Your Digital Power Electronics Processor Choice power electronics processor is crucial to success in Digital Power. And the key to choosing in a way that doesn’t end up creating delays in the project delivery.
So what are the most important issues to consider
Delays in the digital processor add phase lag and so can make getting stable operation at reasonable target bandwidth. Estimating accurately the delay that is acceptable and possible with possible target processors ensures that the processor will not run out of time during the development.
How to manage the limited number of bits
The limited number of bits in a processor means that there is a trade off between precision and dynamic range. The natural instinct is often to have larger dynamic range and lower precision. Best practice is to choose the opposite. Joins us in the webinar to see why.
Likewise timer precision limits the available resolution in PWM and variable frequency modulators.
ELMG Digital Power are offering you the opportunity to attend our regular webinar on Digital Power Electronics. The next webinar is
Tuesday June 4 at 12 noon PDT (3pm EDT)
This is an hour webinar on that details the accumulated ELMG Digital Power experience with processor choices for power electronics control
Join ELMG Digital Power’s regular monthly Digital Power Webinar and expand your Digital Power knowledge and expertise.
The webinar will be hosted and presented by Dr. Hamish Laird ELMG Digital Power’s CTO Hamish has 25 years experience the design and implementation of varied digital control systems and IP for power electronics.
This exciting opportunity is free and includes a 15 minute Q&A session with Dr. Hamish.
An example given in the “2. Timer Precision” section of the document reads:
‘Consider the case where the timer clock runs at 40MHz. If the variable period oscillator register has 256 bits then the maximum frequency that the VPO can make is 10MHz and the minimum is 39.0625kHz. The example LLC resonant power converter needs a variable frequency of 500kHz to 210kHz to perform the control. This means the VPO count register has a usable range from 80 to 191. This is 111 counts which is 6.8 equivalent bits or almost seven bits.”
Equivalent bits are a great way to look at numeric precision.
For your Digital Control Workshop which microcontrollers are taught in the class?
The uniqueness of the Digital Control Workshop is that it is not focused on one microcontroller family. We cover the key know how that ensures you and your team will get your digital power supply robust and reliable.
Here at ELMG Digital Power our platform is an FPGA based power converter controller that we have developed. We sell power electronic specific FPGA IP blocks for PWM, filters, three to two blocks and all the other required power electronic blocks.
We have development experience in using processors for power electronics control from
Our course came about when and R and D manager asked us why his team had knowledge gaps that we were now helping fix. These gaps were common across a number of our OEM clients. We address these key common knowledge gaps in the course.
Happy to have a netmeeting or skype call to talk through this at anytime.
This post was originally published in 2010. It is republished here because it looks like people are still doing the inductor-go-round.
So what is the inductor-go-round? It is like a merry-go-round (carousel) except with inductors. It can cost companies (or their startup backers) lots of time and money. And usually when you are on the inductor-go-round it feels much like a carousel at a fair. Round and round and sadly, not much progress.
Often the optimization of a power converter’s performance comes down to the optimization of the converter inductor. (It can also be optimization of the transformer but lets for the moment assume a non-isolated converter). For people with big and small inductors there is, it seems, an inductor go round.
What is a big inductor? At ELMG Electronics Design and Development we generally say that any inductor with mass more than 1 kg – and yes it says kilograms (1kg = 2.2 pounds) – is a big inductor. Some of you will say that until you have a 40kg inductor you don’t really have an inductor. Other inductors will be smaller. I guess it is all a matter of what you are familiar with.
For the inductors for grid connected inverters people start with laminated iron or some other laminated material. This is typically the inexpensive choice. Some others choose ferrite cores. Some start with another core material.
Air cored next
Then running first into core material problems they then move to air cored as the core is the cause of all the problems. They then either come up against either;
the magnetic field interference problem (the enclosure is now the core),
the fault rupture problems that occur with designing air cored mechanical restraints,
or the size constraint.
From here most people head to a modern core material such a powder core. These materials are not necessarily homogeneous and so they then realize that to get long life times requires careful consideration of the wear out mechanisms and to meet this requirement means using a quality core material vendor (See www.micrometals.com/thermalaging_index.html for a good first discussion on thermal aging). The lesson here is that not all core materials are the same.
At this point some people go back to iron or ferrite and others go to an alternative core material like an amorphous alloy. If they then cannot meet the price point then they may well go back to laminated iron.
At this stage the realization is that there is no magic answer. The optimization of power inductors becomes the requirement and there is usually a realization that the inductor vendors are not as able as they seem. In the defense of the inductor manufacturers it must be said that most power electronics companies struggle to correctly specify inductors.
Getting off the inductor go round means designing the inductor completely.