Switch-mode Rectifier Research Articles

A single current sensor based adaptive step size MPPT control of a small scale variable speed wind energy conversion system

Due to the limited size and lower environmental impact, a small-scale wind energy conversion system (WECS) is a promising alternative for remote locations and residential areas where installing large wind turbines is not feasible. This system employs a permanent magnet synchronous generator (PMSG) as a variable speed wind generator due to its advantages such as high torque density, gearless, and require no external excitation, etc. This article proposes a single load current sensor-based adaptive step size (LCAS) maximum power point extraction (MPPT) method which utilizes the load current information to track the maximum power. This method does not require rotor speed information and knowledge of the turbine parameters. Also, this article uses a simple and cost-effective switch mode rectifier topology (AC–DC and DC–DC boost converters) for the PMSG-based variable speed WECS. The proposed method is validated in a 1.5 kW test rig using an OPAL-RT digital signal controller and also compared with various fixed step size (FSS) MPPT algorithms at various operating conditions. Extensive experimental work has been carried out for the LCAS MPPT method that confirms the tracking efficiency is better and tracking speed is faster along with the improved steady state as well as transient performance.

Measured and estimated wind speed of a stand-alone energy system with controlled bi-directional DC-DC battery bank

Simple control of a stand-alone variable speed wind turbine with a permanent magnet synchronous generator (PMSG) is presented in this paper. PMSG fed different types of loads by means of a converter where switched mode rectifier is connected to the PMSG, boost DC-DC converter, and voltage source inverter (VSI). The wind turbine is operated at measured wind speed and it is tested at estimated wind speed which is based on the power calculation of turbine power, generating electric power, losses power, and the dynamic power during the variation of wind speed. The estimation of wind speed would provide a scope of what a control method is applicable in practice and this would increase the performance by scheduling the connected loads. The bidirectional battery charger is controlled and used during the shortage of wind speed. The converter of the battery charger is controlled and implemented on an embedded system by using an STM32-based microcontroller. During the shortage or fluctuation of wind speed, the load voltage is controlled within the acceptable limit, where the voltage has been compensated. An extensive simulation has been conducted by MATLAB/Simulink, and the system shows a good dynamic response to the variation and decrease in wind speed.

Wind SRG-Based Bipolar DC Microgrid with Grid-Connected and Plug-In Energy Supporting Functions

Although a switched reluctance generator (SRG) is not the mainstream wind generator, it possesses the application potential and is worth developing for its many structural merits and high developed power ability. This paper presents a wind SRG-based bipolar DC microgrid having grid-connected and plug-in energy supporting functions. First, a surface-mounted permanent magnet synchronous motor (SPMSM)-driven wind turbine emulator (WTE) is established. Next, the wind SRG with an asymmetric bridge converter is developed. Good generating characteristics are obtained through proper designs of power circuit, commutation mechanism, external excitation source, voltage and current controllers. Third, a DC/DC boost interface converter and a bipolar voltage balancer are constructed to establish the 500 V microgrid bipolar DC-bus. To preserve the microgrid power supplying quality, a battery energy storage system (BESS) with bidirectional DC/DC interface converter is equipped. A dump load leg is added across the bus to limit the DC-bus voltage under energy surplus condition. In load side, a three-phase bidirectional load inverter is developed, which can be operated as a single-phase three-wire (1P3W) inverter or a three-phase three-wire (3P3W) inverter. Good sinusoidal voltage waveform and regulation characteristics are obtained using the proportional-resonant (PR) control. The microgrid to load and microgrid to grid operations are conductible. Finally, to further improve the powering reliability of microgrid, a three-phase T-type Vienna switch-mode rectifier (SMR) based plug-in energy supporting scheme is developed. When the microgrid energy shortage occurs, the possible harvested energy can be used to supply the microgrid.

Development of an Aircraft Electric Power Architecture With Integrated Ground Power Unit

This article presents a switch-mode rectifier-based electric power architecture with an integrated ground power unit for more electric aircraft. The well-regulated high-voltage dc-bus is established from the aircraft generator. And the conventional major 270-Vdc, 28-Vdc, and 115-Vac/400-Hz buses are also preserved. In landed conditions, the ground power unit function powered by the mains is inherently possessed thanks to the proposed integrated schematic. First, the developed switch-mode rectifier using a silicon-carbide device with a wide frequency range covering utility line frequency and aircraft generated varied high frequency is presented. The allowable energy storage inductances using the embedded generator armature winding are derived. Good generator armature power quality and well-regulated dc output voltage are preserved by the designed current and voltage control schemes. Next, the utility grid-powered ground power unit established by the embedded schematic is introduced. Finally, the inverter for generating the 115-Vac/400-Hz three-phase source and the dc–dc converter for establishing the 270-Vdc bus are constructed. Normal operations, good dynamic, and steady-state performances of all the constructed power stages are verified experimentally, which can confirm the feasibility of the proposed aircraft power architecture.

