Vector Control of Multimotor Drive and Introduction to Single Multiphase Motor

Three-phase induction machines are today a standard\nfor industrial electrical drives. Cost, reliability, robustness and maintenance free operation are among the reasons these machines are\nreplacing dc drive systems. The development of power electronics\nand signal processing systems has eliminated one of the greatest\ndisadvantages of such ac systems, which is the issue of control. With\nmodern techniques of field oriented vector control, the task of\nvariable speed control of induction machines is no longer a\ndisadvantage. The need to increase system performance, particularly\nwhen facing limits on the power ratings of power supplies and\nsemiconductors, motivates the use of phase number other than three,\nIn this paper a novel scheme of connecting two, three phase\ninduction motors in parallel fed by two inverters; viz. VSI and CSI\nand their vector control is presented.

The advancement in power electronics made it possible to have high performance and high reliable motor drive. Induction motor is preferred over other motors due to its robust construction and high performance characteristics. In the hardware setup of induction motor drive, MOSFET based inverter has been implemented. Sinusoidal Pulse Width Modulation (SPWM) has been implemented for the control of the switching angle. The SPWM inverters provide an improved methodology to control amplitude, frequency and harmonics contents of output voltage source inverter (VSI). The switching signal is generated with the help of d-space and microcontroller. In this paper, three phase inverter using SPWM with 180° conduction mode has been designed and implemented. The output waveforms of 1 hp, three phase induction motor under various load conditions is presented and discussed.

In switched reluctance motor drives, the combination of power-electronic converter and a motor phase defines a resonant circuit, comprised by the motor phase inductance and the parasitic capacitance of converter switches, power cables and motor phase winding. If a motor phase is excited by applying very short voltage pulses, the resonance frequency of the circuit can be observed through the subsequent damped oscillation of the induced voltage in the phase. As the phase inductance and associated resonance frequency depend on the rotor position, the method provides a means for estimating the rotor position. This paper discusses the influence of the magnetic inductive coupling between motor phases on the observed damped voltage resonance. It is shown that the motor-converter combination can be modelled as a system comprising different resonant circuits, each associated with one phase of the machine, which are mutually coupled due to the inductive coupling between the motor phases. An eigenvalue analysis reveals the different eigenfrequencies and modes of oscillation for this system. It follows from the analysis that damped voltage resonances occur in all phases of the machine due to the mutual coupling. The model is used to determine the influence of voltage pulses, applied to a single phase or simultaneously applied to different phases, on the observed damped voltage oscillations, and thus on the rotor position estimation.

Along with the development of the industrial sector, companies are competing to create quality and affordable products. To support production, automation tools have emerged that help the production process so that it is faster. One of the machines that is widely used by large factories is a 3-phase induction motor. 3-phase induction motors are often used in driving equipment in industry because they have a simple construction, are relatively cheap, lightweight, have high efficiency, and are easy to maintain. This study utilizes the A3114 hall effect sensor device, PZEM-PP4T Sensor, 20x4 LCD, ESP32 module, Relay, Mitsubishi D700, MCP 4725 Sensor. The tests carried out showed that the performance of the sensor for measuring speed, voltage, and current on 3-phase motors has a high level of accuracy. Testing of motor speed shows a difference in speed value (Rpm) between the hall effect sensor and the tachometer, with an average accuracy percentage of 4,12%, indicating that the hall effect sensor has a fairly good level of accuracy. For voltage measurement, the Pzem sensor compared to the Multitester produces an average accuracy percentage of 0,90%, indicating that the pzem sensor is very reliable. Meanwhile, current testing shows a difference in value between the pzem sensor and the multitester with an average accuracy percentage of 0,98%, indicating a fairly high level of accuracy. Overall, this system can be relied on for measuring operational parameters of 3-phase motors because it has consistent and good accuracy. With this research, the 3-phase induction motor monitoring system which was originally done manually has changed to automatic and has a fairly high level of work efficiency.

This study investigates the effect of phase transposition on the performance of the five-phase induction machine with different stator connections, namely, star, pentagon, and pentacle. The possibility of phase transposition for the five-phase machine can be calculated from the permutations of the number of phases, which yields 120 possible sequences that the five-phase machine can be connected. The sequences in the three-phase induction machine provides either a forward- or a backward-rated full speed. However, among these 120 connections for the five-phase induction machine, this study investigates which sequences will provide forward speed, reverse speed, balanced operation, and unbalanced operation. This study also discusses the effect of these sequences on machine performance.

