SPWM Control Research Articles

Pulse Width Modulation Inverter Control Methods-A Comprehensive Study

Harmonics in electrical supply refers to the distortion of the normal electrical waveform due to the presence of frequencies that are multiples of the fundamental frequency. The presence of harmonics in electrical supply can lead to a number of problems, including: Overheating of equipment, Power quality issues, Extra energy consumption etc. This research aims to provide a cost-effective solution to reduce harmonics in three phase inverters and improve power factor without using any hardware components such as filters and multi-level inverters and by simply changing control pulses of the inverter switches. This research provides a comparison of three most popular inverter control techniques SPWM control, THPWM control and SVPWM control techniques of three phase inverters. All these techniques were compared with the help of MATLAB-SIMULINK and the best control technique with lower order harmonics and less power factor was determined.

The current status and development of DC/AC inverter technology

The advantages, applications, and development trends of DC/AC inverter technology are compared with conventional inverter technology. The traditional DC/AC inverter technology of the low-frequency link inverter process has been gradually replaced by the high-frequency band inverter process. The replacement of the industrial frequency transformer in the low-frequency link inverter process technology with a high-frequency transformer further optimizes and improves the low-frequency link inverter process technology and significantly enhances the characteristics of the inverter. In this paper, some new inverters are highlighted. The focus is on a new high-frequency chain inverter using a unipolar SPWM control method to design different drive logic control switch tubes. A single-stage single-phase high-to-low voltage converter is widely used to interchange solar and wind turbine power supplies. They all belong to PV inverters with high reliability and a wide input voltage range. These completely solve the problems of large size, high ratio, and poor dynamic response of low-frequency transformers. Future trends in inverters at this stage are mainly characterized by high frequency, high performance, and high input power factor.

Research on Simulation System of Microgrids based on STM32

With the gradual depletion of traditional fossil energy and the increasing demand for electricity, finding new energy sources has become the only way for sustainable development. Microgrid is becoming an important auxiliary power for some developed and developing countries to solve the supply problem of energy system, which can not only effectively improve the overall utilization rate of renewable energy, but also improve the power supply reliability of the main grid. In this paper, the hardware circuit and software control of microgrid simulation system based on STM32 are studied and designed. The main circuit design of microgrid simulation system is based on STM32 single chip microcomputer as the main control core, and the pulse modulation signal SPWM is output through the software program of STM32F103CBT6 single chip microcomputer. The MOS driving circuit provides driving voltage and control signal to drive the inverter bridge to invert DC into AC. The inverter bridge is modulated by SPWM control technology, and the high-frequency signal in AC is filtered by low-pass filtering circuit, and finally the stable AC with a fixed frequency of 50 Hz is the output. By calculating the device parameters of the main control circuit and the full-bridge inverter circuit in the hardware unit circuit, and making appropriate selection of components, the specific model is determined, and finally the circuit design of the whole circuit is completed. The hardware circuit is designed rationally by Altium designer, and the software circuit is programmed by Keil. The influence of SPWM signal output by the circuit on the resistance load and its output waveform is analyzed comprehensively, and the influence of working frequency on the output waveform of the circuit is studied.

A kind of full-bridge buck type multi-input inverter with high-frequency Link

A kind of full-bridge Buck type multi-input inverter (MII) with high-frequency link is put forward in this paper, and the pivotal issues such as control policy, transfer modes of power, steady characteristics and improved feedback path of reactive energy are deeply studied, and some crucial verdicts are acquired. The suggested topology consists of a simultaneous selection power switching circuit with output in series, a full-bridge inverter, a transformer with high-frequency link, a cycloconverter and LC filter cascaded in order. The energy management control strategy (EMCS) of presented multi-input inverter adopts the progressive technology of unipolar phase-shifting SPWM control and master-slave energy distribution, which can realize the stable operation of the inverter and the smooth transformation of each power delivery mode under the abrupt change of load or multiple input sources. A 1kVA prototype of proposed multi-input inverter is developed and tested. The results of experiment demonstrate that the presented multi-input inverter possesses the superior characteristics of high stability, low output waveform THD and fast response.

