Hysteresis Current Control Research Articles

Assessment of Total Harmonics Effects on Grid-Connected Powered Inverter Using Sine-Referenced and Static-band Hysteresis of Current Controllers

This article presents an assessment of total harmonics effects on grid-connected powered inverter using sine-referenced and static-band hysteresis of current controllers. To realize this art, current transducer, static-band and sine-referenced hysteresis current controllers, solar energy source, maximum power point tracker, grid supply and voltage source DC-AC converter are engaged. The system has these features are: (i) Light weight owing to none transformer-less system application (ii) Efficient in injection of power Under static-band hysteresis current controlled fed-back system, at upper and lower bands of 130Vand 50V, a total harmonic distortion, THD of 1.815% and output voltage, vo of 220Vrms (320V peak) were realized whereas in sine-referenced band hysteresis current controlled fed-back system at upper and lower bands of 430V and 340V, a THD of 1.019% and vo of 220Vrms are released. The computer simulations and spectral analyses of the system were presented

Fuzzy Hysteresis Current Controller for Power Quality Enhancement in Renewable Energy Integrated Clusters

Steady increase in electricity consumption, fossil fuel depletion, higher erection times of conventional plants, etc., are encouraging the use of more and more onsite renewable energy. However, due to the dynamic changes in environmental factors as well as the customer load, renewable energy generation is facing issues with reliability and quality of the supply. As a solution to all these factors, renewable energy integrated cluster microgrids are being formed globally in urban communities. However, their effectiveness in generating quality power depends on the power electronic converters that are used as an integral part of the microgrids. Thus, this paper proposes the “Fuzzy Hysteresis Current Controller (FHCC)-based Inverter” for improving the power quality in renewable energy integrated cluster microgrids that are operated either in grid-connected or autonomous mode. Here, the inverter is controlled through a fuzzy logic-based hysteresis current control loop, thereby achieving superior performance. System modelling and simulations are done using MATLAB/Simulink®. The performance analysis of the proposed and conventional inverter configurations is done by computing various power quality indices, namely voltage characteristics (swell, sag, and imbalance), frequency characteristics (deviations), and total harmonic distortion. The results reveal that the proposed FHCC-based inverter achieves a better quality of power than the traditional ST-PWM-based multilevel inverter in terms of IEEE/IEC/EN global standards for renewable energy integrated cluster microgrids application.

A NEW MULTI-MOTOR DRIVE SYSTEM BASED ON FOUR-SWITCH THREE-PHASE INVERTER TOPOLOGIES

Vietnam encourages greenhouse technology applications for high-tech agricultural production. The microclimate of greenhouses is the key factor for better plant growth. The greenhouse microclimate can be improved by control actions, such as heating, ventilation, and carbon dioxide enrichment to provide appropriate environmental conditions for crops. The multi-motor drive systems using six-switch three-phase inverter topologies are applied for greenhouse fans. In order to decrease to size and cost of effectiveness drive systems, the paper proposes a new multi-motor drive system based on four-switch three-phase inverter topologies which are applied to two-level hysteresis current controllers. The proposed solution has been tested to a four-permanent-magnet synchronous motor (PMSM) drive system. The simulation results are carried out to show the effectiveness of the proposed solution.

Microgrid Power Quality Improvement Using Active Power Conditioner

This paper discusses power system power quality issues and possible remedies using power electronics. Several worldwide standards This research shows how a Shunt active power filter can improve power quality in a microgrid system at the distribution level. The major goal of this study is to find an appropriate pulse generating strategy for improving the shunt active power filter's compensation capabilities. The device's compensating capability is mostly determined by the DC link capacitor voltage regulation. A fixed hysteresis current control approach has been employed in the past. An adaptive hysteresis current control technique has been developed here to improve the performance of a shunt active power filter. The suggested technique's performance has been verified in the MA TLAB/SIMULINK model platform under various operating conditions.

