Three-phase AC Motor Research Articles

Design and Application Prototype of soft starting Three-Phase AC Motor by Using Analog Electronics Control for Teaching Aids of Power Electronics Practice

In general, palm oil processing factories, from fresh fruit bunches to Crude Palm Oil, require three-phase electric motors to drive or rotate it. The problems that often arise when using three-phase electric motors simultaneously in large numbers will result in very large surges in the electric current, which can affect the performance of electronic devices. To overcome this problem, a prototype of a three-phase AC voltage regulator circuit was made by adjusting the SCR triggering delay angle using an analog electronics equipment control that can be used for three-phase motor soft start applications in a palm oil factory. This prototype will be used as a learning tool for the practical for Aceh Polytechnic students for power electronics courses. This system is built with a method where the three-phase source is first lowered using a transformer arranged in a star on the primary and secondary sides, then each voltage is compared to the ground using an IC LM324, which aims to produce pulses wave. This pulse then connected to a triangular wave generator circuit, this triangular wave is then compared with the DC source voltage from the potentiometer, which aims to regulate the SCR triggering angle of SCR via MOC3063 driver, where the load used is resistive and connected in a star. The measurement using an oscilloscope and observing the change of triggering angle for several variations of each phase, the different Vrms voltage between measurements compared to mathematical analysis influenced by several factors, including, the transformer is made of three transformers that not identically, the electronic components used are not in ideal condition, and observations on the oscilloscope are carried out visually using the eye and manually adjusting the potentiometer rotation so that the level of measurement accuracy between one person and another will produce different values.

Review of Switched Reluctance Motor Converters and Torque Ripple Minimisation Techniques for Electric Vehicle Applications

This paper presents a review of the most common power converters and torque ripple minimisation approaches for switched reluctance motors (SRMs). Unlike conventional three-phase AC motors, namely squirrel cage induction motors and permanent magnet synchronous motors, which require a typical three-phase inverter for operation, the switched reluctance motor requires a different topology power converter for reliable and efficient operation. In addition, due to the non-linear, discrete nature of SRM torque production, torque ripple is severely pronounced, which is undesirable in servo applications like electric vehicles. Hence, deploying a proper torque control function for smooth and quiet motor operation is crucial. This paper sheds light over the most popular SRM power converters as well as torque ripple minimisation methods, and it suggests an optimal SRM drive topology for EV applications.

50 YEARS FIELD ORIENTED CONTROL OF THREE-PHASE AC DRIVES IN THE PRACTICE - THE STATE OF THE ART

From DC motors (DCM) we know, it is possible to independently control the two currents of the flux and torque generating. Because the two DCM circuits are completely isolated, we obtain simple adjustment algorithms that require little computing time on the microprocessor. For this reason, DCM has been at the forefront of the application of digital controls in drive control systems in the early years, especially in high-performance systems. On the contrary, the three-phase AC motor (ACM) has a complex structure due to the winding system and three-phase power supply, and has caused significant difficulties in the mathematical description of the above decoupling characteristics. The purpose of the field-oriented control (FOC) is therefore to create a tool that allows the decoupling control of the flux and torque-producing current components from the three-phase AC currents flowing in the coil. The FOC drive system is a system based on the principle of decoupling the above power components thanks to the stator current feedback control (the innermost circuit of the drive system). The FOC-type control method belongs to the class of vector control methods for electrical machines. On the occasion of the 50th anniversary of FOC, this paper aims to provide an overview of the development status of FOC in industrial practice. The content presented deals mainly with 3-phase induction motors.

A new AC motor driven by travelling magnetic field excited on LC ladder circuit without its nonlinearity

In three-phase AC motors, three-phase AC voltage system is essential to generate a rotating magnetic field. Three- phase AC motors also require a three-phase inverter for variable speed and torque operation. In general, the number of switching devices used in three-phase inverter is not less than six and decreasing its number is difficult. This paper focuses on an LC ladder circuit consisting of linear inductors and capacitors. This paper presents a new operating method of the AC motor based on a propagating magnetic field. It is successfully excited by connecting one single-phase AC power supply to the end of the LC ladder circuit. The induction motor operated by the presented method produces torque as in general induction motors.

