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Özet

This study presents an Artificial Neural Network (ANN)-based adaptive switching frequency control strategy for series Direct current (DC) motor drives used in battery-powered mining locomotives, aiming to extend the lifetime of critical power-electronic components such as Insulated Gate Bipolar Transistors (IGBTs) and DC bus capacitors. In embedded systems for electric traction, two dominant degradation factors, motor current ripple and IGBT temperature fluctuation, significantly shorten component lifetimes. Conventional fixed switching frequencies impose a trade off: higher frequencies reduce current ripple but increase IGBT losses and temperature, while lower frequencies yield the opposite effect. Consequently, an adaptive variable switching frequency control algorithm is proposed to perform real-time decision making by predicting the optimal switching frequency that minimizes both motor current ripple and IGBT thermal fluctuations. The proposed algorithm was trained with a dataset acquired from current sensors, NTC temperature sensors, and a potentiometer defining the target current (PWM duty). Performance comparisons with a fixed frequency demonstrate that the ANN-driven approach maintains an average current ripple of less than 5% (average) and 10% (maximum), while the lifetime of the IGBT and capacitors improves. A fairness index was defined to quantify the relative lifetime improvement of the IGBT and capacitor, revealing that the proposed variable frequency switching model enhances the overall system performance by up to 13 times compared to fixed-frequency operation. These results confirm that the integration of embedded machine learning and adaptive control algorithms can substantially enhance the durability and efficiency of power-electronic systems in real-time industrial applications.

Özet

This paper presents the design and implementation of a high-efficiency, full silicon carbide (SiC)-based center-tapped phase-shifted full-bridge (PSFB) converter for NiCd battery charging applications in railway systems. The converter utilizes SiC MOSFET modules on the primary side and SiC diodes on the secondary side, resulting in significant efficiency improvements due to the superior switching characteristics and high-temperature tolerance inherent in SiC devices. A nanocrystalline-cored center-tapped transformer is optimized to minimize voltage stress on the rectifier diodes. Additionally, the use of a nanocrystalline core provides high saturation flux density, low core loss, and excellent permeability, particularly at high frequencies, which significantly enhances system efficiency. The converter also compensates for temperature fluctuations during operation, enabling a wide and adjustable output voltage range according to the temperature differences. A prototype of the 10-kW, 50-kHz PSFB converter, operating with an input voltage range of 700–750 V and output voltage of 77–138 V, was developed and tested both through simulations and experimentally. The converter achieved a maximum efficiency of 97% and demonstrated a high power density of 2.23 kW/L, thereby validating the effectiveness of the proposed design for railway battery charging applications.

Özet

This paper presents a novel approach to enhancing the performance and efficiency of phase-shifted full bridge converters through the integration of nanocrystalline cored integrated magnetics. The proposed design leverages the unique properties of nanocrystalline materials to achieve superior magnetic characteristics, such as high permeability, low core losses, and improved saturation flux density. By integrating nanocrystalline core integrated magnetics (NCIM) into the converter's significant advancements in power density and efficiency are achieved. The utilization of NCIM enables the reduction of core size while maintaining high energy storage capabilities, resulting in compact and lightweight converter designs. Additionally, the enhanced magnetic properties of NCIM facilitate soft-switching operation, leading to reduced switching losses and electromagnetic interference. Through detailed simulation and experimental validation, the effectiveness of the proposed nanocrystalline cored integrated magnetics design in optimizing the performance of phase-shifted full bridge converters is demonstrated. Overall, this research offers valuable insights into the application of nanocrystalline materials in power electronics, paving the way for the development of more efficient and compact converter systems for various industrial and renewable energy applications.

Özet

In this paper, first, a practical test methodology is proposed to apply the double-pulse test (DPT) and continuous operation test (COT) at the same test circuit/setup for the defined two tests, respectively. Secondly, this test setup and its practical implementation in the laboratory are described in detail for a 1.6 MW electrical multiple unit (EMU) traction converter. Next, the experimental results obtained for the traction converter power modules are given. Finally, the test results are evaluated according to the standard. In this work, it is demonstrated that the EMU traction converter power module's voltage overshoot, di/dt values, stray inductance, dynamic current sharing values and switching losses are obtained via DPTs while its IGBT module power loss, energy efficiency and static current sharing values are obtained via COTs. Also, the cooling plate's thermal performance is observed. These DPT and COT results show, acceptable power loss values and IGBT and diode junction temperatures with significant margins, reasonable current deviation among paralleled IGBT modules and reliable IGBT module switching characteristics. Also, the proposed methodology is suitable for performing investigation tests on power converters in general and substantially contributes to the power converter design such as gate driver optimization, DC-busbar design, and cooling plate design.

