We think you have liked this presentation. If you wish to download it, please recommend it to your friends in any social system. Share buttons are a little bit lower. Thank you!
Presentation is loading. Please wait.
Published byErica Prevost
Modified over 2 years ago
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Voltimum Expert Topic – Power Harmonics
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK What are Harmonics? They are waveforms with frequencies that are multiples of the fundamental frequency (Typically 50Hz in UK & Europe, 60Hz in North America)
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Causes of Harmonics Harmonic currents are caused by the use of non-linear loads: –Switched mode power supplies –HF fluorescent ballasts –Inverters Variable frequency drives UPS systems
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK What do Harmonic waveforms look like? The following 4 graphs show how complex waveforms develop when harmonics are present. Fundamental Waveforms Fundamental + 2 nd Harmonic Fundamental + 3 rd Harmonic Multiple Harmonics Remember the heating effect of the current flowing in the circuit is directly proportional to the area within the curve.
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Waveforms - Fundamental Fundamental Wave, 50Hz
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Fundamental + 2nd harmonic Waveform resulting from the fundamental plus the 2 nd Harmonic Note this shows little effect on the area within the curve compared to the fundamental
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Fundamental + 3rd harmonic Waveform resulting from the fundamental plus the 3rd Harmonic Note the substantially increased area within this curve compared to the fundamental. This effect is seen with all odd number harmonic conditions (e.g. 3 rd, 5 th, 7 th etc )
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Multiple harmonics These waveforms represent the effect of multiple harmonics. Interestingly all these waveforms can represent the same content of harmonic distortion! Note – above the 9 th harmonic the distortion and therefore the heating effect is minimised
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Typical Current waveform of Switched mode power supply
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Some of the Effects of Harmonics Excessive heating in rotating machines –Causing premature failure and risk of fire Excessive currents in the phase and neutral conductors –Causing overheating and risk of fire Overloading of transformers, capacitors and other fixed loads –Causing premature ageing and degradation of function Overloading of switchgear and cables –Leading to unwanted tripping of protective devices Damage to sensitive electronic equipment –Leading to loss of functionality
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Selecting Protective Devices Points to consider in selecting Protective devices when Harmonics are present. 1.Heating effect 2.Shape of waveform
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Selecting Protective Devices 1.Heating effect on Protective Devices The thermal element of devices such as MCB’s, MCCB’s and HRC Fuse links will respond to the heating effect caused by the harmonic content. If incorrectly selected or set this will lead to unwanted tripping or premature ageing. 2.Shape of Waveform Today’s electronic protective devices measure the true RMS current flow which takes into account the harmonic content rather than responding to the heating effect. The measurement of this true RMS can be affected by the shape of the waveform ….. Reference to manufacturers data is recommended when selecting these devices.
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK How to Accommodate the effects of Harmonics Neutral sizing Odd series ( particularly the 3 rd ) harmonics within a three phase system do not ‘cancel - out’ but accumulate within the neutral conductor. This can lead to rms current values equal to and in some cases, greater than that of the phase conductor currents even in balanced load conditions. If a system is affected in this way, then neutral conductors throughout the installation should be sized accordingly
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK How to Reduce the Effects of Harmonics Good design practice is to look at methods to reduce harmonic content rather than to accept it. This could include the addition of one or more of the following:- –Passive filters –Active harmonic conditioners –Transformer based solutions
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Passive filters Capacitor and reactor combination Tuned to specific frequency (typically 189Hz) Requires higher voltage capacitors Designed for a fixed system requirement
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Active harmonic conditioner Harmonic current compensation, 2 nd to 25 th Harmonic neutral current compensation Global or selective harmonic current compensation Site adjustable compensation parameters
Copyright© Voltimum Experts – not to be reproduced without prior consent of Voltimum UK Transformer based solutions 3rd Harmonic rejection transformers Phase shifting transformers Isolation or harmonic suppression transformers
Voltimum Expert Topic – Power Harmonics. What are Harmonics? They are waveforms with frequencies that are multiples of the fundamental frequency (Typically.
© 2003 Eaton Corporation. All rights reserved. Understanding Harmonics Richard Molloy Technology Sales Manager, Power Quality.
Mike Thornton National Sales Manager
QUALITY AND TECHNOLOGY
Siemens Building Technologies Building Technologies Variable Frequency Drives Harmonics Overview.
© Copyright 2008 ABB. All rights reserved /29/2008 Results-Driven Roadshow Cincinnati, 2008 Common Cures for Harmonics Larry Stanley RSE,Nashville,TN.
POWER QUALITY BACKGROUND & ELEC-SAVER TVSS
Understanding of Harmonics in Power Distribution System
Power Quality Issues. Basic Requirements for Critical Loads Continuous, No Break in Power Voltage Regulation Sine wave Supply Isolation Constant Frequency.
