Performance Of Rectifier Research Articles

Enhanced performance of electric vehicle Vienna rectifier through soft computing and sliding mode control

Enhanced performance of electric vehicle Vienna rectifier through soft computing and sliding mode control

Ultra-Low On-Resistance W/β-Ga2O3 Junction Barrier Schottky Rectifiers

The on-resistance of Ga2O3 rectifiers with different metal anodes was measured from the forward current-voltage characteristics. The use of W anode metal produces low on-resistance of 0.34 mΩ.cm2 for W/Au/ β-Ga2O3 Schottky Barrier Diode (SBD) rectifiers and 0.22 mΩ.cm2 for heterojunction Diode (HJD) NiO/β-Ga2O3 rectifiers, overcoming the generally much larger values obtained using Ni or Pt metal. These are the lowest on-resistances reported for Ga2O3 rectifiers. The turn-on voltage was 0.22 V for SBD and 1.69 V for HJDs. By changing the anode metal, we varied the effective barrier height, which also affects reverse breakdown voltage. The switching characteristics were measured for the different device types, with reverse recovery times of 30.6 ns for SBDs and 33.0 ns for HJDs and slew rates of 2 A.μs−1 for both types of devices. Using a simple change of anode metal allows the achievement of a broad range of breakdown voltage and on-resistance, which allows for tailoring the rectifier performance depending on the application.

High rectification effects of heterojunctions based on C3N4 nanoribbons

Two heterojunctions based on zigzag graphitic carbon nitride nanoribbons (ZCNNRs), namely, BnAn and CnAn, are considered and their electronic transport properties are studied using the nonequilibrium Green's function (NEGF) in combination with the density functional theory (DFT). The BnAn is formed by the joining of bare and partially hydrogenated ZCNNRs. The CnAn is created by the attachment of bare and fully hydrogenated ZCNNRs which leads to a Schottky barrier. The results show that current–voltage characteristics (I–V) can be significantly tuned by the length variation of heterojunctions. Furthermore, it is found that both heterojunctions have a remarkable nonlinear behavior in the whole bias range. The B4A4, B3A4, and B4A3 have forward rectifier performance whereas B2A2, B3A3, C2A2, C3A3, C4A4, C3A4, C4A3, C5A3, and C6A3 show the reverse rectification behavior. In the case of BnAn, the maximum rectification ratio (RR) of B4A4 is boosted up to 3.97 × 107 at 0.4 V. Additionally, for CnAn, the maximum RR of C4A3 can reach 1.37 × 105 at 1.0 V. Our investigation reveals that the BnAn heterojunction has negative differential resistance (NDR) under positive bias.The peculiar transport behaviors of B4A4 and C4A3 are explained due to the energy level shifts of electrodes with applied bias voltage and great alterations in the transmission spectrum. Furthermore, the Molecular projected self-consistent Hamiltonian (MPSH) and projected local density of states (PLDOS) are analyzed for these devices. The findings of this work reveal unique opportunities to design the ZCNNRs nanoelectronic devices.

Back Propagation Artificial Neural Network Based DC Bus Capacitance Identification Method in Three-Phase PWM Rectifier for Charging System of EVs

In order to improve the performance and reliability of the three-phase PWM rectifier in electric vehicle (EV) charging system, it is important to focus on the identification of the DC bus capacitance. The existing methods have the disadvantages such as a low identification accuracy, a high hardware dependency, and high costs. Therefore, the development of new identification methodologies could be the way out of the aforementioned disadvantages, in terms of advanced algorithms. In this paper, a DC bus capacitance identification method based on back propagation (BP) artificial neural network (ANN) algorithm is proposed. The capacitance can be accurately identified in the diode rectification stage, by training the neural network to extract the potential laws in the data, which only includes the Phase-a voltage and current, as well as the DC bus voltage ripple. The regression response is 0.99991. Finally, the experimental results show the accuracy and effectiveness of the proposed method. A simple and effective BP ANN is designed, and it can identify the capacitance at different grid voltages and DC bus loads. It has a high identification accuracy that the maximum identification error is less than 4.5%.