Computational Comparison of AC and DC Motors to Hydrodynamic Changes in Marine Fishing Vessels

The objective of this article is to make a comparison in a computational environment between an alternating current motor and a direct current motor is made for dynamic variations in the propulsion of an artisanal fishing boat. Initially, the boat was simulated in the Maxsurf software to obtain the dynamic behaviors for pitching, rolling, yawing, and heave motions with wind and wave perturbations for a Pierson Moskowitz spectrum. Subsequently, the motors are selected and in Matlab/Simulink software and a torque behavior required by the vessel to act on the resistance presented in each dynamic motion is proposed. This allows for analyzing the required mechanical and electrical conditions, using the curves obtained in the simulation. Finally, it is concluded that taking into account the criteria of torque, power, speed, and current, the results obtained show that the DC motor is more efficient than the three-phase AC motor for artisanal fishing vessel applications. In addition, the two motors require greater effort to overcome the disturbance related to the rolling motion in the steady-state, while in the transient state the DC motor requires a higher starting torque and the AC motor presents oscillations, which are undesirable disturbances because they produce instability in the electrical system. Additionally, it is important to take into account the energy source that feeds the motors, which can be alternating current or direct current.

Comparative study of frequency converters of three-phase electric motors in automatic control of technological parameter

Frequency converters of asynchronous three-phase AC motors are widely used in industry, including food production. A thorough understanding of the technical capabilities of frequency converters contributes to their efficient use. This article discusses a technical comparison of two frequency converters of three-phase electric motors of the Russian company "OWEN" and the Danish company "DANFOSS" according to the criterion of the quality of regulation of the technological parameter. For comparison, a test bench was created, in which the devices were tested in turn, under the same conditions. During the preparation and implementation of testing, it turned out that the hardware capabilities of frequency converters for their use in regulating technological parameters are the same, and the parametric capabilities are different. The frequency converter of the "OWEN" company is equipped with a PI controller, and the frequency converter from "DANFOSS" is equipped with a PID controller. As the results of testing the devices show, despite

Modeling, Control, and Experimental Evaluation of Multifunctional Converter System

The multifunctional converter system (MFCS) is a special topology of three-phase ac motor drives, which inherently integrates a dc-voltage regulation function. First, in order to explain the mechanism of the MFCS, an average model is derived in this article. An equivalent circuit is developed, which explicitly reveals that the MFCS is equivalent to a cascaded dc/dc converter-dc motor drive system. Second, the inverter's mean duty cycle is identified as an independent control degree of freedom for the dc-bus voltage. Then, the influence of pulsewidth modulation (PWM) on the dc-bus voltage is studied. It concludes that space vector PWM is invalid for the MFCS. To address this problem, the zero-sequence voltage injection PWM (ZSVIPWM) is proposed and actually sinusoidal PWM is a special case of the ZSVIPWM. Third, an overall control strategy is proposed for the MFCS, which includes not only the vector control for the motor but also a closed-loop control for the dc-bus voltage. Finally, comparative experiments with the standard topology are carried out on a permanent magnet synchronous machine prototype to verify these theoretical analyses and the control strategy.

Modeling and Simulation for Multiple Damage Progression of Tank-to- Engine Fuel Feed System

Background: A centrifugal vane pump driven by a three-phase AC motor is a key component for modern equipment. Therefore, its condition directly affects the operating and safety performance of the system. Modeling and simulation are effective methods for the system analysis. Methods: A mathematical model of a Tank-to-Engine Fuel Feed System (T-EFFS) is designed based on its phased-mission behavior and structure redundancy. Both of the damage modes that arise frequently in a given type of system are tracked: the fuel feed pump seal damage due to fatigue and the vane damage due to corrosion. Then, a multiple degradation T-EFFS model is established to simulate the fuel pressure at the system outlet under different damage modes. The morphological spectrum decrement index is used to describe the damage of the system. Results: The results show that the T-EFFS model can describe the phased-mission behavior of the system and meet the requirement of the fuel flow rate for the entire mission profile. Then, the decrease in the fuel pressure of the T-EFFS with the cumulative effects of vane damage and crack growth under different behavior modes is simulated along its life span. Conclusion: This work aims to provide a model and data support for a subsequent investigation. The results can be used to fit the health background curve of the system, predict the performance degradation trend of the system at given life points, and further evaluate its remaining service life.

