HV Testing Lab

This laboratory is equipped with ultimate measurement techniques which allow extensive testing of power transformers, instrument transformers and HV switching equipment, including type and special tests in accordance with international standards.

Since 1995, the Laboratory has been accredited by Romanian Accreditation Association- RENAR
(member of ILAC and EA ) according to IEC/ISO 17025.

Annex to the accreditation certificate

LOVAG Registred Laboratory

TESTING Equipments

Impulse generator 4,2 MV; 336 kWs

IMPULSE
lightning 4200 kV(336kWs) 700 kV (4,9kWs)	switching 2600 kV 300 kV

AC
25 Hz to 150 Hz
1200 kV (hall)		1,2 A
1800 kV (outdoor)		1,2 A
50 Hz
200 kV		0,5 A
350 kV		0,75 A
3x250 kV (resonant system)		1 A
(25 to 150) Hz - three phases
15 kV; 35 kV;110 kV	5 MVA	2 min

DC
1100 kV	30 mA

HV Testing Lab consists of:

- a screened high-voltage hall (48 m x 32 m x 27 m) for type and special tests (with 4.2 MV impulse generator, 1.2 MV AC transformer cascade and 1.1 MV DC cascade rectifier, artificial rain equipment);
- a induced voltage hall (36 m x 32 m x 27 m) for routine tests;
- an outdoor test field (30 m x 35 m) for reliability test.

MEASURING TECHNIQUE

High Voltage measuring systems formed of dividers and peak voltmeters
Lightning and switching impulse divider 643/4200 [pF]/[kV] (mounted together with the
generator) according. to IEC 60060-2/94, Amendment 1/96
Response time - 10 ns
Lightning impulse divider 10/2200 [kohm ]/[kV]
Response time - 27 ns
Lightning impulse divider 10/770 [kohm ]/[kV].
Response time - 10 ns
AC capacitive divider 160/1200 [pF]/[kV]
(mounted together with AC cascade)
AC capacitive divider 200/1800 [pF]/[kV] (mounted together with the upper cascade unit in outdoor Field)
Reference measuring systems according to IEC 60060-2 for LI ( SI ), AC , DC voltages and Impulse
Charge for PD measurements, having trasability to PTB
Equipments specialized to record HV transient phenomena (Transient recorder 10 bit, 100 MS/s,
3 channels and Transient recorder 10 bit, 100 MS/s, 2channels)
Equipments specialized to measure partial discharges by electrical and ultrasonic methods, with PD free sources up to 600 kV
Equipment to measure radio interference voltage
Equipment to measure atmospheric conditions during HV test

Servicies offered
The accredited tests for High Voltage Testing Laboratory

SERVICES OFFERED

High voltage tests for HV equipment
(transformers, cables, switchgears, GIS, etc.)
inside the electromagnetic screened hall of ICMET

High voltage tests on site:

- Full wave (1.2 / 50 s ) and tail chopped wave voltage impulse tests (between 2 and 8 s) at voltages up to 4200 kV and energy 336 kWs
- Applied voltage tests at frequencies between 25 and 150 Hz up to 800 kV
- Single and three-phase induced voltage test, 5 MVA, 2 min.
- DC voltage tests uo to 1200 kV 30 mA, up to 1200 kV
- Oscillating switching impulse tests
- Aperiodic switching impulse tests up to 2600 kV
- External insulation test under artificial rain for equipment up to 400 kV rated voltage
- Partial discharge and radio interference measurements
- Combined voltage tests: LI - AC, SI - AC, DC - LI, DC - SI

- AC sparkover voltage test of arresters up to 60 kV
- AC or DC voltage test of high voltage cables up to 100 kV
- AC voltage test of SF6 enclosed stations up to 250 kV (resonant equipment)
- Induced voltage test of distribution transformers
- Switching impulse test for instrument and power transformers by electromagnetic induction
- Partial discharge measurement at instrument and power transformers by electric and ultrasonic method.

