Width Modulated Voltage Source Inverter Research Articles

Power quality improvement by using photovoltaic based shunt active harmonic filter with Z-source inverter converter

Introduction. The major source of energy for a long time has been fossil fuels, however this has its drawbacks because of their scarcity, exhaustibility, and impossibility of reusing them. Presently, a shunt active harmonic filter-equipped two-stage solar photovoltaic system is showing off its performance shunt active harmonic filter. The global power system has been impacted by current harmonics during the most modern industrial revolution. Novelty. The proposed work is innovative, by adopting the hysteresis modulation mode with Z-source inverter to enhance the performance of the system. Furthermore, the shunt active harmonic filter also get assists in this system for better improvement in the quality of power. Purpose. By incorporating an impedance source inverter and a photovoltaic shunt active harmonic filter methods, harmonic issues are mitigated. Methods. Load compensation is one of the services that the shunt active harmonic filter offers, in addition to harmonic compensation, power factor correction, and many other functions. The current pulse width modulation voltage source inverter method is more expensive, requires two converters owing to its two-stage conversion, has significant switching losses, and has a low rate of the reaction. The new model, in which the voltage source inverter is substituted out for a Z-source inverter converter, has been developed in order to address the problems of the existing system. Results. Rather than using a hybrid of DC-DC and DC-AC converters, the suggested system uses a shunt active harmonic filter that is powered by a photovoltaic source using a Z-source inverter. Utilizing Z-source inverter helps to address the present issues with conventional configurations. Practical value. By using software MATLAB/Simulink, this photovoltaic shunt active harmonic filter technique is analyzed. Shunt active harmonic filter, which produces compensatory current from the reference current obtained as from main supply, is powered by the photovoltaic array.

Modeling & implementation of DRLA based partially shaded solar system integration with 3-ϕ conventional grid using constant current controller

Renewable Energy Resources (RERs) are widely used on the concern of global environment protection. Solar energy systems play an important role in the generation of electrical energy, remarkably minimize the utilization of nonrenewable fuel sources. Solar energy can be extracted and transformed into electrical energy via solar photovoltaic process. Several traditional, soft computing, heuristic, and meta-heuristic maximum power point tracking (MPPT) techniques have been developed to extract Maximum Energy Point (MEP) from the solar photovoltaic modules under different atmospheric conditions. In this manuscript, the combination of reinforcement learning algorithm (RLA) and deep learning algorithm (DLA) called deep Reinforcement Learning Algorithm based MPPT (DRLAMPPT) is proposed under partial shading conditions (PSC) of the solar system. DRLAMPPT can deal with continuous state spaces, in contrast to RL it can be operated only with discrete action state spaces. In this proposed DRLAMPPT, deep deterministic policy gradient (DDPG) solves the problem of continuous state spaces are involved to reach the GMEP in photovoltaic systems especially under PSC. In DRLAMPPT, the representative's strategy is parameterized by an artificial neural network (ANN), which uses sensory information as input and directly sends out control signals. This work develops a 2 kW solar photovoltaic power plant comprises of a photovoltaic array, DC/DC step-up converter, 3-Φ Pulse Width Modulated Voltage Source Inverter (PWM-VSI) integrated with conventional power grid using Constant Current Controller (CCC Effectiveness of the proposed DRLAMPPT with CCC can be validated through an experimental setup and with MATLAB. Simulation and tested at different input conditions of solar irradiance. Experimental results prove that, in comparison to existing MPPTs, suggested DRLAMPPT not only attains the best efficiency and also adopts the change in environmental conditions of the photovoltaic system at a much faster rate and able to reach the GMEP within 0.8 s under PSC. Experimental and simulation results also prove that suggested CCC with LC filter makes the inverter output voltage and the grid voltage are in phase at the lower value of THD i.e. 1.1% and 0.98% respectively.