Özet

In critical applications of electrical machines, ensuring validity and safety is paramount to prevent system failures with potentially hazardous consequences. The integration of machine learning (ML) technologies plays a crucial role in monitoring system performance and averting failures. Among various motor types, permanent magnet synchronous motors (PMSMs) are widely favored for their versatile speed range, enhanced power density, and ease of control, finding applications in both industrial settings and electric vehicles. This study focuses on the detection and classification of the percentage of broken magnets in PMSMs using a pre-trained AlexNet convolutional neural network (CNN) model. The dataset was generated by combining finite element methods (FEMs) and short-time Fourier transform (STFT) applied to stator phase currents, which exhibited significant variations due to diverse broken magnet structures. Leveraging transfer learning, the pre-trained AlexNet model underwent adjustments, including the elimination and rearrangement of the final three layers and the introduction of new layers tailored for electrical machine applications. The resulting pre-trained CNN model achieved a remarkable performance, boasting a 99.94% training accuracy and 0.0004% training loss in the simulation dataset, utilizing a PMSM with 4% magnet damage for experimental validation. The model’s effectiveness was further affirmed by an impressive 99.95% area under the receiver operating characteristic (ROC) curve in the experimental dataset. These results underscore the efficacy and robustness of the proposed pre-trained CNN method in detecting and classifying the percentage of broken magnets, even with a limited dataset.

Özet

The effectiveness of MPPT algorithms deteriorates by having more Maximum Power Points (MPPs) on the characteristics of the PV array. The number of MPPs can increase with the different connection types of PV panels and the pattern of partial shading, and it also changes the P–V (Power–Voltage) characteristics of the panel. Therefore, it is important to consider different combinations of algorithms, connection types and partial shading patterns for an effective PV plant design. This study assesses the performance of a PV power plant including a 5 × 5 PV array by considering eight different connection types, six partial shading conditions (PSCs), and three well-known MPPT algorithms, all together, on the TMS320F28335 DSP platform. The obtained results and analyses show that the TCT (Total Cross Tied) connection type has higher performance than the other connection types under all PSCs with an average of 25.98% Mismatched Loss (ML), 54.3% Fill Factor (FF) and 13.45% efficiency (η). As for the shading patterns, the Diagonal (DG) pattern has less effect on the system’s ML and FF values, and the Long Wide (LW) pattern is less effective in reducing system η. Regarding the algorithms, it has been proven that the performance of a PV system using the simplest form of the basic algorithms can reach the performance of the system using complex algorithms when the connection type is well-adjusted according to the shading patterns. Overall, the given analyses and results prove the significance of taking into account the combination of different MPPT algorithms, types of panel connections, and partial shading patterns to enhance PV system power efficiency and reduce the complexity of PV power plant installations.

Özet

Power electronic systems are rapidly evolving; thus, effective prototyping methods are required to test control algorithms and assess system performance prior to hardware implementation. This research suggests a Model-In-The-Loop (MIL), Software-In-The-Loop (SIL), and Processor-In-The-Loop (PIL) methodologies-based complete prototyping strategy for flyback converters using the TI F28069M Launchpad kit. These techniques can be combined to evaluate control strategies accurately and quickly, speeding up design cycles and enhancing system reliability. The proposed prototyping platform is presented in this work, along with a thorough explanation of each prototyping stage and its associated advantages. The effectiveness of the suggested approach for 50W rated power flyback converter in terms of quick algorithm development, system simulation, real-time control implementation and controller design accuracy is analyzed and shown by experimental results. The results show that the performance of the designed controller for the flyback converter is almost the same as in MIL and SIL implementation in terms of the overshoot and settling time in the reference voltage tracking. On the other hand, in the PIL implementation, the overshoot performance of the controller deviates by 1.18% more than in SIL and MIL implementation. These also confirm that the flyback control system's performance is reliable and effective during all phases of development.

Özet

In order to increase the efficiency of electric locomotives, DC bus capacitors in inverters/converters and motor life, as well as to reduce the risk of failure, a method using variable switching frequency is proposed to keep torque fluctuation of the motor and the losses on the high current carrying IGBT of the motor control units on set value. In the proposed method, the switching frequency is determined adaptively depending on the duty and line current. Furthermore, it has been observed that the current fluctuation of the motor is kept below a specified threshold and the IGBT switching losses are reduced.