In this paper, an approach for reducing the torque ripple in a two phase unsymmetrical induction motor is analyzed. A single phase induction motor is basically a two phase induction motor and generally, the windings on the stator are not identical. Hence, it is called unsymmetrical two phase induction motor. If an unsymmetrical motor is supplied by two phase balanced supply voltages then the ripples in the electromagnetic torque are unavoidable. However, if the supply voltages are made unbalance to counter the unbalance in the windings the torque ripple can be reduced. The mathematical model of the machine in stator attached reference frame is used to derive the torque expression in terms of stator currents. The torque expression consists of a constant term and a pulsating term. These terms used together unable finding the conditions on stator currents and hence stator voltages so that the ripples in the torque produced can be mitigated.

Modeling of three phase induction motor has been extensively discussed in literature. Several models have been developed and applied by different authors to solve different problems. This paper presents a differentmodel of the symmetrical three phase induction motor in which there is an alignment of the direct axis component of the rotor flux vector to direct axis of the reference frame. The alignment reduces the quadrature axis flux component to zero, removes the dependencies associated with the d-q components of the stator current and simplifies the rotor dynamics. The model is not commonly used in literature to study motor behavior when vector control is not the objective. The model is analyzed in the synchronous reference frame and simulated. Simulation results for torque, speed and flux in the motor are presented. Also presented are the waveforms of stator voltages and currents in both the d – q and a-b-c reference frames and the rotor d-q axis currents. These results provide a correct description of the three phase induction motor behavior under load and no-load conditions.

An electric drive system consisting of two three — phase induction motors independently controlled by an integrated dual inverter is modeled and simulated in Matlab/Simulink. The introduced topology can be used in an electrical vehicle where the main machine is used as a traction drive and the auxiliary machine can be used for air conditioning purposes. While the traction motor is driven by three legs of the used inverter, the auxiliary motor requires only two legs in the introduced topology. This is achieved by connecting a phase of the auxiliary motor to the neutral point of the traction motor. Closed loop control is carried out under different conditions including trapezoidal speed profile tracking and steady — state performance with load variation.

Steam Generator of Electricity Power Plant at PT. PLN (Persero) UPDK Keramasan of ULPL Indralaya, South Sumatra Area. This power plant has 3-phase induction motors, which are the most commonly used motors because of their reliability. The 3-phase motor is directly connected to the supply at a high starting current of around 5 to 7 times the motor rating current (nominal current). This large starting current can cause a considerable voltage drop on the supply line, thus affecting other loads connected to the supply line. Because the large current flows for a long time, it causes the motor to heat up, which will damage the insulation. Therefore, when starting the motor, the motor bus voltage must be kept at around 80% of the voltage rating. This study investigates whether the motor could start successfully under the operating conditions. We used ETAP software to simulate motor starting and also analyze these motors is to obtain the values of starting current, starting torque, and voltage drop from the results of using VFD (variable frequency drive) on two motor units in LV Switchgear SUS-1 whose previous existing conditions were using DOL (direct on line). A result of our studies, we found that the system can still maintain a bus voltage of 99.94%, a small starting current when starting the motor of 0% FLA (1 second), and reaches 99% FLA (4 seconds) with a starting torque of 54% & 57% of the load torque.

In general, rotating electrical machines can be modeled by an equivalent two phase machine. This means that an unbalanced 3-phase induction motor can be modeled by using an unbalanced two phase induction motor model. This paper shows this concept by modeling a faulty 3-phase induction motor in which one of its feeding phases is opened. The paper also presents a new fault-tolerant vector control (which is modified from the conventional vector control) that can be used to control a faulty three-phase induction motor. Simulation results show the good performance of the proposed method.

The major disadvantage of pulse width modulation generating by microcontroller is that the process completed in a longer period and slower system response then FPGA based system, while if based on DSP is its insufficiency in the case of flexibility and reliability. Speed demand will operate for and performance the reliable controller pushes for the implementation of evocation of PWM signal at FPGA. This research aim to design and to implement a device with uniform pulse width modulation based on FPGA Altera ACEX1K as drive inverter to control the rotational speed of a three phase induction motor. Design stage of implementing a UPWM signal generating system started from design entry, compiling, simulation and verification, and hardware configuration at FPGA Altera acex1k50tc144-3 development system with MAX+Plus II 10.2 Baseline software. At this research, three phase inverter circuit designed using MOSFET SK727 with DC input voltage 310 V. Inverter output then loaded with a three phase induction motor Y2 712-4, 370W/380V, 50Hz model. Result of this research indicate that the generating of UPWM signal design can be implemented in the form of hardwared logic at FPGA Altera acex1k50tc144-3 development system, and applicable to drive inverter as rotational speed controller of a three phase induction motor. Speed regulating function of this system was implemented by modulation index and frequency setting. At this research, system have been tested at setting frequency 10-50 Hz with the variation of modulation index, and yield a range of range 458-1468 rpm using Three phase Motor mentioned above.

