Publisher : The Korean Institute of Electrical Engineers
DOI : 10.5370/JEET.2015.10.1.280
Title & Authors
Current Decoupling Control for the Three-level PWM Rectifier with a Low Switching Frequency Yuan, Qing-Qing; Xia, Kun;
Three-level PWM rectifiers applied in medium voltage applications usually operate at low switching frequency to keep the dynamic losses under permitted level. However, low switching frequency brings a heavy cross-coupling between the current components and with a poor dynamic system performance and a harmonic distortion in the grid-connecting current. To overcome these problems, a mathematical model based on complex variables of the three-level voltage source PWM rectifier is firstly established, and the reasons of above issues resulted from low switching frequency have been analyzed using modern control theory. Then, a novel control strategy suitable for the current decoupling control based on the complex variables for and is designed here. The comparisons between this kind of control strategy and the normal PI method have been carried out. MATLAB and experimental results are given in detail.
Three-level PWM rectifier;Low switching frequency;Cross-coupling;Complex current controller;
J.A. Pontt et. al., “Network-friendly low-switching frequency multipulse high-power three-level PWM rectifier,” IEEE Transactions on Industrial Electronics, Vol.56, No.4, pp. 1254-1262, April.2009.
H. Akagi et. al., “A new power line conditioner for harmonic compensation in power system,” IEEE Transactions on Power Delivery, Vol.10, No.3, pp.1570-1575, July.1995.
Z. C. Zhang et. al., “Multimodular current-source SPWM converters for superconducting a magnetic energy storage system,” IEEE Transactions on Power Electronics, Vol.8, No.3, pp.250-255, July.1993.
C. Z. Javier et.al., “A large power, low switching frequency voltage source converter for FACTS applications with low effects on the transmission line,” IEEE Transactions on Power Electronics, Vol. 27, No.12, pp.4868-4879, Dec.2012.
L. Cristian et.al., “Frequency response analysis of current controllers for selective harmonic compensation in active power filters,” IEEE Transactions on Industrial Electronics, Vol. 56, No. 2, pp. 337-347, Feb. 2009.
X. Q. Li et. al., “Stability analysis of grid-connected inverters with an LCL filter considering grid impedance,” Journal of Power Electronics, Vol. 13, No. 5, pp. 896-908, Sept.2013.
N. Oikonmou. Control of medium-voltage drives at very low switching frequency, Logos Verlag, 2008.
L.G. Franquelo et.al., “New trends and topologies for high power industrial applications: The multilevel converters solution,” International Conference on Power Engineering, Energy and Electrical Drives, pp.1-6, 2009.
A.G. Siemens. “Power semiconductors: for medium voltage converters-an overview,” 13th European Conference on Power Electronics and Applications, pp.1-14, 2009.
P. B. Rolando et.al., “Complex state variables modeling and nonlinear control of PWM voltage and current source rectifiers,” 28th Annual Conference of the IEEE Industrial Electronics Society, pp.187-192, 2002.
J. Holtz et.al., “Design of fast and robust current regulators for high-power drives based on complex state variables,” IEEE Transactions on Industry Applications, Vol. 40, No. 5, pp. 1388-1397, Sept.-Oct.2004.
J. Holtz et.al., “Estimation of the Fundamental Current in Low-Switching-Frequency High Dynamic Medium-Voltage Drives,” IEEE Transactions on Industry Applications, Vol. 44, No. 5, pp. 1597-1605, Sept. -Oct. 2008.
J. S. Liang et.al., “A three-phase PWM AC-DC converter with low switching frequency and high power factor using DSP-based repetitive control technique,” 29th Annual IEEE Power Electronics Specialists Conferences, pp.517-523, 1998.
S. Kouro et.al., “Model predictive control - a simple and powerful method to control power converters,” IEEE Transactions on Industrial Electronics, Vol. 56, No. 6, pp. 1826-1838, June. 2009.
A. A. Rockhill et.al., “Grid-Filter Design for a Multi-megawatt Medium-Voltage Voltage-Source Inverter,” IEEE Transactions on Industry Applications, Vol. 58, No. 4, pp. 1205-1217, April. 2011.
J. Holtz. “The representation of AC machine dynamics by complex signal flow graphs,” IEEE Transactions on Industrial Electronics, Vol. 42, No. 3, pp.263-271, Jun. 1995.
B. S. Chen, Automation control system for power drives, China Machine Press, chap. 8, 2003.