The accredited tests for High Voltage Testing Laboratory

Test Type	The main test and / or measuring equipment	Tested item	The reference documents (norms)
1. Lightning impulse test (LI) 1.1 Lightning impulse test (LI) 1,2 / 50 µs	1. Capacitive divider for LI 4.2MV 2. Resitive divider for LI 2,2MV, 10 kOhm 3.Damped capacitive divider 2MV 4.Haefely impulse oscilloscope type 72E, with photographic device, maximum input signal 1500V, with 9 steps, sweep base time (0,1¸ 500)m s/cm 5. AEG impulse oscilloscope type 018, with the photographic device, maximum input signal 700V. 6. Haefely peak voltmeter type 64 m, class ± 1% 7. Peak voltmeter type MUT-7, class ± 1% 8. Impulse peak voltmeter type SMUT-1 9.GIT 700kV max.4,96kWs 10.GIT 4,2MV max.336kWs 11.Sphere gap f 1500mm, vertical position 12. Sphere gap 750mm, vertical position 13. Sphere gap f 250mm, horizontal position 14. Resistive divider for LI, 0,77MV/101 Ohm 15 Digital impulse measuring system for LI type TR-AS 100-10/3.	1.Oil-immersed power transformers up to 400MVA, 400kV class, inclusively	IEC 60-1/89 Sect.6 IEC 60-2/94, Sect.9 IEC 60076-3/2000 IEC 722/82
		2.Dry power transformers up to 3000kVA, 36kV class, inclusively	IEC 60726/82
		3.Current transformers up to 400kV class, inclusively	IEC 60185/1994 IEC 60044-1/96 9.1
		4.Voltage transformers up to 400kV class, inclusively	IEC 60186+A1/96 IEC 60186/87 (capacitive) IEC 60044-2/97 (inductive)
		5. Alternating current disconnectors up to 400kV class, inclusively	EN 60129+A1/96 IEC 62271-100/2001 IEC 60071-1/96 IEC 60694/96
		6. Alternating current circuit breakers up to 400kV class, inclusively	IEC 60071-1/96 IEC 60694/96 IEC 62271-102/2001
		7.Enclosed busbars	IEC 60071-1/93 IEC 60071-2/96
		8. Bushing	EN 60137/98 IEC 60137/95
		9. AC metal-enclosed switchgear and controlgear for rated voltages, above 1kV and up to 72.5kV, inclusively(High-Voltage prefabricated substation).	IEC 60298/1999
		10. Arrester	IEC 60099-1/94 IEC 60099-1/91
		11. a- Reactors	IEC 60289/88
		b- Capacitors	IEC 60358/96 IEC 60358/90
		c- Neutral resistances	SR 6669-2/86
		12. High voltage fuses: current limiting fuses	IEC 60282/1-2002
1.2. Lightning impulse test with measurement of transferred over-voltage from the high-voltage winding to a low voltage winding.	GIT 4,2MV max:336 kWs or low-voltage GIR Capacitive divider 4,2MV Resistive divider 770kV/ 10kOhm Impulse cathodic oscilloscope or digital impulse measuring system type TR-AS 100-10/3.	1. Oil - immersed or dry power transformers up to 400MVA; 400kV class, inclusively.	IEC 60076-3/2000
2. Power - frequency voltage tests. 2.1. Separate - source voltage test (50Hz)	1.DC 1,2MV type WMC+WMUT-3 2.DC 600kV type MCF + WMUT-3 3.DC 350kV type MCF + MU9 4.DC 300kV type MCF+WMUT-3 5.Transformers cascade 1,5MVA; 1200kV 6.Test transformer 350kVA;350kV 7.Test transformer 200kVA; 200kV 8.HV source 1,5kVA; 10/0,22kV 9.Motor-generator group S_max=5MVA; U_max-12kV; f=(25¸ 150)Hz 10.Artificial rain plant 11.Check device of the second figure specific to protection degree (3; 4 and 5).	1.Oil-immersed and dry power transformers up to 400MVA, 400kV class, inclusively	IEC 60-1/89, Sect.5 IEC 60-2/94, Sect.8 IEC 60076-3/2000 IEC 60726/82
		2.Voltage transformers up to 400kV class, inclusively	IEC 60186+A1/96 IEC 60186/87 (capacitive) IEC 60044-2/97 (inductive)
		3. Current transformers up to 400kV class, inclusively	IEC 60185/1994 IEC 60044-1/96
		4. Alternating current disconnectors up to 400kV class, inclusively, dry and wet conditions	EN 60129+A1/96 IEC 62271-100/2001 IEC 60071-1/96 IEC 60694/96
		5. Alternating current circuit-brekers up to 400kV class, inclusively, dry and wet conditions	IEC 60071-1/96 IEC 60694/96 IEC 62271-102/2001