Özet

The traction system is one of the critical subsystems consisting of different components to ensure the movement of rail vehicles. The energy taken from the catenary is controlled by the traction converter and transferred to the traction motors. There exists a single-phase active PWM rectifier and three-phase inverter units in the traction converter architecture. By the nature of the rectifier's design, it creates a voltage component at their output at a frequency of 2 times the AC voltage at the input. If a hardware filter is not placed due to the additional cooling need, volume and hardware design limitations at the rectifier output, fluctuation is observed in the output voltage. The fluctuation in the DC voltage directly affects the drive system and causes a torque oscillation in the traction motor. In traction systems, the switching frequencies of the semiconductors are low in order to reduce the thermal losses and high voltage. That means semiconductors have low control bandwidth, so the effect of fluctuating DC voltage on torque ripple cannot be suppressed by conventional methods. In converters that comply with this definition, the fluctuating DC voltage reflects on the motor currents so that it causes a fluctuation in motor torque at the level of 2 times the catenary voltage frequency, which is 100 Hz in the present study. Reducing the torque fluctuation is critical for the requirement that the motor torques of the railway vehicle specified in IEC 60349-2, which is one of the railway driving standards, must be within a certain tolerance. This paper aims to take counteraction by continuously measuring the angle and frequency of the 100 Hz fluctuation. The proposed method on which the converter's action against the fluctuation of motor torque is that the voltage applied to the motor is manipulated according to the phase and amplitude of the alternating DC voltage.

Özet

Estimation error in SMO control is inevitable, and it is generated because of its sign function. In this work, a sliding mode observer is employed, and the error in this method is reduced by applying varying notch filters in the system. A sign function is employed to determine the hyperplane. By multiplying the sign function of estimated value minus real value, the sliding surface is defined. If the sliding surface converges to zero, the error between the estimated and real value approaches to zero. The sign function, which is the main part of SMO, creates oscillations in the system and causes chattering in IPMSM. In order to overcome this obstacle, filtering the oscillated frequency is proposed. The range of the frequency that is being eliminated from the output of SMO should be narrow so that a notch filter is suggested to attenuate the oscillation frequency. In this case, in which the parameters of IPMSM have already been defined, the oscillated frequency for reference speed of 0.1 pu is obtained from the FFT analysis of the signal, which is 27.34 Hz. After simulating the proposed method in MATLAB®/Simulink® and filtering the aforementioned frequency from the estimated speed, a significant reduction in the first harmonic oscillation of the signal is achieved, and according to its FFT frequency response, its amplitude is decreased from 0.14 to 0.05 when the motor is rotating at 0.1 pu. In conclusion, this method has reduced chattering in the system and attenuated the frequency, which leads to estimation error mitigation, and increases the robustness and accuracy of the position sensing of IPMSM.

Özet

Offline stator resistance estimation for a sliding mode observer-based PMSM speed control algorithm has been experimentally verified using MATLAB®/Simulink® and Simscape Electrical. The experimental kit includes a low-cost evaluation and development board LAUNCHXL-F28069M with a C2000 real-time microcontroller. DRV8301 has been chosen as an inverter board due to the compatibility of the nominal current and voltage ranges of the 52.5-watt PMSM. Thanks to the code generation future of the Embedded Coder® toolbox, experimental results show that the estimated resistance is more accurate compared with the stator resistance value measured by an expensive RLC meter.

Özet

Silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs) have many advantages compared to silicon (Si) MOSFETs: low drain-source resistance, high thermal conductivity, low leakage current, and high switching frequency. As a result, Si MOSFETs are replaced with SiC MOSFETs in many industrial applications. However, there are still not as many SiC modules to customize for each application. To meet the high-power requirement for custom applications, paralleling discrete SiC MOSFETs is an essential solution. However, it comes with many technical challenges; inequality in current sharing, different switching losses, different transient characteristics, and so forth. In this paper, the detailed MATLAB®/Simulink® Simpscape model of the SiC MOSFET from the datasheet and the simulation of the half-bridge circuit are investigated. Furthermore, this paper proposes the implementation of the four-paralleled SiC MOSFET half-bridge circuit with an improved symmetric gate driver layout. Moreover, a unique laminated busbar connected directly to the printed circuit board (PCB) is proposed to increase current and thermal capacity and decrease parasitic effects. Finally, the experimental and simulation results are presented using a 650 V SiC MOSFET (CREE) double-pulse test (DPT) circuit. The voltage overshoot problems and applied solutions are also presented.

Özet

Maximum Power Point Tracking (MPPT) systems enable photovoltaic (PV) panels to work at their Maximum PowerPoint (MPP). To do this, several algorithms have been developed, including conventional, intelligent, and meta-heuristic. Once a partial shading condition (PSC) occurs, more than one peak emerges in the power-voltage curve of photovoltaic arrays. Under PSCs, conventional algorithms get stuck at the local maximum point and fail to reach the global maximum point. Being an alternative method, Particle Swarm Optimization (PSO) algorithm has been frequently employed for MPPT systems under PSCs. This algorithm has some parameters that affect its performance to reach the global MPP of the PV panel. Therefore, with well-tuned parameters, the effectiveness of the PSO will increase for the different PSCs. In this study, the effects of the cognitive learning and social learning parameters of the PSO algorithm are investigated under different PSCs. To achieve this, an MPPT system, including a boost-type DC-DC converter, is created in MATLAB®/Simulink®. Simulation studies show that the PSO algorithm fails to track global MPP with constant cognitive and social learning parameters under changing partial shading conditions. Furthermore, the results show that these two parameters affect the time to reach the MPP of the PSO algorithm.