Fast Calculation of Electromagnetic Forces in IPMSMs Under PWM VSI Supply Based on Small-Signal Time-Harmonic Finite Element Method

This paper introduces a novel method for fast calculating the electromagnetic forces in interior permanent magnet synchronous machines (IPMSMs) under pulse width modulation (PWM) voltage source inverter (VSI) supply based on the small-signal time-harmonic finite element analysis (THFEA), which has been successfully utilized for fast calculating the PWM-induced losses in silicon steel sheets and permanent magnets. Based on the small-signal THFEA, the functional relationships between high-frequency harmonic voltages (HFHVs) and corresponding airgap flux densities are established, which are used for calculating the flux density spectra caused by each HFHV in the PWM voltage spectra. Then, the superposition principle is applied for calculating the flux density spectra caused by fundamental currents and all HFHVs, which are converted to the electromagnetic force spectra at last. The relative errors between the force density spectra calculated with the proposed method and those obtained from traditional time-stepping finite element analysis (TSFEA) using PWM voltages as input are within 3.1%, while the proposed method is 24 times faster than the traditional TSFEA.

Optimal Management Energy System and Control Strategies for Isolated Hybrid Solar-Wind-Battery-Diesel Power System

This paper proposes optimal control strategies of a standalone Hybrid Power System (HPS) to supply sustainable and optimal energy to an isolated site with improved quality of electrical energy. A topology of Isolated Hybrid Power System (IHPS) is proposed, consists of: a Photovoltaic System (PVS), a Wind Energy Conversion System (WECS), electronic power devices controlled to maximize energy production from renewable sources and to maintain the constant DC-link voltage, a Battery Energy Storage System (BESS), Diesel Generator (DG), and a Pulse Width Modulation (PWM) Voltage Source Inverter (VSI) located at the load-side end. In addition, a novel control strategy has been proposed, in this work, to maximize the power from the PVS. This presented strategy, based on the combination between Perturb and Observe (P&O) algorithm and the Fuzzy PI Controller (FPIC), presents a good performance, especially in the dynamic state compared to the classical algorithm P&O. A supervisory control algorithm has been elaborated to manage the energy flows between the devices of the hybrid system to make the decision of the optimal operating mode in order to ensure a continuous supply of the load with minimum usage of batteries and DG. The simulation results developed in the Matlab/Simulink environment are applied to show the efficiency and performance of the proposed control strategies in terms of power optimization and energy management. Doi: 10.28991/esj-2021-01262 Full Text: PDF

Characterization of three phase solid state VAR compensation scheme in three phase pulse width modulation voltage source inverter

The principle of a three phase solid state VAR compensation (SSVC) system that uses a three-phase pulse width-modulated (PWM) Voltage-Source Inverter (VSI) is presented and analyzed. The proposed SSVC system can compensate for leading and lagging displacement power factor and the PWM is used as a means of reducing the size of reactive components. The significant aspect of the presented VAR compensator is the adjustment of the angle difference between the static fundamental circuit output voltage and the utility supply voltage in order to optimize the alternating current (a.c.) power factor to a non-linear load. The SSVC system is analyzed under self-controlled DC bus voltage operating conditions. Other areas of investigation include the design of SSVC reactive components. The dynamic analysis is carried out in a d-q reference frame to verify the performance of the VAR compensator in terms of speed of response and stability. Analysis and stability plots generated confirm a high performance static VAR compensator. Finely, the findings of present research work were found within good agreement with some other workers.

Performance Improvement of a Distributed Generation System Using Unified Power Quality Conditioner

This paper deals with performance improvement of a distributed generation (DG) system using unified power quality conditioner (UPQC). Despite of the several benefits of DG like excellent energy supply, reducing expansion of power distribution system, environmental friendly and so on, there are several challenges existing due to the integration of DG with the grid or operating it in standalone mode. Power quality (PQ) issue is one of the main technical challenges in DG power system. Moreover, harmonic and voltage sag compensation in a DG networks has significantly reduced PQ, which affects the stability of the system. Hence, in this paper, impact of PQ issues in an adopted standalone DG system (comprising of solar, wind and fuel cell based renewable energy sources) is investigated in the presence of UPQC. The realization of UPQC is carried out using conventional synchronous reference frame (SRF) and modified SRF (MSRF) techniques for reference current generation with pulse width modulation voltage source inverter technique for generation of pulses for the inverter along with a PI controller for regulation of DC-link capacitor voltage. The voltage sag compensation with current and voltage harmonics are estimated at different source (ideal and non-ideal) conditions with different control scheme like SRF and MSRF technique. The simulation model of conventional SRF and MSRF technique based UPQC is developed under MATLAB/SIMULINKR environment. The result obtained validates the superiority of proposed technique over others in terms of harmonics elimination and sag compensation.

