Three-level Inverter Control Strategy

As a commonly used topology, the diode-clamped three-level inverter are widely used in the high-voltage high-power application field.This inverter has a low voltage requirements and a smaller output voltage harmonic content and become a hot research problem in this field.The three-level inverter has a large number of switching devices, so the control objectives are complicated, three-level inverter control technology has become the core research of the study. This paper studies its control technology in order to serve as a basis for further research.This paper based on carrier modulation method as a basic control, analysis the three-level inverter topology and principle, and also give the simulation; In addition, this article focuses on the three-level space vector modulation, it has a deep study on its modulation algorithm and gives each step of the simulation algorithm; On this basis, for the existence of the neutral-point potential imbalance, this paper studies the causes of the imbalance and the existing control way of contrast, puts forward a new control method and simulation results show the effectiveness of using this method.This article also designed a diode clamped three-level inverter system. the hardware design include the main circuit design, external circuit design and control circuit design, An improvement triangular carrier staked modulation algorithm is validated and designed by the advanced TMS320F2812DSP in the software design. Results show the algorithm is very suitable for the digital software design by the new DSP controller, and the stable control pulses can be obtained.