Özet

Maximum Power Point Tracking (MPPT) systems enable photovoltaic (PV) panels to work at their Maximum Power Point (MPP), which can significantly increase PV system efficiency. To do this, several algorithms have been developed, including conventional, intelligent, and meta-heuristic. Once a partial shading condition (PSC) occurs, more than one peak emerges in the power-voltage curve of photovoltaic arrays. Under this condition, conventional algorithms get stuck at the local maximum point and fail to reach the global maximum point. Being an alternative method, a metaheuristic algorithm Particle Swarm Optimization (PSO) has been frequently employed for MPPT systems under partial shading conditions. This algorithm has some parameters that affect its performance to reach the global MPP of the PV panel. Therefore, with well-tuned parameters, the effectiveness of the PSO will increase for the different partial shading conditions. In this study, the effects of cognitive learning and social learning parameters of the PSO algorithm are investigated under different partial shading conditions. An MPPT system consisting of 3 series PV panels, a boost-type DC-DC converter, and the PSO algorithms is created in MATLAB®/Simulink®. Simulation studies show that the PSO algorithm fails to track global MPP with constant cognitive and social learning parameters under changing partial shading conditions. Furthermore, the results show that these two parameters affect the time to reach the MPP of the PSO algorithm.

Özet

With the increase in prosperity level and industrialization, energy need continues to overgrow in many countries. In particular, individual energy prosumers (someone that both produces and consumes energy) head toward smart home energy management systems (SHEMS) that include renewable energy sources in their homes. By integrating PV solar panels into houses, there is a need to optimize home energy production/consumption scenarios by consumer behavior. In this study, an intelligent residential energy management architecture and algorithm to manage residential energy production/consumption are proposed. The algorithm controls the energy flow in the home according to real-time potential solar power estimation, demanded energy estimation, electricity consumption price, and battery state-of-charge (SoC). The fuzzy logic algorithm has been developed to determine the estimated comfort and cost-effectiveness ratios in the near future. The simulated annealing algorithm, a meta-heuristic algorithm, is performed to obtain the best operating point decision of the battery using the comfort and cost-effectiveness ratios. Energy flow direction and battery SoC are optimized using simulated annealing based on the comfort and cost-effectiveness ratio (comparison of alternatives with respect to multiple criteria of different levels of importance for energy usage). The focus is to generate maximum profit from energy sales for monthly profit to be achieved. Prototyped hardware and software are implemented and tested in real-time. The test results show that the 20% reduces energy consumption, and a monthly gain of $89.2 is obtained from energy sales using the proposed method. Therefore, the test results reveal the effectiveness of the proposed architecture and algorithm.

Özet

An on-line compensation for the dead time strategy without the knowledge of the current direction is proposed for PMSM drive based on a current observer. The modifications of the motor reference voltages are achieved by an uncomplicated current observer working in conjunction with the feedforward dead time voltage estimator. Therefore, the distortions on phase currents and torque due to dead time are greatly reduced. The proposed method does not require look-up table and coordinate transformations. It also does not need phase current polarity information or calculation of dead time period. Since the proposed scheme requires no extra hardware and time consuming signal processing algorithms, it is appropriate to use in real-time implementation of AC drives. The proposed scheme has been validated in simulation and implemented using TMS320F28335 DSP. Simulation and practical results validate the effectiveness and the feasibility of the proposed scheme.

Özet

This paper proposes a new application of the performance improvement of grid voltage for the double-fed induction generator, the brushless double-fed induction generator and the brushless double-fed reluctance generator. In order to enhance the performance of the wind energy system, three local electrical storage systems are associated with a Li-Ion battery, a supercapacitor and a hybrid rechargeable electrical energy storage. These storage systems can compensate for the variation of the power demand. Also, the fluctuation in the generated electrical energy is occurred due to different wind speed in the wind energy system. The originality of this study inclines in the new application by using the hybrid rechargeable electrical energy storage in the back-to-back converter of wind energy conversion system. The proposed controls are the active-reactive control for rotor side converter, the direct power control for grid side converter to operate the double-fed generators. The performance of the three local electrical storage system shows that the proposed hybrid local storage system has better energy management, higher efficiency and lower total harmonic distortion of the grid voltage.