MAXIMUM POWER COEFFICIENT CONTROL OF A MICRO GRID-CONNECTED WIND ENERGY SYSTEM

This paper proposed the integration of the wind energy system (WES) with the grid consists of a wind turbine, a permanent magnet synchronous generator (PMSG), a switch-mode rectifier (SMR) and a three-phase voltage source inverter (VSI). Optimal torque control (OTC) method is applied to the converter on the generator side for maximizing the power coefficient under the change in wind speeds. To synchronize the WES with the grid, another controller is applied to keep dc-bus voltage at constant value and to regulate active and reactive power transmitted into a grid. A system of WES connected into a grid is created and tested in the MATLAB/SIMULINK platform version 2019b. Comprehensive simulation results are used to analyze and verify the excellent performance of the suggested two- control strategy on the machine and grid side.

On a SMR-Fed SynRM Drive With Real-Time Commutation Tuning

This paper presents a switch-mode rectifier (SMR) fed synchronous reluctance motor (SynRM) drive. Good driving performance over wide operating range is achieved via: (i) boosted and well-regulated DC-link voltage established by the SMR; (ii) real-time commutation angle tuning by the adaptive commutation scheme (ACS) using on-line fitted motor key parameters, and equivalently by the model-free intuitive commutation tuning (ICT) scheme; (iii) robust current control considering slotting harmonic effects; and (iv) quantitative and robust speed controls. First, the SynRM drive with fixed DC-link voltage is established. The real-time commutation tuning scheme with motor total loss minimization is proposed. Then the dynamic current and speed control schemes are designed. The feedback controllers are augmented with simple robust control schemes to have satisfactory responses. Under well-regulated DC-link voltage, good line drawn power quality is obtained simultaneously. Moreover, the regenerative braking power can be recovered back to the utility grid. Finally, the whole SMR-fed SynRM drive is evaluated. The motor driving characteristics under higher speeds and heavier loads are enhanced.

Phase-Variable Modeling and Comparative Study between a PMa-CPA and a CPA Alternator by Simulation Analysis

This paper presents the phase-variable modeling of a permanent magnet-assisted claw-pole alternator in PSIM simulation software tool with the performance compared with a claw-pole alternator model, which is a special case of the permanent magnet-assisted claw-pole alternator model with the rotor permanent-magnet flux constant setting equal to zero. The constructed model can be simulated as a real alternator directly connected to a diode-bridge rectifier or switch-mode rectifier circuit for the integrated power application system simulation analysis. The proposed model contains two features, one of which is that the stator and rotor windings are circuit-based. The other one feature is that the mechanical torque input is based on a mathematical function. In this model, the rotor position-dependent variable inductor is replaced by a separate voltage source according to the voltage source absorption theorem. The simulation shows that the proposed model has faster torque step response and higher power efficiency than the claw-pole alternator model. The proposed model can be employed to the application of the control design and simulation study of voltage regulation in automobiles. The simulation results with 15-V command and the load sudden change verify the correction of the proposed model.

Development of Wind IPMSG Based Bipolar DC Microgrids

This paper presents the development of a wind Interior Permanent-Magnet Synchronous Generator (IPMSG) based bipolar DC microgrids along with various switch-mode rectifiers. Firstly, the wind IPMSG is established and adequately controlled to possess satisfactory generating characteristics during different driven speeds and loads. Later, the boost switch-mode rectifier (SMR) based bipolar DC bus is established. Further, three-phase single-switch (3P1SW) boost SMR, three-phase two-switch (3P2SW) three-level boost SMR, and a three-phase three-switch (3P3SW) Vienna SMR are comparatively evaluated. Along with the proposed robust voltage and current controls, a well-regulated microgrid DC-bus voltage is established. Moreover, the voltage balancing control is proposed to minimize the imbalance in the bipolar DC-bus voltage. For the wind IPMSG having Vienna SMR, the commutation angle setting is adjusted to use the reluctance power component effectively.