Dual-Vector Predictive Current Control of Open-End Winding PMSM With Zero-Sequence Current Hysteresis Control

Dual-inverter fed open-end winding permanent magnet synchronous motor (OW-PMSM) drive topology can extend the speed range under limited dc bus voltage, but it suffers from the zero-sequence current (ZSC) problem when with common bus configuration. Predictive current control (PCC) is a potential high-performance control method for electric drive. However, the PCC algorithm for dual-inverter system may bring a huge computational burden because of more space vectors (SVs) to traverse. In order to improve the steady-state current performance and suppress the ZSC, this article proposes a dual-vector PCC (DV-PCC) method for OW-PMSM with ZSC hysteresis control. The reference voltage vector is predicted in advance according the model. A novel sector judgment method is used to judge the sector and subsector where the reference voltage vector is located, and determines the two candidate SVs. Then the dwell time of the two candidate SVs is calculated through the projection length of the reference voltage vector. Moreover, the switching states redundancy feature of dual-inverter system is employed to suppress ZSC. As some SVs correspond to multiple switching states of different zero-sequence voltages (ZSVs), the switching state whose ZSV polarity is opposite to the ZSC polarity is selected as the output to realize the hysteresis control of ZSC. When the ZSVs of the candidate SVs contradict the hysteresis control demand, the zero-vector insertion method is used to guarantee the effective suppression of ZSC. The experiments are implemented in comparison with the existing DV-PCC method.

A Novel Control Technique Based on Multi-Objective Intelligent Routing Algorithms for Optimum Performances of 12/8 Switched Reluctance Motor

Many objects for better performances in the 12/8 Switched Reluctance Motor (SRM) have been covered in this paper. The idea aimed to a new strategy in the control of this kind of machines for technical improvement by reducing torque ripple with better speed control and economic improvement by reducing the number of switchings. Minimum torque ripple with speed control and minimum number of switchings are the objects that are addressed by combining the Multi-Objectives Particle Swarm Optimization (MO-PSO) algorithm and Hysteresis Current Control (HCC). To achieve the effectiveness of the proposed strategy, the following steps must be taken. The first step is to determine the nonlinear characteristic of 12/8 SRM by Finite Element Method (FEM) for the dynamic model and for the estimation of the instantaneous torque by using the technical look-up table. The second step is the speed control using the SRM by HCC, then pair the MO-PSO with the HCC to determine the optimal parameters for each impact parameters like the turn on, the turn off angles (θon, θoff) and the hysteresis band for the control of the number of switching. Finally, the graphical and the numerical results confirm and approve the effectiveness of the proposed association between intelligent metaheuristic algorithms and the HCC control to improve the technical-economic performance of the 12/8 SRM considering different conditional loads and speeds.

A Computationally Efficient Model Predictive Current Control of Synchronous Reluctance Motors Based on Hysteresis Comparators

Model predictive current control (MPCC) has recently become a powerful advanced control technology in industrial drives. However, current prediction in MPCC requires a high number of voltage vectors (VVs) synthesizable by the converter, thus being computationally demanding. Accordingly, in this paper, a computationally efficient MPCC of synchronous reluctance motors (SynRMs) that reduces the number of VVs used for prediction is proposed. By making the most of the simplicity of hysteresis current control (HCC) and integrating it with the MPCC scheme, only four out of eight predictions are needed to determine the best VV, dramatically reducing algorithm computations. The experimental results show that the execution time can be shortened by 20% while maintaining the highest control efficiency.

Faster Convergence Controller With Distorted Grid Conditions for Photovoltaic Grid Following Inverter System

The hysteresis current controller (HCC) for grid following inverter (GFI) system with <inline-formula> <tex-math notation="LaTeX">$LCL$ </tex-math></inline-formula>-filter is a well-known controller for its robustness, fast reference tracking, better dynamics, and easier implementation compared to other controllers. However, HCC behaves differently while integrating such a system with solar photovoltaics (PV). The PV-based GFI system requires fast convergence while transferring maximum power from PV to the grid at minimum converter losses through GFI. This paper therefore proposes a modified double-band HCC (MDBHCC) with proportional resonant (PR) controller for single-phase PV integrated GFI system with LCL-filter. The proposed algorithm implements a unipolar symmetrical PWM strategy for reducing inverter switching losses through a sequential logic with an adaptive clock. It improves the variation in switching frequency and limits the maximum switching frequency of HCC while enhancing the total harmonic distortion (THD) of the injected current into the grid at the point of common coupling. To alleviate the power quality problem and achieve zero steady state error, the proposed MDBHCC with PR control operates at lesser &#x0025; THD. Simulation and experimental results are presented, with a significant decrease in switching frequency and an improvement in grid current harmonics at both steady-state and dynamic conditions.