Özet

A Single-Ended Primary-Inductor Converter (SEPIC) converter with an Inductor-Capacitor (LC) regenerative snubber is proposed to reduce Electromagnetic Interference (EMI) for Electric Vehicle (EV) applications. The switching energy is transferred through a capacitor to an inductor which is coupled to SEPIC inductors. This technique reduces the number of components and also returns some of switching energy to SEPIC converter. The mathematical analysis and optimization of LC snubber with respect to number of turns is also presented. Spice simulations and experimental results are provided to verify its performance. The proposed LC regenerative snubber reduces the peak voltage by 16 V on the switching transistor during the switching transient. It is also indicated that 8 dB reduction is achieved in the EMI measurements at ringing frequency and 10 dB reduction at high frequency band.

Özet

A modular multilevel converter (MMC) is an advanced voltage source converter applicable to a wide range of medium and high-voltage applications. It has competitive advantages such as quality output performance, high modularity, simple scalability, and low voltage and current rating demand for the power switches. Remarkable studies have been carried out regarding its topology, control, and operation. The main purpose of this review is to present the current state of the art of the MMC technology and to offer a better understanding of its operation and control for stationary applications. In this study, the MMC configuration is presented regarding its conventional and advanced submodule (SM) and overall topologies. The mathematical modeling, output voltage, and current control under different grid conditions, submodule balancing control, circulating current control, and modulation methods are discussed to provide the state of the MMC technology. The challenges linked to the MMC are associated with submodule balancing control, circulating current control, control complexity, and transient performance. Advanced nonlinear and predictable control strategies are expected to improve the MMC control and performance in comparison with conventional control methods. Finally, the power losses associated with the advanced wide bandgap (WBG) power devices (such as SiC, GaN) are explored by using different modulation schemes and switching frequencies. The results indicate that although the phase-shifted carrier-based pulse width modulation (PSC-PWM) has higher power losses, it outputs a better quality voltage with lower total harmonic distortion (THD) in comparison with phase-disposition pulse width modulation (PD-PWM) and sampled average modulation pulse width modulation (SAM-PWM). In addition, WBG switches such as silicon carbide (SiC) and gallium nitride (GaN) devices have lower power losses and higher efficiency, especially at high switching frequency in the MMC applications.

Özet

A PMSM drive with an incremental encoder or using sensorless control requires alignment to a predetermined rotor position (initial position) or initial rotor position detection at start-up. It is desired to lock the rotor to a known state (usually zero angle) at start-up if the initial rotor position detection is not available or difficult to obtain. In this work, a simple and proper zero angle initial rotor position alignment of four-switch three-phase (FSTP) inverter-based PMSM drive is proposed. Low-frequency voltage signal is applied to the d-axis voltage reference of the open-loop FSTPI based PMSM drive scheme without requiring complex trigonometric calculations, PI current regulators and current sensing. Therefore, fluctuated capacitor voltages at the DC-link are obtained allowing current flown through phase a locking the rotor with zero angle, properly. The proposed method has been implemented using a low-cost FSTP voltage source inverter (VSI) for PMSM drive with a floating-point TMS320F28335 DSP. The effectiveness and the feasibility of the proposed zero angle initial rotor position alignment method for PMSM driven by FSTP inverter have been demonstrated through experimental results.

Özet

An analytical model of excitation system of brushless wound-rotor synchronous starter generator for aircraft applications is developed and presented in this study. During engine start-up process, the starter generator operates as a motor to start the aircraft turbine and to assist it up to the self sustaining speed. On the basis of rotation speed of the starter generator in the engine start-up process, there are three excitation modes for the exciter and two transient modes for the field current of the main generator (MG). In this study, for each excitation mode, the relationship between the excitation current (field current of the exciter) and the field current of MG is investigated by taking into account the influence of power electronic parts. This study also proposes a control method for the generator field current in all excitation modes which can detect optimum operating points for transition between excitation modes. Furthermore, a seamless transient control strategy is proposed for the transient modes of the generator field current. Simulation and experimental results are provided to demonstrate the feasibility of the proposed solution.

Özet

Electric powertrains are subject to vibrations due to weak damping and fast torque response of electric motor. In this study, a PD controller is developed to damp the vibrations. By using PD controller, two solution methods are developed. First solution is to use the wheel speed sensors available in all four wheels. Second solution is to use a reduced order observer to estimate the wheel speed. Differentiation of motor speed and wheel speed is input to the PD controller. Output of the PD controller is the torque damping feedback to the torque reference. Simulation model is developed including a flux vector controlled permanent magnet synchronous motor, powertrain model and vibration controller. The results demonstrate the validity and effectiveness of the proposed scheme.

