Naslov
Predictive control for multilevel active power filters

Autori
Odavić, Milijana

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, doktorska disertacija

Fakultet
School of Electrical and Electronic Engineering

Mjesto
Nottingham

Datum
16.05

Godina
2008

Stranica
227

Mentor
Mark Sumner

Neposredni voditelj
Pericle Zanchetta

Ključne riječi
digital controllers; predictive control; active shunt filters; multilevel converters; PWM

Sažetak
Active shunt power filters present an effective method to reduce harmonic pollution at the power system level. However, the accurate control of the current in these devices requires a high bandwidth control system which is robust to system parameter changes. This control challenge is amplified when an active shunt filter is employed to deal with harmonic pollution on power networks for More Electric Aircraft (MEA). The fundamental frequency can vary between 360 Hz and 800 Hz and therefore the current controller needs to track (at a minimum) the 5th (4 kHz) and the 7th (5.6 kHz) harmonic components with an 800 Hz supply voltage fundamental component. The precise control of current in active shunt filters is the major focus of this project. The modified predictive current controller proposed in this thesis for the two-level and the five-level shunt active filter control effectively eliminates phase and magnitude errors between the reference and actual current. An analytical identification of the harmonic spectra for both active shunt filter systems considered is derived in this thesis. From this analysis, the five-level shunt active filter is preferred for the MEA application due to its superior harmonic spectrum. For the five-level system, in order to take advantage of all available predicted values within one switching period, the standard modulation technique is modified. The successful reference tracking of the proposed modulation combined with the predictive current control approach implemented in this work is demonstrated through simulation. It is also experimentally verified for current reference frequencies of up to 2.8 kHz (a 7th harmonic component when a fundamental frequency is 400 Hz) with a device switching frequency of up to 5 kHz. These experiments show that the five-level shunt active filter can accurately track high frequency current references with a (relatively) low switching frequency.

Izvorni jezik
Engleski

Znanstvena područja
Elektrotehnika

POVEZANOST RADA