Digital Control & Analog Control for DC-DC converter

[drewcrew]

Hello,

I'm having a hard time getting a quality description about the differences between analog control and digital control for DC-DC converters. I know the Digital control is now the new way to go as far as control and its ease of implementation with microcontrollers. Can someone please give me quality reasons as to why the digital control approach is better than the conventional analog control.

Thanks

 

[emontllo]

Some ideas that came to my mind:
Flexibility of control without the need of changing PCB components.
Control loop performance (only limited by processor capabilities).
"Intelligent" current, voltage and temperature protections.
Possibility to implement algorithms to reduce EMI emissions with frequency jittering or non-fixed frequency switching.
User interface or interface for regulation and monitoring.
Possibility to coordinate various converters for paralleling or series connection.
And others...

 

[mtwieg]

Actually for DC-DC converters, programmable digital controllers (like MCUs, DSPs, FPGAs, etc) are still uncommon in most applications. You'll find them more often in DC-AC converters (VFDs, GTIs, etc), since generating a sine wave is trickier in analog than generating DC. For DC-DC, you'll probably only find MCUs in high end, high power converters. For simple applications you're likely to find a specialized analog controller IC which performs all the desired features, at lower cost and complexity.

However, recently there has been a trend in controllers to integrating more digital functions, and lots of "programmable controllers" are starting to emerge. They offer a lot of the flexibility of a fully programmable solution, but with less complexity (no ADCs or DACs or digital filters to program).

 

[AMSA84]

I agree with mtwieg. Taking into account what emontllo said, I would add the fact that with digital controllers there is less sensitivity to electronic components variations due to several factor (temperature, admissible tolerances of the components, etc).

I am starting to get more interested on digital control and specially applied to DC-DC / DC-AC converters. (z-transform, bilinear transformation, and so on).

By the way, can someone tell me any good article, paper, thesis or book about digital control and/or digital control for DC-DC/AC control.