Precise Speed Control Research Articles

Closed Loop Control for a Brushless DC Motor to Run at the Exactly Entered Speed

The project is designed to control the speed of a BLDC motor using closed loop control technique. BLDC motor has various application used in industries like in drilling, lathes, spinning, elevators, electric bikes etc. The speed control of the DC motors is very essential. This proposed system provides a very precise and effective speed control system. The user can enter the desired speed and the motor will run at that exact speed. Based on the principle of PWM speed can be controlled. This is achieved by keeping BLDC motor on closed loop feedback by giving RPM reference to the microcontroller upon a shaft mounted IR reflection arrangement. The pulse width modulation would be automatically adjusted to maintain the DC power to the motor such that entered speed percentage matches the RPM. An LCD duly interfaced to the microcontroller to display the running speed. The desired speed in percentage of full speed is fed with the help of keypad. The controller delivers desired pulse width to automatically adjust the DC power to the motor for required speed. The above operation is carried out by using one thyristor for driving the BLDC motor with IR sensing for getting the speed reference to the microcontroller. The power supply consists of a step down transformer 230/12V, which step down the voltage to12V AC. This is converted to DC using a Bridge rectifier and it is then regulated to +5V using a voltage regulator. Which is required for the operation of the microcontroller and other components Further the project can be enhanced to a fully-fledged fuzzy logic control of a BLDC motor for industrial applications. It can also be developed for an intelligent cruise control used in modern auto mobiles these days..

Feasibility of Underwater Treadmill Training to Improve Mobility

Underwater treadmill training (UTT) has been shown to be successful in improving health related fitness in inactive populations with reduced mobility. Walking on a treadmill submerged in a self-contained tank of water allows for precise control of walking speed, water depth, and water temperature while unloading one’s body weight. PURPOSE The purpose of this study was to determine the feasibility and efficacy of an 8-week (3d[BULLET OPERATOR]wk-1) UTT program in a unilateral, transtibial amputee with limited ambulation potential. The hypothesis was that the participant’s post-UTT and three month scores relative to pre-UTT scores would improve in mobility (Amputee Mobility Predictor [AMP]), walking speed (10-M Walk Test), balance (single leg stance and Romberg test), and fall risk (Timed-Up-And-Go [TUG]). METHODS The patient was a 72 year-old male who underwent transtibial amputation for the development of an infection coupled with Charcot neuroarthropathy. He has used a prosthetic device two years. He walks with a cane in the community and uses a wheelchair while at home. Mobility is defined by the Medicare Functional Class K-Level system with stages ranging from K-0 to K-4 and is determined by the score of the AMP. Prior to UTT, a prosthetist administered the AMP and classified the patient as a K-2 with a total score of 32. The patient had a secondary prosthetic limb which was fitted by the prosthetist for use in the underwater treadmill. RESULTS After UTT, the patient was classified as a K-3 with a total score of 37. Time to complete the 10 M Test was 12.8 s before, 11.4 s after, and 11.1 s at 3-months. TUG test times pre, post, and 3 months post-UTT were 15.6 s, 13.5 s, and 13.3 s, respectively. The patient was unable to balance for 30 s with eyes closed before UTT and was able to complete this task after UTT and 3-months post-UTT. He was unable to perform a single leg balance test without assistance for 30 s on either limb at any time-point. Total underwater treadmill walking time increased from 26 min to 48 min and walking speed increased from 1.1 mph to 1.6 mph. CONCLUSION: Following UTT, the patient achieved a higher K-level. Patients classified as a K-3 or higher are eligible for health care coverage for higher level componentry for the prosthetic device. His walking speed improved and fall risk decreased following UTT with only minor improvements in balance.

Design and implementation of an advanced controller in plant distributed control system for improving control of non-linear belt weigh feeder

A Belt Weigh Feeder (BWF) is a flat belt conveyor designed for feeding bulk material into a chemical process in a controlled fashion for better process control. The dynamic weight of bulk material is measured with a belt weigh bridge and the belt speed is controlled to compensate for any variation in the weight so that the mass feed rate is maintained as per the set feed rate. The problem of belt speed control is challenging as the dynamic response of system is non-linear and there are frequent changes in belt load due to variation in bulk material characteristics. The control accuracy of belt weigh feeder is fully dependent on the controller’s performance in providing precise control of speed of motor/belt. Any delay in achieving the set feed rate or frequent deviation between set and actual feed rate affects the quality and efficiency of downstream process. Conventional PI controller is unable to provide optimum control due to system non-linearity. To overcome this problem, in this paper first the operating data of the BWF system is analysed and the nature and cause for the nonlinearity is investigated. The system is then modelled using the design parameters of plant belt weigh feeder, which is then simulated to have a better insight into its non-linear response. Subsequently, based on simulation results, a PI Fuzzy Logic (PI-FL) controller is designed to improve the control accuracy of the system. Further, to ensure the stability of the system, an adaptive controller is introduced in cascade to fine tune the gains of PI-FL controller as per the operating speed of the BWF. Finally, an advanced PI-FL with cascade adaptive controller is implemented in the plant DCS (microprocessor based process control system). The actual test results indicate reduction in the Integral of Absolute Error (IAE) of the system by about 34% using this controller.

