Trapezoidal Control Research Articles

A Review of System for Recommending Jobs Using Machine Learning

Brushless direct current (BLDC) motors are frequently used in dynamic applications. A Brushless DC Motor is similar to a Brushed DC Motor, except that as the names indicate, they are electronically commutated rather than using brushes for commutation. Brushes are utilized in conventional brushed direct current motors to transmit power to the rotor while they rotate in a fixed magnetic field. Small Brushless DC Motors have flourished as a result of current power electronics and microprocessor technology, both in terms of price and performance. This paper will discuss the history of BLDC motors, their different types, construction, operating principles, and several control mechanisms for driving BLDC motors in various industrial applications. Keywords: BLDC Motor, Pulse Width Modulation (PWM), Hall Effect Sensors, Sensorless control, Rotor, Stator, Back Emf, Trapezoidal Control, Sinusoidal Control, Field Oriented Control

Iron Loss Analysis in Axial Flux Permanent Magnet Synchronous Motors With Soft Magnetic Composite Core Material

Accurate calculation of iron losses in electric machines are essential for optimal machine design. This is especially important for axial flux permanent magnet motors with solid stator and rotor cores. This paper investigates iron losses in axial flux motor with soft magnetic composite material for the stator and the rotor. First, an analytical model is proposed to estimate iron losses under different operating conditions. The model is based on combining the Quasi 3-D computation approach and the magnetic equivalent circuit. The proposed model can be modified to account for different motor topologies and different stator and magnet designs. Then, The effect of torque ripple, on iron losses, is studied by comparing two motors: an optimized motor, with dummy pocket added to the stator tooth, and a non-optimized motor. Finally, the effect of the motor control scheme and the inverter switching frequency is studied by implementing two controllers: the Field Oriented Control and the Trapezoidal control. Simulations using 3-D finite element analysis and experimental tests are conducted, under different operating conditions, on two <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{12}\,V$</tex-math></inline-formula> , 6 slots, 8 poles single stator single rotor fractional horsepower axial flux permanent magnet synchronous motor prototypes. Test results shows that motor optimization, the choice of the motor control scheme, and the selected switching frequency can significantly affect iron losses in the motor. Using an optimized motor with a smooth control scheme, such as Field Oriented Control, and a high switching frequency, can cause a variation in iron losses by around 14% compared to a non optimized motor with the Trapezoidal control and a low switching frequency.

A fuzzy rule based control algorithm for MPPT to drive the brushless dc motor based water pump

In this paper, a solar photovoltaic model integrated with brushless DC motor via DC to DC zeta converter is controlled in two stage. In first stage, a fuzzy rule based maximum power point tracking (PPT) is proposed to generate the pulse for DC to DC zeta converter. It is efficient intelligent control approach to extract maximum power from the solar PV system and enhance the speed to track the maximum power. The basic three process of fuzzy logic controller (FLC) are fuzzifier, inference and defuzzifier where the defuzzification process is used center of gravity (COG) method to convert its original value. The FLC to extract maximum PPT for solar PV based brushless DC motor can be examined the performance under transient and dynamic condition with different solar insolation. Moreover, in second stage a trapezoidal control approach based electronic commutation is chosen to generate the pulses of voltage source inverter (VSI) and it offers the smooth control of the brushless DC motor which can easily applicable for water pumping or irrigation purpose. A second stage, trapezoidal control approach is close loop control algorithm using sensorless drive. The performance of proposed fuzzy rule based control algorithm is shown using simulation results on MATLAB platform.

Impact of the load angle on magnetic radial pressure and torque ripple of a low power PMSM with trapezoidal control

PurposeThis paper deals with the study of the influence of the phase shift between currents and back-electromotive forces (back-EMF) on torque ripple and radial magnetic forces for a low power synchronous machine supplied with 120 degrees square-wave currents. This paper aims to establish a good compromise between efficiency, harmonics of torque and harmonics of radial forces at the origin of the electromagnetic noise.Design/methodology/approachBased on a finite element approach, torque and magnetic pressure harmonics versus space and frequency are evaluated for different angle values. The evolutions of the different harmonics against the load angle are analyzed and compared to those of experimental measurements.FindingsDepending on the load torque, field-weakening or field-boosting can be used to reduce current harmonics contributing the most to the radial magnetic forces responsible for the noise. Besides, a compromise can be found to avoid deteriorating too much the performances of the machine, thus being suitable with an industrial application.Research limitations/implicationsThis study concerns low power permanent magnet synchronous machines with concentrated windings and driven with a trapezoidal control, while having sinusoidal back-EMF.Originality/valueThe use of a simple mean and suitable with a large-scale manufacturing industry to reduce the identified electromagnetic-borne noise of a specific electric drive makes the originality.