Özet

A 240 Watt output power SEPIC converter with an output voltage of 24 V is proposed to be used in automotive and railway LED applications. The input voltage of the converter varies between 16 V and 36 V. The stability of the converter is guaranteed by moving one of the dominant pole to lower frequency and canceling the other pole with a zero. The phase margin is higher than 56° across all input voltage values. The transients of the switch is damped using a passive snubber circuit. Electromagnetic analyses are performed using Ansys SiWave™ to determine voltage drop, current distribution, near and far field and resonance behavior of SEPIC converter. Measurement results indicate that the SEPIC converter is stable under various operating conditions.

Özet

The main aim of this paper is to provide electric power generation using a renewable and portable method in rural and geographically problematic areas where energy transmission is not possible. Electric power generation from wind with low-cost, efficient and portable small-scale wind turbine during natural disasters (earthquake, fire, flood, etc.) leading to catastrophic consequences (long electrical black-outs) and for individual low power applications is targeted. The control of gearless Permanent Magnet Synchronous Generator (PMSG) along with load side inverter control in this project are performed using a full-rating, bi-directional, two-level, back-to-back voltage source rectifier/inverter with total of 8 switches for the variable speed wind turbine. Therefore, one of the major advantages and novelty of using MRAS rotor flux linkage and stator resistance estimator in this system is to correct changes in the flux and stator resistance values in the control system. Due to its simplicity and effectiveness, the load side control is achieved by using four switch grid side inverter. To observe the total system performance, a three-phase passive load is used at the inverter output. The low-pass LCL filter is designed and used in the load side to reduce current and voltage harmonics and increase stability and efficiency of the power network. The results of the overall system are validated with the real-time DSP system. It is proved with this paper that the inclusion of a simple, effective and economical position sensorless control in the generator side show that renewable wind energy system can be a viable distributed green energy solution for rural areas.

Özet

A low-cost position sensorless speed control method for permanent magnet synchronous motors (PMSMs) is proposed using a space vector PWM based four-switch three-phase (FSTP) inverter. The stator feedforward dq -axes voltages are obtained for the position sensorless PMSM drive. The q-axis current controller output with a first order low-pass filter formulates the rotor speed estimation algorithm in a closed-loop fashion similar to PLL (Phase Lock Loop) and the output of the d-axis current controller acts as the derivative representation in the stator feedforward voltage equation. The proposed method is quite insensitive to multiple simultaneous parameter variations such as rotor flux linkage and stator resistance due to the dynamic effects of the PI current regulator outputs that are used in the stator feedforward voltages with a proper value of K gain in the q-axis stator voltage equation. The feasibility and effectiveness of the proposed position sensorless speed control scheme for the PMSM drive using an FSTP inverter are verified by simulation and experimental studies.

Özet

In order to reduce the adverse effect of parameter variation in position sensorless speed control of permanent magnet synchronous motor (PMSM) based on stator feedforward voltage estimation (FFVE), multiparameter estimation using a model reference adaptive system is proposed. Since the FFVE scheme relies on motor parameters, the stator resistance and rotor flux linkage are estimated and continuously updated in the FFVE model in a closed-loop fashion, and the sensitivity to multiparameter changes at low speed is eliminated. To improve the dynamics and stability of the overall system and eliminate transient oscillations in speed estimation, a phase-locked loop like speed estimation method is proposed, which is obtained by passing the q-axis proportional integrator (PI) current regulator output through a first-order filter in the FFVE scheme. The proposed control method is similar to V/f control as in induction motors; therefore, starting from zero speed is possible. The experimental tests are implemented with 1-kW PMSM drive controlled by a TMS320F28335 DSP. The proposed sensorless scheme is also compared with the classical sliding mode observer (SMO). Experimental results show that the proposed sensorless scheme exhibits greater stability at lower speed than the classical SMO under parameter detuning. Experimental results and stability analysis demonstrate the feasibility and effectiveness of the proposed sensorless scheme for PMSM under various load and speed conditions.

Özet

An FPGA based Bluetooth controlled robot with encoder fault tolerant algorithm is presented. The smart phone is used to obtain user intentions, such as turning, speeding or braking and this data is sent to a robot using Bluetooth. The motor control algorithms and robot communication interfaces are implemented on FPGA for parallel processing. The robot is capable of changing its position with the help of two independent PI closed loop speed controlled DC motors. The motor speed is determined by the accelerometer of the sensor data of a smart phone. The FPGA receives speed information and generates appropriate PWM signals. Motor rpm is calculated via rotary encoder. In case of an encoder failure, an on-board gyroscope helps maintaining normal operation. An Android based smart phone application has been developed. MATLAB is used for simulating an encoder failure and observation of results. The motor control algorithm has been implemented using Verilog and tested on the field.

