Starting and speed control of induction motor pdf files

Therefore in order to control the speed of a standard ac motor, the applied frequency and voltage must be controlled. Motor analysis block diagram induction motor starting can be analyzed using electrical, mechanical, and thermal models which interact as diagrammed in figure 1. Particular aspects before replacing a motor to improve energy e. This paper shows the direct online starter and speed management of 3phase induction motor through vfd. Hence, it initiates a need to control various parameters of induction motor in order to run it properly and efficiently. Torque at a specific speed how intensively the magnetic circuit is used.

Starting of 3 phase induction motors, high starting torque motors, speed control, rheostatic method, pole changing method, cascade control of speed, double cage induction motor, cogging an d crawling of induction motor, induction generator. In speed control by cascading of two induction motors, the rotors of the two motors are mechanically coupled. The alternating current ac induction motor is one of the most rugged and most widely used machines in industry. In the present work, the simulation of speed control of motor at different. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. Pdf speed control of singlephase induction motor using. Pdf speed control of induction motor by using intelligence. The basic idea of an electric motor is to generate two magnetic fields. It is based on freescales 56f800e microcontrollers. The speed of an ac motor depends on the frequency of the input power and the number of poles for which the motor is wound. In addition, electronics can reduce the systems average power consumption and noise generation of the motor.

The operating point is the intersection of the two characteristics and we can fix for a given load and motor parameters. Speed control of three phase induction motor voltage control, voltage frequency. The aim of the paper deals with investigation on the concept of speed control of a threephase induction motor along with energy saving. Motor technologies for higher efficiency in applications. Drm039, single phase ac induction motor control reference. The 3phase set of currents, each of equal magnitude and with a phase. The capacitor motor, which belongs to the singlephase induction motor, is explained in this video. Speed control of induction motor 7 ways to control. M01120 this article explains how to set an akd for driving an asynchronous machine, using an open loop vhz. Up to 150% rated torque can be achieved at reduced speed.

Although it is difficult to control voltage and frequencies at these high powers, the use of a standard induction motor allows a cost effective speed control system to be built. Different method of starting of threephase squirrel cage induction. In this paper, indirect vector method is used to control the speed of induction motor. Modeling of motor starting methods in emtpatp modeling and analysis of motor starting methods the focus on the results presented in this paper will be on motor torque evolution and transients, network voltage, and network current fed to the starter. Therefore the efficiency of three phase induction motor is reduced by this method of speed control. Speed of a dc shunt motor can be varied very easily with good efficiency, but in case of induction motors, speed reduction is accompanied by a corresponding loss of efficiency and poor power factor. The induction motor is made up of the stator, or stationary windings, and the rotor. Dec 23, 2017 speed control with respect to rotor side of the induction motor. The role of cycloconverter in speed control of induction motor is to vary the supply frequency which in turn, changes the speed of motor. A three phase, 12 pole, salient pole alternator is coupled to a diesel engine running at 500 rpm. Single phase induction motor is not a self starting and three phase induction motor is a induction motor speed control is a method of controlling the speed of an im by advantage of using microcontroller based pwm inverter. Simulink model of three phase induction motor file. Introduction to motor starting analysis ced engineering. The rotor has salient poles and a cage so that it starts like an induction motor, and runs like a synchronous motor.

So a new concept of vfd variable frequency drive is used for controlling the speed and limiting the starting current of a induction motor with variable load attached to the motor. Switzerland, 1983 highspeed induction motor drives. Comparison of three types of motor 1 the speed regulation in shunt motor is better than series motor 2 the starting torque of a series motor is more than other motor 3 both shunt and compound motors have definite no load speed, however series motors have dangerously high speed at no load. Direct on line dol starting a standard dol motor draws 600650% of motor full load current. Synchronous speed of the rotating magnetic field of an induction motor is given by, where, f frequency of the supply and p number of stator poles. Internet based speed control and torque analysis of a 3phase. Starting current of induction motor in frequent switching, epe conference 2015. The synchronous speed of an ac motor is the speed of the rotating magnetic field set up by the stator winding synchronous speed rpm 120 x frequency divided by the number of poles. Problems in practice usually arise only when the motor insulation is not suited to the pulsed voltage output of the frequency converter.

