Digital Control Technique Research Articles

Enhanced the Efficiency of AC to DC Power Adapter

AC to DC Power adapter or power converter is a vital area of research nowadays is efficiency enhancement. In this research work we designed two circuit of 45 watt AC to DC power adapter and we used different diode in both circuit. First circuit which we designed which we considerd as real circuit and we used 1N4148 diode in this circuit full bridge rectifier. And simulate this circuit in LTSPICE software. After analysis the result and using the latest Efficiency Enhancement, High-Frequency Operation, Wide Bandgap Semiconductors, Miniaturization and Integration, eliability and Lifetime, Digital Control Techniques, Power Factor Correction, Renewable Energy Integration, Multi-Port Converters, Harmonic Distortion and EMI, Smart Grid and Demand Response, Environmental Impact and Sustainability, Biomedical Applications, and Safety and Standardization factors because These areas of research collectively contribute to the advancement of AC to DC power conversion technology, making it more efficient, reliable, and adaptable to the evolving needs of various industries. We design second circuit which we consider as ideal circuit we used MURS320 diode ideal circuit full bridge rectifier. And we simulate this circuit in LTSPICE software and analysis the simulation result. We get 2.5% efficiency in ideal circuit of 45 watt AC to DC power adapter

A robust PIλDµ controller for enhancing the width of the molten pool and the tracking of welding current in gas metal arc welding (GMAW) processes

ABSTRACT By utilizing advanced power electronic devices and digital control techniques in a high-speed welding power supply, it is possible to achieve self-regulation of the electrode contact tube to work-piece distance. This innovation offers a range of customizable features that can enhance and automate the gas metal arc welding (GMAW) process. The focus of this paper is on investigating the dynamic characteristics of a self-regulated consumable electrode, under step changes in the distance between the torch and the work-piece over time. The key components of arc welding processes have been examined, and a fractional PID (PIλDµ) regulator has been developed to maintain the welding current within a predetermined range during both the melting phase and the short-circuiting of the electrode wire. In this study, a weighted sum multi-objective fitness function is utilized to optimize the parameters of a fractional PID regulator using the Bacterial Foraging Optimization (BFO) algorithm. The fitness function incorporates various error criteria, such as Integral Absolute Error (IAE), Integral Time Absolute Error (ITAE), Integral Time Square Error (ITSE), and Integral Square Error (ISE), each with its own assigned weight. To demonstrate the effectiveness of the proposed PIλDµ controller over a conventional PID controller, numerical simulations are performed using MATLAB/SIMULINK software. The simulations also aim to provide insights into the mechanisms that govern the changes in arc voltage and current as the arc length varies, also shedding light on the underlying mechanisms involved. Based on the simulation outcomes, it can be concluded that the automatic arc welding control system utilizing the optimal PIλDµ controller is capable of delivering excellent performance.

양방향 경계모드 벅/부스트 컨버터의 디지털 제어기법

This paper presents the digital control techniques of a bidirectional CRM(critical-conduction mode) buck(boost) converter, a dead-time design method that optimizes ZVS(zero-voltage switching) and valley-switching operation, and a switching-frequency limitation that ensures stable converter operation. To verify the feasibility of the design, a Si-MOSFET-based bidirectional CRM buck(boost) converter is built with 260-430 V input, 160-240 V output, and 1.0 kW rated capacity. The bidirectional CRM converter achieves an efficiency of up to 99.6% at buck mode and 98.7% at boost mode under rated load conditions.

