STATCOM ADF Conference Jonas Persson Comsys AB September 16th Comsys ADF Power Tuning 1
Power isn t perfect Comsys ADF Power Tuning 2
STATCOM, System Integration Agenda STATCOM Introduction to STATCOM Hybrid STATCOM concept How-to-guide Selected References Comsys ADF Power Tuning 3
STATCOM Introduction Static synchronous compensator VSC based (Voltage Source Converter) Traditionally, reactive power only (all quadrants) If connected to energy supply, can generate active power Faster, more complex than SVC (Static VAR Compensator) Comsys ADF Power Tuning 4
STATCOM Applications Dynamic Reactive power usable for: Compensating cable capacitance Stabilize voltage DVR applications Flicker reduction Other grid applications Comsys ADF Power Tuning 5
STATCOM: VSC Converter part (green) Identical to what is being used in 2- level active filters and drive inverters (if using IGBT) Maximum IGBT blocking voltage typically 6500V IGCT is also an option Blocking voltage presents major challenge! Line filter (red) Image shows L-filter; in ADF always LC or LCL Scales perfectly with current and voltage Comsys ADF Power Tuning 6
STATCOM: VSC:: High voltage Voltage limits of converter With 2-level, maximum native line voltage <3kV Multi-level converter increases this to approx. 6.6 kv How to increase voltage tolerance? 1. Series connection (shown) 2. Transformer Comsys ADF Power Tuning 7
STATCOM: VSC:: High voltage 1. Series connection Series connection requires exact concurrent ignition of IGBT (depending on equivalent inductance in connecting cable) or single IGBT will take all the voltage IGBT failure! 2. Transformer This is a simple solution but may degrade efficiency; adding transformer losses to converter losses. Or? Comsys ADF Power Tuning 8
STATCOM: VSC:: High voltage 1. Series connection Series connection requires exact concurrent ignition of IGBT (depending on equivalent inductance in connecting cable) or single IGBT will take all the voltage IGBT failure! Medium voltage series connected IGBT: prohibitive complexity! Image courtesy of ABB. Used without permission Comsys ADF Power Tuning 9
STATCOM: VSC:: High voltage 2. Transformer Transformer is in itself an inductive component By custom-making the transformer, the secondary inductance can be utilized as part of line filter! ADF units are then equipped with custom LC line filter This is what we did on the first ADF P700 TRAFO1 Y Y Y Y YNyn 0 22.5kV/690V 2000kVA 8% Dry MCC1 PPC1-1 PPC1-2 PPC1-3 PPC1-4 WCSC PPC2-4 PPC2-3 PPC2-2 PPC2-1 MCC2 YNyn 0 22.5kV/690V 2000kVA 8% Dry Comsys ADF Power Tuning 10
STATCOM: LV STATCOM concept Modular, 2x2 MVA solution 690V low voltage switchgear internally easier to service 22 kv main connection MCC1 PCC1-1 PCC1-2 PCC1-3 PCC1-4 WCSC PCC2-4 PCC2-3 PCC2-2 PCC2-1 MCC2 See MCC-M6 PP1 PP1 PP1 PP1 PP1 PP1 PP1 PP1 X30 PP2 PP2 PP2 PP2 PP2 PP2 PP2 PP2 X30 See MCC-M1 See MCC-M1 PP3 PP4 PP5 PP3 PP4 PP5 PP3 PP4 PP5 PP3 PP4 PP5 PP3 PP4 PP5 PP3 PP4 PP5 PP3 PP4 PP5 PP3 PP4 PP5 M4 See MCC- M2, M3, M4 3 See 2 TA-M4 X10 X20 T A 2 3 See PP-M3 T T T T T T T 5 5 A 5 5 A 5 5 A 5 5 A 5 5 A 5 5 A 5 5 A 5 5 X10 X10 X10 X10 X10 X20 X10 X10 X10 X10 X20 X10 M5 See WCSC- M4, M5 See MCC-M1 See PP-M1,M2 See WCSC-M1 Comsys ADF Power Tuning 11
STATCOM: LV STATCOM concept (2) We have supplied LV/HV hybrid STATCOM up to 130 kv so far Scales well to at least 10 MVAr (depending on voltage/project) For very high ratings, LV/HV hybrid solution becomes impractical Comsys ADF Power Tuning 12
STATCOM: How-to-guide Basic idea: stack enough P300 units and connect to large enough transformer! Size according to needed MVAr For flicker projects, rule-of-thumb is to size so that ADF reactive power exceeds load In most cases, custom Transformer/LC-filters are not needed Might be considered in some cases Special care must be taken with transformer, cooling and CT Comsys ADF Power Tuning 13
STATCOM: How-to-guide: components Building blocks: Regular ADF P300 units, or System integration components (PPM300, SCC2, etc; more on this later) Up to 6 modules per computer Up to 0.167 MVAr per module (690V Liquid cooled) In multi-master, max 15 units; 15 computer x 6 modules = 15 MVAr! Multi-master not necessary in all cases Only difference between separate components and complete products is packaging. Comsys ADF Power Tuning 14
STATCOM: How-to-guide: transformer Typically, Yyn or similar straight transformer must be used Cannot be used with non-symmetrical loads Unbalanced loads will overload such transformer For DPF and flicker projects, impedance is selected to give a reasonable short-circuit power For Harmonics projects, transformer must be custom-ordered spectrum to be supplied to transformer mfgr Comsys ADF Power Tuning 15
STATCOM: How-to-guide: switchgear If using P300 units, dedicated switchgear may not be necessary If using gg (or similar fuses), ADF fuses protect connecting cable as well Again, short-circuit current must be taken into account For example, 4MVA @ uk=6% may give up to 100 ka In this case it may be better to divide into two separate transformers Take care to follow local regulation! Comsys ADF Power Tuning 16
STATCOM: How-to-guide: CT Normally use Open Loop configuration STATCOM projects typically pin-point load and/or facility All of Comsys STATCOMs have open-loop configuration! CTs might need to be custom ordered CTs placed on medium voltage do not always have 5A secondary In some cases, LEM current transducers must be used to maintain measurement precision Comsys ADF Power Tuning 17
STATCOM: How-to-guide: cooling Majority of Comsys STATCOM installations are liquid cooled For liquid cooling, system integration concept is presently only option P300W will re-appear Main difference is power density and overloadability in flicker applications Comsys ADF Power Tuning 18
STATCOM: (selected) Reference list Site Year Application Size Voltage Höganäs 2007 EAF/Flicker 2x2 MVAr + 42 MVAr (THY) 22 kv Dantysk 2015 Offshore wind farm (DPF) 4x1.5 MVAr 33 kv Kville 2012 Wind farm/statcom (DPF) 2.5 MVAR 130 kv Lingbo 2012 Wind farm/statcom (Flicker) 1 MVAr 33 kv WDI 2012 Welding/Flicker 2.5 MVAr 20 kv Sandvik 2010 EAF/Flicker 4 MVAr 10 kv Global Casting 2015 Casting/STATCOM (DPF) 4 MVAr 10 kv Comsys ADF Power Tuning 19
ADF the shape of power to come Thank you for your time! Comsys ADF Power Tuning 20
Questions? Comsys ADF Power Tuning 21
Comsys in brief Power Quality expert Global partner Research driven Dedicated to key segments Comsys ADF Power Tuning 22