Scheme based on buck‐converter with three‐phase H‐bridge combinations for high‐speed BLDC motors in aerospace applications

High reliability and safety are critical in aerospace applications. This study introduces a novel high-reliable inverter scheme based on buck-converter with three-phase H-bridge combinations and a high-accurate commutation instant shift correction method for high-speed brushless direct current (BLDC) motors. First, the traditional three-phase inverter and buck-converter-based BLDC motor drive system are analysed. Second, the zero-crossing points of back-electromotive force detection circuit are designed and the position detection error is analysed. Third, a speed measurement with enhanced detection frequency and accuracy is proposed. Then, a fast two-stage commutation instant shift compensation method is designed based on the unique speed measurement method. High-reliable and accurate commutations are achieved especially in the high-speed steady state, which improves the speed control precision and decreases the motor driving loss. Finally, the control system design process is proposed and a fault-tolerant-control strategy is presented to enhance the reliability of the system. Experimental results illustrate the effectiveness and practicability of the proposed inverter scheme and the position sensorless control method.

一种基于ARM + CPLD的三相无刷直流电机模型参考自适应PI调速控制系统

本文设计并开发了一种基于ARM + CPLD的三相无刷直流电机模型参考自适PI调速控制系统：由CPLD芯片实现无刷直流电机的换相与方波驱动、快速故障保护，兼具电机转子机械转速实时测量功能；由ARM芯片实现模型参考自适应PI控制算法。ARM与CPLD之间通过SPI总线接口实现全双工通信，两块芯片联合工作实现电机转速的精确控制。通过Simulink仿真和实际试验，验证了该驱动控制系统硬件结构和控制算法的有效性。采用的模型参考自适应PI控制算法，提高了无刷直流电机闭环负反馈控制的鲁棒性，使得电机参数或者电机负载发生变化时，在不重新整定PI参数的前提下，闭环控制系统依然能够保持良好的控制性能。 A three-phase brushless DC Motor (BLDCM) speed control system is designed and developed by using ARM and CPLD: motor drive commutation, square wave drive, fast fault protection and motor speed measurement logic being realized by CPLD chip; model reference adaptive PI control algorithm is implemented by ARM chip. Full duplex communication between ARM and CPLD is conducted over SPI bus interface. Precise control of motor speed is achieved by two chips’ joint work. The effectiveness of the control system structure and control algorithm was tested through Simulink simulation and actual experiment. Model reference adaptive PI algorithm improved the robustness of the BLDCM closed loop feedback control system. Consequently, when the motor pa-rameter or the motor load changes, without adjusting PI parameters, the closed-loop control system is still able to maintain excellent control performance.

High-Precision Speed Control Based on Multiple Phase-Shift Resonant Controllers for Gimbal System in MSCMG

The high precision speed control of gimbal servo system in magnetically suspended control moment gyro (MSCMG) suffers from periodic torque disturbances, which lead to periodic fluctuations in speed control. This paper proposes a novel multiple phase-shift resonant controller (MPRC) for a gimbal servo system to suppress the periodic torque ripples whose frequencies vary with the operational speed of the gimbal servo motor and high-speed motor. First, the periodic torque ripples caused by cogging torque, flux harmonics and the dynamic unbalance of the high speed rotor are analyzed. Second, the principle and structure of MPRC parallel with proportional integral (PI) controllers are discussed. The design and stability analysis of the proposed MPRC plus PI control scheme are given both for the current loop and speed loop. The closed-loop stability is ensured by adjusting the phase in the entire operational speed range. Finally, the effectiveness of the proposed control method is verified through simulation and experimental results.

