Showing papers on "Three-phase published in 2016"

Power and Voltage Balance Control of a Novel Three-Phase Solid-State Transformer Using Multilevel Cascaded H-Bridge Inverters for Microgrid Applications

Abstract: This paper presents a new application of power and voltage balance control schemes for the cascaded H-bridge multilevel inverter (CHMI)-based solid-state transformer (SST) topology. To reduce load on the controller and simplify modulation algorithm, a master–slave control (MSC) strategy is designed for the dual active bridge (DAB) stage. The master controller executes all control and modulation calculations, and the slave controllers manage only device switching and protection. Due to the inherent power and dc-link voltage unbalance in cascaded H-bridge-based SST, this paper presents a compensation strategy based on three-phase dq decoupled current controller. An optimum zero-sequence component is injected in the modulation scheme so that the three-phase grid currents are balanced. Furthermore, to tightly regulate the output voltage of all the DAB modules to target value, a dynamic reference voltage method is also implemented. With this proposed control method, the three-phase grid currents and dc-link voltage in each module can be simultaneously balanced. Finally, simulation and experimental results are presented to validate the performance of the controller and its application to microgrid SST.

Leakage Current Elimination of Four-Leg Inverter for Transformerless Three-Phase PV Systems

Abstract: Eliminating the leakage current is one of the most important issues for transformerless three-phase photovoltaic (PV) systems In this paper, the leakage current elimination of a three-phase four-leg PV inverter is investigated With the common-mode loop model established, the generation mechanism of the leakage current is clearly identified Different typical carrier-based modulation methods and their corresponding common-mode voltages are discussed A new modulation strategy with Boolean logic function is proposed to achieve the constant common-mode voltage for the leakage current reduction Finally, the different modulation methods are implemented and tested on the TMS320F28335 DSP +XC3S400 FPGA digital control platform The experimental results verify the effectiveness of the proposed solution

Three-Phase Split-Source Inverter (SSI): Analysis and Modulation

Abstract: In several electrical dc–ac power conversions, the ac output voltage is higher than the input voltage. If a voltage-source inverter (VSI) is used, then an additional dc–dc boosting stage is required to overcome the step-down VSI limitations. Recently, several impedance source converters are gaining higher attentions [1] , [2] , as they are able to provide buck-boost capability in a single conversion stage. This paper proposes the merging of the boost stage and the VSI stage in a single stage dc–ac power conversion, denoted as split-source inverter (SSI). The proposed topology requires the same number of active switches of the VSI, three additional diodes, and the same eight states of a conventional space-vector modulation. It also shows some merits compared to Z-source inverters, especially in terms of reduced switch voltage stress for voltage gains higher than 1.15. This paper presents the analysis of the SSI and compares different modulation schemes. Moreover, it presents a modified modulation scheme to eliminate the low frequency ripple in the input current and the voltage across the inverter bridge. The proposed analysis has been verified by simulation and experimental results on a 2.0-kW prototype.

A Real-Time Multiple Open-Circuit Fault Diagnosis Method in Voltage-Source-Inverter Fed Vector Controlled Drives

Abstract: This paper proposed a fast, real-time and fair robustness scheme for single switch and double switches open-circuit fault diagnosis in pulse-width-modulated voltage source inverter (VSI) for vector-controlled induction motor drives based on three phase output currents, which is also easy to insert into the controlled algorithm as a subroutine without major modification. The concept of allelic points is proposed and corresponding functions are defined to describe the symmetry of the VSI physical topology under healthy and faulty conditions. The residuals between any two phase functions are applied as criterion for allelic points. Under healthy condition, three legs are symmetrical and the residuals are all closed to zero, when open-circuit fault occurs, the residuals will be larger than a predefined threshold, so it is used to detect fault occurrence. When fault occurs, the near-zero current samples per fundamental period will get large, its proportions in a period will be different when different fault classes occur. The fault can be located combined the functions and residuals based on the analysis of VSI topology. The simulations and experiments are carried out and the results show the effectiveness and the merits of the proposed method.

A Linear Power Flow Formulation for Three-Phase Distribution Systems

Abstract: Power flow analysis is one of the tools that is required in most of the distribution system studies. An important characteristic of distribution systems is the load unbalance in the phases and a three-phase power flow analysis is needed. In this paper, a three-phase linear power flow (3LPF) formulation is derived based on the fact that in a typical distribution system, voltage angles and magnitudes vary within relatively narrow boundaries. The accuracy of the proposed 3LPF is verified using several test cases. Potential applications of the proposed method are in distribution systems state estimation and volt-VAR optimization.

