The goal of this paper is to model, compare and analyze the performance of multiple photovoltaic (PV) array configurations under various partial shading and faulty PV conditions. For this purpose, a multiple PV array configurations including series (S), parallel (P), series-parallel (SP), total-cross-tied (TCT) and bridge-linked (BL) are carried out under several partial shading conditions such as, increase or decrease in the partial shading on a row of PV modules and increase or decrease in the partial shading on a column of PV modules. Additionally, in order to test the performance of each PV configuration under faulty PV conditions, from 1 to 6 Faulty PV modules have been disconnected in each PV array configuration. Several indicators such as short circuit current (I sc ), current at maximum power point (I mpp ), open circuit voltage (V oc ), voltage at maximum power point (V mpp ), series resistance (R s ), fill factor (FF) and thermal voltage (V te ) have been used to compare the obtained results from each partial shading and PV faulty condition applied to the PV system. MATLAB/Simulink software is used to perform the simulation and the analysis for each examined PV array configuration.

Abstract-The paper describes a new application of flying capacitor multi-level inverters whereby a three-phase, four-leg three-level inverter is used for harmonic current cancellation and unbalanced current compensation in a 4-wire system. A direct 3D-PWM scheme is developed to deal with the increased state redundancy in the four-leg flying capacitor multilevel inverter. Test results show much superior performance in the four-leg case, which may allow the use of smaller DC supply capacitors. A new modified dead-beat current control algorithm is proposed and combined successfully with the 3D-PWM modulation technique in a hardware demonstrator of a complete active filter.

Module-integrated PV and converter units have been a promising technique for achieving maximum power generation for mismatching and/or partially shaded PV modules. Control of a PV system with multiple such units is difficult as the operation of each unit is required to be regulated to generate the maximum power according to its respective light level. This paper presents a novel model-based, two-loop control scheme for a particular MIPC system, where bidirectional Ćuk dc-dc converters are used as the bypass converters and a terminal Ćuk boost functioning as a whole system power conditioner. Experimental tests of example systems consisting of two and three serially connected units are presented showing that the proposed system can increase power generation as much as 30%, compared to the conventional bypass diode structure. In general with n modules in series the maximum power gain is expected to be (100/n) %. The new control scheme is developed using analytical expressions for the transfer functions of the power converters. The control results showing rapid and stable responses are superior to that obtained by bypass diode structure which is conventionally controlled using Perturbation-and-Observation method.

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This paper presents a new application of modular multilevel cascaded converters (MMCC) for combined active harmonic current elimination and reactive power compensation in a power distribution line. A technique for simultaneous extracting harmonic components and reactive element in the load current is presented. A novel voltage control scheme for balancing the module intra-cluster capacitor voltages under distorted load current is incorporated. Simulation studies show the desired performance of the MMCC-based active power conditioning operating under PCC current distortion and varying load conditions.