Elimination of tonal acoustic noise in choppercontrolled dc. Chopper fed dc drives separately excited dcm current. Chopper drives are also used in batteryoperated vehicle where energy saving is of prime importance. Project on speed control of dc motor using chopper circuit duration. Pdf armature voltage speed control of a separately excited. Feb 10, 20 chopper fed dc drives a dc chopper is connected between a fixedvoltage dc source and dc motor to vary the armature voltage. The dc motor speed controlled by 1 armature voltage control below base speed 2 flux control above base speed. Study of speed control of dc series motor using dc chopper.
Simplified crosssection schematic a and equivalent scheme of separatelyexcited dc motor. Comparison of speed controlled dc drives with and without subordinate current loop design of an optimal, autoadaptative current loop for d. Motor drives torquespeed and control arrangements developments in industrial d. Dc motor chopper control 1 creation of a dc permanent magnet motor simpower block in library. Here,the power semiconductor switches are scr thyristor,mosfet,igbt,this type of speed control is called wardleona rd drive. A substantial number of different ac dc and dc dc topologies appropriate for dc motor drives are presented. Industrial drives and applications vtu notes pdf ida pdf.
Speed control of dc motor using chopper electric motor. A chopper is a device that converts fixed dc input to a variable dc output voltage directly. Chopper controlled dc drives free download as powerpoint presentation. In electronics, a chopper circuit is used to refer to numerous types of electronic switching devices and circuits used in power control and signal applications. Aug 11, 2017 there are two primary types of drivers for stepper motors, constant voltage drives also referred to as lr drives, and constant current drives also referred to as chopper drives. Chopper controlled dc drives single and multiquadrant converters, motoring and braking operations. The power circuit of the drive consists of a non controlled rectifier, a filter, a braking chopper, and a 4quadrant pulse width converter. Chopper circuit is simple and can be modified to provide regeneration and the control is also simple. It has two operating modes to represent a detailed or an averagevalue chopper. Figure below shows the basic arrangement of a dc chopper feeding power to a dc series motor. The variable voltage to the armature of a dc motor for speed control can be obtained from a dc chopper which is a single stage dc to dc conversion device. This paper presents the speed control of a separately excited dc motor sedm using a speed controller designed to vary the armature voltage. Rectifier control of dc series motor, chopper controlled dc drives, chopper chopper control of separately excited dc motor. Step up down chopper chopper controlled dc motor control strategies of choppers.
In many different applications it is required to control speed of dc motor. Hence the fopid controller is a sum of fractional operators along with controller gains. The voltage variation at the load terminals can be obtained by using either current limit control or time ratio control. What are the advantage and disadvantages of dc drives the. Dc motor speed control using chopper engineers garage. The motor drive shown is a speed controlled system. The dc motor speed can be controlled through power semiconducto r switches. Pdf armature voltage speed control of a separately. Rectifier control of dc series motor, chopper controlled dc drives, chopper control of the separately excited dc motor. Regenerative braking performance analysis of a thyristor chopper controlled dc series motor december 1981 ieee transactions on industrial electronics and control instrumentation 284. In addition, due to the use of high switching frequency dc dc converters, a lower armature current ripple compared with thyristorbased dc drives is.
One difficulty with stepper motor operation is that the time constant lr of the motor windings prevents current from increasing rapidly during pulses. Dc drives are less complex as compared to ac drives system. Chopper control of separately excited dc motor the chopper converts the fixed dc voltage to variable dc voltage. The proposed control technique may be used for the speed control of solar power fed dc motor drives which can be used in rural small scale industry application.
It simply chops fixed dc and generates variable dc. Let us first understand how it generates variable dc. Chopper fed current controlled dc motor drive using pid. Industrial drives and applications electricalnotesengine. Implement dc chopper model for dc motor drives simulink. Jun 08, 2019 chopper is a basically static power electronics device which converts fixed dc voltagepower to variable dc voltage or power. The experimental work which forms the basis of the paper involves driving a dc elimination of tonal acoustic noise in dc drives 109 motor from a pwm chopper, the switching frequency of which was controlled using a random dither strategy. This paper presents modelling and numerical simulation as well as prototype for speed control of dc series motor using a dc chopper. The speed control loop outputs the reference armature current of the machine. This drive features closedloop speed control with fourquadrant operation. Krishnan electronic control of machines develops a systematic approach to motor drives. Chopper controlled dc drives courtesy nirav mehta sir.
The pulsewidth modulation method of control of semiconductor devices can help in controlling the output voltage of dc drives in turn controlling the speed for a wide range. Single phase dc drives, three phase dc drives, chopper drives. Chopper can increase or decrease the dc voltage level at its. Regenerative braking performance analysis of a thyristorchopper controlled dc series motor december 1981 ieee transactions on industrial electronics.
The fourquadrant chopper dc drive dc7 block represents a fourquadrant, dcsupplied, chopper or dcdc pwm converter drive for dc motors. There are two primary types of drivers for stepper motors, constant voltage drives also referred to as lr drives, and constant current drives also referred to as chopper drives. Chopper is a device that gives variable dc output from applied fixed dc input. It is nothing but a high speed switch which connects and disconnects the load from source at a high rate to get variable or chopped voltage at the output. International journal on recent technologies in mechanical. Chopper control of separately excited dc motor circuit globe. This book places emphasis on practice through the use of extensive modeling, simulation and analysis to help readers better understand the subject. A chopper is a high speed onoff semiconductor switch which connects source to load and disconnects the load from source at a fast speed.
