# starting problems and solutions of induction motor

The characteristics of an induction motor, the speed, current, starting torque, maximum torque, the motor losses and efficiency can all be determined from an analysis of the equivalent circuit. A Three-phase Induction Motor Problem This application note describes how to set up, solve, and analyze the results of a two-pole, three-phase induction motor using RMxprt. The diﬃcult ones are marked with an asterisk. Ω, X. Problem Solving Investigation. Different Types of Starters for Induction Motor (IM) Starting Methods for Single-phase Induction Motor; DC Machines. Mathematical Induction Problems With Solutions : Here we are going to see some mathematical induction problems with solutions. Induction motors work by generating rotation power through electrical conversion. The starting current of an induction motor is. Determine if the problem is isolated to one motor circuit or common to the entire facility. Induction Machines's Previous Year Questions with solutions of Electrical Machines from GATE EE subject wise and chapter wise with solutions Where, V L is line voltage. Why High Starting Currents: A COMPUTER SIMULATION BY ETAP POWER STATION. Line Current iv. This is with interacting magnetic fields. View this answer. • The stator works as the primary while the rotor works as the secondary. Ω, X. m. i. Synchronous speed in rpm =30.74 . -The main problem in split-phase induction motor is low starting torque, as this torque is a function of, or related to the pha se difference (angle) between th e currents in the two w indings. d) Output torque. STARTING ANALYSIS OF INDUCTION MOTOR. c) Output power. To limit the starting current surge, large induction motors are started at reduced voltage and then have full supply voltage reconnected when they run up to near rotated speed. Record all nameplate information for the induction motor. Chapter , Problem is solved. For this, damper windings are used. As soon as motor achieves certain speed, motor winding is connected in delta fashion such that line voltage is equal to phase voltage with the help of two way switch. b. less than the full-load current. The ends of the copper bars are short-circuited. 1. Ω Rotational losses are 2450W. This will link and cut the rotor conductors which in turn will induce a current in the rotor conductors and create a rotor magnetic field. c. greater than the full-load current. AC MOTOR: INDUCTION MOTOR Most common motors in industry Advantages: Simple design Inexpensive High power to weight ratio Easy to maintain Direct connection to AC power source 5. Find the percentage slip and number of poles of the induction motor. Therefore different starting of induction motor, methods such as (star delta starter, auto transformer starter and other starting methods) are employed in order to reduce the high starting currents of induction motor. The problem I am having with it is a slow acceleration from dead stop to a speed at which the repulsion mechanism disengages. An induction motor's rotor can be either wound type or squirrel-cage type. It took 4-5 sec on the bench with no load and now when … These advantages in induction motors make them more prominent in industrial and domestic applications. Piyush S. Patil, ... can poses a problem to both the utility and the customer. 1 =0.507 . Here are a collection of statements which can be proved by induction. 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. I have a 1hp 110V single phase Wagner repulsion start induction run motor on my Royersford 21" drill press. Not sure if this is the original motor or not but I have seen others with similar looking motors. Consideration about problems and solutions of speed estimation method and parameter tuning for speed-sensorless vector control of induction motor drives It supplies an induction motor ich has a full load speed of 144wh 0 rpm. Speed and Direction of Rotation . 2 =0.309 . Direct starting of large scale three-phase induction motor may cause voltage dip or more trouble at the point of common coupling whichmay affects the neighbor's electrical supply or it may damage their devices. Induction motors rely on the interaction of magnetic fields to convert electrical power into rotating power. Step-by-step solution: Chapter: Problem: FS show all show all steps. Methods of Starting Three Phase Induction Motors As we know, once a supply is connected to a three phase induction motor a rotating magnetic field will be set up in the stator, this will link and cut the rotor bars which in turn will induce rotor currents and create a rotor field which will interact with the stator field and produce rotation. As such, this book concentrates primarily on the application of motor starting in connection with induction motors. Induction Motors Solution Problem (1): The per-phase parameters of the equivalent circuit, for a 400V, 60Hz, 3 phases, Y-connected, 4 pole induction motor are: R 1 =2R 2=0.2 Ω X 1=0.5 Ω X 2=0.2 Ω X m=20 Ω If the total mechanical and iron losses at 1755 rpm are 800 W, calculate: a) Input current. Define mathematical induction : Mathematical Induction is a method or technique of proving mathematical results or theorems. An induction motor therefore does not require mechanical commutation, separate‐ excitation or self‐excitation for all or part of the energy transferred from stator to rotor An induction motor's rotor can be either wound type or squirrel‐cage type. A few are quite diﬃcult. We need to give double excitation to make a DC motor to rotate. Electric Motor Problems. In the DC motor, we give one supply to the stator and another to the rotor through brush arrangement. In this method, the motor is first started as an induction motor and then starts running as a synchronous motor after achieving synchronous speed. Nuisance tripping of a motor-protective device. High resistance is often encountered when starting a motor from a static (idle) position, and excessive current draw is necessary to begin rotation of the motor shaft. Working Principle of Induction Motor . Motor are a collection of statements which can be either wound type or squirrel-cage type repulsion induction. 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