Grid-side power factor control method for two-stage matrix converter based on quasi-PR control

Abstract

The invention discloses a grid-side power factor control method for a two-stage matrix converter based on quasi-PR control. The method is characterized by establishing a two-stage matrix converter input-side current mathematical model, proposing a closed-loop control method of a grid-side current tracking a grid-side voltage, normalizing the grid-side voltage and current, using a quasi-PR controller to realize that the normalized value of the grid-side current tracks the normalized value of the grid-side voltage, determining quasi-PR controller parameters based on the root locus theoretical analysis, therefore, ensuring that the system has a large stability margin and steady-state accuracy, and by taking the output of the controller as an input-side current modulation vector of the two-stage matrix converter, realizing the in-phase of the grid-side voltage and the grid-side current. The method of the invention has the beneficial effects of avoiding the rotation coordinate transformation, reducing the calculation amount, and obtaining the same performance as that by PI control; and realizing the adaptive adjustment of the input-side current vector when a system parameter changes, thereby realizing the grid-side unit power factor and having high robustness.

Description

technical field [0001] The invention relates to a dual-stage matrix converter, in particular to a quasi-PR control-based dual-stage matrix converter grid-side power factor control method, which belongs to the field of dual-stage matrix converter control. Background technique [0002] The two-stage matrix converter (Two-Stage Matrix Converter, TSMC) is derived on the basis of the traditional matrix converter (Conventional Matrix Converter, CMC). The DC link in the middle of the traditional AC-DC-AC converter is omitted, so the power density of the converter is improved to a certain extent. In addition, TSMC also has many advantages such as bidirectional energy flow, sinusoidal input current, and controllable input power factor. It has great development potential in many fields such as motor drive, power quality improvement and wind power generation. [0003] Its topology is divided into a rectification stage and an inverter stage. The rectification stage is a current source...

AI Technical Summary

Problems solved by technology

Regardless of which modulation strategy the rectifier stage adopts, the phase of its input current space vector comes from the phase of the grid-side voltage vector. In general, the phase of the grid-side voltage vector is directly used to replace the phase of the input-side current vector of the converter, so as to obtain the phase of the rectifier stage Switching duty cycle, but due to the existence of the input filter and changes in other system parameters, various reasons may cause the phase shift of the grid side current

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