The stator is composed of laminations of highgrade sheet steel. Starting torques can be 3 times higher to overcome the starting conditions, causing mechanical stress on the components in the motor. The summation of all torques acting on the motor shaft comprises the mechanical model. Methods of speed control of induction motor electrical. This slip power is utilized for speed control in cascade operation of induction motor. The starting of the motor requires the generation of a rotating magnetic flux similar to the rotating flux in a threephase motor. The speed control of induction motor by considering to control on stator side can also subdivide into several speed controlling.

The problem here analysed concerns the drives providing the use of high speed induction motors. Investigation in induction motor starting and speed control. There are two major components of an ac induction motor. Motors specification of electric motors marshall wolf automation. This paper discusses the performance of a singlephase induction motor drive under nominal load in a closedloop vectorcontrolled system. Development of the induction motor equivalent circuit 258 stationary conditions 258. For autotransformer starting, the current on the motor side will also be presented.

While discussing this topic we will look through the starting, braking and speed control of induction motors. It is because of in induction motor, the performance of induction motor in terms of power factor, efficiency etc. Speed control of dc shunt motor can be easily achieved but in the case of the induction motor, it is difficult to achieve smooth speed control. Generally an induction motor operates at almost constant speed as the load is varied. One motor is called main motor and the second motor is called auxiliary motor. Harley and yao duan georgia institute of technology november, 2009. Motor protection relay schweitzer engineering laboratories. Speed control of induction motor ac motor speed control. Induction motor control is complex due to its nonlinear characteristics. Pdf speed control of induction motors kamakhya basumatary. The singlephase motor stator has a laminated iron core with two windings arranged perpendicularly.

Variable frequency drives vfds popular speed control devices used in industrial, commercial and residential applications. The motor speed can be varied from zero through to typically 120% of its full rated speed. These motors have onl y one stator wind ing, operate with a singlephase power supply, and are also squirrel cage. Highinertia loads increase motor starting time, and heating in the motor. More than 90% of motors used in industries are squirrel cage induction motor due to its rugged and maintenance free design.

My original aim was to bridge the gap between specialist textbooks. Speed control of three phase induction motor electrical4u. Induction motor is practically a constant speed motor as the dc shunt motor. A variable frequency drive vfd also referred to as a variable speed drive is a type of system through which speed of an induction motor can be varied. The torque produced by three phase induction motor is given by, when the rotor is at standstill slip. Speed control of induction motors the speed of an induction motor is given as n 120fp 1s. I bought a 12 thickness planer and it has a 2hp induction motorsingle phase 2hp capacitor start induction motor start problem. So obviously the speed of an induction motor can be controlled by varying any of three factors namely supply frequency f, number of pole p or slip s. The rotor will constantly be turning to align its magnetic field with that of the stator field. Record all nameplate information for the induction motor. Unit 16 electric motors washington state university. Starting current to the induction motor is reduced by applying reduced initial supply voltage.

Induction motor is now called the racehorse of the industry 1. Draw large starting currents, typically 68 x their full load values. Starting current and starting torque is obtained by correct tapping on autotransformer. Single phase induction motor speed control using microcontroller. How intensively the electric circuit is used the type of enclosure type of cooling the duty cycle of the load the frequency of starting and stopping s 34. Speed control of single phase induction motor using ac. It has susceptibility to speed control by regulating rotor resistance. Brush lifting device in a traditional application as the motor achieves nominal speed, the starting resistor is shorted out through the brushes between the slip rings. Frequency inverters also enable stepless speed control. This type of starter is suitable for both star and delta connection motor. Sel701 motor protection relay features and benefits.