PRODUCTS TRANSFORMERS ENERGY SAVING TRANSFORMERS (EST) TRANSFORMER RECTIFIER UNITS 3 rd HARMONIC REJECTION TRANSFORMERS (HRT) ULTRA HIGH ISOLATION TRANSFORMERS.
Dry type transformers Zaragoza Traction application
ISA Northern California Section, South Bay October 14, 2003 Craig Chidester
Power Distribution Harmonics Case Study of 285-3F Chiller Plant Michael W. Harmon Principle Engineer Savannah River Nuclear Solutions, LLC Savannah River.
EMC in Electrical Power Systems Frithiof Jensen Power System Engineer November 12, 2013.
REVIEW OF CFL AND ITS HARMONIC IMPACT ON ELECTRICAL DISTRIBUTION SYSTEM Guide: Mr. Rijo Rajan, prepared by: Merin Lukose Lecturer, S7 EEE EEE department.
VLT ® Low Harmonic Drive. | Property of Danfoss Drives A/S | Tuesday, 15 September 2015 | 2 Acoustic noise Planes, trains, automobiles, busses, construction.
Problem Solving Part 2 Resonance.
Dc regulated power supply SKN. Introduction All electronic circuits need DC power supply either from battery or power pack units. Many electronic equipment.
2010 ASHRAE Rocky Mountain Chapter VFD Fundamentals April 16, 2010 Jeff Miller - ABB © ABB Month DD, YYYY | Slide 1 1.
1 POWER QUALITY -- Bhanu Bhushan -- June, How close is the supply voltage waveform to sinusoidal, and how close are the supply voltage and frequency.
Harmonics and PFC The love story By Pol Nisenblat.
Electrical Distribution Systems
QUALITY & TECHNOLOGY HARMONIC PROBLEMS IN CAPACITOR BANKS.
Applied Harmonics Control of Harmonics
VARIABLE SPEED DRIVES HARMONIC EFFECTS & EFFECT OF USE WITH LONG CABLES (100 – 300m) Electric Motors & Drives ….OUR VISION, YOUR SOLUTION ……. TOGETHER.
7/08/2002PP.AFD.07 Harmonic Quality1 of 49 Yaskawa Electric America Harmonic Currents, Voltages and Your Building Power System.
Power Electronics 2 (H5CPE2) Dr Christian Klumpner Power Electronics, Machines and Control Group School of Electrical and Electronic Engineering, UoN Tower.
Unit 29 Three-Phase Transformers. Objectives: Discuss the construction of three-phase transformers. Discuss the formation of a three-phase transformer.
1 POWER QUALITY -- Bhanu Bhushan -- April, Simple examples around us : Ceiling fan regulators Tube lights Lap-tops & peripherals Domestic inverters.
EXPERIMENTAL STUDY AND COMPARATIVE ANALYSIS OF TRANSFORMER HARMONIC BEHAVIOUR UNDER LINEAR AND NONLINEAR LOAD CONDITIONS.
Active Power in 1~AC mains Apparent / Reactive / Active Power ~ L ~ C ~ R pure resistor R : phase shift = 0° active power 1 pure reactance L : phase shift.
INVERTERS (DC-AC Converters).
POWER SUPPILES LECTURE 20.
1 Chapter 3 Harmonic Modeling of Networks Contributors: T. Ortmyer, C. Hatziadoniu, and P. Ribeiro Organized by Task Force on Harmonics Modeling & Simulation.
7154 VFD Presentation #2 May 2002 Paul Weingartner.
Chapter 3 Power System Harmonic Mitigation. INTRODUCTION Power system harmonic issues have existed since the early 1900 ’ s. The earliest discovered issues.
Three-Phase AC machines Three-Phase Cage Rotor Induction Motor – Electronic Methods of Starting and Speed Control Resource 4.
Applying Harmonic Solutions to Commercial and Industrial Power Systems
POWER SYSTEM PROTECTION. Power system Generators Transformers Transmission lines »Underground cables »Overhead lines Distribution systems.
IEEE PES General Meeting, Tampa FL June 24-28, Chapter 3 Harmonic Modeling of Networks Contributors: T. Ortmyer, C. Hatziadoniu, and P. Ribeiro.
J.PRAKASH. The term power quality means different things to different people. Power quality is the interaction of electronic equipment within the.
Copyright © 2008 Rockwell Automation, Inc. All rights reserved. Direct-to-Drive Technology Product Feature Overview.
BASICS OF BALLAST TECHNOLOGY
ECE Electric Drives Topic 10: Cycloconverters Spring 2004.
Chapter 14: Amplifiers & Oscillators. Amplifiers: Overview Circuits which increase: voltage or current – Take small input signal to reproduce output waveform.
EKT214 - ANALOG ELECTRONIC CIRCUIT II
Dry type transformers Zaragoza Drives application
Single-phase half-bridge inverter
Application of Power Electronics
© 2017 SlidePlayer.com Inc. All rights reserved.