Three-Phase LLC Series Resonant DC/DC Converter Using SiC MOSFETs to Realize High-Voltage and High-Frequency Operation

Abstract: SiC MOSFETs are applied to constitute a three-phase, 5-kW LLC series resonant dc/dc converter with isolation transformers. A switching frequency of around 200 kHz for the transistors successfully reduces the volume of these isolation transformers, whereas insulated-gate bipolar transistors (IGBTs) are not capable of achieving such a high switching speed. The high-voltage tolerance of SiC MOSFETs, 1200 V, enables increasing the input voltage up to 600 V. High-voltage tolerance, on the other hand, is not compatible with low on-resistance for Si MOSFETs. A three-phase circuit topology is used to achieve up to 5 kW of power capacity for the converter and reduce per-phase current at the same time. Current-balancing transformers among these three phases effectively suppress a maximum peak current from arising in the circuit, a technique that miniaturizes the input and output capacitances. The conversion efficiency of the converter reaches 97.6% at 5-kW operation.

A New Fault-Tolerant Strategy Based on a Modified Selective Harmonic Technique for Three-Phase Multilevel Converters With a Single Faulty Cell

Abstract: This paper proposes a new fault-tolerant strategy to revamp performance of three-phase multilevel converters with a single faulty switch. The proposed fault-tolerant strategy is based on the application of a modified selective harmonic elimination (SHE) technique in conjunction with the fundamental phase-shift compensation method. The proposed fault-tolerant strategy makes the most use of the converter capacity in the faulty condition, generates balanced line voltages, and eliminates a wide range of lower order harmonics to limit the total harmonic distribution of the converter voltages in the faulty condition. In this paper, first, a brief background about cascaded H-bridge multilevel converters and SHE technique is provided. Then, the proposed fault-tolerant strategy and the modified SHE technique are presented. Finally, several experimental results are provided to validate the operation of the proposed strategy.

Generalized Predictive Current Control (GPCC) for Grid-Tie Three-Phase Inverters

Abstract: This work proposes a linear generalized predictive current control (GPCC) for grid-connected voltage-source inverters, which presents a fast response to current reference step changes, parameter variation robustness, and low distortion at the output currents, with reduced computational effort. Experimental results on a 10-kW converter connected to a real grid are shown, and the proposed controller is compared against a classical proportional resonant controller.

Power-Loss Analysis and Efficiency Maximization of a Silicon-Carbide MOSFET-Based Three-Phase 10-kW Bidirectional EV Charger Using Variable-DC-Bus Control

Abstract: It is expected that wide-bandgap devices like silicon-carbide MOSFETs and gallium-nitride HEMTs could replace Si devices in power electronics converters to reach higher system efficiency. This paper adopts the conventional half-bridge LLC topology to realize a 10-kW all-SiC bidirectional charger used in electric vehicles. Though it is a well-known topology for the unidirectional charger, it has not been comprehensively explored for the bidirectional energy flow yet. A double-pulse-test (DPT) platform is utilized to provide accurate power losses. A state-space model is built to obtain accurate switching current waveforms, which is eventually combined with the DPT results to accurately predict the system efficiency. Based on this model, to further enhance the system efficiency, the dc-bus voltage is varied with LLC dc/dc converter running at the resonant frequency through the whole power range. Experimental results validated that the proposed approach could realize the bidirectional power flow. By varying the dc-bus voltage, the V2G and G2V modes reach $\sim 96$ % wall-to-battery efficiency.

Current Harmonic Compensation in Dual Three-Phase PMSMs Using a Disturbance Observer

Abstract: Dual three-phase electric machines are known to offer many important advantages compared with their conventional three-phase counterparts. However, these machines also suffer from a significant disadvantage of easily occurring large stator current harmonics. To solve this problem, this paper introduces a current harmonic elimination method based on a disturbance observer (DOB). The study provides a detailed analysis and design principles for the DOB. The performance of the proposed method is verified by experimental results. The results show that nearly complete elimination (> 99% reduction) of harmonic components is achieved. In addition, it is shown that the method is robust against uncertainties. The method provides a simple yet effective alternative for solving the issue of stator current harmonics in dual three-phase drives, and the results of this paper can be easily applied also to other multiphase machine types.