Özet

A simple and efficient position sensorless control method based on feedforward voltage estimation for PMSG improved with multi-parameter estimation using MRAS is proposed in this paper. The dynamically enhanced stator feedforward dq‒axes voltages that are derived from steady-state PMSG model are modified for the sensorless drive. In direct-drive wind turbine systems, because of low back-EMF amplitude in the generator output at very low speed operation, the rotor flux linkage cannot be predicted correctly. Vector control is often used in PMSG control, because it has a simple structure and is suitable for various industrial systems. In the power equation, maximum power is obtained as a function of torque and speed. In the proposed method, a variable-speed wind turbine system with back to back converter structure is connected to common DC-link. In this paper, the proposed sensorless control scheme has been implemented with 1 kW PMSG drive controlled by a TMS320F28335 DSP for low speed at 0.1 p.u. (300 rpm) is achieved under multi-parameter variations.

Özet

This paper investigates an ordinary least squares based indirect field oriented control (IFOC) of induction motor at very low speed range (1-5 rpm) using a low-count encoder. At very low speeds the speed estimation provided by common techniques for low-count encoder applications such as averaging the last two speed samples and/or considering the previous speed value until the next position update can generate erroneous speed results which can cause instability in the overall control system. By proposing ordinary least squares (OLS) method with low-resolution position sensor based speed estimation for IFOC of IM drives more realistic speed can be obtained by fitting the predefined sets of speed data in a linear or quadratic manner. Experimental tests prove that the proposed scheme which is constituted of OLS (linear) speed estimation algorithm increases stability and improves low and oscillating speed performance of IFOC of IM drive with low-count encoders down to four pulses per revolution.

Özet

Sector determination for a normalised space vector pulse width modulation (SVPWM) scheme is proposed for four-switch three-phase (FSTP) voltage source inverter (VSI) by using already available stationary reference frame stator voltages without requiring complex trigonometric calculations. The proposed method has been simulated by using MATLAB/Simulink and implemented using a VSI with a TMS320F28335 floating-point digital signal processing. Simulation and experimental results show the feasibility and effectiveness of the proposed SVPWM algorithm for FSTP inverter.

Özet

A simple and efficient fault detection and parameter monitoring algorithm for electro-hydraulic power steering (EHPS) system is proposed using model reference adaptive system (MRAS) without any additional sensor. In a faulty situation where the hydraulic system is disabled, assisted power is provided by an electric motor. Therefore, in low speed maneuvers, during sudden direction changes and parking, some parameters of an electric motor in EHPS are affected. These changes threaten the vehicle's driving reliability and performance of EHPS. In this study, an EHPS system with rotor flux estimation based adaptive driver torque control principle has been presented. The motor winding temperature is obtained for monitoring purpose with the help of MRAS stator resistance estimation. The proposed parameter estimation method for EHPS has been simulated by using AMESim and MATLAB/Simulink cosimulation model. Simulation results demonstrate the feasibility and effectiveness of the proposed method.

Özet

This paper deals with using an original and pure electronic method for low-frequency harmonic suppression with wide industrial realization and application, in place of the usually heavy inductive, low-frequency harmonic filters. One of the main applications was made for small land power supply units of onboard complexes in ground-based air navigation when preflight ground check-service is made. The transport management at thousands of small provincial airports in the former country is still unfortunate. The same situation is in Northern and central Central Asia, Northern Caucasian and Trans-Caucasian Mountains, oriented to small civil and agricultural services airports, etc. Everywhere the phase and line voltage amplitude unbalance can reach between 10-15% at the settlement’s power tiny transformer or generator and there are thousands and thousands of such local «airports» [1, 6].

Özet

In this study, modeling and simulation of a speed sensor driven field‑oriented control (FOC) of a permanent magnet synchronous motor (PMSM) drive is developed by using MATLAB Function blocks in MATLAB/Simulink. This method allows easier algorithm and software development stages for experimental studies compared to the classical block diagram approach. The superiority of the method over commonly used “Code Generation” tools is also emphasized. First, a MATLAB/Simulink model of the FOC of PMSM drive is developed using MATLAB programming in MATLAB Functions similar to C coding techniques. The results of the simulation are presented. Then, the MATLAB‑programming based codes developed in simulation are implemented in a TMS320F28335 floating‑point MCU using C programming language and experimental results are obtained. Finally, the results of simulation and experiments are compared.

Özet

In this study, modeling and simulation of a speed sensored field‑oriented control (FOC) of a PMSM drive is developed by using MATLAB Function blocks in MATLAB/Simulink, enabling easier algorithm development compared to classical block diagram approaches. Following simulation, the MATLAB‑Function based code was implemented on a TMS320F28335 floating‑point MCU and experimental results were obtained and compared.