Evaluation of the High Performance Indirect Field Oriented Controlled Dual Induction Motor Drive Fed by a Single Inverter using Type-2 Fuzzy Logic Control

In this paper, a high-performance indirect field-oriented controlled dual Induction Motor (IM) drive fed by a single inverter using type-2 fuzzy logic control will be presented. At first, the mathematical model of the IM is implemented in the d-q reference frame. Then, the speed control of the Dual Induction Motor (DIM) operating in parallel configuration with Indirect Field Oriented Control (IFOC) using PI and type-2 Fuzzy Logic Controller (T2-FLC) will be presented. For the control of this system, a DC supply and a Space Vector Pulse Width Modulation (SVPWM) voltage source inverter are introduced with constant switching frequency. Also, the performance of T2-FLC, which is based on the IFOC, is tested and compared to those achieved using the PI controller. The simulation results demonstrate that the T2-FLC is more robust, efficient, and has superior dynamic performance for traction system applications.

Cascaded controller for a standalone microgrid‐connected inverter based on triple‐action controller and particle swarm optimisation

In this study, power quality (PQ) improvement has been addressed, in the form of total harmonic distortion (THD) minimisation, as well as, voltage regulation using two cascaded schemes. The first scheme is the optimised triple action controller (TAC)-based pulse width modulated voltage source inverter. TAC consists of a proportional resonant controller, selective harmonic compensator, and a new added current-assisted feed forward controller. The second scheme is the optimised cascaded dual-level control of a standalone microgrid. Cascaded level control consists of droop, secondary, and synchronisation control loops. The two approaches have been optimised for best parameter selection out of the possible solution space using a particle swarm optimisation algorithm to satisfy the study objectives. The optimisation objectives/constraints were to minimise THD and minimise overshoot/undershoot, rise time, and steady-state error for voltage compensation under two disturbance scenarios, sudden load change, and voltage flicker injection as a power frequency disturbance. These research results have been compared to other existing simulation and experimental work. The results proved to be better in output voltage, frequency, response time, and THD. Furthermore, the proposed schemes ensure power factor improvement, high efficiency, overall system PQ, and reliability at various load conditions.

Generic pulse width modulation model, based on generalized inverses and applied to voltage source inverters

PurposeThis paper aims to develop a method for a unified model of pulse width modulation (PWM) voltage source inverters (VSI). This generic method, based on a common and easy-to-use carrier-based modulation, allows to generate the exhaustive solution set for a given PWM-VSI.Design/methodology/approachThe use of the generalized inverse theory is developed to express the PWM solution set for the duty cycle. Indeed, the infinite number of PWM solutions is demonstrated. To explore this solution set, the unified model described exhibits degrees of freedom. The admissible margins to set the degree of freedom are highlighted. Some experimental results are presented.FindingsIt is demonstrated how the degree of freedom can be directly connected with efficiency indicators such as common mode voltage, inverter linearity and switching losses. The expression of the PWM solution set boundaries is clearly expressed.Research limitations/implicationsFurther studies should explore how the degree of freedom can be connected with parameters associated with the current (and not the voltage as described in this paper).Practical implicationsThe paper includes implications for the development of a more generic approach for PWM multilevel VSI.Originality/valueThis paper fulfils a mathematical frame to ease the expression of PWM scheme.

Power Loss Analysis Model of a Dc-Dc Buck-Boost Converter with an Interfaced Three Phase Inverter for Medium Voltage Application

This paper presents a comprehensive mathematical modelling of a DC to DC Buck-Boost converter. The different power losses associated with the Buck-Boost circuit are also presented. Analysis of the converter power loss is graphically represented at varied duty cycles and load resistance values. A low frequency pulse width modulated inverter is interfaced with the Buck-Boost converter using MATLAB/SIMULINK. For an efficient performance and attenuation of low order harmonics, the low frequency pulse width modulated inverter is substituted with a high frequency pulse width modulated voltage source inverter. A comparison is therefore drawn to show the significant change in the percentage harmonic reduction of the two different frequency modulations. All simulation results are achieved using MATLAB 7.14 version. The simulation results however show that Mosfet switching loss decreases with an increase in the duty cycle whereas Diode and Inductor conduction losses increase with an increase in the duty cycle values.

