IEEE Standard 519-2014

[Pages:50]IEEE Standard 519-2014

Compliances, Updates, Solutions and Case Studies

Presented by: Dr John Cheng, CEng, CEM, CEA, CMVP

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Agenda

1. Introduction: Harmonics Overview 2. History of IEEE STD 519, and comparison between

IEEE STD 519 (2014 vs 1992) 3. How SE helped you to achieve IEEE STD 519-2014 4. Case Studies 5. Conclusions

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Introduction

Harmonics Overview

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Why is there harmonic in the electrical network?

Linear loads versus Nonlinear loads

Linear loads:

Nonlinear loads:

DC

AC

AC

Power electronics switches

Diode Thyristor MOSFET BJT IGBT

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Source: IEC 61000-3-6:1996

How does the harmonic created?

Single phase full-bridge rectifier circuit

U

iC

iC

i V

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DC bus voltage U

DC bus capacitor current (IC)

Supply current

(i)

Supply voltage (V)

V = E - Zsi

"Evolution" of Power Factors

With linear vs. nonlinear loads

Electrical system with ONLY linear loads

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Electrical system with Nonlinear loads

S = kVA (Apparent Power)

Q = kVAr (Reactive Power)

TPF (True/Total Power Factor) P = kW (Real Power)

D = kVAH (Distortion Power)

S kVA Vrms I rms P 2 Q 2 D 2

True/Total Power Factor : cosTPF cosdispPF cosdistPF

Displacement Power Factor (Fundamental Components):

cos d isp PF

kVA(

kW fundamental)

Distortion Power Factor (Harmonic Components):

cosdistPF

1 1 THDv2 1 THDi2

Effects of Harmonics

Different Perspectives

Engineering Perspective ? Nuisance tripping of circuit breaker ? Harmonic resonance ? Capacitor bank failure ? Excessive heating ? Transformer overheating ? Skin effects on cables for higher harmonic orders ? Motor winding burnt (dv/dt) & hunting ? Neutral overloading (double neutral) ? Causing EMI to sensitive signals ? Problems to generators

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Business Perspective ? Increased maintenance and replacement cost (OPEX) ? Interruptions and downtimes cost ? Reduced system capacity and thus increase CAPEX by

unnecessary of expansion.

History of IEEE Standard 519

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