A svpwm control method, system and device for eliminating dead zone effect

Abstract

The present application discloses a SVPWM control method, system and device for eliminating the dead zone effect, which are applied to NPC multilevel converters, including: obtaining three sub-vectors for synthesizing the target voltage vector, and determining the three sub-vectors The action time ratio and its corresponding switch state, and then according to the action time ratio and switch state, the initial comparison value of each phase in the three phases is obtained; according to the current direction of each phase in the three phases and the slope of the triangular carrier, use the preset Correction amount, correcting the initial comparison value to obtain the correction comparison value; comparing the correction comparison value of each of the three phases with the triangular carrier wave to obtain the corresponding comparison result; according to the comparison result of each phase, the phase is logically processed , to generate SVPWM pulses. The SVPWM pulse obtained by the invention can obtain a relatively ideal sine wave output voltage, the total harmonic distortion of the output current is obviously reduced, and the impact on the load or the power supply network is avoided.

Description

technical field [0001] The invention relates to the field of power electronics and electric transmission, in particular to a SVPWM control method, system and device for eliminating the dead zone effect. Background technique [0002] The diode-clamped (Neutral Point Clamped, NPC) three-level topology is very suitable for medium-voltage and high-power industrial converter drives, such as electric locomotive traction, offshore wind power, metallurgical rolling mills, mine hoists, ship propellers, etc., combined with Existing commercial high-voltage and high-power semiconductor devices (such as IGBT, IGCT, TEGT, etc.) can realize the high withstand voltage and strong overcurrent performance of the converter. Space Vector Pulse Width Modulation (Space Vector PWM, SVPWM) has been widely researched and applied in medium-voltage and high-power conversion applications due to its advantages of high DC voltage utilization and good performance in a wide range of modulation ratios. [0...

AI Technical Summary

Problems solved by technology

Due to the existence of the dead zone, the switching device cannot switch in an ideal way, so that the output voltage deviates, resulting in output voltage distortion, and the harmonic content of the output voltage and current is more, causing an impact on the load or power supply network, such as causing the torque of the motor to occur Severe fluctuations or even damage, Total Harmonic Distortion (THD, Total Harmonic Distortion) of the output current does not meet international or domestic grid-connected standards, etc., and the impact of wide dead zone is even worse

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