The primary goal of the work is to make a cheap and reliable protection system for three phase induction motor system. Induction motor drives with closedloop control are used in similar applications to d. Medium induction motor winding insulation protection. 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. This system protects the 3phase ac motor from single phasing and overheating. Jul 17, 2016 phanibabu july 17, 2016 july 5, 2019 no comments on single phasing of three phase induction motor electrical motor is an important component of an industry. The overall block diagram of the motor protection system is shown in fig. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. In the case motor stalls or is unable to start due to huge load, it will take a current from the supply which is same as the locked rotor current.
This paper is to monitor the operating conditions of singlephase induction motors. S bharadwaj reddy april 24, 2016 september 11, 2016. Threephase induction motor protection systems and its. It is logical that the least expensive, lowest maintenance type. For protection of motor, we have to identify the various causes of failure and to address the same. Recommendations are given in regard to the selection of both overcurrent and earth leakage protection of induction motors that consider not only the motor protection requirements, but also the limitations on the protection devices that may result from the abnormal. Pdf protection method against induction motor single. It is based on freescales 56f800e microcontrollers, which are ideal for motor control applications.
The micro controller based motor protection system combines control, monitoring and protection function of induction motor from incipient faults in one assembly. Electrical, mechanical, and thermal motor characteristics define the frame needed for effective motor protection running stage, starting stage, and lockedrotor conditions serve to determine the main motor parameters motor heating and thermal damage motor characteristics depend on both positiveand negativesequence current in the. Details description of all types of fault is discuss below. Well it may also lead to fail permanently due to dry run of the motor. Induction motor protection system the circuit diagram of the threephase induction motors is shown in the figure below. Motor protection against single phasing and overheating. If any of the phases, out of the 3phases is misplaced and also if the motors temperature during process surpasses the set value, the supply to the induction motor is cutoff instantly. Figure 1 proposed protection scheme of 3o induction motor. An induction motor can be defined as the ac electric motor device in which a power source fed by the alternating current with the help of a primary winding. Motor faults motor protection overview ge grid solutions. Motor protection relay for high voltage induction motor. That is why sel offers an industryleading product with the most extensive warranty.
Induction motor protection system based on fuzzy logic authors. Aug 31, 2018 the basic function of a protective relay is to identify the fault and isolate faulty part from the healthy part of the system. Recommendations are given in regard to the selection of both overcurrent and earth leakage. Induction motor fault detection, protection and speed control using arduino abstract. A protection scheme for threephase induction motor from. Online condition monitoring of the induction motor has been widely used in the detection of fault.
Medium induction motor winding insulation protection system. Protection of 3 phase induction motor using microcontroller ijareeie. You should also make a dc measurement of stator winding linetoline resistance using a dmm. Providing a protection system is very important in industries, using lot of motors such that production is not hampered owing to failure of any motor. Protection of induction motor relay fuse electrical. To make induction faults, sensing circuits have been designed. Record all nameplate information for the induction motor. For higher hp 250hp motors we prefer high voltage, because it will reduce operating current and the size of the motor why we require protection of motors. Protection relay setting for start time greater than stall time a successful start b unsuccessful start. Hence, for three phase induction motors, it is necessary that all the three phases of supply be present and the motor temperature be within the permissible limits. Voltage and current measuring circuit blocks stand for relative measuring circuits. The faults in the induction motor may lead to breakdown of the induction motor and an increase in expense to the industry.
The paper presents a reliability assessment of a widely used protection system of large power squirrel cage induction motors. This approach is robust, but measurements need be made for each motor. Here in this system a direct 3phase 50hz ac supply is at first transferred through zennon diode stabilized voltage drop setup to an or nand gate integrated logic circuit in order to recognize proper ryb sequence arrangement by fixed duration pulse series. An induction motor can therefore be made without electrical connections to the rotor. The induction motor experiences various kinds of electrical faults such as overvoltage or under voltage, unbalanced voltage, overload, earth fault, phase reversing.
A system is designed and implemented to make protection for faults due to single phasing, voltage unbalance and under voltage in a 3ph induction motor. Protect asynchronous induction and synchronous motors with one sel7105 motor protection relay. Although an induction motor is highly symmetrical, it may still have a detectable sig. The induction motor block implements a threephase induction motor. Induction motor protection system linkedin slideshare. Sel7105 motor protection relay schweitzer engineering. To understand this we need to know the cost associated with the failure of motor, i. Induction motor protection system sures kumar so ganesan tk2785 s97 2007. Feb 02, 2019 protection of induction machine electrical paathshala. Magnetic contactor starter essentially consists of a set of start and stop push buttons with associated contacts, overload and underload protective devices. Introduction three phase motors can be classified into two types. Earth fault identification in a three phase system duration. The thermal parameters are calculated from the motor dimensions and offline experiments.
These sensing circuit sense the faults occur in an induction motor. It contains a full range of selectively enabled, self contained protection and control elements as detailed in the functional block diagram. Protection of induction machine electrical paathshala. The stator of the three phase induction motor consists of three main parts i. Pdf the goal of this paper is to protect induction motors against. Induction motor protection system block diagram and its working. The main purpose of our project is to protect an induction motors from faults such as single phasing, overvoltage, over temperature and under voltage.
Induction motor protection system block diagram and its. Sel understands how critical it is to provide continuous reliable motor protection. Stator frame it is the outer most part of the three phase induction motor. The system is designed as a motor control system for driving mediumpower, 3phase ac induction motors.