Smart Grid Communication Networks for Electric Vehicles Empowering Distributed Energy Generation: Constraints, Challenges, and Recommendations

Modern communication networks and digital control techniques are used in a smart grid. The first step is to classify the features of several communication networks and conduct a comparative investigation of the communication networks applicable to the smart grid. The integration of distributed generation has significantly increased as the global energy demand rises, and sustainable energy for electric vehicles and renewable energies worldwide are being pursued. Additional explanations for this surge include environmental concerns, the reforming of the power sector, and the advancing of small-scale electricity generation technologies. Smart monitoring and control of interconnected systems are required to successfully integrate distributed generation into an existing conventional power system. Electric-vehicles-based smart grid technologies are capable of playing this part. Smart grids are crucial to avoid becoming locked in an obsolete energy infrastructure and to draw in new investment sources and build an effective and adaptable grid system. To achieve reliability and high-quality power systems, it is also necessary to apply intelligent grid technologies at the bulk power generation and transmission levels. This paper presents smart grid applicable communication networks and electric vehicles empowering distributed generation systems. Additionally, we address some constraints and challenges and make recommendations that will give proper guidelines for academicians and researchers to resolve the current issues.

Flexural behavior of the UHPCC containing glass powder as partial substitute of cement/silica fume

This study aims to achieve the sustainability and environmental protection of ultra-high performance cementitious composite (UHPCC) by substituting cement/silica fume with glass powder (GP), and to investigate the influence of various GP substitution levels on flexural behavior. The damage patterns of GP-UHPCC are also investigated by using digital image control technique and RFPA3D program. The crack opening displacement, crack length, internal damage degree of all test series with various GP substitution levels were quantitatively characterized. The results indicate that GP as partial substitution in UHPCC is able to contribute to improving flexural strength. The energy absorption capacity of the specimen with 20% GP substitution level in all loading phases is the largest among all specimens. In addition, the crack area ratio and AE-accumulative energy of high GP substitution levels (15%–30%) is obviously higher than that of low levels (0%–10%). Generally speaking, GP substitution level of 15%–30% is found the most effective range for improving flexural behavior in this study.

Design, implementation and performance evaluation of different digital control techniques for current controlled DC-DC Buck converter

The paper presents modelling, control architecture, analysis and design of digital compensators for single feedback-loop voltage mode control as well as two feedback-loop average current mode control and peak current mode control of current controlled DC-DC Buck converter operating in continuous conduction mode with output current as control variable. The compensators are derived using digital redesign approach, simulated on MATLAB, implemented as control algorithms on Texas Instruments' 32-bit TMS320F28069M microcontroller platform, and experimentally validated by testing with a laboratory prototype of current controlled Buck converter. Simulation and experimental results are discussed, compared and evaluated for converter output current performance in tracking reference current signal as well as in regulation against input voltage and load disturbances. Salient features of each control technique are identified and described to determine its suitability in applications of DC-DC converters requiring controlled output current.

Design, Implementation and Performance Evaluation of Different Digital Control Techniques for Current Controlled DC-DC Buck Converter

Design, Implementation and Performance Evaluation of Different Digital Control Techniques for Current Controlled DC-DC Buck Converter

Peak and Valley Current Control for Cuk PFC Converter to Reduce Capacitance

Traditional power factor correction (PFC) converters usually employ a large electrolytic capacitor to ensure a stiff output voltage. However, the electrolytic capacitor is not expected in terms of the reliability and the size of the system. This article proposes a peak and valley current control for Cuk PFC converter to remove the bulky electrolytic capacitor. The proposed control is realized by a combination of analog and digital circuits. The analog circuits are used to accomplish the real-time comparison between the actual currents and their reference values. And the digital circuits are employed to deal with simple logical judgement. Different from the existing full digital control technique, which needs a high-quality digital signal processor (DSP) to process complex arithmetic operation, the proposed control concept even can only require a low performance microcontroller unit. Besides, the control delay is avoided. This article first analyzes the operation stages of the Cuk PFC converter. Then, design considerations of main circuit and control circuit are introduced. Finally, the experimental results from 200W Cuk PFC converter are presented to verify the effectiveness of the proposed control.