Single-Phase ZVS Quasi-Z-Source Inverter With High Voltage Gain

A single-phase zero-voltage switching (ZVS) quasi-Z-source inverter with a high voltage gain is proposed, and important conclusions are obtained through the in-depth analysis of the key technologies, such as the topology, control strategy, high-frequency switching process, voltage transfer ratio, resonant processes, and ZVS condition, and the design criteria of key parameters. The inverter is composed of an impedance network with a high voltage gain, a ZVS auxiliary network, a single-phase inverter bridge, and an output <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> filter, adopting the unipolar SPWM control strategy with instantaneous feedback of output voltage and energy storage capacitor voltage. The impedance network is comprised of an energy storage inductor and two same diode–inductor–capacitor–capacitor cells; the ZVS auxiliary network includes a resonant inductor, a clamping capacitor, and an auxiliary switch, which provides the ZVS condition for power switches. The experimental results of a 1-kVA prototype verify that the proposed inverter features a high voltage gain, ZVS of all switches, high conversion efficiency, high output power quality, and strong load adaptability and has an important prospect in single-phase inversion with low input voltage or wide input voltage range.

Improving Power Density of a Three-Level ANPC Structure Using the Electro-Thermal Model of Inverter and a Modified SPWM Technique

Multilevel inverter structures have become an interesting substitute for the well-known two-level inverters in a variety of applications due to their exceptional characteristics when compared to conventional inverters. One major issue regarding multilevel structures is the unequal junction temperature of the switches which deteriorates the power density and increase the cost of the inverter by reducing the maximum achievable output power with a given thermal model and cooling system. Hence, on account of the aggressive goals of power density and cost in a majority of power electronic applications, this article proposes a new technique for reducing the maximum junction temperature of switches in a three-level active neutral-point clamped (ANPC) inverter based on a junction temperature estimation method and a modified SPWM control scheme. This technique can ensure up to a 12% rise in the power density value when compared to basic SPWM techniques with no loss distribution algorithm. Moreover, the suggested approach can be used as a protection stage in the inverter which protects the inverter in transient loads, while allowing for reaching the maximum power capability of the inverter. Finally, the simulations of the proposed technique are validated with experimental results of a 400 V, 20 kW three-level ANPC inverter, controlled by the conventional and proposed techniques.

A type of piecewise and modular energy storage topology achieved by dual carrier cross phase shift SPWM control

This paper proposes a novel type of piecewise and modular energy storage topology. Compared to the modular multilevel converter (MMC), the proposed topology is not only different in structure but also in concept. Firstly, the capacitors within the submodules of MMC are all replaced by lithium batteries, which can avoid the voltage imbalance among capacitors and provide a deep connection between MMC and energy storage. What's more, the micro-unit concept is adopted to break the whole batteries within MMC into parts for each submodule by increasing the number of submodules to an extremely high level, which turns it into a novel microelement-based energy storage device. Due to the characteristics of the proposed topology, dual carrier cross-phase shift sinusoidal pulse width modulation (DCCPS-SPWM) is also proposed. With the help of DCCPS-SPWM, the proposed topology has the advantages of simple structure, easy to control, fewer total modules with the same output level, high fault tolerance, easy to detect and locate faults. The operating modes with four energy storage units per bridge arm are well analysed and extended to the case of N units. The double-Fourier analysis is performed on the output voltage waveform, so that the harmonics of the output voltage with DCCPS-SPWM can be clearly understood. Finally, the feasibility of the proposed topology and its control are verified by both simulation and experimental results.