Field Oriented Control-Based Reduction of the Vibration and Power Consumption of a Blood Pump

Power quality and energy efficiency are of great importance in motor control. The motor of any medical device needs to have a smooth torque and minimal vibration in order to maximise its energy efficiency and patient comfort. Furthermore, in rotary blood pumps, excessive energy wasted due to vibration is converted into uncontrolled movement of the mechanical parts and thus could reduce the life of the motor-pump. Besides mechanical or hydraulic origin, one of the causes of vibration in any pump is torque ripple resulting from motor phase commutation. In this paper, using relevant equipment, two extreme scenarios were examined for vibration and electrical efficiency comparison due to power quality in a blood pump: one trapezoidal control with a trapezoidal phase current output; the other a field oriented control (FOC) with a non-distorted sinusoidal phase current. The test motor-pump was the Arteriovenous Fistula Eligibility (AFE) System that is used prior to haemodialysis. The trapezoidal technique was implemented utilising the Allegro a4941 fan driver (Allegro Microsystem, 2012), and the FOC technique was implemented using the Texas Instrument digital signal processor (TMS320F28335). The aim was to reduce the energy wasted over vibration, and to achieve smooth operation of the AFE System. Vibration was measured with a one-axis accelerometer; results showed considerably lower vibration due to less current ripple associated with the FOC control as well as lower power consumption.

Dynamic Behaviour of Spindle on Large EDM Machine Induced by High-Speed Jump Motion with Different Control Strategies

High-speed jump motion in electrical discharge machining (EDM) has been proven to be an important reason for flexible impact and vibration on EDM machine tools. Especially for large EDM machines, the moving parts possess large mass, and different jump control strategies cause different vibration characteristics. However, little attention has been paid to the kinematic comparison between different strategies, and the effect of jump motion on EDM spindle dynamics behaviour is also neglected. In this paper, the dynamic behaviour of spindle on a large EDM machine induced by high-speed jump motion has been investigated. Control strategies including trapezoidal velocity profile, constant jerk profile and sinusoidal jerk profile are considered. The kinematic characteristics of these jump control strategies and corresponding dynamic behaviour of EDM spindle were studied. As a result, under the same maximum velocity of 80 mm/s and maximum jerk of 128 m/s3, the jump period and height of sinusoidal jerk profile are about 0.05 s longer and 1.2 mm larger than that of the other two strategies, respectively. Trapezoidal control strategy causes the largest vibration amplitude of 48.7 μm on spindle during jump motion and thus the strongest forced vibration. The experimental measurement platform for vibration displacement was established. Comparing simulation and experiment data, the relative error is lower than 14%, which verifies the simulation model. Moreover, it can be found that large jump velocity increases vibration amplitude of spindle significantly during machining. When the velocity is 80 mm/s, the maximum vibration amplitude is 23.0 μm. And large velocity of jump motion makes spindle amplitude attenuate faster.

Design and Performance Analysis of Brushless Direct Current (BLDC) Motor Controller for Electric Scooter

Electric vehicle is an alternative to substitute internal combustion engine when fuel availability is difficult to obtain. Electric energy can be obtained from renewable energy and non-renewable energy. Electric vehicles like electric scooters consist of many parts. The parts used in an electric scooter have requirements such as reliability, safety, good performance, and high efficiency. Brushless direct current (BLDC) motor controller is one of the main components in the electric scooter. This paper presents a design and performance test of the BLDC motor controller. The controller uses PID current control with six step commutation in a trapezoidal control. The motor current ripple is eliminated by using a digital isolator. Tests were carried out using an Eddy Current Dynamometer. The results show that the current ripple is sucessfuly reduced which makes the controller suitable for electric scooter applications.

Adaptive fourier series speed controller for permanent magnet synchronous motor and brushless dc motor

Permanent magnet motors provide the highest power density and highest efficiency among all types of electric motors. For machine tool components and fast dynamic positioning systems the PMSM motors are commonly used. On the other hand, the BLDC motor delivers a higher torque to size ratio compared to DC motors, making it suitable for applications where weight and space are important factors. The construction of PMSM and BLDC motors is similar. However, they require completely different control approach, (Field Oriented Control for PMSM and Trapezoidal Control for BLDC). In this paper a new adaptive controller for PMSM and BLDC motors is proposed. For this controller a trapezoidal control is implemented and the torque ripple (due to non-trapezoidal back-EMF), is reduced using a Fourier series approach. The proposed controller was implemented experimentally and the results confirm it is effective to reduce the effect of internal torque ripple as well as the speed ripple produced by external periodic torque disturbances applied to the PMSM. Using the Adaptive Fourier Series Controller, the reduction on speed ripple was 2.7% of nominal speed when the first four terms of Fourier series were used, while the standard Field Oriented Control produced a speed ripple of 112% of the nominal angular speed.