Modeling and Three-Layer Adaptive Diving Control of a Cable-Driven Underwater Parallel Platform

This paper focuses on the modeling, diving controller design, and experiment of a special cable-driven underwater parallel platform with eight-cable coupling drive structure. Kinematic and dynamic models of the platform are established utilizing a simplified approach, and the hydraulic driven control model is derived based on joint-space method. To improve the diving control precision and system robustness despite the complex dynamic behaviors and manifold unknown disturbances, a three-layer adaptive diving control strategy is proposed. Among the three control layers, layer 1 is responsible for dive planning and online monitoring, layer 2 places emphasis on synchronous control by employing an improved relative coupling strategy, layer 3 utilizes an adaptive radial basis function neural network-based backstepping sliding mode control algorithm (ARBFNN-BSMC) to achieve high precision speed control of the single driving branch. Hardware-in-the-loop simulations and experimental results illustrate that the proposed three-layer adaptive diving control strategy can asymptotically drive the cable-driven underwater parallel platform onto a predefined diving trajectory with favorable precision, robustness, and stability.

Model Predictive Engine Speed Control for Transmissions With Dog Clutches

The need for cost-effective fuel economy improvements has driven the introduction of automatic transmissions with an increasing number of gear ratios. Incorporation of interlocking dog clutches in these transmissions decreases package space and increases efficiency, as compared to conventional dry or wet clutches. Unlike friction-based clutches, interlocking dog clutches require very precise rotational speed matching prior to engagement. Precise engine speed control is, therefore, critical to maintaining high shift quality. This research focuses on controlling the engine speed during a gearshift period by manipulating throttle position and combustion phasing. Model predictive control (MPC) is advantageous in this application since the speed profile of a future prediction horizon is known with relatively high confidence. The MPC can find the optimal control actions to achieve the designated speed target without invoking unnecessary actuator manipulation and violating hardware and combustion constraints. This research utilizes linear parameter varying (LPV) MPC to control the engine speed during the gearshift period. Combustion stability constraints are considered with a control-oriented covariance of indicated mean effective pressure model (COV of IMEP). The proposed MPC engine speed controller is validated with a high-fidelity zero-dimensional engine model with crank angle resolution. Four case studies, based on simulation, investigate the impact of different MPC design parameters. They also demonstrate that the proposed MPC engine controller successfully achieves the speed reference tracking objective while considering combustion variation constraints.

FOC of SRM using More Efficient DC-DC Converter Topology

<p>Numerous studies had been made to improve the switched reluctance motor operation depend on the modification of the machine design, proposing the converter designs and/or applying a suitable control method. This paper introduces the field orientation control method for that motor using a simple and very efficient DC-DC converter topology. This control method is presented by two techniques; first technique is the advance of the turn-on switching angle and the other technique is the retard/delay of the turn-off switching angle. Instantaneous and average motor characteristics are obtained using Matlab/Simulink software package. Comparison between the simulation results presented using two converter types. A precise speed and torque control are obtained. The average total torque per current is maximized.</p>

Design and application of a novel high precision and low cost electronic tachogenerator for sensor-based brushless direct current motor drivers.

This study presents a precise speed control method for Brushless Direct Current (BLDC) Motors using an electronic tachogenerator (ETg) instead of an electro-mechanical tachogenerator. Most commonly used three-phase BLDC motors have three position sensors for rotor position data to provide commutation among stator windings. Aforementioned position sensors are usually Hall-effect sensors delivering binary-high and binary-low data as long as the motor rotates. These binary sets from three Hall-effect sensors can be used as an analogue rotor speed signal for closed loop applications. Each position sensor signal is apart from 120 electrical degrees. By using an electronic circuitry, a combination of position sensor signals is converted to the analogue signal providing an input to a PI speed controller. To implement this, a frequency to voltage converter has been used in this study. Then, the analogue speed signal has been evaluated as rotor speed data in comparison with the reference speed. So, an ETg system has been successfully achieved in place of an electro-mechanical tachogenerator for BLDC motor speed control. The proposed ETg has been tested under various speed conditions on an experimental setup. Employed tests and obtained results show that the proposed low-cost speed feedback sub-system can be effectively used in BLDC motor drive systems. Through the proved method and designed sub-system, a new motor controller chip with a speed feedback capability has been aimed.

