TESTING MOTOR AT LOW VOLTAGE AND SEVERAL FREQUENCIES MOTOR 20 HP, 230 VOLTS,1800RPM, TESTING VOLTAGE 10VAC.

Slides:

Advertisements

Similar presentations

Stator Voltage Control

Advertisements

ENERGY CONVERSION ONE (Course 25741)

Alternating-Current Circuits

Unit 21 Capacitance in AC Circuits. Objectives: Explain why current appears to flow through a capacitor in an AC circuit. Discuss capacitive reactance.

Chapter 24 Three-Phase Systems.

Chapter 12 RL Circuits.

ELECTRIC DRIVES Ion Boldea S.A.Nasar 1998 Electric Drives.

Sinusoidal Waves. Objective of Lecture Discuss the characteristics of a sinusoidal wave. Define the mathematical relationship between the period, frequency,

Power System Fundamentals

Electronics Inductive Reactance Copyright © Texas Education Agency, All rights reserved.

SYNCHRONOUS MACHINES SUBMITTED BY: Ms. APOORVA KANTHWAL

Q31.1 A resistor is connected across an ac source as shown. Which graph correctly shows the instantaneous current through the resistor and the instantaneous.

ELECTRIC CIRCUIT ANALYSIS - I

ECE Electric Drives Topic 11: Slip-Recovery Drives for

The average ac power (P av ) is the power dissipated on the load resistor. 0  cos  1, dependent on the complex load. ideal power factor: cos  =1,

Today’s Topics 1- The per unit system 2-Transformer Voltage Regulation

Filter & Transfer Function Z1Z1 Z2Z2 V in V out To determine filter type, look how H V as a function of frequency Z 1 and Z 2 could include multiple components.

INDUCTION MOTOR steady-state model

ECE 4411 Series-Impedance Starting. ECE 4412 Impedance Z is either an Inductor or a Resistor to limit the current during start-up.

Transformer Voltage Regulation Fact: As the load current is increased, the voltage (usually) drops. Transformer voltage regulation is defined as:

R,L, and C Elements and the Impedance Concept

Lesson 19 Impedance. Learning Objectives For purely resistive, inductive and capacitive elements define the voltage and current phase differences. Define.

Induction motor1 AC Machine Stator ‘a’ phase axis ‘b’ phase axis ‘c’ phase axis

Copyright © 2009 Pearson Education, Inc. Lecture 10 – AC Circuits.

AC POWER ANALYSIS Tunku Muhammad Nizar Bin Tunku Mansur

RC (Resistor-Capacitor) Circuits AP Physics C. RC Circuit – Initial Conditions An RC circuit is one where you have a capacitor and resistor in the same.

ECE 2300 Circuit Analysis Dr. Dave Shattuck Associate Professor, ECE Dept. Lecture Set #24 Real and Reactive Power W326-D3.

(You may use the book and/or notes) 1.Find C T 2. Using V C = V S (1 - e -t/  ), what is the voltage across a capacitor at 10 seconds if R = 5Ω, C=2F,

Chapter 33 Alternating Current Circuits CHAPTER OUTLINE 33.1 AC Sources 33.2 Resistors in an AC Circuit 33.3 Inductors in an AC Circuit 33.4 Capacitors.

Copyright © 2009 Pearson Education, Inc. Chapter 30 Inductance, Electromagnetic Oscillations, and AC Circuits.

Topic 12: Electromagnetic induction 12.2 Alternating current

1 AC Electricity. Time variation of a DC voltage or current 2 I V Current Voltage time t.

1 Chapter 11 AC Power Analysis 電路學 ( 二 ). 2 AC Power Analysis Chapter Instantaneous and Average Power 11.2Maximum Average Power Transfer 11.3Effective.

Chapter 7 AC Power Analysis

Alternating Current Circuits. Resistance Capacitive Reactance, X C.

Intro to AC. AC Alternating Current Flows in two directions. It can reverse many times per second. Intro to AC.

(C) 2006, SUCCESS by DESIGN Surge Values at Each Test Stator surged to fault Indicates decrease in dielectric strength following each test. Applied Surge.

Here is that in-class problem reprised plus, a second example. You should review your notes from that day’s class, as well as Section 24.5 and the associated.

Chapter-23 Alternating Current Circuits. AC Circuits All the equipment in this operating room use alternating current circuits.

Vadodara Institute of Engineering kotanbi Active learning Assignment on Single phase AC CIRCUIT SUBMITTED BY: 1) Bhatiya gaurang.(13ELEE558) 2)

V s N s V p N p = 1. What is mutual induction, how does it work? 2. What is self induction, how does it work? 3. What is the significance of the turns.

Inductance and Inductive Reactance Inductance - the characteristic of an electrical ckt that oppose any change in current Symbol is “L” measured in a Henry.

1 ELECTRICAL TECHNOLOGY EET 103/4  Define and explain sine wave, frequency, amplitude, phase angle, complex number  Define, analyze and calculate impedance,

Fig 33-CO These large transformers are used to increase the voltage at a power plant for distribution of energy by electrical transmission to the power.