Comparative Analysis of Induction Motor Drive with Chopper Controlled SPRS Employing Various Inverter Configurations

ABSTRACTSlip power recovery scheme (SPRS) employing buck or boost chopper has restrictions on minimum turn-on power or voltage stability. In the proposed scheme, the buck-boost chopper and inverter with various switching devices that enhances the performance characteristics of induction motor drive (IMD) have been made. A mathematical model is derived for buck-boost chopper. Investigations of IMD using SPRS with pulse width modulated voltage source inverter (PWMVSI) and buck-boost chopper is carried out. Simulation results analysis reveals that metal-oxide-semiconductor field effect transistor and insulated gate bipolar transistor chopper has improved the power factor and efficiency of IMD and PWMVSI reduced total harmonic distortion of the supply.

Generic Modeling of N-Level Pulse Width Modulation Voltage Source Inverters and their Control

A generic and mathematic tool is adapted and used for pulse width modulation inverter modelling and control. The model is developed on the elementary switching cell and finally extended to some N-level topologies and three-phase inverters. Based on the generalized inverses, the solution set of pulse width modulation carrier based scheme is highlighted. The degree of freedom highlighted for the modulation control are linked to the architecture described. A specific example is illustrated and based on a H-bridge 3 level topology.

Measurement and Analysis of Power in Hybrid System

Application with renewable energy sources such as solar cell array, wind turbines, or fuel cells have increased significantly during the past decade. To obtain the clean energy, we are using the hybrid solar-wind power generation. Consumers prefer quality power from suppliers. The quality of power can be measured by using parameters such as voltage sag, harmonic and power factor. To obtain quality power we have different topologies. In our paper we present a new possible topology which improves power quality. This paper presents modeling analysis and design of a pulse width modulation voltage source inverter (PWM-VSI) to be connected between sources, which supplies energy from a hybrid solar wind energy system to the ac grid. The objective of this paper is to show that, with an adequate control, the converter not only can transfer the dc from hybrid solar wind energy system, but also can improve the power factor and quality power of electrical system. Whenever a disturbance occurs on load side, this disturbance can be minimized using open loop and closed loop control systems.

SPACE VECTOR PULSE WIDTH MODULATION OF FOUR-SWITCH VOLTAGE SOURCE INVERTER FEEDING THREE PHASE INDUCTION MOTOR

An analytical model with a new space vector pulse width modulation Voltage source inverter technique method of four-switch three-phase inverter (FSVPWM) feeding induction motor is presented. This paper presents a low cost inverter employing only four switches, four diodes and a split capacitor bank in the dc-link. This work is motivated by the need of an efficient and flexible modulation method, which is optimized with respect to minimum electrical motor torque. The proposed modulation strategy for the four-switch operation has the same symmetry as in a classical six-switches space vector pulse width modulation inverter (SSVPWM). The common mode voltage generated by the four-switch space vector pulse width modulation three-phase converter is evaluated and compared to that provided by the standard six-switch space vector pulse width modulation three-phase inverter. Simulation result are presented to demonstrate the feasibility of the proposed approach.

Super Lift DC-DC Luo Converter based VSI Fed Asynchronous Motor of a Standalone PV System

This paper offers the analysis of super lift DC-DC Luo converter under the various irradiation of the PV system for driving asynchronous motor with the help of closed loop PI controller based voltage source inverter. In order to track the maximum output power from the PV panel, the INC Maximum power point tracking algorithm is also implemented along with the Super lift DC-DC Luo Converter. The maximum power point tracking of the PV output for all climatic conditions is a key aspect to maximize the efficiency of the PV panel output for successful PV applications. So this proposed method is designed and analyzed for changing climatic condition to drive variable speed asynchronous motor using pulse width modulated voltage source inverter in closed loop control. The Photo Voltaic output voltage, converter voltage and motor speed has been recorded and analyzed by using MATLAB/Simulink software.

