Performance Analysis of a Three-to-Five Phase Dual Matrix Converter Based on Space Vector Pulse Width Modulation

The equivalence of space vector pulse width modulation (PWM) and carrier-based PWM through the injection of a common-mode voltage is already known for two-level (first min-max injection) and multilevel (double min-max injection) three-phase converters. However, under regular sampled phase voltage references, these injections do not produce the lowest total harmonic distortion (THD) of the load phase current throughout the linear modulation index range. This paper proposes the use of a similar common-mode injection, called the second min-max injection that achieves the lowest current THD in regions of the modulation index range where the double min-max injection fails to do so. A cascaded H-bridge (CHB) topology is analyzed, and comparison is made between different multicarrier modulation strategies, using simulation results, under different injections for the whole modulation index range. The level-shifted in-phase disposition modulation method is found to produce the lowest load phase current THD with second min-max offset voltage injection for modulation indices below unity. For modulation indices greater than one, the double min-max injection is still considered as optimal.

This paper introduces an integrated energy storage and reactive power compensation in a large wind power plant, and it deals to regulate the reactive power supplied by a variable-speed Wind Energy Conversion System (WECS), based on an induction generator fed by a Matrix Converter (MC). The control strategy used in this paper is input current observer, implemented using an estimation of the modulation index, and a nonlinear control loop that regulates the displacement angle at the matrix converter input. This paper is described the implemention of the matrix converter to control the reactive power by using the Space Vector Pulse Width Modulation (SVPWM) technique in large wind farms and combining them into one system to maintain stability control of the wind power plant. Control of reactive power increases the regulating capacity, which can provide voltage stability in the wind farm. In this work, Matlab/Simulink TM model and simulation of the three phase matrix converter have been performed using the space vector control algorithm. The algorithm uses a simpler method than the other control algorithms to control the input power factor. To verify the performance of the proposed Matrix Converter, modulation strategy, and control design methodology, various simulation results are presented.

SVPWM control strategy for a three phase five level dual inverter fed open-end winding induction motor

This article proposes an optimized space vector pulsewidth modulation (SVPWM) strategy with minimum common-mode voltage (CMV). Compared with earlier SVPWM methods, the proposed optimized strategy is implemented in the 45 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> coordinates. Locating the sector triangle, calculating the duty cycles, and determining the switching sequences require only basic arithmetic operations, which greatly reduces the computational complexity. The switching state with minimum CMV corresponding to the space vector can be calculated directly. The proposed optimized modulation strategy effectively solves the problem that the traditional SVPWM is difficult to be implemented as the number of levels increases. It can be easily extended to any level converters without additional computational burden. Based on the proposed optimized SVPWM strategy with minimum CMV, the SVPWM strategy for eliminating CMV is proposed. The proposed SVPWM strategy for eliminating CMV improves the utilization of the redundant cells and reduces the total harmonic distortion of phase voltages without increasing the difficulty of implementing the SVPWM algorithm. Finally, the proposed two SVPWM strategies are verified with extensive simulations and experiments.

This paper aims at obtaining fixed output voltage of frequency 50 Hz to the load by a Self Excited Induction Generator (SEIG) employed in Wind Energy Conversion System (WECS). The output voltage of a SEIG is a function of wind turbine’s speed, which varies with wind velocity. Due to the variation in shaft speed of the wind turbine, the output voltage and frequency of Doubly Fed Induction Generator (DFIG) will vary. In this paper, a new WECS is proposed in which the conventional PWM AC/ DC/ AC converter is replaced by a Matrix Converter (MC) topology and the DFIG machine is replaced by a low cost Squirrel Cage Induction Generator. MC eliminates bulky DC link capacitor, provides bi-directional power flow capability, independent control on the output voltage magnitude, frequency and phase angle as well as the input power factor. Space Vector Pulse Width Modulation (SVPWM) technique is used for controlling MC in such a way that output load voltage and frequency is kept constant for all wind velocities. The SVPWM technique provides higher voltage transfer ratio without lower order harmonics. SVPWM is digitally implemented using DSP processor (TMS320 F2407A). Switching times are pre-calculated offline. Semi soft commutation procedure for safe switching control of MC switches is also presented.

This paper presents a unified carrier-based modulation method for direct matrix converter. Various types of pulse width modulation (PWM) methods are generated by using the offset voltage, changing slope of carrier waveform, and adjusting the free parameters in the modulation algorithm. The proposed method is equivalent to the space vector pulse width modulation (SVPWM) for two-level and three-level voltage source inverter (VSI). This paper also presents a new viewpoint to understand the matrix converter modulation method such as single carrier based modulation technique for two-level VSI and double carrier based modulation technique for three-level VSI. Using the proposed method, this paper presents discontinuous pulse width modulation (DPWM) for the matrix converter. Therefore, a unified simple algorithm suitable for the digital implementation of all continuous and discontinuous PWM strategies is proposed. The feasibility of the proposed modulation method has been verified by a computer simulation results. These results show that the proposed carrier-based modulation method can be implemented easily without any tables.