With dc supplies a chopper was used and with an ac supply a controlled rectifier was used. Chopper controlled dc drives electronics electronic. Essentially, a chopper is an electronic switch that is used to interrupt one signal under the control of another. Development of high performance motor drives are very essential for industrial applications. In drives with lower power, igbt transistor switches are used. Gto thyristor switches used in drives with large power are shown in the figure. Elimination of tonal acoustic noise in choppercontrolled. What are the two basic methods of speed control of dc motors. Converter half controlled converter,full controlled converter, dual converters. For all the chopper configurations operating from a fixed dc input voltage, the average value of the output voltage is controlled by periodic opening and closing of the switches used in the chopper circuit. In addition to armature voltage control, a dc chopper.
What are the types of control strategies in dc chopper. Design and implementation of pid controller for a two. Up to about 1990 the dc series motor was used in many countries for traction train, tram, metro. Here you can download the industrial drives and applications vtu notes pdf ida pdf vtu of as per vtu syllabus. Electric traction electric drives jeanmarc allenbach 4. Principle of operation of the chopper four quadrant chopper circuit chopper for inversion chopper with other power devices model of the chopper input to the chopper steady state analysis of chopper controlled dc motor drives. Chopper fed current controlled dc motor drive using pid controller. Speed control of dc motor using chopper free download as powerpoint presentation. Dc choppers applications in dc motor drives and renewable. The speed control strategies of dc motor plays an important role in the drive performance. Realization with an hybrid device including a microprocessor control of dcdrives by microprocessors simulation of the chopper controlled dc series motor. A high performance motor drive system must have good dynamic speed command. A separately excited dc motor fed from a dc chopper employing trc strategy is shown in fig. Dc choppers chopper drives are widely used in traction applications all over the world.
The separatelyexcited dc motors are mostly used in controlled drives, owing to the possibility of independent field and armature current control and related superior control features in a wide speed range. Mehta power electronics engineering department, vishwakarma government engineering college, chandkheda 382424. The variable dc voltage is controlled by varying the on and offtimes of a converter. Chopper drive for stepper motor linear motion tips. Dc drives are normally less expensive for low horsepower ratings. Schematic of an inverter using a vibrator as a chopper. Chopper controlled dc motor drives, modeling of polyphase induction machines, phase controlled motor drives, frequency controlled induction motor drives, vector controlled induction motor drives, permanent magnet synchronous and brushless dc motor drive modeling and control. The fourquadrant chopper is widely used in reversible dc motor drives. The variation of time ratio at constant chopper frequency provides a variable voltage. The speed of the motor is controlled from 0 to the. Control in power electronics and electrical drives 1st. The chopper is supplied from a constant dc voltage using batteries. The speed control of dc motor for different applications is very important.
Dc motor ieee paper 2018 analysis and simulation of adaptive power system with dc motor type dynamic loads free download abstract in this paper proposes an adaptive power system aps, it is used to mitigate the negative impacts levied on the platforms resulting from large dynamic loads. A dc chopper is used to convert the fixed dc voltage to variable dc voltage and it is connected between a fixed voltage dc source and a dc motor to vary the armature voltage. Of course, variable frequency drives vfds and ac motors are now offering an alternative to dc drives and motors, but there are many other applications where dc drives are extensively used including crane and hoists, elevators, spindle drives, winders, paper production machines, crushers, etc. The principal scheme of a dc drive is given in fig. The fourquadrant chopper dc drive dc7 block represents a fourquadrant, dc supplied, chopper or dc dc pwm converter drive for dc motors. Chopper is a basically static power electronics device which converts fixed dc voltagepower to variable dc voltage or power. Question bank with answer mahalakshmi engineering college. The chopper block models a standard halfbridge one leg, two igbts or fullbridge two legs, four igbts converter model.
Here applying pulse width modulation pwm signals to the converter with respect to the motor input voltage it is one of the methods most employed to drive a dc motor. Current drawn by the chopper is smaller than in phase controlled converters. Pdf regenerative braking performance analysis of a. A substantial number of different acdc and dcdc topologies appropriate for dc motor drives are presented. Chopper fed speed control of dc motor using pi controller. Solid state speed control of dc motor the dc motor speed can be controlled through power semiconducto r switches. The converter output is applied to the armature controlled dc motor. This technique of randomly changing the switching frequency is an example of a dither stratagem. One of the popular methods of speed control of dc motor is using chopper. References a s awad, e a mohamed, m m eiegm, and a i said 1997, speed control of dc motor drives based on efficient utilization. Dc drives, because of their simplicity, ease of application, reliability and favorable cost have long been a backbone of industrial applications. The use of speed controller is to take an signal sample of speed and to bring the motor to that desired speed.
Dc chopper device has the advantages of high efficiency, flexibility in control, light weight, small size, quick response and regeneration down to very low speed. Apr 24, 2015 step up down chopper chopper controlled dc motor control strategies of choppers. This paper mainly deals with controlling dc motor speed using chopper as power converter and pi as speed and current controller 10. Selfcommutated devices directly on or off devices via gate like mosfet, igbt, power transistors, gto and igct are used for making choppers because they can be commutated by low power control signal and do not need commutation circuit. The main advantage of this drive, compared with other dc drives, is that it can operate in all four quadrants forward motoring, reverse regeneration, reverse motoring, and forward regeneration. The load current can be determined using the relevant equations. By applying chopper it is possible to implement regeneration and dynamic braking for dc motors experimental details. What are the different types of single phase dc drives. Torque speed characteristics of converterfed dc drives week 3.