Rapid overmodulation method and system for 3D-SVPWM modulation strategy

Abstract

The invention discloses a rapid overmodulation method and system for a 3D-SVPWM modulation strategy, belongs to the technical field of inverter modulation, and solves the problem of how to calculate the maximum linear modulation degree of the 3D-SVPWM modulation strategy and improve the modulation range of the 3D-SVPWM modulation strategy through an overmodulation technology while the 3D-SVPWM modulation strategy is not changed and the characteristics of a differential mode component and a common mode component are modulated at the same time. The maximum linear modulation degree of the 3D-SVPWM modulation strategy is obtained through calculation, a spatial modulation body where a spatial modulation reference vector is located is judged, and a corresponding compression plane constraint equation and a rapid compression scheme constraint equation are combined during overmodulation. On the premise that the 3D-SVPWM modulation strategy is not changed and the characteristics of a differential mode component and a common mode component are modulated at the same time, through the overmodulation technology, the modulation range of the 3D-SVPWM modulation strategy is improved, the operand is reduced, the execution time of the algorithm is shortened, overmodulation is rapidly realized, the modulation range of the 3D-SVPWM modulation strategy is widened, and the applicability of the 3D-SVPWM modulation strategy is effectively enhanced.

Description

technical field [0001] The invention belongs to the technical field of inverter modulation, and relates to a fast overmodulation method and system of a 3D-SVPWM modulation strategy. Background technique [0002] The 3D-SVPWM modulation (three-dimensional space vector pulse width modulation) strategy can simultaneously modulate the differential mode component and the common mode component of the reference voltage vector, so it is widely used in zero-sequence circulating current control that needs to modulate the common mode voltage, such as common DC Busbar and common neutral double inverter open winding topology, three-phase four-leg inverter, etc. Compared with the traditional SVPWM modulation strategy that only focuses on differential mode component modulation, the 3D-SVPWM modulation strategy has a limited output range of differential mode component modulation due to simultaneous modulation of common mode components. Therefore, it is urgent to calculate the relevant linea...

AI Technical Summary

Problems solved by technology

[0004] To sum up, the existing technology has the following problems: 1) For the 3D-SVPWM modulation strategy, the prior art only provides the basic synthesis principle and implementation process, and does not give the linear modulation range of the 3D-SVPWM modulation strategy, that is, the maximum Linear modulation degree; 2) There is no constraint scheme for the overmodulation of the 3D-SVPWM modulation strategy, so the overmodulation constraint scheme cannot be used to effectively expand the scope of application of the 3D-SVPWM modulation strategy

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