Multi-level integrated optimal design for power systems of more electric aircraft

This paper proposes a multi-level optimal design method for a complex actuation system of more electric aircraft. The multi-level structure consists in sharing the optimization process in several levels, here 2, a “system level” which involves main coupling variables and a “component level” with one optimization loop for each device. The interest of this method is to separate the optimal design of each component, making easier the convergence of loops. This method is applied to a relatively complex power conversion system including a high speed permanent magnet synchronous machine (HSPMSM) supplied by a pulse width modulation (PWM) voltage source inverter (VSI) associated with a DC-link filter. Its interest is shown through a comparison with classical design approaches employed in previous works.

A Tactical Chaos based PWM Technique for Distortion Restraint and Power Spectrum Shaping in Induction Motor Drives

The pulse width modulated voltage source inverters (PWM-VSI) dominate in the modern industrial environment. The conventional PWM methods are designed to have higher fundamental voltage, easy filtering and reduced total harmonic distortion (THD). There are number of clustered harmonics around the multiples of switching frequency in the output of conventional sinusoidal pulse width modulation (SPWM) and space vector pulse width modulation (SVPWM) inverters. This is due to their fixed switching frequency while the variable switching frequency makes the filtering very complex. Random carrier PWM (RCPWM) methods are the host of PWM methods, which use randomized carrier frequency and result in a harmonic profile with well distributed harmonic power (no harmonic possesses significant magnitude and hence no filtering is required). This paper proposes a chaos-based PWM (CPWM) strategy, which utilizes a chaotically changing switching frequency to spread the harmonics continuously to a wideband and to reduce the peak harmonics to a great extent. This can be an effective way to suppress the current harmonics and torque ripple in induction motor drives. The proposed CPWM scheme is simulated using MATLAB / SIMULINK software and implemented in three phase voltage source inverter (VSI) using field programmable gate array (FPGA).

Sliding Mode Control of Induction Motor with Vector Control in Field Weakening

This paper presents a vector control sliding mode control (SMC) scheme in the field weakening (FW) region with optimal flux based algorithm. The observation of the rotor flux and stator flux components are also included. This work proves the advantages of vector controlled IM for high performance application in the industry. The vector control ability for easy FW and full voltage and current utilization of inverter fed IM to ensure a wide range of sufficient speed and torque operation was investigated in this work. In a sensorless vector controlled IM, the speed must be estimated using voltage and current components. The parameter variations is the main problem in the high speed operation of IM so that, the sensorless speed estimation through SM technique in the FW region with optimal flux measurement is presented. Space vector pulse width modulation (SVPWM) voltage source inverter is utilized in the algorithm. The simulation results shows the effectiveness of this algorithm at all speed range of operation.

Performance improvement of three-phase self-excited induction generator feeding induction motor load

In this paper, the transient and steady-state performances of an isolated self-excited induction generator driven by a wind turbine and feeding power to a dynamic load such as a three-phase induction motor are analyzed. Mathematical modeling and simulation study of the whole system, including the wind turbine, induction generator, capacitor, pulse width modulated voltage source inverter, and dynamic load, are carried out with closed-loop voltage and frequency controller. The complete system is modeled in the stationary $d-q$ frame and validated by comparing simulation and experimental results at no-load. The same mathematical model is then used to study the transient performance of the self-excited induction generator supplying to a dynamic load. When the induction motor is connected to the induction generator without any voltage and frequency controller, it causes severe transients in electrical and mechanical variables of the generator. Due to the large starting-current requirement of the induction motor, there is a collapse of the terminal voltage of the generator. A bidirectional pulse width modulated source inverter with DC link battery is connected with the generator and operated in closed-loop control mode to maintain voltage and frequency and to operate the induction motor successfully with variable wind speed and mechanical load.

Robust Sensorless Sliding Mode Flux Observer for DTC-SVM-based Drive with Inverter Nonlinearity Compensation

This paper presents a robust and speed-sensorless stator flux estimation for induction motor direct torque control. The proposed observer is based on sliding mode approach. Stator electrical equations are used in the rotor orientation reference frame to eliminate the observer dependence on rotor speed. Lyapunov’s concept for systems stability is adopted to confine the observer gain. Furthermore, the sensitivity of the observer to parameter mismatch is recovered with an adaptation technique. The nonlinearities of the pulse width modulation voltage source inverter are estimated and compensated to enhance stability at low speeds. Therefore, a new method based on the model reference adaptive system is proposed. Simulation and experimental results are shown to verify the feasibility and effectiveness of the proposed algorithms.