Keywords foc, induction motor, pi control, vector control. Control of induction motor drive using artificial neural network. However, by modifying the rotor design the inrush can be reduced to 500% or even 300%. Huge energy savings potential operating centrifugal fans, pumps and compressors vary frequency of electrical supply to an induction motor to vary the motor speed. To study the speed control of induction motor by varying supply frequency. Modern vsds generally offer computing intelligence and are able to be connected to a variety of control systems and. Accurate motor protection with innovative motorstarting analysis provide complete induction motor protection combined with innovative monitoring, reporting, metering, and control capabilities. Anfis based soft starting control of singlephase induction motor using pwm ac chopper control technique. From the equation 1 it is clear that the motor speed can be changed by a change in frequency f, a number of poles p, and slip s. It follows that any eycient method of speed control must be based on varying the synchronous speed of the weld, rather than the slip. In the electrical model, the voltage, v, and the slip, s, determine the rotor current. An843, speed control of 3phase induction motor using pic18 mcus. Operating induction machines in akd, using an openloop voltshz speed control firmware version. His new type of motor, the ac induction motor, is the workhorse of industry to this day.

Speed control of an induction motor there is a various method of speed control of an induction motor. Induction motor speed control using fuzzy logic controller. Supply voltage is controlled for stator input using autotransformers. In general, the induction motor is cheaper and easier to maintain compared to other alternatives.

Induction motor use is limited in many industrial applications requiring variable speed due to high costs incurred in methods of speed control and inefficiency of the methods used. Before discussing the methods to control the speed of three phase induction motor one should know the necessary formulas of speed. Speed control of induction motor 7 ways to control induction. Dec 17, 2019 when the speed control of three phase induction motor is done by adding resistance in rotor circuit, some part of power called, the slip power is lost as i 2 r losses. Introduction this application note describes the design of a 3phase ac induction motor drive with volts per hertz control in closedloop vhz cl. Jun 30, 2015 a three phase induction motor is basically a constant speed motor.

Frequency inverter t1, controlled, stepless motor start with ratedload torque. Explain starting methods of 3 phase induction motor. Induction motor drives starting braking speed control of. By controlling the frequency of stator emf, speed can be controlled. Pdf speed control of induction motor using foc method. Three phase induction motors can start by simply applying power, but single phase motors require an additional starting circuit. Starting of 3 phase induction motors, high starting torque motors, speed control, rheostatic method, pole changing method, cascade control of speed. The main methods employed for speed control of induction motors are as follows. Hence, the synchronous speed changes with change in supply frequency. The rotor speed of an induction motor is given by the equation shown below.

We know that the induction motor is self starting i. Conventional methods for starting and speed control of singlephase induction motor need often quite expensive external electrical equipment. Induction motor drives starting braking speed control of induction motor. The main problem in starting induction motors having large or medium size lies mainly in the requirement of high starting current when directly started. Induction, reversible magnetic brake, contral rated current a applicable reducer singlephase induction 1k motor machine type tooth axis sik40gna 51k40gnc starting output voltage rated torque gcm 2500 2500 cylindrical axis 51k40ac 5rk40aa srk40ac sik40aam sik40acm 5rk40aam 5rk40acm electric capacity of capacity torque gcm. This video describes how a rotating magnetic field is generated in a single phase ac motor. Speed control of a three phase induction motor using. This shortens the life of the brushes and adds extra wear in the motor. The two factors that determine the speed of the weld, are the supply. Single phase induction motor the singlephase motor starting torque is zero because of the pulsating singlephase magnetic flux.

The speed control of induction motor is done at the cost of decrease in efficiency and low electrical power factor. A singlephase induction motor needs a starter configuration to provide the starting torque while a 3phase motor can be inherently selfstarting as the different phases can be manipulated to start the rotor moving. The current level reached during starting will be dependent upon induction motor drive inertia, the difference between motor and driven load torque speed characteristics, engine runup time, and excitation buildup time. The speed control of induction motor is done at the price of reduce in efficiency and low power factor.

Methods of speed control of induction motor electrical concepts. Vector control offers a number of benefits including speed control over a wide range, precise speed regulation, fast dynamic response, and operation above base speed. Starting and control of threephase asynchronous motors eaton. Villata dlpartzmento dz elettroteenica, faeoltii di ingegneria, politeenieo di torino, italy abstract. When the speed stabilizes, the resistorsreactors are eliminated and the motor is connected directly to the mains. Electric motors for explosive atmospheres instructions manual for installation, operation and maintenance of electric motors date.