Multilevel inverters are increasingly being used in high-power medium voltage industrial drive applications due to their superior performance compared to conventional two-level inverters. Thre are a number of Pulse width modulation (PWM) techniques applied in recent years. The most widely applied PWM techniques are Sine Pulse Width Modulation (SPWM) and Space Vector Pulse Width Modulation (SVPWM). SPWM is the most simple modulation technique that can realize easily in analog circuit. However, it has some drawbacks such as higher total harmonic distortion (THD), lower effective DC utilization and lower switching frequency. Space vector pulse width modulation (SVPWM) is widely used because of their easier digital realization and better DC bus utilization and lower THD. The complexity is due to the difficulty in determining the reference vector location, on times calculation, and switching states selection. This paper presents a simple SVPWM algorithm for diode clamped three level inverters based on standard two-level SVPWM which can easily determine the location of reference vector, calculate the on-times, the selection of switching states. Three level diode clamped inverter (3LDCI) using space vector modulation technique has been modeled and simulated using MATLAB/SIMULINK and Origin 6.1 with a passive R-L load that can be extended to any level. Simulation results are presented to verify the proposed SVPWM control in terms of THD. The results are compared with conventional sinusoidal pulse width modulation (SPWM) where SVPWM shows better performance than SPWM in terms of THD. DOI: http://dx.doi.org/10.11591/ijpeds.v5i1.6038

The impact of common mode voltage (CMV) on induction motor life is significant under non‐sinusoidal terminal voltage. In the advent of matrix converters for multi‐phase drives pose a challenge not only to reduce CMV but also to maintain the load current total harmonic distortion (THD) within the acceptable limits. Hence, the matrix converter (MC) performance is attributed to CMV reduction, load current THD minimization and supply side UPF maintenance which together is difficult to attend without any trade‐off. This paper presents a three‐phase to six‐phase matrix converter ( MC) with virtual vector‐based predictive control. In the classical predictive control selective utilization of the available voltage vectors, could lead to CMV reduction at the cost of the increase in the load current THD. The proposed predictive control is derived with selective virtual voltage vector formation to reduce the CMV while maintaining the load current THD within the limits. The trade‐off between CMV and THD is achieved by using a decisive weighting factor in the cost function. The performance of the MC, such as efficiency improvement with supply side unity power factor (UPF) is also achieved. This control algorithm is executed using a low‐cost dsPIC processor and verified experimentally to validate the effectiveness of the proposed algorithm.

The Variable Frequency Drives (VFD) are a common type of controlling the speed of 3-phase induction motors which are based on two control modulation techniques of Voltage Source Inverter: Sinusoidal Pulse Width Modulation (SPWM) and Space Vector Pulse Width Modulation (SV-PWM). The SPWM control technique is known as an easier implementation, but the SV-PWM control technique can be distinguished by an easier digital realization and a better utilization of DC bus. All 3-phase PWM inverters produce a total harmonic distortion (THD) on its output, which causes electromechanical and thermal stresses. The aim of this paper is comparing the low order current harmonics while driving an unbalanced 3-phase induction motor (the case of deterioration of the insulation as a result of inter-turn short circuits between few turns of the same phase) using SPWM and SV-PWM two-level 3-phase Voltage Source Inverters (VSI). For this type of unbalanced 3-phase induction motor, the SVPWM and SV-PWM schemes are modeled and simulated using Matlab/Simulink software. A detailed comparative analysis of THD-phase currents is made for both modulation strategies at different switching frequencies while keeping the constant amplitude modulation index.

The Multilevel inverter topologies (MLIs) are increasingly being used, which is the preferred choice in many industrial Medium-voltage (MV) applications. The inherent low switching frequency in medium voltage neutral point clamped MLI (NPC-MLI) fed industrial drives represent the power quality issues and filter-design challenges. In this paper, two multilevel pulse width modulation (PWM) methods; multi-carrier sine PWM (MCSPWM) and space vector PWM (SVPWM) has been considered for NPC-MLI. Both the methods are compared and analyzed based on different constraints such as voltage profile, total harmonic distortion (THD), common mode voltage (CMV) and neutral point fluctuation (NPF). The results convey that the SVPWM method is superior when compared with the MCSPWM algorithms. Analytical and simulation results achieved by using the MATLAB/Simulink for control systems are experimentally verified using FPGA-SPARTAN – III generation – 3AN –XC3S400 with a 2KW NPC-MLI fed adjustable speed – drive system.