Comparative Analysis of a Rectifier Performance in Power Generation Applications

Electrical energy's significance is critical to human life, as seen by the rising usage of this resource. Electricity-consuming machinery and technology are developing at an accelerating rate. A substantial electrical power supply is required to achieve these requirements. An effective method to address this issue is to use a generator set powered by an electric motor. This generator necessitates the use of a converter, which serves the purpose of transforming alternating waves (AC) into direct waves (DC), generally referred to as a rectifier. The rectifier's unsatisfactory performance necessitates the need for this research, which seeks to develop and construct a rectifier and subsequently compare its performance utilizing two distinct current sources. Rectifier performance is obtained through the utilization of direct computation and measuring methods. Two sources charge the battery: direct current from the motor and alternating current from the power grid. According to the test results, the converter using an electric power plant source had a higher current value. On the generator, the battery charges up to 13.4 volts in 55 minutes, which is 5 minutes quicker than on the PLN source.

Optimization of Single-phase PWM Rectifier Performance by Using the Genetic Algorithm

This paper is dealing with single phase PWM rectifier parameter optimization. A control loop has been designed to attain a suitable output DC voltage with minimum ripple, input current with minimum harmonic and maximum input power factor. In this paper these parameters have been optimized by using Genetic algorithm. To verify the effectiveness of proposed optimization, different simulations have been done. By using MATLAB simulink the simulation results prove that the proposed system working good.

Performance Analysis of Direct Power Controlled PWM Rectifier under Disturbed AC Line Voltage.

Voltage and current source inverter are widely used in electrical motor drives. In this drives, DC voltage (or current) are usually provided from phase control or line commutation rectifiers. Because of disadvantage & limitation of this converter, some new topologies are presented in advanced drive such as PWM rectifier. Thanks to well known capabilities of PWM rectifier, classical converter’s problem can be overcome. There are several PWM rectifier control strategies. In this paper these control methods are introduced. At first, performance of the Direct Power Control (DPC) PWM rectifier is studied under balanced voltage condition. As line voltage disturbance are often considerable in industrial applications, rectifier performance under disturbed line voltage is investigated. For this purpose a DPC method is implemented in MATLAB/SIMULINK environment. Based on simulation results, DPC-PWM rectifier performances under unbalance and voltage sag is discussed.

Voltage and Current Sensor Fault Diagnosis Method for Traction Rectifier in High-Speed Trains

The traction rectifier plays a key role in high-speed trains. Unexpected failure often occurs in the sensors of the rectifier, which may affect the control performance of the electric traction rectifier and even cause serious deterioration to high-speed trains. A sensor fault diagnosis method is presented in this paper, considering three kinds of common fault types. It can not only locate the sensor fault, but also identify fault types. Based on the influences of the sensor faults, the fault diagnosis thresholds can be calculated quantitatively. No additional hardware is required. First, the model of the rectifier is established, and the estimator is built. The current residuals with different faults can be obtained. Next, residuals are analyzed and features are acquired. Then, diagnosis functions are constructed, which are used for fault location and fault type identification. Finally, the feasibility and effectiveness of the method have been confirmed by the experimental results.

Preliminary design of an OWC wave energy converter battery charger

This paper introduces a low-power off-grid oscillating water column wave energy converter with an internal battery bank. The research aims at the preliminary design and devising of the control strategy of a power electronics interface between the turbo generator and the battery bank. The converter comprises a spar buoy, a biradial turbine, a permanent magnet generator, a full-wave bridge rectifier, a braking chopper, a DC-to-DC step-down converter, and a lead-acid battery bank. The power-take-off system was modelled in Simulink/MATLAB, and its performance was assessed with steady-state simulations, considering a wave climate characteristic of Leixões, Portugal. The chamber pressure, the turbine, generator and rectifier performance were taken from experimental data sets. A simple battery model was derived from the manufacturer's datasheet. An ideal step-down DC-to-DC converter operating in discontinuous conduction mode regulates the battery charging current. This converter, in parallel with the braking chopper, adjusts the generator counter torque by regulating the current through the rectifier. Twelve system variables were recorded for selected pairs of input pressure and step-down converter design coefficient. The power at the rectifier's output terminals was mapped for the rotational speed and input pressure. The results show a system rating of 1.4 kW with 400 W of electrical power at 200 rad/s for the most frequent sea states. The range of the duty cycle, the inductance and the braking resistance were derived. Two closed-loop controllers were proposed for managing the step-down converter and the braking chopper. Their set points and saturation limits were derived from the simulation results.

