POWER QUALITY. Is it real? Prat Nagu, E.I.T. CTC Engineering, Inc. Ann Arbor, MI

Transcription

1 POWER QUALITY Is it real? Prat Nagu, E.I.T. CTC Engineering, Inc. Ann Arbr, MI

2 Why shuld we care? Cmputer Lckuts (20%) Light flickering (22%) Electrnic failures (18%) Pwer factr crrectin system failures (17%) Failures in high lad switching (16%) Neutral cnductr verheating (12%) Unexpected breaker peratin (11%) Pwer meters inaccurate readings (6%) And f curse excess lsses and dwntime CTC Engineering, Inc. 10/11/2017 2

3 Typical PQ Issues CTC Engineering, Inc. 10/11/2017 3

4 Chicken r the egg? Lads distrt current wavefrms In turn causes vltage distrtin CFL Vltage Distrtin System Impedance Amunt f distrted current VFD Current Distrtin CTC Engineering, Inc. 10/11/2017 4

5 Surces f PQ prblems Utility Lightning Pwer Factr Crrectin Faults Switching End User Individual Lads Lighting lads Elevatrs Clers UPS VFD Battery Chargers Large Mtrs during start up Electrnic Light Dimmers Electrnic Light Ballasts Arcing Equipment Welding Steel manufacturing Medical Equipment MRI, X-Ray, etc. Office equipment and Cmputers Switch Mde Pwer Supply (SMPS) Imprper Electrical System Design Wiring CTC Engineering, Inc. 10/11/2017 5

6 Wavefrm Distrtin Effect f a simple residential light dimmer n current waves Nw think abut the number f residential/ cmmercial lads and the number f electrnics lads that disrupt the wavefrms CTC Engineering, Inc. 10/11/2017 6

7 Causes and Slutins PQ Prblems Majr Surces Slutins Frequency The Utility Interruptins The Utility Vltage variatins Lad changing Synchrnus lads Fast PF crrectin Vltage flicker Lad change (welding) Fast PF crrectin Vltage dip Mtr and heavy lad start up Mtr Starters VFD Fast PF crrectin Over vltage Over PF cmpensatin Fast PF crrectin Transients Start up r Switching Cntrlled switches Unbalance Unbalanced lads, phase shift Balance the lads Harmnics Nn linear lads Resnance Active passive filters Detuned capacitrs Imprved VFD peratin CTC Engineering, Inc. 10/11/2017 7

8 Harmnics CTC Engineering, Inc. 10/11/2017 8

9 Harmnics Furier Analysis CTC Engineering, Inc. 10/11/2017 9

10 THD r TDD? CTC Engineering, Inc. 10/11/

11 Expected Harmnics in VFDs What rder f harmnics t expect frm yur VFD? H = np ± 1 E.g.: 6 pulse VFD: 5, 7, 11, 13, 17, 19 Generally magnitude decreases as rder increases Expected harmnics: SMPS 3, 5, 7, 9, 11, 13 Flurescent lights 3, 5, 7, 9, 11, 13 Arcing devices 2, 3, 4, 5, 7 Transfrmer energizatin 2, 3, 4 CTC Engineering, Inc. 10/11/

12 If yu cannt measure it, yu cannt manage it CTC Engineering, Inc. 10/11/

13 Case Study Steel Plants G Industry A Industry B Traf Rating 5 MVA 5 MVA Demand 3.5 MVA 4.9 MVA %THDv %THDi CTC Engineering, Inc. 10/11/

14 Case Study Steel Plants Timestamp Phase A Phase B Phase C %THDv with Industry-A lads OFF 15:36: :36: :37: %THDv with Industry-A lads ON 15:37: :37: :37: :38: :39: :40: :41: :41: :42: :43: :43: CTC Engineering, Inc. 10/11/

15 Triplen Harmnics They add up and return as neutral current CTC Engineering, Inc. 10/11/

16 Triplen Harmnics Neutral Cnductr CTC Engineering, Inc. 10/11/

17 Ecnmic impact Oversizing f equipment Lsses thrugh inefficiencies PF penalties Incnsistent meter reading Cst assciated with dwntime due t Equipment failure Frequent repairs/ maintenance Cst fr adding harmnic filters CTC Engineering, Inc. 10/11/

18 If yu cannt measure it, yu cannt manage it CTC Engineering, Inc. 10/11/

19 Mnitring Optins Temprary CTC Engineering, Inc. 10/11/

20 Mnitring Optins Wireless New CTC Engineering, Inc. 10/11/

21 Wireless & Online PQ Mnitr CTC s latest R&D prject Striking Features: Plug and Play Wireless cmmunicatin Cyber secure Elegant, User friendly, Anywhere HMI Mnetizatin and Predictin Multi-nde mnitr All-in-ne Pwer Quality Mnitr Prttypes are already ut! Applicatin: Utilities Municipalities Industrial Substatin Pwer Plants Manufacturing facilities Prcess Industries - WWTP Hspitals Universities T find ut mre stp by at CTC Bth! CTC Engineering, Inc. 10/11/

22 Thank yu! Visit ur bth, we are here till tmrrw CTC Engineering, Inc. 10/11/