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In this paper, a new and efficient global optimization method known as teaching-learning-based optimization is adopted to optimally design the parameters of a passive RC-damped LCL filter for grid-connected voltage source inverters. The novel proposed objective function of the optimization algorithm is to minimize the values of inductors and capacitors. The proposed design improves inverter efficiency and minimizes filter stored energy at a predefined operating and switching frequencies. Moreover, the proposed design procedure may reduce the complexity of the passive RC-damped LCL filter by removing one inductor or one capacitor. The optimal design procedure is built based on an accurate mathematical model and description of the filter topology. A detailed comparison between the results of the proposed work and related work in the literature is thoroughly discussed. The optimized filter is designed, built, and validated analytically and experimentally for verification based on a hardware prototype. [ABSTRACT FROM AUTHOR]

Enhancing the performance of the voltage source inverters (VSIs) without changing the hardware structure has recently acquired an increased amount of interest. In this study, an optimization algorithm, enhancing the quality of the output power and the efficiency of three-phase grid connected VSIs is proposed. Towards that end, the proposed algorithm varies the switching frequency (fsw) to maintain the best balance between switching losses of the insulated-gate-bipolar-transistor (IGBT) power module as well as the output power quality under all loading conditions, including the ambient temperature effect. Since there is a contradiction with these two measures in relation to the switching frequency, the theory of multi-objective optimization is employed. The proposed algorithm is executed on the platform of Altera® DE2-115 field-programmable-gate-array (FPGA) in which the optimal value of the switching frequency is determined online without the need for heavy offline calculations and/or lookup tables. With adopting the proposed algorithm, there is an improvement in the VSI efficiency without degrading the output power quality. Therefore, the proposed algorithm enhances the lifetime of the IGBT power module because of reduced variations in the module’s junction temperature. An experimental prototype is built, and experimental tests are conducted for the verification of the viability of the proposed algorithm. [ABSTRACT FROM AUTHOR]

This paper presents the mathematical and harmonic analyses of output phase voltages of three-phase voltage source inverters which employ a hybrid two-dimensional–threedimensional (2-D–3-D) space vector modulation (SVM) voltage control algorithm. The explicit time-domain representation of the harmonic components in addition to the total harmonic distortion (THD) of the output phase voltages is given in terms of system and control parameters. This paper also investigates the harmonic characteristics and THD performance against the linearity of the modulation region which helps in the harmonic performance and design studies of such inverters employing the hybrid 2-D–3-D SVM. The fundamental component of the output voltages follows the reference with lower THD in the linear modulation region rather than the overmodulation region. Experimental results are used to validate these analyses as well as the effectiveness of the hybrid 2-D–3-D SVM algorithm for generating balanced and low THD phase voltages. [ABSTRACT FROM PUBLISHER]