A Switched-Reluctance Motor Drive Powered by Switch-Mode Rectifier with Battery Energy Storage Buffer

This paper presents a three-phase full-bridge boost switch-mode rectifier (SMR) powered switched-reluctance motor (SRM) drive with battery energy storage buffer. It covers the designing of the power circuits and control schemes for the two power stages. Except for having a superior line-drawn power quality, the boost-able DC-link voltage of the SRM drive can enhance the SRM driving performance in a wide speed range and sent back the recovered regenerative braking energy to the grid successfully. The next is establishing a battery energy storage system (BESS) with a bidirectional interface DC-DC converter connected to the motor drive DC-link for providing an energy buffer. The proposed parallel operation strategy has three possible inter-connected operations. (i) Grid-to-battery (G2B) charging: The battery charged by the grid with a good line drawn power quality. (ii) B2G discharging operation: The battery sending power back to the grid by the interface converter and the SMR. (iii) Battery buffer operation: Powering of the SRM drive simultaneously by the utility grid and the battery with the proposed parallel operation strategy.

A Wind Turbine Emulator Using Field-Oriented Induction Motor

This paper proposes a Wind Turbine Emulator (WTE) using an Indirect Field Oriented (IFO) Induction Motor (IM). The IM drive can be controlled as a conventional prime mover in speed mode, or a wind turbine in torque-speed mode via robust observed torque control. This paper presents key issues for establishing a high-performance IFO IM drive. Further, this study develops a wind turbine load Interior Permanent-Magnet Synchronous Generator (IPMSG) followed by a three-phase Vienna Switch-Mode Rectifier (SMR). It receives mechanical driven power from the WTE and establishes a 400V DC-link for the DC micro-grid. The good generating characteristics are achieved through proper controls of both the IPMSG and SMR. Various wind turbine torque-speed and power-speed characteristic curves under different wind speeds can be emulated by the developed WTE. The designed results are verified by simulations. The measured results indicate that the errors are within 1.5% and 1.0%, respectively, for the torque and the power compared to the designed ones. The maximum power point tracking (MPPT) function with good performance for the PMSG with Vienna SMR is achieved using the perturb and observation (P&O) approach. The dynamic and steady-state operating characteristics of the developed whole turbine emulator driven PMSG system are assessed experimentally.

Wind Switched-Reluctance Generator Based Microgrid With Integrated Plug-In Energy Support Mechanism

This article presents a wind switched-reluctance generator (SRG) based microgrid (MG) with plug-in energy support mechanism. First, the wind SRG is properly designed and controlled. By applying the dynamic commutation shift and robust voltage control, it has the generated voltage with fast tracking and regulation responses under varying driven speed and load. Then, the MG common dc-bus voltage is established via a reconfigurable interleaved boost converter. The working cell number can be automatically changed to possess high efficiencies over wide power range. To enhance the voltage regulating characteristics, the feedback controller is augmented with an adaptive command feedforward controller and a robust tracking error cancellation controller. A bidirectional Capacitor-inductor-inductor-capacitor (CLLC) resonant converter and a bidirectional single-phase three-wire (1P3W) load inverter are constructed for powering loads and conducting grid-connected operation. As the wind energy input is deficient and even the wind turbine is halted, the inherent SRG followed boost converter can be reconfigured to form an interleaved boost switch-mode rectifier. The possible harvested single-phase ac and dc sources can be plugged into the MG for achieving energy support. The operation characteristics of the MG and the smooth transfer between all constituted power stages are demonstrated experimentally.

Performance analysis of maximum power point tracking control system for standalone wind power system in Sittwe, Myanmar

One of the most feasible Renewable Energy resources of the World is wind energy. The performance of the Maximum Power Point Tracking (MPPT) control system for the operation of the Standalone Wind Power generation system is studied in this research. Sittwe, the capital of Rakhine State in Western Coastal Region, is the chosen case study area that enriches the Wind Energy resources in Myanmar with the low electrification rate. The proposed Standalone Wind Power generation system is composed of three-phase, 20kW Permanent Magnet Synchronous Generator (PMSG), DC-DC bidirectional converter, switch mode rectifier, voltage source inverter, and three-phase load. It is modelled and simulated in the MATLAB/Simulink. The simulation period is set to 15 seconds. Under Wind speed variation from 3 m/s to 13 m/s, the investigation is performed with the nexus of the speed, torque, power, DC link input, DC link output, and the parameters of the load side. In the simulation results, the power characteristics show the 20 kW standalone wind power system. It is observed that the output load voltage can be controlled by load side converter to required load voltage. In addition, the simulation results reflect the dynamic performance can be improved with the proposed MPPT control system.