Neutral-Point Voltage-Balancing Strategies of NPC-Inverter Fed Dual Three-Phase AC Motors

In this article, the mechanism of neutral-point potential oscillations of neutral-point-clamped (NPC) three-level inverter fed dual three-phase ac motors is described. In a dual three-phase ac motor drive system, the three-level NPC inverter can be controlled as one six-phase system or two separate conventional three-phase systems. Therefore, this article extends the traditional control strategy, which injects the uniform zero-sequence voltage into the three-phase system to the six-phase system. The relationship of the uniform zero-sequence voltage and the neutral current is analyzed in detail. Meanwhile, the neutral-point potential-balancing strategy adopting dual zero-sequence voltages is presented in this article. The simulation and experiment verify that the proposed strategy adopting dual zero-sequence voltages has better control of the neutral point potential than the strategy adopting uniform zero-sequence voltage.

Performance Analysis of Three Phase Induction Motor based on ATV12HU15M2 Inverter for Control System Practicum Module

<p class="Abstract">Understanding that electrical engineering graduates who have experience and are able to know the electric power system in the industry are the main thoughts of the writer to conduct research. Through the manufacture of a three-phase ac motor control practicum module, which is the type of motor most often used in industrial activities, is expected to provide more knowledge to prospective graduates of electrical engineering engineers. The author determines the two previous research categories chosen as references, namely the training of electric motor modules and the final project of electrical engineering students. In this study the ATV12HU15M2 inverter is used to control changing the frequency value as an input variable to determine its effect on output variables such as voltage, current, power, rpm, and THD. Equipped with SoMove software that is connected to the laptop to be able to change the value of input variables such as motor power, number of poles, and power factors to match the specifications of the electric motor used, the software can also monitor if an error occurs in the system. At the measurement stage, the measuring instrument used is a Power Analyzer to measure the input power of a single-phase system at the source grid PLN, the output power of a three-phase electric motor system, and experimental measurements of motors coupled with a dc generator. For the purposes of data processing, DataView software is used to display the measurement results into a laptop, the resulting display can be in the form of a waveform graph, a graph of THD occurrence, and power information for which the displayed data can be stored. The THD result most optimal at 50Hz frequency with THDv value 18.69% and THDi value 9.04%.</p><p class="Keywords"> </p>

Influence of power traces arrangement on quality and reliability of the DC-link current sensing

This paper deals with quality comparison of current sensing of the two different power traces arrangements and two types of the DC-link shunt resistors. Investigation of current sensing quality was carried out using the two types of high current power stages, which have different power traces arrangement. Both power stages are designed for low-voltage three-phase AC motor drives, mainly in automotive application area. The first power stage contains mixed-signal microcontroller with integrated gate drive unit and analog circuits. The second power stage was designed to accommodate any type of microcontroller connected to the board via connector. The power traces arrangement is analyzed, and the influence on DC-link current sensing is discussed.

Modelling of the wide frequency equivalent circuit of the three-phase AC motor based on vector fitting method

The prediction of conducted interference in the motor drive system is an important part of the automotive electromagnetic compatibility (EMC) analysis. The accuracy of motor electromagnetic interference (EMI) model directly affects the accuracy of conducted interference prediction. For this purpose, based on the measured data, this paper proposes a broadband equivalent circuit model for three-phase AC motors. The motor is regarded as a single-port network, and its common mode and differential mode impedances are measured. Combining the measured data, a rational function expression is established by the vector fitting method. The influence of different fitting orders is analysed under different parameters, and then an equivalent circuit model of the three-phase AC motor is established. The comparison between simulation and experiment shows that the modelling method is simple, accurate, and highly applicable.