Amplitude Sampled Reference-Based Space Vector Pulse Width Modulation for Control of Voltage Source Converters

Memory, speed, reliability, and efficiency are the main characteristics of concern in new contemporary control techniques of electric power converters. Space vector pulse width modulation (SVPWM) is a widespread digital compute-intensive control technique used in the control of power converters. This study aims to overcome the large number of calculations needed by the SVPWM algorithm, which limits its implementation in many advanced industrial applications. This paper presents a low-cost software implemented simplified SVPWM technique. The proposed strategy generates the inverter switching times in a straightforward manner with no need for complicated and time-consuming sector identification and look-up switching tables. A simulation study has been done using MATLAB/SIMULINK environment for the three-phase voltage source converter (VSC). The results in terms of total harmonic distortion (THD) in the converter line voltage are compared for the proposed technique, conventional SVPWM, and space pulse width modulation (SPWM). The execution time is reduced considerably with a slight increase in the value of THD and about 14.4 percent DC-link voltage utilization over the SPWM.

Hardware-in-the-Loop and Digital Control Techniques Applied to Single-Phase PFC Converters

Power electronic converters for power factor correction (PFC) play a key role in single-phase electrical power systems, ensuring that the line current waveform complies with the applicable standards and grid codes while regulating the DC voltage. Its verification implies significant complexity and cost, since it requires long simulations to verify its behavior, for around hundreds of milliseconds. The development and test of the controller include nominal, abnormal and fault conditions in which the equipment could be damaged. Hardware-in-the-loop (HIL) is a cost-effective technique that allows the power converter to be replaced by a real-time simulation model, avoiding building prototypes in the early stages for the development and validation of the controller. However, the performance-vs-cost trade-off associated with HIL techniques depends on the mathematical models used for replicating the power converter, the load and the electrical grid, as well as the hardware platform chosen to build it, e.g., microprocessor or FPGA, and the required number of channels and I/O types to test the system. This work reviews state-of-the-art HIL techniques and digital control techniques for single-phase PFC converters.

Automation of the Leonardo da Vinci Machines

Leonardo da Vinci inventions and projects represent an intriguing starting point to remark the concept that innovation must be considered as a continuous route towards evolution in history. Some of the particular ideas and innovations presented by Leonardo da Vinci led us to formulate a link with automatic control. Selected models of the Leonardo da Vinci machines are presented in this paper, taking strictly into account the original mechanical schemes and working principles, but introducing modern low-cost control equipment, emphasizing the role of automatic control and that of electronic control devices, such as microcontrollers, sensors, and communication devices, to completely automate the Leonardo da Vinci machines. The approach outlined in the paper can be applied not only to other Leonardo machines but also to other mechanical equipment not necessarily designed by Leonardo da Vinci. Moreover, it is useful to remark that the approach followed in this paper can be very important also to introduce students, leading by example, to concepts typical of automation and for assisting in learning, keeping in mind the practical applications of advanced automation principles. The main research task of this paper is proving the efficacy of modern digital control techniques and teleoperation in strongly classical mechanical Leonardo machines, remarking that the projects of Leonardo are prompt to be efficiently controlled. This task could not be explored by Leonardo himself due to the lack of control technology. Moreover, the paper is addressed also to stimulate the young generations of engineers in joining classical mechanics with advanced technology. Therefore, the paper is also devoted to give focus on the fact that the Leonardo machines encompass all the key aspects of modern system engineering.

Development of a novel rotary flow control valve with an electronic actuator and a pressure compensator valve for a gas turbine engine fuel control system