Slide 1Fig 33-CO, p Slide 2Fig 33-1, p the basic principle of the ac generator is a direct consequence of Faraday’s law of induction. When.

Induction Motors Equations, Performance, Electrical Equivalent Circuits.

Lecture 03: AC RESPONSE ( REACTANCE N IMPEDANCE ).

AC POWER ANALYSIS. 2 Content Average Power Maximum Average Power Transfer Complex Power Power Factor Correction.

Current flow versus Electron flow Conventional current flows this way. Electrons flow this way.

Inductive Reactance Topics Covered in Chapter : How X L Reduces the Amount of I 20-2: X L = 2πfL 20-3: Series or Parallel Inductive Reactances 20-4:

4-2-2 Passive filters. Passive filters At the end of this topic you will be able to; recognise, analyse, and sketch characteristics for a low pass and.

1© Manhattan Press (H.K.) Ltd Series combination of resistors, capacitors and inductors Resistor and capacitor in series (RC circuit) Resistor and.

Chapter 11 Electronics Fundamentals Circuits, Devices and Applications - Floyd © Copyright 2007 Prentice-Hall Chapter 11.

Chapter 12 RL Circuits.

Equations, Performance, Electrical Equivalent Circuits

Unit – IV Starting and Speed control of Three phase Induction motor

Unit – IV Starting and Speed control of Three phase Induction motor

Lesson 22: AC Power Factor and Power Factor Correction

Induction motor control

3rd European Conference on Renewable Energy Systems (ECRES 2015)

An {image} series circuit has {image} , {image} , and {image}

PowerPoint Presentation for ER 2030

Electric Circuits Fundamentals

Basic Electrical Calculations

Resistance in Series and Parallel

AC Drives Dr. Adel A. El-Samahy Department of Electrical Engineering University of Helwan.

Equations, Performance, Electrical Equivalent Circuits

Unless stated otherwise all AC voltage & current values are rms values

Chapter 33 Problems 3,10,17,21,22,26,32,33,37.

Presentation transcript:

TESTING MOTOR AT LOW VOLTAGE AND SEVERAL FREQUENCIES MOTOR 20 HP, 230 VOLTS,1800RPM, TESTING VOLTAGE 10VAC

CONDITIONS: The voltage source was a sine wave inverter. The voltage was kept sinusoidal by variation of the capacitance between 40  F to 300  F. The current was monitored on 1 Ohm resistor in series with the winding. Both voltage and current were fed to the two channel analyzer. The watts were calculated from the collected data in Excel. Following slide is a sample of the voltage wave form on the terminals of the tested motor. You can notice that the distortion was very low.

Voltage at 300Hz

TEST RESULTS Following are several graphs showing the impact of the frequency while the voltage is kept constant at 10 Vac. Note that some trend-lines are shown with analytical equations (blue thin lines). The analytical equations can be compared to what would be expected under simplified conditions.

Current=f (frequency)

Comment: Though the test was also performed at 60 Hz, it is impossible to make a reasonable graph, because the current is so much higher (looks like a hockey stick). The current at 60 Hz was 4.77 Amps One would expect decreasing the current with the power of –1. Compare to the power of the trend-line: It means the current is dropping with frequency at much slower rate.

Watts = f [frequency]

Comments: In case of a linear circuit, the curve should be dropping with the power of –2. However it is not the case. The watts drop very slowly with the power of – The effect of iron at high frequencies is really profound. The watts at 60Hz: W (and 10 V ac).

COMPARISON OF THE TOTAL WATTS TO THE WATTS LOST IN THE RESISTANCE OF THE STATOR WINDING

Comments: The watts in the copper of the winding were calculated as: P=RI^2. The resistance R from line to line was Ohm. For comparison, the total losses at 60 Hz were W. The loss in the stator winding only was 4.7 W. (60 Hz) Notice how much closer those numbers are compared to higher frequencies. It is obvious, that those two curves have to meet at one point at zero frequency. For the ease of the comparison a ratio was created from those two sets of watt readings. The ratio r = (W-RI^2)/RI^2. W are the total watts.

Ratio r = f [f]

Comments: Note that the ratio for e.g. 800 Hz is about 70. It means that the losses other than those in the stator winding were 70 times higher. For the comparison, the ratio for 60 Hz was only This curve shows clearly, how much different the low voltage is from the conditions at normal operation. The next slide will show the inductance, once calculated from the McKinnon-Smolleck formula and once from the correct formula (REAL).

INDUCTANCE AS A FUNCTION OF FREQUENCY

Comments: The inductance of the circuit is far away form being a constant. The formula for calculating the inductance: The formula takes into consideration all losses P in the circuit. The inductance at 60 Hz was only mH (10 VAC). This inductance drops further to 4.45 mH at 50 V (60 Hz).

Phase Angle = f [frequency]

Comments: It is remarkable,that the phase angle is virtually constant with frequency. It would be interesting to perform the same test on the motor with open rotor slots.