VSC-Based DSTATCOM for PQ Improvement: A Deep-Learning Approach

Abstract With the rapid advancement of the technology, deep learning supported voltage source converter (VSC)-based distributed static compensator (DSTATCOM) for power quality (PQ) improvement has attracted significant interest due to its high accuracy. In this paper, six subnets are structured for the proposed deep learning approach (DL-Approach) algorithm by using its own mathematical equations. Three subnets for active and the other three for reactive weight components are used to extract the fundamental component of the load current. These updated weights are utilised for the generation of the reference source currents for VSC. Hysteresis current controllers (HCCs) are employed in each phase in which generated switching signal patterns need to be carried out from both predicted reference source current and actual source current. As a result, the proposed technique achieves better dynamic performance, less computation burden and better estimation speed. Consequently, the results were obtained for different loading conditions using MATLAB/Simulink software. Finally, the feasibility was effective as per the benchmark of IEEE guidelines in response to harmonics curtailment, power factor (p.f) improvement, load balancing and voltage regulation.

Investigations on variable and constant switching frequency hysteresis controller for VSI fed IM drive

In various current controlled-pulse width modulated (CC-PWM) techniques which are extensively employed in high performance drives, hysteresis current control (HCC) offer significant simple implementation and good dynamic response. However, conventional HCC have drawbacks, such as, limit cycle oscillations, overshoot in current error, generation of sub-harmonic components in the current, and non-optimum switching of inverter voltage vectors which can create variable switching frequency. This work proposes a new constant switching current error space phasor (CESP)-based hysteresis controller with a simple online computation of the boundary and phase voltage harmonic spectrum similar to voltage controlled bus clamping PWM (VC-BCPWM)-based VSI fed induction motor drive. The error boundary computed using voltage and current errors in the present sampling interval is used for identifying next vector to be switched. The current controller using CESP approach is simulated using MATLAB Simulink and experimentally verified on 2.2 kW IM drive.

Thirteen-Level UXE-Type Inverter With 12-Band Hysteresis Current Control Employing PSO Based PI Controller

This work presents hysteresis control applied to UXE-type inverter topology with a PI (Proportional Integral) controller, where the gains are derived by Particle Swarm Optimization (PSO). The investigated UXE inverter can generate a thirteen-level output voltage waveform, which results in lower switching losses. It can boost the output voltage to 1.5 times the applied input DC source voltage. Satisfactory inverter operation is ensured by employing twelve-band hysteresis current control. The tuning of the PI controller required for the closed-loop hysteresis current control is achieved by nature-inspired PSO algorithm. A comparative analysis is also performed after obtaining the results applying nature-inspired PSO and conventional Ziegler Nichols (ZN) methods. The effectiveness of the control strategy is verified in the MATLAB Simulink and further validated in experiment using TMS320F28379D and also with Typhoon Hardware in Loop Technology.

Power quality improvement using model predictive control based shunt connected custom power device in a single phase system

Abstract The performance evaluation of a single-phase shunt-connected custom power device (SC-CPD) for current quality improvement is discussed in this paper. The SC-CPD performance is compared based on the linear triangle-comparison pulse width modulation (TC-PWM) control, hysteresis current control (HCC), and the predictive non-linear switching control strategies. The predictive switching control is implemented using the finite control set-model predictive control (FCS-MPC). The switching control techniques’ operational and implementation features are discussed for the given control objectives of the SC-CPD for a particular nonlinear load. Basic functional case studies with sinusoidal and non-sinusoidal supply mains in the presence of non-linear loads are presented to illustrate the appropriateness of the switching techniques. The SC-CPD model and control methodologies are developed in the MATLAB/Simulink environment, including designing of various circuit components. Finally, performance simulation results using the switching techniques have been compared and validated using OPAL-RT 4510-based real-time simulations.