Implementation of a three-phase inverter with trapezoidal control for a BLDC motor with educational purpose

Implementation of a three-phase inverter with trapezoidal control for a BLDC motor with educational purpose

Sensorless Vector Controlled Multilevel Inverter Fed BLDC Motor

BLDC motors are mostly known to be driven by trapezoidal control due to its simple implementation, but this type of control results in pulsating torque ripple which is unwanted in high performance drives. In this paper, vector control is combined with a five-level inverter to minimize the torque ripple of BLDC motor in sensorless operation as well as reducing the total harmonic distortion in the voltage and current waveforms. The MATLAB/Simulink environment is used to simulate and verify the proposed method.

Trapezoidal Control of a Coiled Synchronous Motor Optimizing Electric Vehicle Consumption

In this paper, we present a systemic trapezoidal control methodology of a coiled rotor axial flux synchronous motor dedicated to electric traction, taking into account of several constraints such as the speed limit, the energy saving, the cost of the power chain and the reliability of the whole system. Indeed the control law developed allows to impose the electromotive forces in phase with the phase currents, which reduces vehicle consumption. Also based on the technique of overfluxing during periods of high acceleration to reduce the phase current of the motor and then the vehicle consumption. This optimization technique is based on the increase of the excitation current for a given torque, thereby increasing the electric motor constant. Therefore, the phase current is lowered leading to a reduction in consumption. During the phases of constant speed operation and high decelerations, the value of the excitation current is calculated iteratively to minimize the consummation. Finally, the results obtained are with good level which encourages the electronic integration phase of this control law.

Trapezoidal Control Integrating the Losses of an Electric Car Power Train

In this paper, we present a modeling approach of the power chain based on the trapezoidal control, including the losses of the power train of an electric car. This modeling approach is parameterized leading to a problem of optimization of the parameters influencing the losses which leads to an improvement in the autonomy. This model approach is implanted under the simulation environment Matlab-Simulink. Simulation results are encouraging and opening track search for work optimization and experimental validation of the developed model.

Wireless CNC Motion Controller Designed with PSoC

Numerical control (NC) technology is a kind of technology combined with electronics, machinery manufacturing, and other interdisciplinary combination of technologies. It is an important part of modern manufacturing. Currently, NC technology is developing towards the open CNC system with extensibility and interchangeability, while the modern electronic technology is developing towards the programmable technology and SoC (System-on-Chip) technology. However, current CNC controller designed with SoC is still in the research stage and not practical yet. In this paper, a practical CNC motion controller is built with modern PSoC (Programmable System-on-Chip) with wireless Ethernet interface. This controller has a high-performance microprocessor, numbers of free configurable analog and digital devices and IO (input/output) interfaces, and many kinds of communication interfaces. Therefore, it has good real-time control functions and communication functions. Experiments for controlling a three joint-axis engraving machine show that the controller can achieve high performance of parallel control of the three joint-axis linear interpolation and two joint-axis circular interpolation, and high performance of the trapezoidal and S-shape speed control. In addition, in order to reduce the impact to the motor and increase the system efficiency, a kind of look-ahead algorithm for velocity control with low time cost is used.

Limiting dimensions for trapezoidal channels and control notches (Design Aid)

Determining the channel dimensions leading to critical flow conditions for given values of specific energy or specific force plays an important role in channel transition design. A closed-form analytical solution for the problem can only be derived for triangular, rectangular and parabolic channels. This is not possible, however, for other practical geometries, such as trapezoidal channels. The dimensions of the trapezoidal control notch are determined by simultaneously satisfying the critical state of flow and specific energy equation. At present, graphical solutions are used for design discharges less than 2.83 m3/s. In current study, direct solutions to compute the limiting dimensions of the trapezoidal channel and direct solutions to design of the trapezoidal control notch are derived. The proposed solutions are nearly exact and will be useful in the design and analysis of the trapezoidal channels and notches.

Grounding the figure: Surface attachment influences figure-ground organization

We investigated whether the lower region effect on figure-ground organization (Vecera, Vogel, and Woodman, 2002) would generalize to contextual depth planes in vertical orientations, as is predicted by a theoretical analysis based on the ecological statistics of edges arising from objects that are attached to surfaces of support. Observers viewed left/right ambiguous figure-ground displays that occluded middle sections of four types of contextual inducers: two types of attached, receding, vertical planes (walls) that used linear perspective and/or texture gradients to induce perceived depth and two types of similar trapezoidal control figures that used either uniform color or random texture to reduce or eliminate perceived depth. The results showed a reliable bias toward seeing as "figure" the side of the figure-ground display that was attached to the receding depth plane, but no such bias for the corresponding side in either of the control conditions. The results are interpreted as being consistent with the attachment hypothesis that the lower region cue to figure-ground organization results from ecological biases in edge interpretation that arise when objects are attached to supporting surfaces in the terrestrial gravitational field.