Modelling of the wide frequency equivalent circuit of the three-phase AC motor based on vector fitting method

The prediction of conducted interference in the motor drive system is an important part of the automotive electromagnetic compatibility (EMC) analysis. The accuracy of motor electromagnetic interference (EMI) model directly affects the accuracy of conducted interference prediction. For this purpose, based on the measured data, this paper proposes a broadband equivalent circuit model for three-phase AC motors. The motor is regarded as a single-port network, and its common mode and differential mode impedances are measured. Combining the measured data, a rational function expression is established by the vector fitting method. The influence of different fitting orders is analysed under different parameters, and then an equivalent circuit model of the three-phase AC motor is established. The comparison between simulation and experiment shows that the modelling method is simple, accurate, and highly applicable.

Speed Control of Induction Motor on C2000 DSP Platform

Three-phase AC motors are widely used in the industry. Nowadays, it accounts for 90% of the motors used in engine applications in technological lines. Control methods for this object are also quite complete and installed in industrial inverters in commerce. For commercial equipment, operators must not interfere with the control structure due to the closed nature of the system. For small-scale applications and applications that require operators, it is necessary to intervene in the control structure to customize the technology process. However, it cannot be done with commercially available equipment. Therefore, the authors propose a solution to build a standardized hardware system that can interfere with the control structure using the C2000 family microcontroller. The advantage of this solution is that it is inexpensive and allows us to install different algorithms. Besides, it is possible to connect to PC via Matlab/Simulink in real-time control problem.

To Improve A Performance of Induction Motor Using PBO-ANFIS

The performance of intelligent control Adaptive Neuro Fuzzy Inferences system (ANFIS) with Pollination based optimization (PBO) is presented for the speed and torque control of an induction motor using direct torque control in detail. Here a DTC method is being presented and analyzed. This technique consists of a neural network controller, pollination based optimization, a reference model, and an algorithm  for changing the ANFIS weights altogether to limit the speed of the ac machine. A PBO-ANFIS gives better speed control, dynamic behaviour and superior characteristics of the three-phase ac motor with DTC. In this paper, the conventional controller technique is replaced by PBO-ANFIS controller. The proposed technique is compared with the conventional technique and from the comparative study it is seen that the rise time is reduced from 260ms to 1.266ms, settling time is reduced by 725ms to 12.76ms and transient time is reduced by 520ms to 10.99ms times and torque ripples are reduced by 6%. Â

An Analysis of Virtual Flux Direct Power Control of Three-Phase AC-DC Converter

<p>This paper presents an analysis of virtual-flux direct power control (VFDPC) technique for the three-phase pulse width modulation (PWM) ac-dc converter. The proposed VFDPC is developed by assuming the grid voltage and converter line filters quantities are related to a virtual three-phase ac motor. The controller works with less number of sensors by eliminating the voltage sensors used for measuring the three-phase grid voltage. The grid virtual flux which is proportional to the grid voltage will be estimated from the information of converter switching states, line current, and dc-link output voltage. Several analyses are performed in order to study the steady state and dynamic performance of the converter, particularly during the load and DC voltage output reference variations. The proportional integral (PI) controller at the outer voltage control loop of VFDPC is tuned properly and the entire PWM ac-dc converter system is simulated using MATLAB/Simulink to ensure the dc output voltage follow the desired output voltage under steady state and dynamic conditions. Ac-dc converter utilizing the proposed VFDPC is able to generate three-phase input current waveforms that are almost sinusoidal with low harmonics contents which is less than 5% and near unity power factor (<em>pf</em>) operation.</p>

Commutation Analysis of Brushless DC Motor and Reducing Commutation Torque Ripple in the Two-Phase Stationary Frame

The control of brushless dc motors (BLDCMs) is similar to dc motors during the noncommutation interval. However, three phases are involved in electromechanical energy conversion during the commutation interval, making the control of the BLDCM similar to a three-phase ac motor during the commutation interval. A novel commutation analysis method for BLDCMs is proposed based on the coordinate transformation theory, which is used in control of a three-phase ac motor usually. The model of the BLDCM during the commutation interval is acquired in the two-phase stationary frame by using the Clark transformation. The commutation control method for suppressing commutation torque ripple and shortening the commutation time are obtained. Finally, the feasibility and effectiveness of the method is verified by experimental results.