Research on balance control strategy of single capacitor clamped five‐level inverter clamping capacitor

A five-level inverter composed of a single capacitor clamped three-level topology and a half-bridge is introduced, and a new SPWM control strategy for this topology is proposed. The strategy uses two modulation waves with opposite directions to modulate the positive and negative half-cycle interleaved carriers. By controlling the charging and discharging times of the clamping capacitor in each carrier cycle, the voltage balance control of the clamping capacitor is achieved. At the same time, a single-phase capacitor clamped five-level inverter is taken as an example to analyse the principle of the capacitor balance control strategy in detail, and to verify the correctness and feasibility of the control strategy through simulation research and experimental results.

A Study on the Core Loss of SPWM Inverter Drive IPMSM considering High Frequency Harmonics

In the paper, the core loss of SPWM inverter drive IPMSM is analyzed considering high frequency harmonics caused by SPWM and field weakening control. The output current of SPWM inverter has many high frequency harmonics at the field weakening region. The high frequency harmonics would affect the core loss on each part such as the yoke, teeth, shoe, and rotor. Therefore, IPMSM core of double layer type is divided into 6 parts to analyze the core loss in each part. In order to calculate the core loss considering the harmonics, the SPWM current is required. This is extracted by linking the SPWM inverter drive IPMSM. FEM analysis is used to compare the core loss when sinusoidal current and SPWM current are applied. The result that which part of the core is most affected is analyzed by FFT analysis applying the P.U. system.

Digital control strategy for SPWM MPPT of PV system with three-phase NPC three-level converter

&lt;p&gt;&lt;span&gt;This paper is aimed at investigating MPPT of PV system controlled by SPWM which is generated by comparing sinusoidal wave with variable frequency sawtooth wave. Perturb and Observe (P&amp;amp;O) method is used for MPPT control of PV system. NPC three-phase three-level converter with LCL filter is designed to produce output voltage with minimum Total Harmonic Distortion (THD) and high efficiency. The simple and fast method to get MPP of PV system with variable irradiation is digital control where the maximum power point is obtained from look-up table for the values of optimum voltage that achieve the maximum power for each irradiance value is used for digital control signal in microcontroller. The output voltage harmonic of multi-level three-phase inverter is controlled using SPWM control. THD of output voltage of multi-level three-phase inverter is 22% of stand-alone and grid-connected PV system. Small rate LCL filter is used to limit voltage harmonics within medium and low voltage limits (5%). THD output voltage of LCL filter is 4.9% and 3.51% of stand-alone and grid-connected PV system respectively. &lt;/span&gt;&lt;/p&gt;

Research on the Three- phase Cascaded Dual-buck Grid-connected Inverter

The inhibition of common-mode leakage current is the key problem to be solved in cascaded photovoltaic grid-connected inverter. To eliminate the common-mode leakage current of cascaded dual-buck grid-connected inverter, a three-phase cascade double-buck photovoltaic grid-connected inverter (TPCDBGCI) topology is proposed in this paper. Meanwhile, a new phase-shifting carrier SPWM (PSCSWPM) control strategy that can make the single phase common-mode voltage and three phase differential-mode voltage constant in the half cycle is presented. Then, the simplified model and operating modes of TPCDBGCI are analyzed, which show that common-mode leakage current of TPCDBGCI is effectively suppressed. Finally, the experimental results verified the correctness of TPCDBGCI.

Sinusoidal Pulse Width Modulation Based Speed Control of Induction Motor using Fifteen Level Diode Clamped Multilevel Inverter

The main purpose of this work is to use a fifteen-stage diode clamped multi-level inverter that is able to control the speed of an induction motor. To get reduced synchronization and high quality sine curve output voltage. The proposed plan for the diode clamped multilevel inverter is controlled using multicarrier SPWM control. An open circle speed control can be accomplished by utilizing the V/ƒ strategy. This strategy can be executed by changing the recurrence utilized in the three-stage induction motor at the stock voltage and the consistent rate. The proposed system, which results in a poor driver performance, is a useful alternative to the conventional method with high transient losses. Simulation depicts an improved drive performance by reducing the Total Harmonic Distortion resulting from the simulation and effectively controlling the motor speed.