		6. Enclosed busbars	IEC 71-1/93 IEC 71-2/96
		7. Bushing, dry and wet conditions	EN 0137/98 IEC 60137/95
		8. AC metal-enclosed switchgear and controlgear for rated voltage above 1kV and up to 72.5kV, inclusively (High-voltage prefabricate substation), dry and wet conditions.	IEC 60298/99
		9. Arresters	IEC 60099-1/94
		10. a-Reactors	IEC 60289/88
		b-Capacitors	IEC 60358/96
		c-Neutral resistances	EN 60529/95
2.2. Induced over-voltage test (150Hz)	1.Motor-generator group Smax=5MVA; Umax=12kV; f=(25¸ 150)Hz 2.Induced voltage power station 15/35/110kV with following composition a) 3MVA; 22,5(45)± 13x1,445%/6(12)kV power transformer b) 500kVA; 6(12)/125(250)kV power transformer c) 1000kVA; 7,5 ± 30%/1,5 (3)kV power transformer d) TIRBO 20kV/0,1kV; TEMU 35kV/0,1kV; TEMU 110kV/0,1kV instrument transformers 3.DC 300kV type MCF+WMUT-3 4.DC 600kV type MCF+WMUT-3 5.700kV damped capacitive divider	1. Oil-immersed and dry power transformers up to 400MVA, 400kV class, inclusively	IEC 60076-3/2000 IEC 60726/82
2.3.Measurement of the harmonics of the no-load current	Motor-generator group S=5MVA; 6(12)kV; f=50Hz Induced voltage power station 110/35/15kV Wave analyzer Hewlett Packard type 3581.A Power Harmonics Analyzer type Fluke-41	Oil-immersed and dry power transformers up to 400MVA; 400kV class, inclusively	IEC 61000-4-7/91
3. Switching impulse test (SI) 250/2500 µs	1.Capacitive divider 4.2MV 2.Universal RC divider 2MV 3.Resistive divider for LI 2.2MV, 10kOhm 4.Impulse oscilloscope Haefely tip 72E with photographic device, max input signal 1500V, with 9 steps, sweep base time (0,1¸ 500)m s /cm 5.Impulse oscilloscope AEG type 018, with photographic device, input signal max.700V 6. Haefely Peak voltmeter type 64m, clasa ± 1% 7. Peak voltmeter type WUT-7, clasa ± 1% 8.Peak voltmeter type SMUT-1 9.GIT 700kV max., 4,96kWs 10.GIT 4,2MV max., 336kWs 11.Digital impulse measuring system for SI type TR-AS 100-10/3 12. Sphere gap F 1500mm ,vertical position 13. Sphere gap F 750mm, vertical position 14.Sphere gap F 250mm, horizontal position	1.Power transformers up to 400 MVA, 400kV class, inclusively	IEC 60-1/89 IEC 60-2/94 IEC 60076-3/2000 IEC 60722/82
		2.Instrument transformers up to 400kV class, inclusively a-Current transformers b-Voltage transformers	IEC 60185/94 IEC 60044-1/96 IEC 60186+A1/96 IEC 60186/87 (capacitive) IEC 60044-2/97 (inductive)
		3.Circuit-brekers up to 400kV class, inclusively	IEC 62271-102/2001
		4.Current disconnectors up to 400kV class, inclusively	EN 60129+A1/96 IEC 62271-100/2001
4. Measurementr of capacity and tan delta	1.High voltage Schering bridge type SIEMENS 2.Standard capacitor 100pF; 100kV and 200kV 3. AC voltage sources from cr.no.2 4. Screens, flexible metalic tubs	1.Power transformers up to 400MVA, 400kV class, inclusively	SR 6669-1;3/86 SR 1703-7/80
		2. Bushings up to 400kV class, inclusively	IEC 60137/95 EN 60137/98
		3. Capacitors	IEC 60358/90
		4.Instrument transformers	IEC 60185/94 IEC 60044-1/96 IEC 60186-1+A1/96 IEC 60186/87 (capacitive) IEC 60044-2/97 (inductive)
5. Measurement of partial discharge level	1.Voltage sources from cr.no.2 or 3 2.Coupling capacitor Micafil 600kV 3.Partial discharge measuring instruments LMZ, AEG, MTE 4.Calibrating generator: RFT; PET-2 5.Frequency analyzer 6. Tektronix oscilloscope type 2212, 60MHz 7.Ultrasonic detectors type DUDP	1.Power transformers up to 400MVA, 400kV class, inclusively	IEC 60-1,2/89;94 IEC 60076-3/2000 IEC 60270/2000
		2. Instrument transformers up to 400kV, inclusively a) Current transformers b) Voltage transformers	IEC 60044-1/96 IEC 185/94 IEC 60270/2000 IEC 60044-2/97 IEC 60186/87 IEC 60186+A1/96
		3. Bushings	IEC 60270/2000 IEC 60137/95 EN 60137/98