Modeling, Modulation, and Control of the Three-Phase Four-Switch PWM Rectifier Under Balanced Voltage

Abstract: The modeling, modulation, and control of the three-phase four-switch (TPFS) PWM rectifier are investigated in this paper. Three space vector pulse width modulation methods using different equivalent zero vectors are developed, where sector identification and the trigonometric function are not required. Then, the high-frequency model for the current ripple analysis is proposed, and the effects of three SVM approaches on the ac current ripple are investigated. According to the analytical results, the method introducing the smallest current ripple is selected. With the optimized SVM approach, a control-oriented model, considering the capacitor voltage oscillation and deviation, is built in the dq synchronous frame to facilitate the controller design. Furthermore, a control strategy implementing the proportional controller is developed to eliminate the capacitor voltage deviation. Meanwhile, the dual-loop control of the TPFS is not affected by the proposed strategy as the capacitor voltage deviation is eliminated. Finally, a novel linear modulation index function is defined to reject the low-frequency harmonic current introduced by the overmodulation. Experimental results demonstrate that excellent current performance is achieved with comprehensive considerations of the modeling, modulation, and control strategy.

A Versatile Unified Power Quality Conditioner Applied to Three-Phase Four-Wire Distribution Systems Using a Dual Control Strategy

Abstract: This paper presents the study, analysis, and practical implementation of a versatile unified power quality conditioner (UPQC), which can be connected in both three-phase three-wire (3P3W) or three-phase four-wire distribution systems for performing the series–parallel power-line conditioning. Thus, even when only a 3P3W power system is available at a plant site, the UPQC is able to carry out power-line compensation for installed loads that require a neutral conductor to operate. Different from the control strategies used in the most of UPQC applications in which the controlled quantities are nonsinusoidal, this UPQC employs a dual compensation strategy such that the controlled quantities are always sinusoidal. Thereby, the series converter is controlled to act as a sinusoidal current source, whereas the parallel converter operates as a sinusoidal voltage source. Thus, because the controlled quantities are sinusoidal, it is possible to reduce the complexity of the algorithms used to calculate the compensation references. Therefore, since the voltage and current controllers are implemented into the synchronous reference frame, their control references are continuous, decreasing the steady-state errors when traditional proportional–integral controllers are employed. Static and dynamic performances, as well as the effectiveness, of the dual UPQC are evaluated by means of experimental results.

Comparison of three-phase three-level voltage source inverter with intermediate dc–dc boost converter and quasi-Z-source inverter

Abstract: This study compares a three-phase three-level voltage source inverter with an intermediate dc–dc boost converter and a quasi-Z-source inverter in terms of passive elements values and dimensions, semiconductor stresses, and overall efficiency. A comparative analysis was conducted with relative parameters to evaluate converter parameters for any application. The equations obtained were confirmed by simulation and experimental setup. Field of application has been discussed.

Three-Phase Bidirectional DC/DC Converter With Six Inverter Legs in Parallel for EV Applications

Abstract: The success of electric vehicles (EVs) greatly depends on battery size, cost, lifetime, and capacity. The battery capacity of EVs has to contain enough energy to allow EV users to drive, at least, the minimum distance that internal combustion engine vehicles take. However, even with very efficient EVs and combining all the available highly efficient EV technologies, the battery capacity still needs to be large. Thus, one alternative to reduce the battery size is to improve the charging infrastructure by implementing sufficient public/private fast-charging locations, which will significantly increase the EV driving range with relatively low battery capacities. However, this kind of infrastructure requires charging with higher current capability, due to the high power levels involved in the fast-charging process. In this paper, a bidirectional dc/dc converter with six inverter legs connected to a three-phase output is proposed. The converter is similar to a three-phase dual-active-bridge (DAB) converter with more inverter legs in parallel. These additional inverter legs increase the converter current capability, without affecting the DAB main characteristics, preserving similar modulation techniques and DAB advantages. An accurate study about the proposed topology is carried out in this paper, and simulations and experimental results are shown for a 20-kW prototype, validating the theoretical analysis.