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This paper discusses controlled exciting systems for special brushless synchronous motors under cycling load, designed to maintain cos φ ≈ 1 in harsh environments (±60 °C). A smart brushless synchronous machine (SBSM) was developed with diode‑bridge rectifier excitation and constant‑current self‑stabilizing effect, applied in industrial contexts such as deep‑well oil pumps.

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The paper investigates excitation systems for brushless synchronous machines operating under extensive variable load, maintaining cos φ ≈ 1 without controlled electronics. A modified motor construction avoids electronic control and uses diode excitation to stabilize power factor, offering benefits for oil‑field SBSM drives.

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This paper explains the autonomous vehicle development process at Okan University, detailing a three‑stage project implemented via LIDAR, electronic control of steering/throttle/brakes, and planned GPS/sensors integration. The first two stages were completed by March 2012.

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This paper investigates position‑sensorless direct torque and indirect flux control of a BLDC motor with non‑sinusoidal back‑EMF. It presents a dq‑frame based DTC scheme, utilizing look‑up tables of back‑EMF constants to achieve low‑frequency torque‑ripple‑free operation without PWM or PI controllers. Simulations and experiments verify the method's validity and application potential.

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This paper presents a direct torque control (DTC) technique for BLDC motors with non‑sinusoidal back‑EMF using a four‑switch inverter in constant torque region. It introduces two‑phase conduction mode, and a novel switching pattern via voltage‑vector look‑up tables, achieving faster torque response and reduced torque oscillations over traditional schemes.

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The integrity of electric motors in work and passenger vehicles can best be maintained by frequently monitoring their condition. This paper presents a signal‑processing‑based fault‑diagnosis scheme tested for rotor asymmetry detection at zero speed (startup or idle), overcoming challenges of noisy spectra and operational vibrations. Implemented using the inverter sensor and TMS320F2812 DSP, results show its reliability and practical no‑cost integration for HEV powertrains.

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A detailed signal‑processing based motor fault‑diagnosis technique is described for zero‑speed rotor asymmetry detection, effectively addressing noisy spectral issues under real-world vehicle vibration. The implementation on a TMS320F2812 DSP demonstrates robust, online fault‑signature monitoring for hybrid‑electric vehicle powertrains.

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Presents a sensorless DTC/IFC strategy for BLDC motors with non‑sinusoidal back‑EMF, demonstrating high performance through experimental validation and implementation without requiring position sensors.

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Proposes a PFC algorithm integrated with DTC in BLDC drives using two‑phase conduction mode and boost converter, significantly improving power factor from ~0.77 to ~0.9997 in experiments.

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Investigates a PWM modulation strategy aimed at reducing bearing currents in five‑phase AC machines, demonstrating effectiveness through experimental studies.

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Introduces a signal‑processing based on‑board fault‑diagnosis scheme for hybrid-electric vehicle induction motors, targeting rotor asymmetry at startup and idle. Problems with air‑gap noise and vibrations are addressed by zero‑speed testing. Implemented via inverter sensors and TMS320F2812 DSP with no additional cost; experiments confirm detection of fault harmonics at standstill.

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Presents a two‑phase conduction DTC method for BLDC motors with non‑sinusoidal back‑EMF in the constant torque region, eliminating PWM. The scheme uses a look‑up table for voltage vectors to produce quasi‑square currents, improving torque response and reducing algorithms needed. Simulations and experiments validate the concept.

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Investigates indirect field‑oriented control of induction motors at 1–5 rpm using low‑count encoders. A method converts high‑resolution encoder signals to low counts, identifies optimal encoder resolution, and resolves DSP computational issues. Verified on TMS320F28xx DSP‑based traction drives.

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Describes a low‑cost DTC scheme for PM synchronous motors using Hall‑effect sensors to replace expensive encoders/resolvers. Eliminates dc‑link sensing and handles initial position, resistance drift, and low‑speed issues. Validated in washing machine agitation application, outperforming conventional control.

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A method for directly measuring the internal resistance of batteries or supercapacitors using a multimeter and switch, enabling accurate resistance determination in power supplies with minimal instrumentation.

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Describes an open-loop to closed-loop sensorless control scheme transition for PMSM startup, aligning estimated rotor angle with commanded ramping angle to minimize startup spikes and oscillations.

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US patent covering smooth motor startup method: transitions from open-loop to sensorless closed-loop control by aligning rotor and ramp angles to avoid current spikes.

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Application for US patent on smooth PMSM startup, detailing technique to transition between control schemes by reducing rotor/ramp angle difference.

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