View source for Engineering:Predictive control of switching power converters

{{Short description|Feedback control system}}
'''Predictive controllers''' rely on [[Optimal control|optimum control systems]] theory and aim to solve a [[Loss function|cost function]] minimization problem.<ref>Levine, W. S. ed. The Control Handbook, CRC/IEEE Press, Boca Raton, USA, 1996.</ref><ref>M. Athans, Lecture Notes on Design of Robust Multivariable Feedback Control System, Prof. of Electrical Engineering, MIT, Visiting Research Emeritus Prof ISR/IST, Lisboa, 2004</ref>  Predictive controllers are relatively easy to numerically implement but [[Engineering:Electronics|electronic]] [[Engineering:Power converter|power converter]]s are non-linear time-varying dynamic systems, so a different approach to predictive must be taken.

==Principles of non-linear predictive optimum control==
The first step to designing a predictive controller is to derive a detailed direct [[Mathematical model|dynamic model]] (including non-linearities) of the switching [[Engineering:Power converter|power converter]]. This model must contain enough detail of the converter dynamics to allow, from initial conditions, a forecast in [[Real-time computing|real time]] and with negligible error, of the future behavior of the converter.

Sliding mode control of switching power converters chooses a [[Vector space|vector]] to reach sliding mode as fast as possible (high switching [[Physics:Frequency|frequency]]).

It would be better to choose a vector to ensure zero error at the end of the sampling period Δt.To find such a vector, a previous calculation can be made (prediction);

The converter has a finite number of vectors (states) and is usually non-linear: one way is to try all vectors to find the one that minimizes the control errors, prior to the application of that vector to the converter.

* Direct dynamics model-based predictive control (DDMBPC)

[[File: DD predictive flowchart.JPG|thumb|Direct Dynamics Predictive Control of Switching Power Converters]]

* Inverse dynamics optimum predictive control (IDOPC)

[[File: ID predictive flowchart.JPG|thumb|Inverse Dynamics Predictive Control of Switching Power Converters]]

== References ==
<references />

[[Category:Power electronics]]
[[Category:Electric power conversion]]

{{Sourceattribution|Predictive control of switching power converters}}