A Step Forward for Benchmark and Design Tools for Power Electronics


Guillaume Fontes, PHD at Power Design Technologies SA
Aurélie Cretté, MS at Power Design Technologies SA

The power converter multi-objective optimization design challenge

To develop the next generation of power converters, tools should help designers overcome design and test challenges that can win in the market. Designers have to choose between a series of different components, topologies, control laws. They especially have to understand the performance specifications and reliability of power semiconductor devices since their performance strongly dictates the efficiency and reliability of the entire power converter circuit. This is critical for the success of a design that fulfils and will soon need to exceed the expected performance and the specifications. Besides, the characteristics of the electrical equipment (lower mass, volume, cost and higher efficiency and reliability) must be significantly improved.

As these converters manage energy flows, looking for the maximum efficiency leads to design conversion systems with minimal power density: i.e. conversion systems whose size tends towards infinity. Thus, designers have to find solutions with the best compromise between efficiency and compactness (mass, volume) of the power converters. Other trends or challenges can be considered such as failure rate, cost, etc as noted in [1].

 

Figure 1: Performance trends & challenges [1]

 

Current design tools are not up to challenge 

Today, generic or very specific analysis software is available for power electronic designers, but they only answer partially or locally to their needs. Few software tools in the domain of power electronics can assist them in the “operational” steps of conception such as design or optimization. The need for new tools has been clearly stated several times [1, 2]. And the first need is surely a tool which: 

  • allows the engineer to quickly benchmark power switches (including WBG devices [3] ) and thus with sensitive analysis of some parameters such as the switching frequency, 
  • provides “interfacing” features to feed into the next stage of the design process such model exports to standard circuit simulation tools.

 

Tools need to jump over a major hurdle

Powerswitch manufacturer’s supplied datasheet information is often not homogeneous enough to easily meet these challenges: the datasheet conditions can be quite different from actual use conditions, and the supplied information often has large margins with little information on device variations. This makes it hard to evaluate the performances of different power switches and to compare them. This is even truer for WBG devices since manufacturers differ on what specifications need to be on the datasheet and which ones they do not include.

 

How do tools address the need to benchmark power switches & topologies?

Some semiconductor manufacturers propose different applications (essentially web applications these recent years) to evaluate the losses of their switches (ABB, Wolfspeed, Infineon, Dynex…) and more and more often for different topologies which helps a bit the engineer to evaluate power switch losses in an early-stage design phase.

Yet, at least two improvements are necessary to bring real help to engineer in this step:

  • manage power switch references of different manufacturers in the same tool,
  • provide an automated sweep of some parameters and especially the switching frequency.

 

So, is there no critical need? Or no will to address it?

Existing manufacturer-owned solutions confirm that the need has been identified. At Power Design Technologies, we believe that only a third-party can make a difference for the designers. That’s why we have developed PowerForge, an innovative software which can easily allow the engineer to benchmark different power switch references and different topologies (including multilevel topologies) and now with an automated sweep of the switching frequency. 

 

Why an automated sweep of the switching frequency?

Once the engineer has set voltage and current levels, chosen a topology, the switching frequency is one of the first (or the first?) parameters he would like to evaluate to see the influence on the losses, the volume and the mass of the whole converter.

The figure below plots efficiency vs specific power from a frequency of 2 kHz to a frequency of 16 kHz. It clearly shows an optimal switching frequency range in terms of mass/efficiency tradeoff.

Indeed, when the switching frequency starts to increase from 2 kHz to 8 kHz, the specific power increases because the size of the filters is reduced. But the efficiency also increases because of the decrease of filter loss (mainly because the inductor is reduced) compensates the loss increase in the switching cell. After 10 kHz, the loss reduction in the filters is not enough to compensate for the loss increase in the switching cell and that is why the whole efficiency decreases.

 

Figure 2: Result outputs of an automated sweep of the switching frequency displayed in PowerForge

 

Performing a manual sweep i.e. every single manual calculation for a switching frequency range is highly tedious and time-consuming. It is what we, at Power Design Technologies consider a waste of time and energy of expert teams. We thus have developed PowerForge software focusing on these key dimensions: speed, stability, and efficiency. We reduce the time-consuming steps, display critical key performance indicators in a user-friendly interface and offer the designers the possibility to explore the results they need to access. The future exploration of a new area of opportunities including those offered by wide band gap components is PowerForge.

 

Cut time & costs: design in a click and benchmark all your power converters’ performances.

How?

  • ONE ARCHITECTURE
  • ONE SWITCHING FREQUENCY RANGE
  • ONE CLICK
  • ALL THE DESIGN OPTIONS AVAILABLE

PowerForge‘s newest feature the automated sweep of the switching frequency was released this summer. Engineers can now generate all the designs for a given architecture for a switching frequency range with a single click and within a few seconds.

 

Figure 3: Workflow process in PowerForge

 

Designers select a topology, type the boundaries of the frequency range to be explored, enter the sweeping interval and launch the creation of the designs.

For each design created, all the key data needed to benchmark the performances of multiple options and choose the optimal power converter design solution: mass, volume, loss, cost, specific power… are calculated and displayed in a user-friendly interface.

 

Explore and benchmark power converters using PowerForge!

Visit our website: www.powerdesign.tech!

 

Power Design Technologies will be present at EPE 2019 in Genoa! Let’s meet there!

Join us at Booth #27 for an exclusive presentation of PowerForge

Find out more about PowerForge on Wednesday the 4th at 4.00PM
[1] Drofenik, U., Cottet, D., Müsing, A., & Kolar, J. W. (2007). Design tools for power electronics: trends and innovations. Ingenieurs de l‘automobile, 791, 55-62.
[2] Kolar, J.W. (2014). What are the “Big CHALLENGES” in Power Electronic?. CIPS.
[3] Design and Simulation of Power Electronics with EDA Tools

Part I: https://literature.cdn.keysight.com/litweb/pdf/5992-1166EN. pdf?id=2699182

Part II: https://literature.cdn.keysight.com/litweb/pdf/5992-1167EN. pdf?id=2699184
 

About the Author/s:

Guillaume Fontes

Guillaume Fontes is an experienced Chief Scientific Officer with a demonstrated history of working in the computer software industry for Electrical Engineering at Power Design Technologies SA. He has two post-doctoral researcher degree from Institut Néel CNRS and Centre National d'Études Spatiales.

Aurélie Cretté

Aurélie Cretté is the Head of the Marketing at Power Desgin Technologies SA.He is a former Market Research Manager for a multinational FMCG Company. He has a MS in Management of Climate Change & Sustainable Development.

More information: Power Design Technologies  •  Power Design Technologies SA    Source: Bodo's Power Systems, September 2019