Optimization of Power Plant for Telecom Sector Based on Embedded System

Modern Telecom Sector is eventually facing exceptionally tough challenges because of continuous and unexpected increase in power density requirement for the communicating machinery and equipment. To fulfil the power requirements for the equipment, a significant architecture and an optimal technique must be introduced. In this paper, a microcontroller-based optimization use of power-density has been carried out. Meeting above requirements, various equipment and electronic devices are employed. We have designed a microcontroller-based system via PROTEUS Virtual System Modeling to acquire efficient and effective results. The main focus of our work is to supply the power to Telecom equipment in meantime. The power is feeding on batteries and DG (Diesel Generator) set, depending on the condition of the power requirements. The changeover operations are performed by different relays, which are dully programmed via a microcontroller in Keil software. The power capacity of Telecom ((Telecommunication) equipment is ranged from 39-48 Volts DC. The rectification process is done by switch mode rectifiers instead of linear rectifiers. Because the switch-mode rectifier technology has brought fabulous improvements in power density as compared to linear rectifiers. This is done via simulation of the smart switch in PROTEUS software. The outcomes of the proposed system are costeffective in terms of fuel consumption of DG.

Development of a Prime Mover Emulator Using a Permanent-Magnet Synchronous Motor Drive

This paper presents the development of a surface-mounted permanent-magnet synchronous motor (SPMSM) drive for constructing the prime mover emulators. It draws power from the mains via a single-phase boost type switch mode rectifier (SMR) with good line drawn power quality and well-regulated dc-link voltage. The SPMSM drive control scheme can be arranged to drive the tested generator in a conventional speed control mode or a specific wind turbine torque–speed control mode. For performing the prime mover loading test, an interior permanent-magnet synchronous generator (IPMSG) followed by a three-phase Vienna SMR is established. It receives the mechanical driven power from the prime mover and establishes a 400 V dc-link for a dc microgrid. Various wind turbine torque–speed characteristic curves under different wind speeds can be faithfully emulated by the developed prime mover. And the maximum power point tracking function for the IPMSG followed by Vienna SMR is achieved using the perturb and observation method. The established whole prime mover emulator driven IPMSG system is evaluated experimentally under autonomous and microgrid interconnected operation.

Switch‐mode rectifier fed switched‐reluctance motor drive with dynamic commutation shifting using DC‐link current

Adequate commutation instant setting and tuning in accordance with varied operating conditions are required for achieving good winding current and developed torque responses for a switched-reluctance motor (SRM) drive. This study presents a dynamic commutation shift controller (DCSC) based on DC-link current ripple minimisation for SRM drives. A single-phase bridgeless switch-mode rectifier (SMR) fed SRM drive is established for making the performance evaluation. The robust control schemes of the SMR and SRM drive are properly designed to yield satisfactory dynamic and static operation characteristics. The boosted and well-regulated DC-link voltage is established from the mains to enhance the SRM drive performance under high speeds. In addition, good line drawn power quality with high efficiency is obtained simultaneously by the bridgeless SMR front-end. In the developed DCSC, the observed DC-link ripple current is processed and used to determine the commutation shift angle automatically. Some measured results are provided to demonstrate the performance of the established SMR-fed SRM drive under the commutation using the proposed DCSC.

The Best Conference You Never Attended [White Hot

The IEEE International Communications Energy Conference (INTELEC). INTELEC has a long history that predates PELS. INTELEC was the brainchild of several Bell Labs engineers who realized the need for such a conference. The first INTELEC was held in 1978 under the auspices of the IEEE Communications Society. INTELEC continued as an annual conference at host cities all over the world. In 1991, INTELEC was transferred to PELS. T he issues a nd themes of INTELEC have evolved over the years. In the 1970s, the papers were often about the newfangled switch mode rectifiers. In the 1980s, the papers were often about the evolving distributed power architectures used in telecom equipment. In the 1990s, a key topic was powering the network as the transmission medium evolved from twisted-pair copper wires to coaxial cable and optical fiber. In the 2000s, much of the discussion focused on powering the far-flung equipment of cellular telephone networks. In today's network, with all traffic, whether voice, video, or data, being digital, the differences between data center, telephone switching office, mobile base station, and telephone central office are blurring and dissolving. The power needs of such a network are rapidly evolving. How we manage and design the power systems and converters for these new networks is the key focus of INTELEC today.