Due to its advantages, the asymmetrical dual three-phase induction motor drive is a strong choice in high-power applications. However, the common-mode voltage produced by the voltage source inverters affects the winding insulation and damages the bearings. Common-mode voltage is also responsible for electromagnetic interference and leakage currents. This paper, therefore, analyses the common-mode voltage produced by the inverter supplying a dual three-phase induction motor drive and proposes a novel modified space vector decomposition-based Space Vector Pulse Width Modulation (SVPWM) technique for common mode reduction. The vector space decomposition-based space vector modulation technique offers excellent flexibility as it reduces the common-mode voltage (CMV) by exploiting the additional degree of freedom in a dual three-phase system. The common-mode voltage (CMV) can be reduced to one-sixth of the DC link voltage compared to the highest CMV, i.e. half of the DC-link voltage produced in conventional space vector modulation. The proposed method is also validated experimentally to demonstrate the effectiveness of the proposed scheme in terms of the amplitude of CMV, pulsations, and total harmonic distortion(THD) in current.

This study presents a space vector pulse width modulation (PWM) method for a multilevel single-phase decentralized power converter (DPC) called MSPDPC. The proposed model is built by connecting half-bridge cells in series. The output voltage can be adjusted according to demand by adding or subtracting cells. Cells use communication protocols to transmit and receive information with two neighboring cells. The received data contains information for the decentralized space vector pulse width modulation (DSVPWM) method proposed in this paper. In the proposed DSVPWM method, cells set up links to exchange information such as cell position, total cells in a phase, reference voltage amplitude, and reference frequency. The PWM control signals of each cell are calculated based on the information received. The study also focuses on evaluating the ability to adjust the switching vector and the corresponding dwell time of the cells when the structure of the DPC changes. The ability to dynamically reconfigure the DPC is a crucial feature that ensures uninterrupted power supply in case of one or several cell failures. The system automatically establishes a new state with the active cells. The proposed configuration and communication method between cells provide very fast configuration times. The load voltage of the DPC is adjusted to 0.5 times the voltage per cell, which allows the modulation voltage amplitude to be adjusted best according to the load requirements. The study used Matlab/Simulink software to review the initial assessments. The proposed model and algorithms will be verified on the Digital Signal Processor (DSP) platform with a 220V/500W load.

This paper proposes the space vector pulse width modulation technique of a matrix converter topology with three phase fixed grid input and seven phase variable voltage variable frequency output. Voltage source inverter is generally used for feeding multi-phase drives. Multi-phase matrix converter is proposed in this paper as a new solution for feeding multi phase system. The paper develops the complete space vector algorithm of the proposed multi-phase matrix converter topology. The developed space vector model suggests 221 possible switching combination vectors. After imposing mathematical constraints the number of switching combinations reduce to 2184 active and three zero vectors. The complete space vector PWM algorithm is developed in the paper. The feasibility of the proposed algorithm is proved using analytical, simulation and real-time approach.

The inverters and control methods are applied in more and more fields with power electronics development. The technology of current hysteretic band PWM is a kind of easy and reliable control method. But the harmonic distortion of load current is big amplitude around switching frequency side band. The paper introduce a Varied Hysteretic-band Current control technique(VHBCC), this method can spreads the spectrum contents of load current around switching frequency side band, reduces the harmonic distortion of load current . At last, The results of simulation prove the method feasible and effective.

A voltage source inverter with variable frequency and variable voltage is applied for three-phase interior permanent magnet synchronous motor (IPMSM) drive for variable speed application. To obtain the required output voltage in the line side of the inverter a suitable pulse width modulation technique is used. The most prominent PWM techniques are Sinusoidal pulse width modulation (SPWM) and Space vector pulse width modulation (SVPWM). SPWM is simple and easy method to generate pulses for inverter, whereas SVPWM is an accurate method and generate less harmonic distortion compared to SPWM. However there is a lot of complexity involved in calculation of angle and sector as the level increases with SVPWM. To overcome this a similar and easy method known as unified pulse with modulation also know as carrier based space vector pulse width modulation technique(CBSVPWM is described using the concept of effective time. By using this method the inverter output voltage is directly synthesized by the effective times and the voltage modulation task can be greatly simplified. In this paper an IPMSM drive using CBSVPWM is simulated using MATLAB/SIMULINK software and its performance is compared with SPWM by varying modulation index (MI). The simulation study reveals that CBSVPWM simple and easy method which utilizes dc bus voltage more effectively and generates less THD compared to SPWM.