Comparative Study of the Three-Phase Grid-Connected Inverter Sharing Unbalanced Three-Phase and/or Single-Phase systems

Abstract: Unbalance in a three-phase system is created due to single-phase loads and distributed single-phase renewable energy sources connected to the same system. This unbalance can be compensated locally at the point of common coupling using a three-phase four-wire grid-tied inverter. This paper presents a comparative study of three-phase four-wire inverter topologies to compensate for positive, negative, and zero sequence components of the current injected into the grid. The function of the inverter is to inject power to the grid and additional active power compensation (APC) to support unbalance, load reactive power, and load neutral current. Performance analysis and control of these topologies are being compared to evaluate utilization of dc link, size, control, and ease of implementation. A quantitative comparison of the topologies is provided to illustrate the advantages and disadvantages of the analyzed systems. The control algorithm has been presented to regulate the active and reactive power in each phase independently during both grid-connected and islanded modes. The analysis of three-phase 480-V 50-kV·A system based on three H-bridge converter is presented with simulation and experimental results. The experimental results validate the ability of the inverter to provide four-quadrant control of each phase independently.

Single-Stage Three-Phase Differential-Mode Buck-Boost Inverters With Continuous Input Current for PV Applications

Abstract: Differential-mode buck-boost inverters have merits such as reduced switch number, ability to provide voltages higher or lower than the input voltage magnitude, improved efficiency, reduced cost and size, and increased power density, especially in low-power applications. There are five buck-boost inverters that can provide flexible output voltage without the need of a large electrolytic input side capacitor, which degrades the reliability of inverters. The continuous input current of these inverters is appropriate for maximum power point tracking operation in photovoltaic and fuel cells applications. Three of the five inverters can be isolated with high-frequency-link transformers where the common-mode leakage current can be mitigated. However, the performance and control of such converters have not been discussed in detail. In this paper, the five possible single-stage three-phase differential-mode buck-boost inverters with continuous input current are investigated and compared in terms of total losses, maximum ripple current, total harmonic distortion, and device and passive element ratings. In addition, the possible methods are presented for eliminating the input third-order harmonic current, resulting from the stored energy in the passive elements, as well as the output second-order harmonic currents. The ability for isolating the input and output sides of the inverters with a small–high frequency transformers is discussed. A changeable-terminal 2.5-kW bidirectional inverter is used to validate the design flexibility of the inverter topologies, when digital signal processor-controlled.

Photovoltaic systems in low-voltage networks and overvoltage correction with reactive power control

Abstract: This study deals with the overvoltage problems caused by the increased photovoltaic (PV) penetration in typical rural radial distribution systems, where small PV systems and household consumers are connected. For this study, the authors used an iterative algorithm to solve the power flow problem in radial grids and considered three methods for the correction of unacceptable overvoltages, which are based on different principles. The system under consideration is an almost symmetrical three phase, low-voltage radial network, consisting of nine PV and consumer connection points. The system was simulated for a whole year with a sample time of 15 min, taking into account the variations of the solar radiation and loads. The results verified that the control of reactive power on the line can successfully manage overvoltage issues. The additional demand of reactive power and consequent line losses are used to evaluate various correction methods.

Single-Stage Three-Phase AC–AC Matrix Converter for Inductive Power Transfer Systems

Abstract: A direct three-phase ac–ac matrix converter for inductive power transfer (IPT) systems with soft-switching operation is introduced. The proposed topology is expected to have a high reliability and extended lifetime due to the soft-switching operation and elimination of short-life electrolytic capacitors. The soft-switching operation will also reduce switching stress, switching loss, and electromagnetic interference of the converter. A variable-frequency control strategy based on the energy-injection and free-oscillation technique is used to regulate the resonant current, the resonant voltage, and the output power. With the use of reverse-blocking switches, the proposed converter can be built with a reduced number of switches (only seven), which will consequently increase the reliability and efficiency and reduce the cost of the converter. The converter operates in eight modes, which are described in detail. With the use of the proposed converter as the primary converter, simulation analysis and experimental implementations on a case study IPT system show that the current regulation control method can fully regulate the output current and output power around user-defined reference values, thus making it suitable for dynamic IPT applications, where the system has inherent variations.