Regenerative Skyhook Control for an Electromechanical Suspension System Using a Switch-Mode Rectifier

This paper proposes a mechatronic suspension system with capabilities of energy regeneration and semi-active control [i.e., skyhook (SK)], incorporated into the mechanism. The system overcomes the trade-off between energy consumption and ride handling/comfort in a semi-active/active suspension system. Central to the concept is the development of a switched-mode rectifier (SMR) capable of providing either a positive or negative damping ratio by controlling the electric current to alternate between regenerative and motoring modes. Using the implemented circuit, a regenerative SK control strategy is utilized to provide a continuous variable damping force that significantly improves the vibration isolation. Simulation results are presented to demonstrate power flow in both regenerating and motoring modes by utilizing a current controller. Furthermore, experimental results are presented highlighting performance of the regenerative suspension prototype in terms of power regeneration, sprung mass absolute acceleration, and relative displacement. In addition, both theoretical and experimental power conversion efficiencies in various segments of the mechatronic suspension are analyzed and reported.

A Bidirectional Boost Converter With Application to a Regenerative Suspension System

This paper proposes an algorithm to control the suspension dynamics with an energy regeneration capability and high conversion efficiency. Central to the concept is the development of a switched-mode rectifier (SMR) that is capable of providing either an equivalent positive or negative damping and alternating between regenerative and motoring modes. Simulation results are presented to demonstrate power flow in regeneration and motoring modes and verify the equivalent damping characteristic and vibration energy harvesting. The studies are conducted on a small-scale proof-of-concept electromagnetic suspension system excited by emulated International Standard Organization (ISO) 8608 road profiles. An autonomous start/stop algorithm is proposed such that autonomously turns on or off the converter. This mechanism mitigates quiescent power consumption of auxiliary integrated circuits (ICs) such as gate drivers and current transducers, therefore increasing the conversion efficiency of the power electronics throughout an ISO standardized variable-speed driving cycle. The autonomous start/stop algorithm is implemented experimentally to demonstrate its feasibility under typical standardized driving cycles.

Sensorless fuzzy‐logic‐based maximum power point tracking control for a small‐scale wind power generation systems with a switched‐mode rectifier

This study proposes a sensorless maximum power point tracking (MPPT) control using an improved variable-speed small-scale wind power generation system (WPGS) with a permanent magnet synchronous generator. The passive elements of a small-scale WPGS that use a conventional boost converter suffer from disadvantages that result in power losses, increased costs, and increased system size. Therefore, to eliminate the passive elements, the proposed system performs MPPT control to vary the duty ratio of a switched-mode rectifier. To evaluate the MPPT algorithms, a comparison was made between a fuzzy-logic-based perturb-and-observe (P&O) control with variable step size and a conventional P&O control with fixed-step size. A wind turbine model is investigated using a squirrel-cage induction motor, and the variable torque is controlled by varying the generator speed. The presented system and algorithm are verified by the simulations and experiments.

Position sensorless surface‐mounted permanent‐magnet synchronous generator and its application to power DC microgrid

This study presents a position sensorless surface-mounted permanent-magnet synchronous generator (SPMSG) and its application in powering DC microgrid. The derated characteristics of a PMSG with different AC–DC converters under brushless DC generator (BDCG) mode and the conventional switch-mode rectifier (SMR) mode are first comparatively assessed. Then a PMSG followed by three-phase three-switch Vienna SMR is established. Good operation performance is achieved via the proposed robust current and voltage control schemes. Second, a position sensorless control scheme based on observed extended back electromotive force (EMF) for the SPMSG followed by Vienna SMR is developed. The generation characteristics are enhanced by the developed starting and back-EMF angle tuning schemes. Third, a single-phase three-wire load inverter with the proposed novel robust waveform tracking control scheme is developed to yield good AC 220 V/110 V output voltage waveforms under unknown and non-linear loads. Some experimental results are provided to demonstrate the operation performances of the established SPMSG system in conventional generator with fixed output voltage and wind generator. More specifically, the BDCG mode and the SMR mode for operating a PMSG are experimentally evaluated.