Instrumented Soil Bin for Testing Soil-Engaging Tools

Abstract. An indoor soil bin was developed in this study for testing soil-engaging tools. The design criteria included that the soil bin had to be compact, well controlled in its operational parameters, instrumented to measure soil cutting forces, and be safe to operate. The test tool could travel at any specific speed, up to 8 km h-1. A compact dynamometer was designed for the soil bin for measuring soil cutting forces in three directions. The calibration results of the dynamometer showed a linear relationship between the loads and the output voltages, with coefficients of determination of 0.99. The cross sensitivity between the directions was from 0.31% to 4.7%. The soil bin and the dynamometer were tested using a disc operated at three values of tilt angle of 0°, 10°, and 20°. The test results showed that the soil bin allowed precise control of the tool travel speed and working depth in the designed ranges. Forces of the disc had an increase in vertical and lateral forces, and decrease in draft force, with the increase in tilt angle. These trends are in line with other studies in the literature. The results proved the full-functioning status of the soil bin and the dynamometer. Keywords: Calibration, Design, Disc, Dynamometer, Soil bin, Test, Tilt angle.

Examining the Effect of Age on Visual-Vestibular Self-Motion Perception Using a Driving Paradigm.

Previous psychophysical research has examined how younger adults and non-human primates integrate visual and vestibular cues to perceive self-motion. However, there is much to be learned about how multisensory self-motion perception changes with age, and how these changes affect performance on everyday tasks involving self-motion. Evidence suggests that older adults display heightened multisensory integration compared with younger adults; however, few previous studies have examined this for visual-vestibular integration. To explore age differences in the way that visual and vestibular cues contribute to self-motion perception, we had younger and older participants complete a basic driving task containing visual and vestibular cues. We compared their performance against a previously established control group that experienced visual cues alone. Performance measures included speed, speed variability, and lateral position. Vestibular inputs resulted in more precise speed control among older adults, but not younger adults, when traversing curves. Older adults demonstrated more variability in lateral position when vestibular inputs were available versus when they were absent. These observations align with previous evidence of age-related differences in multisensory integration and demonstrate that they may extend to visual-vestibular integration. These findings may have implications for vehicle and simulator design when considering older users.

Focused Ion Beams for Lithiation of High Capacity Host Materials for Negative Electrodes

High capacity negative electrode Li ion battery materials such as Sn and Si are attracting great attention as higher capacity replacements for conventional graphite-based electrodes. Although they are very attractive materials in terms of their theoretical capacity (993 mAh/g for Sn and 4200 mAh/g for Si), and are nontoxic and naturally abundant, the challenges lie in their huge volume expansion and subsequent cracking, pulverization and electrochemical degradation [1]. Atomic level structural studies of lithiated nanostructured Sn- and Si-based electrodes using transmission electron microscopy (TEM), synchrotron radiation, X-ray diffraction (XRD), neutron diffraction and other instrumental methods under static conditions and in siturepresent an important approach for understanding the mechanisms of ion transport and associated volume expansion and cracking of the prospective host materials [2,3]. However, in these methods, multi-step phase transformations during lithiation involving cracking are only observed together with the transformations and movements of interfaces and boundaries of various expanding lithiated phases. To discern the various processes, it is necessary to have efficient control of the lithiation kinetics and the quantities of the transformed material. Techniques that enable the probing of lithiation at the nanoscale are critical for deeper insights into the complex mechanisms of lithiation processes and phase transformations of the host electrode materials. We introduce focused low-energy Li-ion beam (Li-FIB) as a new tool for direct lithiation of Sn and Si-based host materials with precise control of the lithiation speed as well as location and size of the chosen area [4]. In the Li-FIB, a focused beam with spot size of order 50 nm is scanned in a pattern across the sample. The rate of Li-ion injection (in the range of 5×106 ion·μm-2 s-1 for this measurement) can be controlled by adjusting the beam current (I ≈ 1 pA), and the area of lithiation can be precisely defined over a wide range, up to several micrometers, by controlling the scan pattern. Unlike with electrochemical lithiation, a solid electrolyte interface (SEI) is not formed with Li-FIB lithiation since the process takes place in a vacuum of ~2×10-4Pa. This enables us to study solely the structural evolution and associated stress accumulation in the host materials without any influence from the formation of the SEI. As an initial study, we compared Li-FIB lithiation with conventional electrochemical methods. The electrochemical lithiation was carried out in a three electrode cell with Li metal foil used for counter and reference electrodes. The electrolyte was composed of 1 mol dm-3 LiClO4in a mixture of ethylene carbonate (EC): diethyl carbonate (DEC) (1:1 by volume). The processed electrodes were washed with dimethyl carbonate (DMC) after lithiation and could be transferred for further TEM examination in a glove bag purged with Ar to prevent air exposure. To analyze the nanoscale morphological, crystallographic and compositional differences in the host materials lithiated by the two different methods, we employed Ga+ ion beam cross sectioning and field-emission scanning electron microscopy (FESEM). In this talk, we will compare a few models of Sn and Si electrodes lithiated with Li-FIB and electrochemically. For single crystalline β-Sn microspheres deposited onto a hard carbon substrate, the results are shown in Fig. 1. Figure 1 shows cross-sectioned Sn samples of (a) lithiated Sn with Li-FIB and (b) electrochemically lithiated Sn. The surface roughness in Fig. 1(a) indicates the volume expansion of Sn due to lithiation. In Fig. 1(b), non-uniform corrugations were observed on the surfaces of electrochemically lithiated electrodes, which may be caused by volume expansion and SEI formation during processing in the organic electrolyte. We think the band contrasts in Fig. 1 are associated with lithiated volume, since no contrast was observed for unlithiated spheres. It is interesting to note that the distribution of the band of contrast is different in Fig. 1 (a) and (b). The obtained results indicate that nanoscale processes that occur during Li+implantation involve a series of overlapping physico-chemical transformations, which will be discussed in more details in the talk. [1] D. Ma et al, Nano-Micro Lett.(2014) 347. [2] M. T. Janish et al, J. Mater. Sci., 51 (2016) 589 [3] X. H. Liu et al, Nat. Nanotechnol. 7 (2012) 479. [4] S. Takeuchi et al, J. Electrochem. Soc., 163 (2016) A1010 Figure 1