6. Measurement of RIV by conduction and radiation way	1.Voltage sources from crt.no.2 or 3 2.Coupling capacitor Micafil, 600kV 3.Measuring instruments of RIV; LMZ 4.Calibration generator: RFT 5.Frequency analyzer	1.Power transformers up to 400MVA, 400kV class, inclusively	IEC 60-1,2/89/94 NEMA TR 1/1974
6. Measurement of RIV by conduction and radiation way		2.High voltage equipment	IEC 60437/97 IEC 60694/96 IEC 62271-100/2001 IEC 62271-102/2001 CISPR 18-2/86 EN 60129+A1/96 EN 61284/2000
7. Direct current high voltage test up to U_max=1200kV	1.Cascade rectifier, Greinacher mounting circuit with U_max=1200kV; I_max=30mA 2.Resistive divider 1.2MV included in testing equipment	-Electric cables; -Capacitors; -Circuit-breakers; -SF6 enclosed equipment; -Protective rods; -Insulating stairs.	IEC 60-1/89 IEC 60-2/94
8.Emission tests for EMC 8.1 Radio disturbance measurement by conduction at low voltage equipment	1.Artificial network SMZ 5; SMZ 6; 75 Ohm 2.Radio disturbance measuring instrument type SMV 6.1 -0.15-50 MHz; -input impedance 50 Ohm; 75 Ohm -artificial network NNB 103, 50 Ohm/50µH 3.TDS-524 oscilloscope 4.Radio disturbance measuring instrument type SMV 42/98 5.Artificial network 41/98	-Industrial equipment, scientific, medical and electric light equipment -Equipment, systems used in power electronics -Information technology equipment -Household appliances electric tools	CISPR 16-1/1999 CISPR 16-2/1999+A1/99 SR EN 55011/1997 CISPR 14-1/2000 SR EN 55015/1995 CISPR 22/1997+A1/2000
8.2 Measurement of disturbance power by conduction for low voltage equipment	1.Interference electromagnetic receiver SMV 42 2.Absorbing clamp	-Electric motor operated and thermal appliances for household and similar purposes; -Electric tools; -Motor-operated electro-medical apparatus; -Electric toys running on tracks; -Automatic goods dispensing machines and automatic entertaining machines	CISPR 14-1/2000 SE CISPR 16-1:1999 CISPR 16-2/1999+A1/99
8.3 Harmonic current emissions measurements for low voltage equipment	1.Harmonics analyzer and flicker type HAR 1000-1P 2.IBM PC Computer	-Electrical and electronically equipment, including unprofessional arc welding equipment, with an input current less then 16A/ phases which are intended to be connected in low-voltage supply systems.	SR EN 61000-3-2:2001 CEI 61000-4-7:2002
8.4 Voltage fluctuations and flicker measurement for low voltage equipment	1.Harmonics analyzer and flicker type HAR 1000-1P 2.IBM PC Computer	-Electrical and electronically equipment, intended to be use in 220 and 250 V, 50 Hz low voltage supply systems with ratted current less then 16 A/phase and up/subjected at special connection	SR EN 61000-3-3:1998 CEI 61000-3-3:1994 +A1/2001
9.Direct current high voltage test up to U_max=1200kV	1.Cascade rectifier, Greinacher mounting circuit with U_max=1200kV; I _max=30mA 2.Resistive divider 1.2 MV included in testing equipment	-Electric cables; -Capacitors; -Circuit-breakers; -SF6 enclosed equipment; -Protective rods; -Insulating stairs	STAS 6669/1;2;3-86 IEC 60-1/89 IEC 60-2/94
10.Combined voltage test (LI or SI; AC; DC)	1.Impulse generator 4.2 MV + its own capacitive divider 2.Transformer cascade + its own capacitive divider 3.Cascade rectifier 1.2 MV + its own resistive divider 4.Separating capacitor U_n=220kV mounted over an insulated platform for insulating level U=400kV 5.Insulated limiting resistance 17 kOhm 6.Sphere gaps, diameter 250mm, 500mm and 1500mm 7.Damped capacitive divider RC 1.5MV 8.Capacitive divider 350kV 9.Digital measuring system for LI, SI type TR-AS 100-10/3	-Electric equipment	STAS 6669/1;2;3-86 IEC 60-1/89 IEC 60-2/94 IEC 60694/96 SR EN 60694+A1+A2/96