Transmission system regularization with 5-level cascaded IPFC

&lt;p class="JESAbstract"&gt;In recent years, there is an immensely huge demand to power due to industrialization and modernization, butcorrespondingly the amplification of generation and transmission has not been done due to constrained resources and environmental limitations. The huge growth in demand leads to various problems in power systems. Heavy growth in semiconductor technology made power electronics plays a key role in solving these problems. Flexible AC transmission system (FACTS) devices are used for fixing various problems in power system. They are used for enhancing the existing transmission capabilities and improving the system dynamic performance so that to make transmission system flexible and efficient in operation. Inter line power flow controller (IPFC) is a latest generation series connected FACTS device, having capability of controlling power flow among multi line in a transmission network. In this paper cascaded 5 level inverter is used as the inverter module for IPFC. Control techniques play a vital role in power flow control in the system, with the main objective of minimization of harmonics and obtaining a variable output with maximum fundamental component. This paper discusses various comparative case studies on IPFC with cascaded 5 level inverter using SPWM and SVM control techniques.&lt;/p&gt;

Validation of Control Platform Using TMS320F28027F for Dynamic Voltage Restorer to Improve Power Quality

A real-time control platform progressed for the power quality (PQ) change in a conveyance framework has been displayed in this paper. A DSP-based control platform is demonstrated for voltage sag compensation for dynamic voltage restorer in conjunction with a voltage source inverter (VSI) to enhance PQ. The output of VSI is controlled by activating IGBTs by SPWM control technique. A driver circuit is developed along with a filter circuit to compensate load voltage when sag occurs in a distribution system supplying a sensitive load of single-phase induction motor. The developed control platform has been asserted with a DSP processor TMS320F28027F, and its effectiveness has been shown by carrying a few experiments.

A Bridge Modular Switched-Capacitor-Based Multilevel Inverter With Optimized SPWM Control Method and Enhanced Power-Decoupling Ability

Microinverters operating into the single-phase grid from new energy source with low-voltage output face the challenges of efficiency bottleneck and twice-line-frequency variation. This paper proposed a multilevel inverter based on bridge modular switched-capacitor (BMSC) circuits with its superiority in conversion efficiency and power density. The topology is composed of dc–dc and dc–ac stages with independent control for each stage, aiming to improve system stability and simplify the control method. The BMSC dc–dc stage, which can be expanded to synthesize more levels, not only features multilevel voltage gain but also partially replaces the original bulk input capacitor and functions as an active energy buffer to enhance power-decoupling ability between dc and ac sides. In dc–ac stage, the control strategy of optimized unipolar frequency doubling sine-wave pulse width modulation is proposed to improve the quality of output waveform. Meanwhile, the multilevel voltage phase has been optimized to further reduce the power loss. Finally, a prototype has been built and tested. Associated with the simulation, the experimental results validate the practicability of these analyses.

A Cascaded NPC/H- Bridge Inverter with Superior Harmonic Content and Improved DC Link Voltage Control for Grid Interface Application

Modeling of Cascaded Multilevel converter has put more emphasize on conventional cascaded H- bridge inverter. First a new phase shifted SPWM control algorithm for cascaded NPC/H-bridge inverter is proposed. Its Superior harmonic suppression is verified by comparing its harmonic spectrum with that of the conventional multicarrier approach. For DC- bus capacitor voltage control, a new, balance circuit is proposed. Because of its modularity, it is simple and can be easily incorporated in cascaded inverter model with any number of levels. Feedback controller design is presented with main focus on grid voltage regulation and overall system capacitor voltage balance. The validity of grid interface model and its control strategies is substantially confirmed by the extensive simulation results.

