Power Electronics Converter Topologies
Stacked Multi-Cell (SMC)

Multilevel converters have emerged in recent years as a very important alternative in the area of high-power medium-voltage energy control. The need for an increase in the power level of industrial applications is especially important in high power applications such as high power AC motor drives, active power filters, and renewable energies.

The term multilevel refers to the three-level topologies and above. The increase in the number of levels in the converter leads to harmonic distortion. Yet, as the number of levels increases so does the control complexity.

The most common multilevel topologies include the Neutral Point Clamped (NPC) converter (in its 3-Level version), the T-Type, the Active Neutral-Point Clamped (in its 3-Level and Multi-Level versions) the Multicell topologies such as the Flying Capacitor (FC), the Stacked Multi-cell Converter (SMC).

Electrical schema

power converter topologies 5-level stacked multi-cell smc

Example of a 5-level Stacked Multi-Cell (SMC)

Conversion stage

  • DC/DC mono and bi-directional

  • DC/AC mono and bi-directional

Number of levels

  • Typical: 5
  • Max: 9

Intellectual Property

Initial Patent FR2809548

Notes

  • It needs much fewer capacitors than an equivalent flying capacitor.

Typical application and trends

  • Medium voltage drive up to 13.8kVAC
  • Medium voltage Solar up to 1500VDC

Advantages

  • Modular
  • Efficient use of powerswitches
  • High power
  • High number of levels
  • High voltage

Drawbacks

  • Need flying capacitor

Fill in the form to download the PDF