Precise PI speed control of permanent magnet synchronous motor with a simple learning feedforward compensation

This paper develops a precise proportional–integral (PI) type control system for repeatable tracking control of a permanent magnet synchronous motor (PMSM) under motor parameter and load torque variations. By adding a very simple learning feedforward term, a conventional PI control system can be enforced to have a perfect tracking performance under model parameter and load torque variations. The convergence and stability of the closed-loop control system response are analytically shown. Finally, the simulation and experimental results are given to verify the effectiveness of the proposed PI-type learning control law under the uncertainties such as motor parameter and load torque variations using a prototype PMSM drive system.

Optimization of a Neurotoxin to Investigate the Contribution of Excitatory Interneurons to Speed Modulation In Vivo

Precise control of speed during locomotion is essential for adaptation of behavior in different environmental contexts [1-4]. A central question in locomotion lies in understanding which neural populations set locomotor frequency during slow and fast regimes. Tackling this question invivo requires additional non-invasive tools to silence large populations of neurons during active locomotion. Here we generated a stable transgenic line encoding a zebrafish-optimized botulinum neurotoxin light chain fused toGFP (BoTxBLC-GFP) to silence synaptic output over large populations of motor neurons or interneurons while monitoring active locomotion. Bycombining calcium imaging, electrophysiology, optogenetics, and behavior, we show that expressionof BoTxBLC-GFP abolished synaptic release while maintaining characterized activity patterns and without triggering off-target effects. As chx10(+) V2a interneurons (V2as) are well characterized as the main population driving the frequency-dependent recruitment of motor neurons during fictive locomotion [5-14], we validated our silencing method by testing the effect of silencing chx10(+) V2as during active and fictive locomotion. Silencing of V2as selectively abolished fast locomotor frequencies during escape responses. In addition, spontaneous slowlocomotion occurred less often and at frequencieslower than in controls. Overall, this silencing approach confirms that V2a excitation is critical for the production of fast stimulus-evoked swimming and also reveals a role for V2a excitation in the production of slower spontaneous locomotor behavior. Altogether, these results establish BoTxBLC-GFP as an ideal tool for invivo silencing for probing the development and function of neural circuits from the synaptic to the behavioral level.

Precise velocity control of a bipedal robot using CPG circuits in creating different behaviors

In this paper, we have extended our previous work, which created several motion phases in running and walking movements with a central pattern generator (CPG) model, to controlling the robot’s walking speed easily and precisely within a wide speed range to investigate the possibility of CPG in the domain of bipedal robotic locomotion. Our method proposed herein basically used our hybrid CPG (H-CPG) model. This model consisted of a rhythm generator using CPG, a force controller, and an attitude controller. We have also introduced a modulation mechanism using a velocity feedback loop in this force controller for the precise control of acting forces from the tip of the support leg to the floor and the walking stride length. This mechanism can realize accurate modulation of the walking velocity reflecting an error between the target velocity and the current velocity in real time. Numerical simulation results show the effectiveness of the proposed method for realizing precise control of the locomotion speed in both backward and forward stable walking.