Wavelet-fuzzy speed indirect field oriented controller for three-phase AC motor drive – Investigation and implementation

Three-phase voltage source inverter driven induction motor is used in many medium- and high-power applications. Precision in speed of the motor play vital role, i.e. popular methods of direct/indirect field-oriented control (FOC) are applied. FOC is employed with proportional–integral (P-I) or proportional–integral–derivative (P-I-D) controllers and they are not adaptive, since gains are fixed at all operating conditions. Therefore, it needs a robust speed controlling in precision for induction motor drive application. This research paper articulates a novel speed control for FOC induction motor drive based on wavelet-fuzzy logic interface system. In specific, the P-I-D controller of IFOC which is actually replaced by the wavelet-fuzzy controller. The speed feedback (error) signal is composed of multiple low and high frequency components. Further, these components are decomposed by the discrete wavelet transform and the fuzzy logic controller to generate the scaled gains for the indirect FOC induction motor. Complete model of the proposed ac motor drive is developed with numerical simulation Matlab/Simulink software and tested under different working conditions. For experimental verification, a hardware prototype was implemented and the control algorithm is framed using TMS320F2812 digital signal processor (dsp). Both simulation and hardware results presented in this paper are shown in close agreement and conformity about the suitability for industrial applications.

Design and Experimental Research of Agricultural Low Power Singlephase Frequency Conversion Control System Based on SPWM

In the countryside of China, the main power supply mode is 220V single-phase power, which affects the widely application of three-phase agricultural appliances. What’s more, it means a block to the development of modern agriculture. However, frequency converter technique research is focused on three-phase high power frequency conversion technology at present, and there are very few achievements on the agricultural low power single-phrase frequency conversion research. In this paper, considering the difficulty of widely application of agricultural low power three-phase AC motor because it is not easy to obtain the three-phase power supply, a three-phase AC frequency conversion system under the condition of agricultural 220V single-phase AC power is designed, which can achieve the stepless regulation of the voltage amplitude and guarantee the widely use of the three-phase AC motor under the condition of agricultural 220V singlephase AC power. The experimental results show that the system can output the controlled three-phase AC power when the input is 220V single-phase AC power. And the rational design of the system hardware also provides the technical support for the application of agricultural low power frequency conversion.

Comparison of Output Current Ripple in Single and Dual Three-Phase Inverters for Electric Vehicle Motor Drives

The standard solution for the traction system in battery powered electric vehicles (EVs) is a two-level (2L) inverter feeding a three-phase motor. A simple and effective way to achieve a three-level (3L) inverter in battery-supplied electric vehicles consists of using two standard three-phase 2L inverters with the open-end winding connection of standard three-phase ac motors. The 3L inverter solution can be usefully adopted in EVs since it combines several benefits such as current ripple reduction, increment of phase motor voltage with limited voltage ratings of the two battery banks, improvement in system reliability, etc. The reduction in current ripple amplitude is particularly relevant since it is a source of electromagnetic interference and audio noise from the inverter-motor power connection cables and from the motor itself. By increasing the inverter switching frequency the ripple amplitude is reduced, but the drive efficiency decreases due to the proportionally increased switching losses. In this paper the peak-to-peak ripple amplitude of the dual-2L inverter is evaluated and compared with the corresponding ripple of the single-2L inverter, considering the same voltage and power motor ratings. The ripple analysis is carried out as a function of the modulation index to cover the whole modulation range of the inverter, and the theoretical results are verified with experimental tests carried out by an inverter-motor drive prototype.