Modeling of hybrid active power filter using artificial intelligence controller: hardware and software prospective

&lt;span lang="EN-US"&gt;The power factor is a significant concern in power systems. The significant power loss occurred due to electronic and electrical equipment damages affected by the deviation of physical characteristics, including voltage, current, and frequency parameters.The power loss and quality issues were resolved by introducing filtering techniques in electronic and electrical equipment. Many filtering techniques include passive filtering (PF), Active power filter (APF), and many hybrid approaches are already available. Most of these methods use proper compensation controlling approaches and failed to minimize the total harmonic distortion (THD), and harmonic mitigation in power systems has its best. In this article, an efficient Hybrid-APF using Artificial-Neuro Fuzzy interface system (ANFIS) for software and hardware perspective is designed. The proposed approach uses hybrid controlling strategies which include PI with artificial intelligence (ANFIS) controller, to control the power losses for H-APF. Additionally, current compensation is achieved by PQ-theory, followed by Hysteresis-Current- Controller (HCC). The hardware architecture of ANFIS with HCC is designed to improve the chip-area for real-time power applications.The present work analyzed by simulating the voltage and current waveform. The proposed-H-APF using ANFIS controller, both software and hardware approaches, is compared with other control techniques like H-APF with PI and Fuzzy logic controller by concerning THD,Reactive power, and Different Harmonics and loads improvements.&lt;/span&gt;

A simple control strategy and dynamic energy management for the operation of combined grid-connected and standalone solar photovoltaic applications

There is an increased focus on energy savings in low-voltage DC (LVDC) loads for home appliances. The use of LVDC for the local distribution system enables easier integration with renewable sources. This work presents the control and management of power flow to DC loads in grid-tied photovoltaic (GPV) systems. This system provides bi-directional flow of power from the DC load to the AC grid, using a pulse width modulation (PWM) technique, employing a voltage source inverter between the DC nano grid and the AC main grid. The bidirectional converter controls the active power transferred in both directions while operating at unity power factor (UPF). The modified three-level hysteresis current controller and the voltage controller are designed as the inner loop and the outer loop, respectively, to control the bi-directional power flow. The corresponding grid voltages and currents are used to generate the reference currents. The proposed system has been validated through MATLAB/Simulink simulations and experimentation on a prototype system developed in the laboratory controlled by the dSPACE 1103 real-time digital controller board. The results show that a regulated DC voltage is obtained for dynamic changes of source and load like in a real-time environment. The control strategy with its validation shows the efficacy of the proposed system.

Inverter current control for reactive power compensation in solar grid system using Self-Tuned Fuzzy Logic Controller

The solar photovoltaic (PV) systems have gained more attention in renewable energy production due to their cost efficiency and reliability. Typically, reactive power compensation and harmonics elimination are challenging and demanding tasks for improving the efficacy of grid-connected solar PV systems. For this purpose, many research works developed different converter and controller topologies for solving the power quality issues in grid-PV systems. But, it limits the problems of increased harmonics, computation complexity, inefficiency and reduced performance outcomes. Thus, this research aims to develop an integrated hysteresis current controller and Self-Tuned Fuzzy Logic (SFLC) based MPPT controllers for eliminating the harmonics and unbalanced current in single-phase grid systems. Also, it helps to extract the maximum amount of power from the solar PV array. The LUO converter is deployed to reduce ripple contents. The Phased Locked Loop (PLL) based synchronization is performed to maintain the phase angle, frequency and magnitude levels of source power. Moreover, the hysteresis current controller for the inverter has been specifically designed to reduce the THD of the system under IEEE519_1992 regulations. During experiments, both the simulation and hardware results have been evaluated for validating the performance of the proposed controller design.

Space vector PWM ‐based current error boundary investigations for three‐level VSI fed induction motor drive

Field oriented control (FOC) of induction motor (IM) powered by a three-level voltage source inverter (3L -VSI) with space vector (SV) based continuous and dis -continuous pulse width modulation (PWM) is presented in this paper. The current error variations in each sector with above-mentioned PWM techniques are monitored and analyzed mathematically. These boundary investigations play a great role in the implementation of Current Error Space Phasor (CESP) based hysteresis current controller (HCC) which incorporates the advantages of a constant switching frequency PWM fed three-level inverter (3LI) into highly dynamic current controlled – voltage source inverter. As a preliminary step, FOC of IM with the conventional space vector PWM and bus clamping PWM (BC30 and BC60) fed 3LI have been simulated using SIMULINK toolbox of MATLAB. Transient analysis of the drive with acceleration, deceleration, and load change studies with different switching schemes are analyzed with d SPACE RTI1103 experimentation on a 2.2 kW three-phase IM drive in detail.