The first case is a wrim using a rheostat for starting and speed control, the second is an induction motor or wrim with shorted rings driven by a medium voltage variable speed drive, and the third is a wrim with speed controlled by a relatively small low voltage spr drive. An introduction there are various methods for the speed. The impactthatvoltage variations have on ac induction motorperformance austin h. Resistancereactor stator starting the motor starts at reduced voltage because resistorsreactors are inserted in series with the windings. It supplies an induction motor ich has a full load speed of 144wh 0 rpm. Twenty ways to optimize energy efficiency in the use of. Uses soft magnet rotor that is magnetized by the application of current in the stator coils 3. Unit 16 electric motors objectives after studying this unit, the student will be able to state the purpose of an electric motor. Certain topics encountered in the literature on induction motor drives.

Twenty ways to optimize energy efficiency in the use of induction motors electric motors convert electrical energy into mechanical energy. You should also make a dc measurement of stator winding linetoline resistance using a dmm. Actual speed of an induction motor is given as n ns 1 s. The different methods of speed control of induction motor can be broadly classified in to scalar and vector control methods. Pdf an increasing number of applications in high performing electrical drive systems use. Create scripts with code, output, and formatted text in a single. A three phase induction motor is mostly a constant speed motor so its fairly not easy to control its speed. This paper present the speed control of single phase induction motor using arduino with the controlling objectives pwm and spwm. Figure 1a shows an electrical oneline of the low inrush motor starting scheme, and figure 1b shows the speedtorquecurrent profile for dol starting. May 08, 2015 the speed torque curve of a squirrel cage induction motor and the soft starter, 2892016 duration.

Single phase induction motor the singlephase induction machine is the most frequently used motor for refrigerators, washing machines, clocks, drills, compressors, pumps, and so forth. Pdf the induction motor drive is a dynamic nonlinear system with uncertainty in the machine parameters. Communities more files in the power electronics control community. Then it is useful to use some techniques for varying a. The motor is mounted in a test rig that allows one to control the torque applied to the motor shaft and to measure both rpm and torque. Sometimes the data for the motor has been taken from the motor control centre, and this often relates to the kwe electrical. A motordriven system consists of several components. Power factor control and direct torque control can help to boost the performance of a threephase induction motor drive.

Disadvantages of 3 phase induction motor induction motor has low inherent starting torque draw large starting currents, typically 68 x their full load values speeds not easily controlled as dc motors operate with a poor lagging power factor when lightly loaded induction motor components an induction motor has two main parts. The resistance is controlled using a triac model type 12 switch and a control logic. Speed control of induction motor detailed explanation. Variations in the voltage will l1ave a significant impact on the motor starting torque. However, induction motors do not inherently have the capability of variable speed of operation. The speed of a threephase induction motor driving a given load is determined by matching the torque speed characteristics of the motor and load, as shown in fig. The vector control algorithm is based on two fundamental ideas. Zhou 5 proposed an fpgarealisation of a speed servo controller of.

Starting of 3 phase induction motors, high starting torque motors, speed. Pdf control of induction motor drive using artificial. Traditional design of cage rotor induction motors ronald g. Jan 05, 2016 speed control we have seen that to operate eyciently an induction motor must run with a small slip. Out of all the electrical machines, induction motor is the most used machine in industries. How do we control the speed of a single phase induction motor. Induction motors are widely used electrical motors due to their reliability, low cost and robustness. As the name suggests the synchronous motorsrotates at synchronous speed. An induction motor is practically a constant speed motor, that means, for the entire loading range, change in speed of the motor is quite small. Pdf this paper gives the comparative study among various techniques used to control. The impactthatvoltage variations have on ac induction. Induction motor speed control is done by varying the frequency of the applied voltage.

Moreover, they require mechanical switches, which are the most troublesome parts. An introduction there are various methods for the speed control of an induction motor. The first is the flux and torque producing currents. Speed control of induction motor using pi and pid controller. The control strategy to be applied is known as indirect field oriented control. It is widely used in industry due to low cost and rugged construction.