S. M. Dehghan, M. Mohamadian, A. Yazdian, A. H. Rajaei, Mr H. Zahedi,
Volume 6, Issue 4 (December 2010)
Abstract
This paper presents a modified nine switch inverter with two inputs and two Z-source networks. This inverter has two DC inputs and two AC outputs. Input DC voltages can be boosted to the required level. Amplitude, frequency and phase of AC output voltages can be controlled, independently. The proposed converter can be used in applications with two unregulated DC sources, which require feeding two independent loads. Compared to the conventional structure, the proposed converter requires reduced number of semiconductor switches hence improved converter reliability and less volume. Performance of the proposed inverter is verified by experimental results.
H. Zahedi Abdolhadi, Gh. Arab Markadeh, S. Taghipour Boroujeni,
Volume 17, Issue 3 (September 2021)
Abstract
Classical structure of Doubly Fed Induction Generators (DFIGs) is not completely adapted in high-speed regions due to their brushes and slip rings. So in the Cascaded DFIGs (CDFIGs), the rotor windings of a given DFIG are supplied by another wound rotor induction machine leading to a complete brushless structure. This paper presents and compares Sliding Mode Control (SMC) and Terminal Sliding Mode Control (TSMC) methods to control the output voltage of CDFIG. The SMC and TSMC methods are identified as strong controllers with large stability and robustness margins. In this paper, the SMC and TSMC methods are evaluated and compared to the conventional Voltage Oriented Control (VOC) in terms of output voltage change, prime over speed’s variation, and nonlinear load. Simulation and experimental results using a TMS320F28335 based prototype system show that the SMC and TSMC techniques are more robust against parameter variations and uncertainties, and TSMC offers improved dynamic response.