An Integrated Inductor for Parallel Interleaved Three-Phase Voltage Source Converters

Abstract: Three-phase voltage source converters (VSCs) are often connected in parallel to realize the high current output converter system. The harmonic quality of the resultant switched output voltage can be improved by interleaving the carrier signals of these parallel-connected VSCs. As a result, the line current filtering requirement can be reduced. However, an additional inductive filter is required to suppress the circulating current. The integrated inductive component, which combines the functionality of the line filter inductor and the circulating current inductor is presented in this paper. An analysis of the flux density distribution in the integrated inductor is presented and design procedure is described. The analysis has been also verified by performing finite-element analysis. The advantage offered by the use of the integrated inductor is demonstrated by comparing its volume with the volume of the state-of-the-art filtering solution. The performance of the integrated inductor is also verified by the experimental measurements.

Comparative Experimental Investigation of Broken Bar Fault Detectability in Induction Motors

Abstract: It has been shown in the past that the zero-sequence current spectrum can be reliably used to detect broken bar faults in induction motors. Previous work was carried out with extensive FEM analysis. Although it allows detailed study of spatial and time-dependent electromagnetic characteristics of induction motors, FEM is a heavily time-consuming tool and this limits full study. So, in this work, extensive experimental testing has been performed to validate the zero sequence current spectrum for detecting rotor asymmetries. Three identical induction motors have been used: one healthy, one with a broken rotor bar, and one with two broken rotor bars. The motors were tested under different voltage supply levels and with different mechanical loads. The zero-sequence current spectrum was calculated after measuring the three phase currents. It is for the first time experimentally shown that this approach offers greater diagnostic potential than traditional MCSA.

Optimized Common-Mode Voltage Reduction PWM for Three-Phase Voltage-Source Inverters

Abstract: In this paper, two new optimized common-mode voltage reduction PWM (CMVRPWM) strategies based on solving the established constrained nonlinear programming models in the time domain are proposed and analyzed. The proposed current ripple losses-optimized CMVRPWM (CRLO-CMVRPWM) minimizes the mean-square values of the three-phase current ripples by calculating the optimized special solutions of the voltage–second balance equations under the designed switching sequences. CRLO-CMVRPWM can achieve better output waveform quality than the existing methods. The proposed switching losses-optimized CMVRPWM (SLO-CMVRPWM) online optimizes the bus-clamping styles according to the phase currents to minimize the switching losses under different load power factors. Compared to the near-state PWM with fixed bus-clamping styles, SLO-CMVRPWM can reduce more switching losses in broader range of the modulation index. Simulation and experimental results verify the superiority of the proposed strategies to the conventional ones.

A Multipulse Pattern Modulation Scheme for Harmonic Mitigation in Three-Phase Multimotor Drives

Abstract: A continuous improvement of power electronics technology has widely increased the applications of adjustable speed motor drives in many areas. Beyond the control flexibility, the power electronics devices (e.g., diode rectifiers) are also the main harmonic source to the grid due to their nonlinearity, which thus deteriorates the power grid quality and also lowers the conversion efficiency. Both degradations are apt to occur in motor drive applications. At present, many industrial drives are equipped with three-phase diode rectifiers and employ passive filtering techniques on the ac or the dc side of the rectifier. In such topologies, it is difficult to implement the prior-art harmonic control strategies. Moreover, the total cost and complexity has become the main obstacle for these harmonic elimination approaches in multiple drive systems. Therefore, in this paper, a new cost-effective harmonic mitigation approach has been proposed for multiple drives. The proposed approach can control the generated current harmonics by benefiting of the nonlinearity of the drive units and through a novel current modulation scheme. The obtained results at the simulation and the experimental level validate the effectiveness of the proposed approach.

H8 Inverter for Common-Mode Voltage Reduction in Electric Drives

Abstract: This paper presents a modified two-level three-phase inverter for the reduction of the leakage current. With respect to a traditional two-level inverter, the proposed solution reduces the common-mode voltage (CMV), both in amplitude and frequency. Between the dc source and the traditional three-phase bridge, two active dc-decoupling devices and a voltage-clamping network have been added. A dedicated control strategy was developed adopting a modified space vector pulse-width modulation, oriented to the reduction of the CMV. Simulations showing the good performance of the solution are presented. A preliminary prototype was developed and experimental results are presented.