Contact

Eng. Laurentiu Vladoi
Phone: 0351 404888; 0351 404889
FAX: 0351 404890
e-mail: vladoilaurentiu@icmet.ro

References

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Publications

A.Marinescu, I.Dumbrava, "Numerical method for plotting frequency characteristics of power transformers", First National Symposium on "High Current and High Voltage Tests. Measurements and Qualification of Electrical Equipment", Craiova 26-29 September 1995.

A.Marinescu, I.Dumbrava, "On-line pressure, temperature and humidity measurement in HV Laboratory", Symposium Proceedings "Present State and Tendencies in EMC and HV Engineering", Bucharest November 1997.

A.Marinescu, A. Ungureanu, I.Dumbrava, "Step response evaluation for voltage divider using numerical methods", International Conference of Applied and Theoretical Electronic ICATE'98 Craiova University.

A.Marinescu, A. Ungureanu, I.Dumbrava, "Approximating Polynomials for d(U) Characteristics of IEC 52,
CIGRE 33-99 (WG 03), 25 IWD, Weggis, Switzerland

A.Marinescu, G. Georgescu, V.Filisanu, "Checking and Calibration Proposal for Ultrasonic Transducers used by PD Measurement at Power Transformers, CIGRE 33-99 (WG 03), 26 IWD, Weggis, Switzerland

I. Dumbrava, "The selection of a digital system for recording high voltage impulses according to CEI 61083-1", The 6th National Symposium of High Voltages Technique TTI'99, Bucharest 28-29 October 1999.

A. Marinescu, I. Dumbrava, "Using of frequency characteristics of input admittance of a power transformer to diagnose its mechanical and electromagnetical state", The 6th National Symposium of High Voltages Technique TTI'99, Bucharest 28-29 October 1999.

A. Marinescu, G. Georgescu, T. Nicoara, "Calibration of Acoustic Emission Transducers used to detect PD in Paper-Oil Insulation", Proc of 2-nd Int. Symposium on Advanced Topics in Electrical engineering ATEE-2000, Bucharest 2000

A. Marinescu, Th. Vascan, D. Popa, A. Ungureanu, Fl. Urzica, I. Badea, - Tests of HV DC Underground and Submarine Cables, Symposium "50 years of electric power education in UPB", vol.1, paper 1.43, p.247-252, 10-11 Nov. 2000, Bucharest

A. Marinescu, D. Popa, Th. Vascan, A. Ungureanu, Fl. Urzica, "Some Problems linked to Dielectric Stresses Measurement at HV DC Cables Tests", CIGRÉ WG 33/03, 13 IWD, 2000, Dresden, Germany

A. Marinescu, E. Marinescu, G. Georgescu, V. Filisanu "Gas in Oil Global Detection by Ultrasonic Method",
CIGRÉ WG 33/03, 14 IWD, 2000, Dresden, Germany

A. Marinescu," Measurement of Acoustic Emission Generated by PD in Paper-oil Insulation of power and instrument transformers", Workshop in the framework of Cooperation Research Project ROM 99/006, April 2002, Karlsruhe, Germany

A.Marinescu, A. Ungureanu, I.Dumbrava, D. Popa, Th. Vascan, " Mobile Calibration System for High Voltages
METSIM'2002, 27-28 June 2002, Bucharest

A.Marinescu, E. Marinescu," A Direct Method for On Line Monitoring of Clamping Axial Forces in HV Power Transformers", CIGRE WG 33-03 40 IWD, 2002, Ludvika, Sweden

A.Marinescu, " Monitoring System for Large Power Transformers", CIGRE WG 33-03 41 IWD, 2002, Ludvika, Sweden