Generally three phase motors are better than single phase motors but three phase system cannot be used in many applications for house. Especially single phase motors are used in city centers because of structure of the single phase feeder system. In general, small powered single phase motors in the range of 0.18–1.5 kW are used in small workplaces, portable hand looms, homes, fans, kitchen equipment, vacuum cleaner, drills and etc. In this paper, characteristic performance features of the single phase electrical machines that named universal motors, single phase induction motors (IM), shaded pole motors and 24 V permanent magnet direct current (PMDC) motors are studied. These motors are grouped in special electrical machines. Operational principles of the motors, areas of the usages and performance characteristics are given comparatively. Tests are conducted for motors. Current, voltage, revolution per minute, powers are given in graphs. ANSYS Maxwell programme is used for computer aided design of transient motor performances. Electrical characteristics of the motors are simulated with programme. Dynamical transient analysis of the motors are conducted respectively. It should not be forgotten that the data, graphs and tables obtained will help the students to learn the motors better in the Special Electrical Machines Course and Laboratory.

The extensive use of power electronics devices in power systems, including rectifiers and inverters, presents considerable issues regarding power quality. One problem is the creation of current and voltage harmonics, which result in load waveform distortion, voltage fluctuation, voltage drop, and equipment overheating. Harmonic current sources are prevalent in commercial, institutional, and medical establishments, encompassing computer power supplies, fluorescent lights with electronic ballasts, elevator motors, and electrical devices using switch-mode power supplies. Active power filters (APF) represent the most effective method for harmonic reduction and may be used across many applications. This study employs a digital active power filter to eliminate harmonics from the source current in a grid system characterized by non-linear demand. Nonlinear loads are essential components of every power system. The advent of power electronics has resulted in switching components constituting a substantial portion of electrical demand. These features create discontinuities in lines, exacerbating line losses and diminishing power quality and sine wave integrity. Passive filters effectively eliminate harmonics at specified frequencies within the design. Active filters, conversely, operate in accordance with the prevailing harmonics. This work develops a shunt active power filter that mitigates current harmonics generated by non-linear loads. The active filter includes a voltage source converter (VSC) that functions in conjunction with a DC coupling capacitor. The VCS delivers power at the point of common coupling (PCC). The reference current is obtained by the instantaneous power theory. The instantaneous power theory, or PQ theory, has been enhanced with the FIS control system to optimize DC voltage generation over the DC link capacitor. The fuzzy system substituting the PI controller has a 49-rule base structure organized in a 7x7 configuration for the generation of error signals. A comparative study of DC voltage and total harmonic distortions (THDs) is conducted using MATLAB software and the FFT analysis tool..

This study proposes the method of real-time simulation for the field-oriented control (FOC) of an asynchronous - phase induction motor (IM) based on the parallel proportional-integral (PPI) technique, to control the motor speed. The proposed control strategy requires two independent direct controllers for flux and current through the 3 level-cascade inverters with the algorithm of carrier phase modulation (PM). In particular, the stator field-oriented vector control (SFOC) will be chosen rather than the rotor field-oriented vector control (RFOC) caused by the requirement of voltage, current and stator resistance parameters. The result of real-time simulation is provided by applying Sim-Power-Systems of Matlab-Simulink software via RT-LAB compiler and the hardware simulation in hardware in loop (HIL) via OPAL-RT for 1-Hp, 1400 rad/s IM motor. These simulation and experimental results show the robustness of the PPI controller in the presence of parameter variation, such as, the Rs and Rr resistances increasing by 2 times, changing of torque and speed with the appearance of disturbances.

The research purpose is to control a six phase induction machine by the combination of the concepts of predictive control and extended kalman filter at various operating conditions. Speed sensors do not have good performance at very low speed and this will cause the system to malfunction. For this reason, an extended kalman filter is used to estimate the speed of six phase induction motor. In this paper, a dual three phase induction motor is modeled and a simple predictive control is used to control the speed of the motor. Simulations have been performed for various conditions of loads and speeds and their results depict correctness and robustness operation of the whole system.