Performance Analysis of Photovoltaic Induction Motor Drive for Agriculture Purpose

&lt;p&gt;This paper presents water pumping system using renewable source (solar) without the use of chemical storage batteries. In this converter-inverter circuit is used to drive Induction motor. The Converter used here is Two Inductor boost converter (TIBC), which consists of a resonant tank, voltage doubler rectifier and a snubber circuit. TIBC is designed to drive the three phase induction motor from PV energy. TIBC converter is also known as current fed multi resonant converter having high voltage gain and low input current ripple. Converter switches are controlled through hysteresis controller and ZCS resonant topologies. Solar PV power fluctuates according to irradiation level of sunlight and hence tracking of maximum power at all time is mandatory. SPWM control with third harmonic injection is used to trigger the IGBT’s in the inverter. The development is oriented to achieve a more efficient, reliable, maintenance free and cheaper solution than the standard ones, that uses DC motors or low voltage synchronous motors. The proposed method is verified with MATLAB/SIMULINK and the system simulation confirms the performance of the proposed system.&lt;/p&gt;

Comparison of Various Levels of Parallel Multilevel Active Filter Using NPC Multilevel Inverter

&lt;p&gt;This paper puts forward the technique of reference signal generation of the reactive instantaneous power and the technique of the SPWM control signal generation of the multilevel active filter. A comparison between the source currents before and after filtering is made. Then a comparison between the different source currents of different multilevel active filters. The subjects of comparison are the total harmonic distortions (THD) of the source current. The obtained simulation results have proved that the filtering quality is improved when increasing the active filter levels. Simulations are carried out by PSIM program.&lt;/p&gt;

Artificial Optimal Fuzzy Control Strategy for Elevator Drive System by Using Permanent Magnet Synchronous Motor

There are many power electronic converters and motor drives connected together to form the electrical system of an elevator. In this paper, we have presented a modeling tool that has the advantages of utilizing capabilities of the PMSM software in detailed simulations of converters, motor drives, and electric machines. In addition, equivalent electrical models of Elevator drive system. This paper also gives a brief idea of PMSM validity as an elevator simulation tool. PMSM drive system is described and analyzed due to its importance in many applications especially in elevator applications. applications due to their high efficiency, low inertia and high torque to volume ratio. A closed loop control system with a PI control,Fuzzy, PSO in the speed loop with current controllers .The simulation circuits for PMSM, inverter, speed and current controllers include all realistic components of the drive system. Simulation results for SPWM control schemes associated with current controllers are given for two speeds, one below rated and another above rated speed. in this paper and it has been shown that the model is suitable for transient as well as steady state condition. These results also confirmed that the transient torque and current never exceed the maximum permissible value. DOI: http://dx.doi.org/10.11591/telkomnika.v14i3.7952

DESIGN AND DEVELOPMENT OF GRID TIE INVERTER WITH CLOSED LOOP SPWM SINGLE STAGE THREE SWITCH SYNCHRONIZED AND BUCK-BOOST PRINCIPLE

The project aims the devise topology of single stage, three switch, closed loop SPWM control photovoltaic inverter for grid tie residential application. Predictable buck-boost GTI used in photovoltaic application are of manifold stage inverter systems, encompass dc-ac-dc converters added to achieve a raised dc voltage before inversion. Additional stage require more power machinery and also more power loss results, Even though a two-stage buck-boost inverter can reach significantly high power capability, which introduces circuit density as well as adds up the cost. In disparity with existing system project proposes the intend of a three-switch single stage grid connected buck-boost inverter, where switching losses to a great extent reduced as number of switches and also flyback, buck boost function principles are applied to match up with solar energy accessibility variation. For switching power circuit blend of square wave and SPWM is used, with kind of combination switching frequency reduces to such a level where switching losses significantly reduced. To realize Grid synchronization Strategy sine wave beginning from grid will be used as orientation signal for SPWM. To regulate inverter immediate ac output closed loop control scheme is engaged. Implementation of simple controller format with which output is stabilized as fast as probable. Advantages of this method are established by simulation of a grid-connected single-stage three switch, closed loop SPWM buck-boost inverter..