This paper presents a new rotary proportional flow control valve with Cam-Nozzle configuration. The rotating cam against the fixed nozzle changes the flow area and then can meter the fuel flow. This valve equipped with a pressure compensator plunger type valve to retaining constant pressure difference across the flow control or metering valve. The cam shaft directly coupled to an electronic servomotor type rotary actuator and then it is possible to apply digital control techniques such as pulse width modulation (PWM) in this control system. This new valve configuration is developed for an electro hydro mechanical fuel control system in a gas turbine engine. In addition to aero engine application, this type of flow metering valve can widely be used in industrial hydraulic systems. In this unit, the output flow is proportional to the cam's angular position (or throttle command) and it is not sensitive to pressure fluctuations at nozzle inlet and outlet. The aim of this new design is to modify a manual single adjusted hydro-pneumatic fuel control unit to obtain a new electro-hydraulic fuel control system for a gas turbine engine. The main innovations in the presented fuel metering unit include new design of the rotary valve opening shape (Cam-Nozzle) without metal to metal contact, use of a rotary electronic actuating mechanism and also direct coupling between the actuator and the rotating cam. The increased fuel metering precision in the new flow control valve has improved the ultimate control accuracy of system. A computer simulation software based on the proposed model, is performed to predict the steady state and transient performance and to analyze effect of important design parameters on valve outlet fuel flow and obtain the final design parameters. The validity of the proposed valve configuration is assessed experimentally in the steady state and transient modes of operation. The results show good agreement between simulation and experimental in both modes (max. 4% deviation).

Multi-Resonant Indirect Digital Current Control Technique for Single-Phase Shunt Active Power Filters

This article proposes multi-resonant indirect digital current control technique for single-phase shunt active power filters. The main advantages of the suggested technique are simplicity, fast dynamics, low computational burden, and low current ripple. A straightforward design technique in the frequency domain is proposed to properly decide the controller gains and study its performance. Then, the digital implementation of the proposed control algorithm is presented, which lets implement it on a mid-range digital signal controller. Simulation and experimental results on a prototype system are reported to demonstrate the effectiveness of the proposed control system.

A Digital Pulse Train Controlled High Power Factor DCM Boost PFC Converter Over a Universal Input Voltage Range

In this paper, a digital-based pulse train (PT) control technique for a boost power factor correction (PFC) converter operating in a discontinuous conduction mode (DCM) is presented, which can achieve nearly unity power factor (PF) over a universal input voltage range. Different from traditional digital control techniques, which usually require complex arithmetic operations, the digital-based PT control technique only needs a simple operation. Besides, a DCM boost PFC converter with digital PT control can operate at a high switching frequency, which is less dependent on the processing speed of a digital controller. Thus, the proposed control strategy can be implemented with general purpose digital controllers, such as low-speed and low-cost microcontroller unit, for the DCM boost PFC converter where the cost is a focus. The operation principle of the digital PT controlled DCM boost PFC converter is analyzed. Experimental results are provided, which show that high PF and low input current total harmonic distortion can be maintained over a universal input voltage range of 90–264 V ac.

Digital space vector modulation decoupled control scheme grid connected 1-Ø riven bias inverter to suppress high-frequency current commutation

A single-juncture topology of 3-Ø boost inverter with riven DC supply configuration grieves from larger incidence current commutations across the diodepassive in connection with the DC source and the intricate study as the inductor charges with capricious duty cycle. This study focuses on 1-Ø riven bias inverter with improvised technique on inverter and modulation. The riven bias inverter is analyzed using state space averaging technique to derive the mathematical model that is suitable for both steady-state and dynamic behavior conditions considering main converter nonlinearities. Hence, the research is carry forwarded in modeling the riven bias inverter on DC section with digital space vector modulation control technique to obtain decoupled control structure in lattice network and the work is validated by means of MATLAB/SIMULINK.

Digital Control Techniques Based on Voltage Source Inverters in Renewable Energy Applications: A Review

In the modern era, distributed generation is considered as an alternative source for power generation. Especially, need of the time is to provide the three-phase loads with smooth sinusoidal voltages having fixed frequency and amplitude. A common solution is the integration of power electronics converters in the systems for connecting distributed generation systems to the stand-alone loads. Thus, the presence of suitable control techniques, in the power electronic converters, for robust stability, abrupt response, optimal tracking ability and error eradication are inevitable. A comprehensive review based on design, analysis, validation of the most suitable digital control techniques and the options available for the researchers for improving the power quality is presented in this paper with their pros and cons. Comparisons based on the cost, schemes, performance, modulation techniques and coordinates system are also presented. Finally, the paper describes the performance evaluation of the control schemes on a voltage source inverter (VSI) and proposes the different aspects to be considered for selecting a power electronics inverter topology, reference frames, filters, as well as control strategy.

