network transformers couple AC voltage from the primary side to the secondary side through the iron core and windings. side, in order to realize the transformation of the voltage level. At the same time, the wind...

AI Technical Summary

Problems solved by technology

At the same time, traditional power electronic transformers have many disadvantages: large volume, heavy weight, high no-load loss, and environmental pollution caused by the use of insulating oil; traditional distribution network transformers couple AC voltage from the primary side to the secondary side through the iron core and windings. side, in order to realize the transformation of voltage level

Since the traditional transformer does not have the ability to control the voltage and current, as long as there is any power quality problem on one side of the primary side and the secondary side, it will be transmitted to the other side, affecting the normal operation of the other side; the traditional transformer needs to be equipped with special relay protection device for protection

Images