Dynamic Performance Improvement of Wound Rotor Synchronous Starter/Generator System Based on PWM Rectifier

This paper proposes an active field current tracking (AFCT) control strategy for pulse width modulation (PWM) rectifier, which can remarkably enhance the system’s dynamic performance of wound rotor synchronous starter/generator (WRSSG) system when the load changes. WRSSG system uses a PWM converter in the aero-engine starting process and can reuse the power circuit as a PWM rectifier for high-voltage direct current (HVDC) power generation, thus simplifying the system structure, volume, and weight. The mathematic model of WRSSG system with PWM rectifier is introduced. Based on the system model, the PI controller of armature current loop is designed. The nonlinear PI controller of excitation voltage loop is also illustrated. A 15kW WRSSG system based on PWM rectifier is implemented. The AFCT control strategy and its high dynamic performance are verified by experiments. The simple system structure and distinguished dynamic performance of PWM rectifier with AFCT control can make the WRSSG system more competitive in aircraft applications.

Near-field thermal rectification via an InSb/graphene/3C–SiC-nanowire heterostructure

Thermal rectifiers allow asymmetric heat flux when the temperature bias between two terminals is reversed. Based on the near-field radiative heat transfer, the performance of thermal rectifiers can be significantly enhanced. Here, we propose a near-field thermal rectifier based on the InSb/graphene/3C–SiC-nanowire heterostructure. The rectifier consists of two terminals, one terminal is an InSb slab with a graphene-coated bottom, and the other terminal is a 3C–SiC nanowire array with a graphene cover on its top. By using fluctuational electrodynamics, we calculate the radiation heat flux and the corresponding thermal rectification efficiency (TRE). The results show that the strong asymmetric surface plasmon polaritons (SPPs) and hyperbolic phonon polaritons (HPPs) in the forward and reverse heat transfer scenarios guarantee a robust TRE. Besides, the TRE of the proposed heterostructure can be dynamically controlled and optimized via the chemical potential of graphene, the volumetric filling ratio of the nanowire array, and the terminal temperature. Specifically, the thermal rectification efficiency (1 – min (Qf, Qr)/max (Qf, Qr) with Qf and Qr denoting the forward and reverse heat flux, respectively) can exceed 80% at a wide-ranged terminal gap and reaches a maximum of 92.96%.

Passivity-Based Control and Current Balance Control of a Current-Source Pulse-Width-Modulation Rectifier

To improve the static performance, dynamic performance, and current balance of a current-source PWM rectifier with multi-modules, a comprehensive control method with passivity-based control and current balance control is proposed in this paper. Current balance control, which is based on AC voltage sequencing, has the advantages of being easy to implement and not being limited by the number of modules. Mathematical modelling, controller design, and simulation verification were conducted successively, and the results show that the comprehensive control method has a low current impact and high power quality. At the same time, module currents are well balanced, even under external disturbance, when using current balance control.

Compact and Efficient Dual-Band Rectifier Using Modified T-Section Matching Network

In this letter, a compact and efficient dual-band rectifier for radio frequency (RF) energy harvesting is presented. The proposed design utilizes a modified T-section comprising a parallel resonance circuit combination of LC in the shunt arm, which plays a key role in obtaining the resultant dual-band rectifier. The shunt arm provides a shift of the high-frequency point in the clockwise direction on the impedance trace (Smith chart) while maintaining an insignificant shift at the lower frequency. The proposed design is verified through theoretical and simulation studies for different Schottky diodes. The circuit is optimized and fabricated to compensate for undesired parasitic effects and achieve the required rectifier performance. For validation, a dual-band rectifier working at 1.4 and 2.45 GHz is fabricated. The measured results show that with a 3.02 k <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $</tex-math> </inline-formula> load, the maximum efficiencies of the rectifier achieve 65.0% and 57.0% at 1.4 and 2.45 GHz, respectively with 0 dBm input power.