A Digital Current Control Technique for Grid-Connected AC/DC Converters Used for Energy Storage Systems

This paper presents an advanced current controller for grid-connected bidirectional ac/dc converters used for energy storage systems (ESSs). The proposed control scheme is designed to incorporate both the time-domain and frequency-domain dynamics to achieve superior transient and steady-state performance. The advanced current controller can overcome the various challenges faced by the conventional current controllers used in this application, which lead to sluggish transients and steady-state errors when tracking the sinusoidal reference for the grid current. Combining the time-domain dynamics with the frequency-domain dynamics creates a more intelligent controller compared to existing methods, which only consider the dynamics of one domain. The proposed controller is able to eliminate steady-state error by adaptively changing the controller coefficients in the frequency domain according to the current error. In the time domain, the control scheme minimizes the derivative of a defined energy function in order to optimize the transient performance. Simulation and experimental results obtained from a 3.3-kW grid-connected ac/dc converter demonstrate its superior performance.

A Novel Interface Circuit with 99.2% MPPT Accuracy and 1.3% THD for Energy Harvesting

To improve conversion efficiency and output quality of the energy harvester, a novel interface circuit with composite maximum power point tracking (MPPT) in energy harvesting applications is proposed in this paper. By using the ultra-low-voltage multiplier with digital control and simple one-cycle variable frequency technique, the converter realizes fast power tracking and high conversion efficiency, and minimizes the power consumption and harmonics, thereby obtaining high tracking precise and low total harmonic distortion (THD). Implemented in 65-nm CMOS process, this converter achieves 85.9% peak power efficiency with dc output voltage of 1.6[Formula: see text]V. The peak tracking efficiency and THD are 99.2% and 1.3%, respectively. The peak output power is 18.31[Formula: see text][Formula: see text]W, and the power loss of the entire converter is only 16.53[Formula: see text][Formula: see text]W.

Multi-resonant piezoelectric shunting induced by digital controllers for subwavelength elastic wave attenuation in smart metamaterial

Instead of analog electronic circuits and components, digital controllers that are capable of active multi-resonant piezoelectric shunting are applied to elastic metamaterials integrated with piezoelectric patches. Thanks to recently introduced digital control techniques, shunting strategies are possible now with transfer functions that can hardly be realized with analog circuits. As an example, the ‘pole-zero’ method is developed to design single- or multi-resonant bandgaps by adjusting poles and zeros in the transfer function of piezoelectric shunting directly. Large simultaneous attenuations in up to three frequency bands at deep subwavelength scale (with normalized frequency as low as 0.077) are achieved. The underlying physical mechanism is attributable to the negative group velocity of the flexural wave within bandgaps. As digital controllers can be readily adapted via wireless broadcasting, the bandgaps can be tuned easily unlike the electric components in analog shunting circuits, which must be tuned one by one manually. The theoretical results are verified experimentally with the measured vibration transmission properties, where large insulations of up to 20 dB in low-frequency ranges are observed.

Power quality enhancement of single phase grid tied inverters with model predictive current controller

Recognition of renewable energy sources as alternative sources for power generation has augmented the number of distributed generation plants being incorporated into the conventional power distribution system. The single phase voltage source inverter allying the distributed generation plant with the grid has to address various issues related to the quality of current injected into the grid, output power factor, and power exchange between the plant and the grid. This paper focuses on the analysis, design, and implementation of a digital predictive current control technique known as model predictive current controller for the control of single phase power inverter integrating renewable energy based plant with the grid. The proposed controller is tested in diverse operating conditions and is compared with the existing proportional resonant current control scheme. The simulation and experimental results validate the efficacy of the proposed control technique.