The impacts of control systems on hybrid energy storage systems in remote DC-Microgrid system: A comparative study between PI and super twisting sliding mode controllers

The adoption of hybridized energy storage systems (HESSs) in standalone photovoltaic (PV) systems instead of single battery ESSs offers featured capabilities of high power/energy densities and extended lifespans to supply power through controllable power converters using robust controllers. This paper examines the HESS control subjected to pulsed power balance changes through splitting frequency parts of load requirements among battery and supercapacitor. The filtering-based frequency decoupling method ensures sharing control of HESS currents using a dual-loop structure with high control dynamic to track battery currents considering Bus voltage abnormalities, and a hysteresis current controller (HCC) to command supercapacitor currents using battery current setpoints. Three settings are used to assess the superior performance of the HESS: combining Proportional-Integral (PI) with Super-twisting sliding mode (STSMC) controllers in dual-loop control structures, time-constants, and current bandwidths of the HCC. Upon competitive findings, the optimal settings approve minimum Root-Mean-Square-Error (RMSE) and Mean-Absolute-Error (MAE) of bus voltage, HESS currents, power deficits, besides load-meeting rates. The STSMC outperforms due to its super-spiral curve offering rapid convergence and reduced chattering that influences the stability in conventional SM. Then, less stressed and smooth behavior of the HESS, stable bus voltage, smooth power flowing, and high load sharing efficiency are achieved.

An efficient compensation of modified DSTATCOM for improving microgrid operation

This paper proposes a design for a modified distribution static compensator (DSTATCOM) with a proposed current controller for microgrid (MG) applications. The modified DSTATCOM is incorporated in a three-phase four-wire network system to deal accurately at grid connected mode with balanced, unbalanced and excursion load for both nonlinear and inductive loads. Moreover, it handles the stability issues of the MG at fault caused islanding incidents. The design criteria of the modified DSTATCOM parameters is presented and discussed. The hysteresis current controller is introduced to drive the voltage source converter (VSC) and its reference voltage signal is generated based on the instantaneous symmetrical components theory (ISCT). Matlab/Simulink software is used to verify the performance of the modified DSTATCOM with the proposed controller under different load types and loading conditions for grid connected mode and islanded mode of MG operation. Based on the simulation results, the power factor is improved and the non-linear harmonics currents are compensated therefore the harmonic distortion of the supply currents and voltage are reduced, moreover the stability operation at fault cause islanding is maintained. The results show the superiority of the proposed modification of DSTATCOM in dealing with unbalanced, distorted and bad power factor system in comparing with conventional DSTATCOM.

A Current Amplifier Circuit and Control Strategy Based on FPGA

With the extensive application of electric vehicles, energy storage systems and other power electronic equipment, the research on large capacity controllable current source will be an important direction in the future. This paper proposes controllable current source controlled by a full digitally hysteresis current based on field programmable gate array(FPGA), in which the single phase full bridge topology is adopted as the main circuit of current source. The two levels and three levels hysteresis current control strategies are analyzed and compared with the platform of PSCAD/EMTDC. The user defined component was adopted to realize the two difference control strategies with fortran language program. The simulation results verified that the two levels hysteresis current control strategy is much more fit for the controllable current source. Finally, a prototype is designed and fulfilled and it is controlled by the digitally controller with FPGA. The hysteresis current control is realized by FPGA controller with VHDL programming. The experimental results show that the researched hysteresis current control technology is effective for the current amplifier

Optimum Switching Angles Control of SRM for Electric Vehicle Applications

Switched Reluctance Motor (SRM) drive is being gradually used in industrial applications, including electric vehicles (EVs), due to several advantages over conventional motors. However, the nonlinear magnetic characteristics of the motor make its controller very complicated. This paper presents a simplified procedure to obtain the optimal switching angles under hysteresis current control SRM drive over a wide range of speeds. A multi-objective optimization technique is applied to determine the optimal switch on and switch off angles that achieve the optimum combination of maximum average torque with minimum torque ripple and copper loss. A searching algorithm is developed for each operating point to define the maximum average torque and the minimum torque ripple and copper losses, as they vary for different currents and motor speeds. Then the optimal values of switching angles are stored in the lookup tables to build a MATLAB model of the SRM drive system. Finally, simulation and experimental results are presented to show the validity and effectiveness of the proposed controller.