An Improved Multi-Pulse Rectifier Circuit for Input Current Harmonic Suppression Using Passive Devices

Renewable energy resources, such as solar and wind, are increasingly being integrated into power systems to promote sustainable and clean energy generation. However, the intermittent nature of these resources poses challenges in terms of harmonics, power factor and power quality. This paper focuses on the use of multi-pulse rectifiers (MPR) as a solution for enhancing the performance and grid integration of renewable energy resources. A novel approach is introduced, combining a phase-shifting transformer that provides a five-phase input to a series of 20-pulse rectifiers with a pulse-tripling circuit (PPTC). By modulating the resultant currents of bridge rectifiers with PPTC, the rectifier’s pulse number is raised from 20 to 60, resulting in enhanced reduction of input current harmonics. The proposed rectifier configuration achieves an input current with an approximate sinusoidal waveform, exhibiting a Total Harmonic Distortion (THD) of less than 4%. The proposed scheme offers several advantages. It is simple, utilizing only passive components without the need for active devices, making it easy to implement, improving the performance of rectifier, ensuring compliance with power quality standards, and enabling reliable operation in medium- and high-voltage electronic systems.

A multi-level rectifier with voltage balancing capability for EV charging

ABSTRACT In two-stage electric vehicle (EV) battery chargers, ac-dc conversion stage contributes significantly in determining the power quality. At this stage, multilevel rectifiers (MLRs) featuring switches with lower voltage rating and better input voltage waveform quality can be adopted. However, balancing capacitor voltage in MLR is an important challenge. In this paper, a single-phase five-level power factor correction (PFC) rectifier with self-balancing capacitor is implemented for EV battery charging. The complimentary switching scheme adopted for rectifier reduces number of gate driver circuits and ensures capacitor voltage balancing. The rectifier shows added benefit of reduced voltage stress across switches and not requiring an external filter at the dc side as the load is parallelly connected with one of the capacitors. The operating principle, control strategy, modulation technique and design features of the implemented five-level rectifier is discussed in detail. The implemented control scheme enhances rectifier performance by establishing precise output voltage regulation during load fluctuations while maintaining unity power factor at input side. The five-level rectifier is validated experimentally and compared with other existing multilevel and non-multilevel rectifier topologies. The peak efficiency of 93.8% is achieved at 2 kW of output power.

IMPROVED ACTIVE FILTER PERFORMANCE IN SINGLE-PHASE CONTROLLED RECTIFIERS WITH PULSE WIDTH MODULATION (PWM) CONTROL

Various commutation techniques, such as forced commutation, ignition angle control, and symmetrical angle control, have been developed to improve the input power factor and harmonic level. However, all of these techniques will produce only one pulse per half cycle of the converter input current, and consequently, the lowest order harmonic is the third harmonic. A comparative study of active filter converters between single pulse and PWM control has been investigated. Both converters are given identical R and RL loads to compare power factor (PF) and Total Harmonic Distortion (THD). The method used is a simulation with the PSPICE program. The performance of both rectifiers is evaluated based on the input current waveform, THD, and PF. At RL load, the input current distortion decreases drastically, with a THD of 100.67%. In PWM control, harmonics are reduced with a THD of 25.48%. The rectifier power factor in the active filter obtained PF of 0.25, whereas in PWM control, PF increased by 0.65.

Efficient single and broadband microwave rectifiers for RFEH/WPT enabled low power 5G sub-6 GHz devices

In recent years, the enormous innovation in the wireless system has escalated the demands of fifth-Generation (5G) enabled RF Energy Harvesting (RFEH) and Wireless Power Transfer (WPT) systems. With this motivation, the proposed work introduces two efficient rectifier configurations for potential implementation in both RFEH and WPT systems covering global Sub-6 GHz 5G bands. The Design-1 presents a single-band rectifier covering 3.3–3.7 GHz sub-6 GHz 5G band. A dual Transmission Line (TL) based Matching Network (MN) is used to improve the rectifier performance. At 0 dBm, Design-1 achieved maximum Power Conversion Efficiency (PCE) of 76 % at 3.5 GHz and 4kΩ load. The Design-2 presents a 3.3–5 GHz broadband rectifier circuit that covers the entire sub-6 GHz 5G bands. A MN based on multi-stepped TL is used to improve the rectifier performance for the broad frequency band and achieved a PCE greater than 35 % and 50 % at 0 and 9 dBm, respectively at a load value of 1kΩ. For validation, prototypes of both rectifiers are fabricated and a very good agreement between simulated and measured results is achieved. The proposed rectifier configurations hold immense potential for implementation across nations and offer a global solution to self-sustainable low-powered 5G battery-less devices.