Vector selection approach-based hexagonal hysteresis space vector current controller for a three phase diode clamped MLI with capacitor voltage balancing

Abstract: The purpose of this study is to provide a broad idea about current control scheme and equilibrating voltages in DC-link capacitors of the neutral-point clamped multilevel inverter (NPC-MLI), using an innovative hexagonal space vector hysteresis current control (SVHCC) scheme. The main ideology is to force the literal current vector to reach the reference current vector through an appropriate voltage vector selection sequence. This proposed scheme defines two hexagonal hysteresis bands encompassing the error vector, as a first step. With respect to the error vector location, the selection of the adjacent vector is acted to minimise the error vector. In addition to the error vector selection, the capacitor voltage is also equilibrated by controlling the degree of freedom available in selecting the switching vectors. The SVHCC scheme is intelligent in performing modulation depth dependent selection of switching vectors between the groups namely closest three vector and preferred three vector (PTV). This scheme balances the DC-link capacitors’ voltages within a tolerance limit for any value of modulation index. The proposed scheme is asserted through MATLAB/Simulink software. The superiority of the proposed technique is validated through the 2 kW NPC-MLI supported with SPARTAN III 3AN –XC3S400 field programmable gate array.

A New SVPWM for the Phase Current Reconstruction of Three-Phase Three-level T-type Converters

Abstract: This paper presents a new space vector pulsewidth modulation scheme to reconstruct phase currents using neutral-point current sensing in three-level T-type converters (TLTTCs). For this purpose, zero vector and offset vectors are replaced with complementary active vectors. These active vectors do not affect the resultant output voltage and the voltage balance at the neutral point of TLTTCs. Hence, the pulsewidths of corresponding active vectors can be adjusted even at low speeds without much additional switching losses and low-frequency noise in the inverter. The modified switching patterns can easily be generated without significant computational complexity. The proposed method is experimentally verified using Texas Instruments TMS320F28335 and Spartan 6 controllers, on a custom designed T-type converter based on Fuji IGBT modules.

Model-Based Control for a Three-Phase Shunt Active Power Filter

Abstract: This paper presents a robust model-based control in natural frame for a three-phase shunt active power filter. For the proposed control method, a linear converter model is deduced. Then, this model is used in a Kalman filter (KF) to estimate the system state-space variables. Even though the states estimation do not match the variables of the real system, it has allowed to design three sliding-mode controllers providing the following features to the closed-loop system: 1) robustness due to the fact that control specifications are met independently of any variation in the system parameters; 2) noise immunity, since a KF is applied; 3) a lower total harmonic distortion (THD) of the current delivered by the grid compared with the standard solution using measured variables; 4) the fundamental component of the voltage at the point of common coupling is estimated even in the case of a distorted grid; and 5) a reduction in the number of sensors. Thanks to this solution, the sliding surfaces for each controller are independent. This decoupling property of the three controllers allows using a fixed switching-frequency algorithm that ensures a perfect current control. Finally, experimental results validate the proposed control strategy and illustrate all its interesting features.

A Fault-Tolerant Strategy Based on Fundamental Phase-Shift Compensation for Three-Phase Multilevel Converters With Quasi-Z-Source Networks With Discontinuous Input Current

Abstract: This paper proposes a new fault-tolerant strategy for a multilevel converter with an integrated impedance-source network. The proposed fault-tolerant strategy leverages the flexibility provided by the impedance-source network to implement the fundamental phase-shift compensation (FPSC) method in order to restore operation of a multilevel converter with one or more faulty switches to the prefault conditions. In case of a fault occurrence, the proposed fault-tolerant strategy makes the most use of the remaining converter capacity and generates balanced line-to-line voltages, while evenly distributing an inevitable voltage stress increase, over all converter switches. In this paper, first, a brief background about an impedance-source based cascaded H-bridge converter and a suitable modulation method for it is provided. Then, the FPSC method is explained and the proposed fault-tolerant strategy based on this method is introduced. Finally, several experimental results from a prototype converter are provided to validate the operation of the proposed strategy.

PUC5 inverter - a promising topology for single-phase and three-phase applications

Abstract: The newly emerged packed U-cell (PUC5) inverter topology is investigated in this paper considering the design criteria, switching technique, voltage balancing of DC capacitor and switches voltages ratings. Afterwards, It is compared with other popular multilevel inverter topologies such as 3-level full-bridge (FB), 5-level cascaded H-bridge (CHB), neutral point clamped (NPC) and T3, in terms of components count, voltage balancing complexity, voltage rating, switching frequency, etc. in continue, the 3-phase configuration of the PUC5 inverter is presented and its proper application would be discussed. Some experimental results are shown to accredit the performance of the 3-phase PUC5 inverter in 3-wire and 4-wire systems to supply 1-phase and 3-phase AC loads.