Heuristic variable switching point predictive current control for the three-level neutral point clamped inverter
Stolze, Peter; Karamanakos, Petros; Tomlinson, Males; Kennel, Ralph; Mouton, Toit; Manias, Stefanos (2013-10)
Stolze, Peter
Karamanakos, Petros
Tomlinson, Males
Kennel, Ralph
Mouton, Toit
Manias, Stefanos
IEEE COMPUTER SOCIETY PRESS
10 / 2013
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tuni-202004294342
https://urn.fi/URN:NBN:fi:tuni-202004294342
Kuvaus
Peer reviewed
Tiivistelmä
This paper presents a variable switching point predictive current control (VSP2CC) method for induction machines (IMs) driven by a three-level neutral point clamped (NPC) inverter with a heuristic preselection of the optimal voltage vector. Enumeration-based model predictive control (MPC) methods are very simple, easy to understand and, in general, offer the possibility to control any nonlinear system with arbitrary user-defined terms in the cost function. However, the two most important drawbacks are the increased computational effort which is required and the high ripples on the controlled variables which limit the applicability of these methods. These high ripples result from the fact that in enumeration-based MPC algorithms the actuating variable can only be changed at the beginning of a sampling interval. However, by changing the applied voltage vector within the sampling interval, a voltage vector can be applied for a shorter time than one sample, which results in a reduced ripple. Since this strategy leads to an additional overhead which is crucial especially for multilevel inverters, it is combined with a heuristic preselection of the optimal voltage vector to reduce the calculation effort. Experimental results are provided to verify the proposed strategy. Furthermore, it will be shown experimentally that a conventional enumeration-based MPC method will lead to very low switching frequencies and high current ripples at low machine speeds; this significant drawback can be overcome with the proposed VSP2CC strategy.
Kokoelmat
- TUNICRIS-julkaisut [16944]