Advanced Control of Three-Phase PWM Rectifier Using Interval Type-2 Fuzzy Neural Network Optimized by Modified Golden Sine Algorithm

Three-phase Pulse-Width Modulated (PWM) rectifiers used between the power grid and the load in applications requiring DC voltage have features such as high efficiency, high power factor, and low harmonics. This paper proposes a hybrid control approach to improve the dynamic performance of three-phase PWM rectifiers under different operating conditions. Operating conditions are considered as step response, internal disturbance, and regenerative operation. First, Interval Type-2 Fuzzy Neural Network (IT2FNN) is designed and then antecedent and consequent parameters of IT2FNN are optimized with Modified Golden Sine Algorithm (GoldSA-II). The dynamic performance of the hybrid controller, named GoldSA-II-IT2FNN, is analyzed for all operating conditions in Matlab/Simulink environment. The simulation studies are realized to evaluate the performance of the proposed controller. In the simulations, settling times of proposed controller are observed as 27.2 ms, and 10.8 ms for step response, respectively. Moreover, recovery times are calculated as being 12 ms to 5.5 ms for internal disturbance, and 7.2 ms to 19 ms for regenerative operation, respectively. The obtained results demonstrate that the proposed controller not only provides better dynamic performance but also improves the stability of PWM rectifier.

Study of the Aerodynamic Performance of Pantograph Bowhead with Serrated Lower Surface in the Thermal Management Systems of the High-Speed Train Electrical Devices

The thermal management problems of traction drive systems for high-speed trains are of great importance for the operation reliability of high-speed trains. The thermal performance of transformer and traction rectifier are mainly affected by the aerodynamic performance of pantograph. Nine bowheads with different sawtooth structures on the lower surface are proposed and a CFD numerical model is built with Transition SST turbulence model. The influence of the number and height of sawteeth on the aerodynamic characteristics of the bowhead flow field are investigated. The results show that compared with the rectangular bowhead, the aerodynamic drag of the 5w3h-shaped bowhead is reduced by 8.6%, 8.7%, and 9.9% at train speeds of 250 km/h, 300 km/h, and 350 km/h, respectively. The promotion of aerodynamic performance of pantograph is beneficial to improve the thermal characteristics of traction drive systems for high-speed trains.

A Novel Graphical Approach for the Fast Estimation of Filter Capacitor Value and the Output Performance of Various Uncontrolled Rectifier

This paper proposes a novel approach for low-power applications for the fast estimation of filter capacitor value and the output performance parameters such as average, and Root Mean Square (RMS) values for the voltage and current considering single-phase full-wave, three-phase half-wave and three-phase full-wave rectifier circuits. For this aim, the novel equations in this work are derived for the average output voltage and rms ripple voltage separately for each of the above-mentioned three rectifier types. Then % ripple factors for each rectifier type are calculated using newly derived equations and plotted versus the newly introduced Normalized Time Constant (NTC). Besides, considering the peak supply voltage as the base voltage, the Per Unit (p.u.) output average voltage and rms ripple voltage for each of the rectifier circuits are computed and plotted versus NTC. These graphs will be normalized graphs since the output values of these graphs have turned into independent of both supply voltage amplitude and supply frequency. Normalized graphs are set up only once for each type of the rectifier circuit. Then, and for a pre-selected ripple factor value, the corresponding NTC value is obtained by straightforward reading from the graphs set up between the % ripple factor and NTC. Once the NTC value has been acquired, using the formula of NTC leads to finding the capacitor value required for the pre-selected ripple factor with one simple step calculation. Furthermore, the p.u. values of the average output voltage and rms ripple voltage values that correspond to the same NTC value are obtained by reading them from the set-up graphs directly. Finally, the efficiency of the proposed method is demonstrated through design examples for each type of rectifier circuit. The three design examples highlight how the output performance values can be obtained easily, accurately and swiftly. Furthermore, the viability of the graphical approach is verified by the experimental results which demonstrate the suitability of the derived equations in the proposed method.