Assessing drivers’ visual-motor coordination using eye tracking, GNSS and GIS: a spatial turn in driving psychology

Vehicle-driving in real traffic can be considered as a human-machine system involving not only the attribute of the vehicle movement but also the human visual perception, cognition and motion of the driver. The study of driving behaviours, therefore, would integrate information related to driver psychology, vehicle dynamics and road information in order to tackle research questions concerning driving safety. This paper describes a conceptual framework and an integrated GIS data model of a visual-motor coordination model (VMCM) to investigate drivers’ driving behaviour via the combination of vision tracking and vehicle positioning. The eye tracker recorded eye fixations and duration on video images to exhibit the driver’s visual search pattern and the traffic scenes. Real-time kinematic (RTK) post-processing of multi-GNSS (global navigation satellite system) tracking generated the vehicle movement trajectory at centimeter-level accuracy, which encompasses precise lateral positioning and speed control parameters of driving behaviours. The eye fixation data were then geocoded and linked to the vehicle movement trajectory to represent the VMCM on the GIS platform. An implementation prototype of the framework and the VMCM for a study of older drivers is presented in this paper. The spatial-temporal visualisation and statistical analysis based on the VMCM data-set allow for a greater insight into the inherent variability of older drivers’ visual search and motor behaviours. The research framework has demonstrated a discriminant and ecologically valid approach in driving behaviour assessment, which can also be used in studies for other cohort populations with modified driving scenarios or experiment designs.

Speed Control of Vane-Type Air Motor Servo System Using Proportional-Integral-Derivative-Based Fuzzy Neural Network

A novel proportional-integral-derivative-based fuzzy neural network (PID-based FNN) controller is proposed in this study to control the speed of a vane-type air motor (VAM) servo system for tracking periodic speed command. First, the structure and operating principles of the VAM servo system are introduced. Then, the dynamics of the VAM servo system is analyzed to derive the second-order state equation of the VAM. Moreover, due to the dynamic characteristics and system parameters of the VAM servo system are highly nonlinear and time-varying, a PID-based FNN controller, which integrates conventional proportional-integral-derivative neural network (PIDNN) control with fuzzy rules, is proposed to achieve precise speed control of VAM servo system under the occurrences of the inherent nonlinearities and external disturbances. The network structure and its on-line learning algorithm using delta adaptation law are described in detail. Meanwhile, the convergence analysis of the speed tracking error is given using the discrete-type Lyapunov function. To enhance the control performance of the proposed intelligent control approach, a 32-bit floating-point digital signal processor (DSP), TMS320F28335, is adopted for the implementation of the proposed control system. Finally, experimental results are illustrated to show the validity and advantages of the proposed PID-based FNN controller for VAM servo system.

Sistemas Integrados de Potencia en Buques Offshore: Control, tendencias y retos

The offshore vessels require a high precision speed control and dynamic positioning. Adverse weather conditions and/or rough waves give rise to high disturbances that must be rejected by the control system to keep the vessel position in the area or station where the vessel operation is being executed. Other requirements related to the safety, reliability and robustness must be obviously ensured. Since more than a decade the power system of this kind of vessels is based on a diesel-electric power plant where the propellers and thruster units are controlled by electrical drives. In this power system the required electrical energy/power is generated through diesel gensets, and distributed to the propulsion drives (and to the rest of vessel utility loads) through a power grid. In this work the most commonly used integrated power system architecture is first introduced thus identifying the control functions and their interdependencies. Some trends and new power system topologies to improve the energy efficiency are then also presented and described. The emergence of new solutions based on DC grids allows the diesel gensets to operate at variable speed and makes the integration of the energy storage systems or even some renewable energy systems easier. However, they present some technical and design challenges in order to ensure a stable and robust solution by design. One of them is related to the stability analysis of the DC grid when multiple nonlinear constant power loads (negative impedance) are connected and thus interacting on the same DC bus.

Embedded two level direct adaptive fuzzy controller for DC motor speed control

Abstract This paper presents a proposed approach based on an adaptive fuzzy logic controller for precise control of the DC motor speed. In this concern, the proposed Direct Adaptive Fuzzy Logic Controller (DAFLC) is estimated from two levels, where the lower level uses a Mamdani fuzzy controller and the upper level is an inverse model based on a Takagi–Sugeno (T–S) method in which its output is used to adapt the parameters of the fuzzy controller in the lower level. The proposed controller is implemented using an Arduino DUE kit. From the practical results, it is proved that the proposed adaptive controller improves, successfully both the performance response and the disturbance due to the load in the speed control of the DC motor.