These drives are also particularly suited to applications that must operate at very high speeds with a high level of field weakening, for example spindle motors. These factors make mathematical modelling of motor control systems difficult. Pdf 3phase motor soft starter with gsm modem communication. Pdf protection of induction motor using plc researchgate. Parameterbased approaches estimate the temperature from the variation of the resistance of the stator and rotor. All the three phases are rectified, filtered and regulated and given to operational amplifier where. The principle motivation behind our project is to protect an induction motors from faults, for example, single phasing, overvoltage, over temperature and under. The basic idea of this project is to give safety to the induction motor. There are crucial differences between the protection of induction motors and.
Induction motor seminar ppt, pdf report study mafia. Using these parameters we can easily detect faults such as overvoltage, overcurrent, overload, excessive heating, crawling and undervoltage. The induction motor can be isolated from the supply in case of any of the faults with relays. Induction motor fault detection, protection and speed control. Induction motors protection and starting by viv cohen. They are also critical components in many commercially available equipments and industrial processes. This three phase induction motor protection system using pic microcontroller, protects the three phase induction motor during any fault condition such a current or voltage variation, in any phase of three phase ac supply as well as it also provides the protection during vibration, speed and temperature fault. In the system, three potential transformers with transformation ratio 4005v are connected to each phase of induction motor. An induction motor or asynchronous motor is an ac electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding.
Apr 09, 2015 this ppt exlains how protect an induction motor from single phasing and over temperature. Induction motor protection interview questions answers what are the type of faults that are likely to occur in operation of 3 phase induction motor. Protection of three phase induction motor from under voltage, single phasing, over current and phase reversal provide the smooth running of motor improves its lifetime and efficiency. Abstract this paper include a protection scheme for three phase induction motors against singlephasing faults. There is a wide range of ac motors since they can be used in numerous applications. The stator core is built of sheetsteel laminations that are supported in a frame. Three phase induction motor protection system ijraset. The experimental results have shown that the induction motor was protected against the possible problems. Protection of induction motors is important because most industrial applications use induction motors from the market due to their high robustness, reliability, low cost and maintenance and high e.
This ppt exlains how protect an induction motor from single phasing and over temperature. The implemented protection system can be programmed to suit a wide range of induction motor sizes, and to monitor the motor parameters during its operation and after a fault occurrence through. These motors work on 3phase supply and a standard temperature to keep the loads at preferred conditions. The start push button is a momentary contact switch that is held normally open by a spring. Above 90% of motors used in an industry are induction motors, because they are cheap, robust and easy to maintain. By default, the block sets the simulation type parameter to continuous to use a continuous sample time during simulation. The main concept of the project is to develop an induction motor protection system for protecting the motors from any damages occurring from single phasing. Medium voltage induction motor protection and diagnostics. In an induction motor, the electric current in the rotor needed to produce torque is obtained via electromagnetic induction from the rotating magnetic field of the stator winding. Its main function is to support the stator core and the field winding. Introduction induction motor is the backbone for every industry.
Hence, for the protection of the motors from mechanical damage and to increase its life time, it is very necessary to protect the phase motors from single phasing and overheating. Features include broken rotor bar detection and variablefrequency drive vfd support as well as options for arcflash detection afd, differential protection, and synchronous motor protection. Free download induction motor seminar ppt, pdf report. An induction motor also known as an asynchronous motor is a commonly used ac electric motor. It is highly desired that three phase induction motor works adrift from these all types of fault. Induction motor protection system circuit and its working. Today the most extensively used motor in the industry is the induction motor. The performance of the protection system proposed is discussed by means. With these requirements, the number of singlephasing motor burnouts are greatly. This selection is based on the fundamental ac motor operation processes. For nonessential service motor protection, either long time over current relay protection or direct acting tripping are used to disconnect a motor from its sources of supply in the event of overload. It requires less maintenance as compared to other electrical motors. An induction motors rotor can be either wound type or squirrelcage type. Induction motor protection system all three phases are rectified, filtered, and regulated and given to an operational amplifier where this supply voltage is compared with a certain voltage.
Singlephase induction motor threephase induction motor singlephase induction motor there are probably more singlephase ac induction motors in use today than the total of all the other types put together. Sel motor protection relays give customers a custom fit motor protection system with easy. Sel motor protection relays give customers a custom fit motor protection system with easy installation, for both retrofit and new application. The block uses the threephase input voltages to regulate the individual phase currents, allowing control of the motor torque or speed. Protection of over voltage in over voltage protection system of three phase induction motor protects the motor from over voltage, the. Three phase induction motor protection system using pic. Three phase induction motor protection scheme irjet. Diagnostics of rotor and stator problems in industrial. It also provides a protection system is very important in industries, using lot of motors such that production is not hampered owing to failure of any motor. Induction motor protection system abstract the project is designed to protect an induction motor from single phasing and over temperature. The rotor of an induction motor can be a squirrel cage rotor or wound type rotor.
This system is based on s low cost electronic device that can acquire and preprocess current, voltages and temperatures, and transmit processed keyinformation related to the motor operation condition using zigbee wireless technology. An on line protection system for induction motors was achieved easily and effectively. This bachelor thesis is focused on induction motor protection problems. Squirrel cage induction motor is most widely used in power stations and industries.
The protection system should protect the from voltage. Induction motor protection system circuit and its working elprocus. Microcontroller, monitoring technique, overheating, over voltage, phase reversal, single phasing, three phase induction motor, under voltage etc 1. Protection of induction motor free download as powerpoint presentation. Ac motors need to be protected but protection selection usually does not depend on the motor and load type. It acts as a covering and it provide protection and mechanical strength to all the inner parts of the induction motor. For complete protection, the three phase motor should have an overload element in each phase. Diagnostics of rotor and stator problems in industrial induction motors by fang duan b. The protection is very important to detect abnormal motor running conditions such as over current, over voltage, overload, over temperature, and so on. Induction motor fault detection, protection and speed. These faults are monitored by the protection system and if any fault occurs the motor automatically turned off.