Essay On Speed Control

Modelling of the series transformer, VSC and LC filter is presented in this section. A time-varying threephase

As flight systems advances, new power generation is necessary which should be able to provide high-quality power generation, and solution might be Variable Frequency electrical system. The Variable frequency is generated with the power of the perfect sine wave and no harmonic distortion. This type of “Variable Frequency is generated from a generator with a 3-stage brushless with the variable speed and generates the frequency from 360 – 800Hz with an output voltage of 200V.” (Fadil. R.A., Eid. A., & Salam. M. A.,2013)

Many other people continued the development and improvement of electric automobiles and for a time electric automobiles were the preferred type of Automobile because of their quiet ride, quick start-up, and lack of pollution. In fact electric automobiles held the land speed record well into the early 1900’s. However, they began to decline in the early 1900’s because of the increased prevalence and efficiency of the internal combustion engine.

Abstract: This paper investigates the dynamic performance of three phase induction motor by vector control method. The vector control algorithm is calculated on Motorola DSP56F80X. The block diagram is shown in figure which describes the structure of implement vector control algorithm. The result obtained is verified using matlab simulation. Initially speed reference is set at120 radian/s and torque taken as 0 nm. Then motor is run, speed, torque and current wave form is taken. Now speed reference changes to 160 radian/s and torque changes to 200nm and correspondence wave form is shown. I observed that it run smoothly over the full speed range, generate full torque at zero speed, and have high dynamic performance including fast acceleration and deceleration. It was originally developed for high-performance motor application for industrial drives. However, it is becoming increasingly attractive for lower performance applications as well due to FOC 's motor size, cost and power consumption reduction superiority. .. In vector control method machine is control in a synchronously rotating frame where as in sinusoidal machine variables appears as D.C. quantities. In steady state current resolved in to two control inputs I. e. direct axis and quadrature axis component

This project is aim to study the principle of pwm, single-phase inverter, three-phase inverter which leading to design a three-phase inverter(DC-AC) by using the mbed to control switch. This inverter will be intended to drive an induction motor which may need to drive. The work will involve simulation study of PWM generators, induction motors and device selected from.

The complete system will consist of two sections; a power circuit and a control circuit. The power section consists of a power rectifier, filter capacitor, and three phase diode clamped multilevel inverter. The motor is connected to the multilevel inverter. An ac input voltage is fed to a three phase diode bridge rectifier, in order to produce dc output voltage across a capacitor filter. A capacitor filter, removes the ripple contents present in the dc output voltage. The pure dc voltage is applied to the three phase multilevel inverter through capacitor filter. The multilevel inverter has 24 MOSFET switches that are controlled in order to generate an ac output voltage from the dc input voltage. The controlled ac output voltage is fed to the induction motor drive. The motor windings are highly inductive in nature; they hold electric energy in the form of current. This current needs to be dissipated while switches are off. Diodes are connected across the switches give a path for the current to dissipate when the switches are off. These diodes are also called freewheeling

Induction motor phase control is one of the ordinary and uninterested method of electronic AC power control [22]. This method is presented in Fig 2.2 [18, 23]. At the start position of the motor and during the first half cycle operation of the AC sine wave, the switch in the electronic circuit becomes opened

In recent years, conversion of ac line voltages from utilities has been dominated by using a single-phase diode rectifier followed by a single switch boost stage. Designers have embraced the usefulness of this topology since it draws a sinusoidal input current and maintains a unity input power factor under varying load

Index Terms— Double fed induction generator, diode clamped multilevel matrix converters, grid, matrix Converter, space vector pulse width modulation technique, wind turbine.

and high-power applications. For closed loop speed control operation, in current control loop, three phase stator current information is required. The current sensors and the associated accessories increase the complexity of the system, cost and size of the motor drives and decrease the reliability of the system and also more number of power electronics switches means more switching losses and costly. Therefore to overcome this problem a new drive system is proposed which uses four switches and two current sensor, less switches and less current sensors means less switching losses and low cost. In this paper, the PWM technique is therefore proposed to minimize the torque ripple and designed to overcome the disadvantages from other torque ripple

Abstract—This paper proposes direct torque control of induction motor simulation using conventional method and space vector pulse width modulation technique for ripple reduction. Direct Torque Control is a control technique used in AC drive systems to obtain high performance torque control and thereby controlling the speed of induction motor. The principle is based on simultaneous decoupling of stator flux and electromagnetic torque of AC drive system. DTC drives use hysteresis comparators and they suffer from high torque ripple and variable switching frequency problem. The proposed SVM based DTC reduces torque ripples. The basis of the SVM-DTC methodology is the calculation of the required voltage space vector to compensate the flux and torque errors and its generation using the SVM at each sample period. The performance of this method is demonstrated by simulation using MATLAB/Simulink software. Simulation results presented in this paper show the torque, flux linkage and stator current ripple decreases with the proposed SVM-DTC algorithm.

The proposition highlights the DC-connection adjusting control which is the most ordinarily confronted issue in the event of a three-level diode braced inverter, with no extra circuit. Changes of the regulation strategies for the acknowledgment of the DC-connection adjusting control have been proposed. Correlation of the aggregate symphonious bending of the line-to-line voltages at the yields of the two and three-level inverters has been exhibited for PWM, SVPWM &CB-SVPWM methods. The postulation likewise manages the control of the Permanent Magnet Synchronous Motor drive utilizing Field-Oriented Control

The thesis highlights the DC-link balancing control which is the most commonly faced problem in case of a three-level diode clamped inverter, with no additional circuit. Modifications of the modulation techniques for the realization of the DC-link balancing control have been proposed. Comparison of the total harmonic distortion of the line-to-line voltages at the outputs of the two and three-level inverters has been presented for PWM, SVPWM &CB-SVPWM techniques. The thesis also deals with the control of the Permanent Magnet Synchronous Motor drive using Field-Oriented Control technique. A PMSM drive system based on Field

Electrical machines have gained a distinctive interest by experts because their advantages are indisputable because of their ability to adapt to any environment and their efficient efficiency, thus exceeding other non-electric actuators. The induction machine (IM) is currently the most widely used electrical machine in both domestic and industrial applications. Its main advantage lies in its simplicity of mechanical and electrical design (absence of rotor winding (cage machine) and collector, simple structure, robust and easy to build .....). However, these advantages are accompanied by a high degree of physical complexity, linked to the electromagnetic coupling between the magnitudes of the stator and those of the rotor. This is why, for a long time, IM was only used in constant speed drives.(El-kharashi and El-dessouki, 2014).

Using Field Oriented Control, current control is largely unaffected by speed of rotation of the motor[6].In the scheme of filed oriented control motor currents and voltages obtained from the motor are transformed into d-q reference frame. Measured currents from three stator phases these currents which are now in the stator reference frame are converted into two phase using Clarke transformations which are further converted into the corresponding rotor reference frame using Park transformation. The resultant current obtained is dc which is easier for the PI controllers to operate.